Make-it Better
super member
Reged: 06/30/07
Posts: 144
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I have been imaging with a stock 400D for a while and had always considered getting it modded and buying a new camera for daytime use. But with the price of 6MP cooled ccd cameras less than $1500 these days I'm better off just buying one of these and leaving the 400D intact. Are we seeing the beginning of the end of modded DSLR's??
cheers,
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Roy P.
CGE C11
Meade 152ED APO
ED 80
400D
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WarrenS
scholastic sledgehammer
Reged: 03/04/08
Posts: 892
Loc: Orange County New York
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Don't think so.
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Warren
Astro-Tech 127EDT
Celestron Onyx 80ED
Astro-Tech Field Flattener
C8 (circa 1983 Orange Tube)
Atlas EQ-G, Orion SSAG
Canon 135mm F2.8
Canon 40D, Astronomik CLS clip filter
Leica, Minolta binos
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alchemist
super member
Reged: 08/19/07
Posts: 117
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Nop
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ccs_hello
Post Laureate
Reged: 07/03/04
Posts: 3298
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DIY mod is inexpensive.
Clear Skies!
ccs_hello
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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When 6MP - 8MP cooled CCD cameras get down to the $300 - $500 range it will really stop making sens to mod a DSLR. A used Canon 350 can be had for around $300 and modding it can be reasonably cheap too.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
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www.aznightsky.com
Scottsdale, AZ
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David Rosenthal
Carpal Tunnel
Reged: 06/23/06
Posts: 1645
Loc: NJ
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Quote:
DIY mod is inexpensive.
Clear Skies!
ccs_hello
So true!!!! I modded my 400D for, let me see.... $0.00 !!
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David Rosenthal | Midland Park, NJ
My Image Gallery
http://www.EastCoastAstro.com
Atlas EQ-G EQMOD USBDIR [Self-Hypertuned]
8" Meade SCT | Borg 76ED | Takahashi FS-60C
Self Modded 400D | SX MX716 | DSI Pro | SPC900NC
Series 5000 26mm, Hyperion 17mm, TV 11mm Plossl
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Yedgy
sage
Reged: 07/22/08
Posts: 457
Loc: Phoenix, AZ, USA
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Given that modded DSLRs can be had so cheaply, are the days of CCDs almost over? 
Tony
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The Universe is an awesome place. I'm glad I live here.- Takahashi FS-60CB
- HyperTuned Atlas EQ-G
- Mountain Instruments MI-8P pier
- Spectrum-Enhanced Canon EOS 450D
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Rankinstudio
sage
Reged: 04/05/08
Posts: 412
Loc: Salt Lake City, UT, Lake Powel...
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Yea, 6mp CCD is great and all for 1200$, but I got my rebel XSi for under 700$ (w/o lens) and did the mod myself free. Thats 12.2 megapixel of image! Little more time invested in the imaging process, and yous till get stunning results.
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David Rankin
http://www.rankinstudio.com
Astro Gallery
Orion 254mm F4.7 (imaging scope)
Baader MPCC
Quickcam pro 9000 (guider, imager)
Canon Rebel XSi (self modified)
Atlas EQ-G (EQ MOD)
Canon 50mm F1.8 II Lens
Canon 28-200 F3.2 Lens
DSLR peltier cooler
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Nils_Lars
Post Laureate
Reged: 01/04/08
Posts: 3422
Loc: Santa Cruz Mountains , CA
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Well besides the fact that im not going to spend $1500 on a camera that I cant use in the daytime , I get alot of other uses out of my DSLR and that made the purchase a lot easier to sell to the CFO.
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Erik
Orion Atlas Self Hypertuned (EQMOD)
Orion ED 80
Williams Optics VII reducer
Celestron 8" SCT
Orion Starshoot Autoguider
PHD guide
Canon 400D Hap Griffin Mod w/Baader filter
Astronomik clip-in LP filter and 12nm Ha
Stilleto CVF and Bahtinov mask
Tamron 75-300mm&28-80mm lenses
NexImage webcam
http://www.flickr.com/photos/31986095@N05/
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Craig Stark did a head-to-head test between a modified 350D and a Q8-HR in the December 2007 issue of Atro Insight, and the CCD came out significantly ahead. The signal / noise on a cooled CCD is just much better than what you can achieve with a DSLR.
Maybe you if you built one of those custom coolers around the DSLR you might get similar results. The advantage for the QHY8 / Q8-HR / Orion Starshoot Pro cameras is primarily the cooling, not the sensor.
But some of us aren't handy enough to build stuff like that, or do our own mods. So until you see someone offering reasonably-priced coolers for sale for the inept, the low-priced CCDs will be attractive.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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Good point Gus.
DSLR requires a fair amount more work to get the same kinds of results as cooled CCD, but I've gotten great images using my modified DSLR. Temperature is the biggest enemy and living in Phoenix makes about 6 months of the year off limits for imaging.
That is why I have invested so much time and energy working on my cooling box. Using dry ice greatly simplifies the construction and according to my preliminary tests works great. One could build a cooling box like mine for less than $50 in materials and an afternoon of time. Combined with a modest modified DSLR and you have an imaging solution 1/3rd the cost of a dedicated CCD that is usable for daylight shots and on a par with the CCD for image quality.
Click here to see what I did.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
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www.aznightsky.com
Scottsdale, AZ
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astrokido
space wanderer
Reged: 06/09/08
Posts: 662
Loc: Phoenix, AZ
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From what I've been seeing in the last few years it looks to me like DSLRs are actually getting much better for AP than ever. I always check new camera sample images for noise in shadows among other things and in general, every year they have less noise. If manufacturers can keep reducing thermal sinsitivity in sensor chips like they have been it'll only get better for APers. I can't wait for the day DSLRs sample only light, instead of electrons wizing across the photodiode junctions due to their thermal energy.
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- Gill C. - Celestron Cometron CO-100, 10x25, 20x80, Binochair, Nikon D40
The Night Sky Atlas: www.nightskyatlas.com
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Yedgy
sage
Reged: 07/22/08
Posts: 457
Loc: Phoenix, AZ, USA
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Please pardon the temporary thread hijack:
Quote:
Temperature is the biggest enemy and living in Phoenix makes about 6 months of the year off limits for imaging.
Chris, I don't know if you're an EVAC member, but have you gone imaging at Griffin Ranch or anywhere up north in the summer? I'd like to know if the temps make it worth the effort to escape to the high country next summer to keep my darks from being lighter than my lights.
Tony
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The Universe is an awesome place. I'm glad I live here.- Takahashi FS-60CB
- HyperTuned Atlas EQ-G
- Mountain Instruments MI-8P pier
- Spectrum-Enhanced Canon EOS 450D
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Kolenka
Pooh-Bah
Reged: 06/01/08
Posts: 1009
Loc: Seattle Area, WA, USA
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Quote:
From what I've been seeing in the last few years it looks to me like DSLRs are actually getting much better for AP than ever. I always check new camera sample images for noise in shadows among other things and in general, every year they have less noise. If manufacturers can keep reducing thermal sinsitivity in sensor chips like they have been it'll only get better for APers. I can't wait for the day DSLRs sample only light, instead of electrons wizing across the photodiode junctions due to their thermal energy.
If only that happens in our lifetime. Current electronics technology revolves around the core concept of electron flow. Until we change that, every sensor will be doing some trick to sample light by converting it into electron flow. That conversion alone means we will always have some amount of noise.
It doesn't help that all current integrated circuit design uses semiconductors in consumer products. While they are the easiest way to produce chips, they have rather surprising thermal properties that are one of the main sources of thermal noise in a CCD or CMOS chip. As temperatures rise, their ability to pass current increases (producing more heat), which could easily have effects on what you read from the pixel.
Still, we have some headroom left in improving the signal to noise ratio.
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Orion XX12 / Orion 80ED OTA / AT66ED
Nagler 7T6, 9T6, 13T6, 17T4, 26T5
Canon XS, TIS DMK 31AF03, AstroTrac TT320X
Northwest Astro Photoblog
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Modded DSLR will stay a budget solution for a long time to come. Cooled CMOS imagers will never be that cheap: lower production numbers will keep them more expensive than the mass produced entry level DSLRs. My self modified 20D cost me less that 600 Euro and you can have a modded 350D for less than 300 Euro if you do the mod yourself. Add in that you need a somewhat more decent laptop to use such a camera that adds in the cost as well. The relic laptop that does my autoguiding cost me 50 Euro... But I'm sure it won't like 6MP images coming through it's USB 1.1 port 
That said, I am also considering one of those cooled CMOS imagers as my next camera... Maybe I'll mod a 40D to fill the gap, though. $1500 on a dedicated astro camera is a bit too much for my budget at the moment.
Koen
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Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
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nytecam
Postmaster
Reged: 08/20/05
Posts: 5750
Loc: London UK
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Quote:
Given that modded DSLRs can be had so cheaply, are the days of CCDs almost over? Tony
Nop - don't see the pro-astronomers going down to the cameramart  all down to QE and DSLR are designed like most human activity for use in DAYLIGHT where there are too many photons 
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Nytecam 51N 0.1W
Meade 30cm LX200+ETX-70+e-finder+C8+Ha+CaK PSTs SBIG SGS+homebuilt spectrographs
Starlight SXVF_M9+Lodestar CCDs/Canon 300D DSLR/Fuji E550
My observatory build-ETX-70 imaging-my videos
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Quote:
My self modified 20D cost me less that 600 Euro and you can have a modded 350D for less than 300 Euro if you do the mod yourself.
I still say it's not appropriate to assume self-modification. Modification is not for the faint of heart, and can destroy your camera if you screw up. Not to mention the fact that you really have to do it under clean-room conditions if you don't want to risk dust trapped under the IR filter, and setting that up isn't trivial either.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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greekoh
sage
Reged: 03/12/06
Posts: 300
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I've had the best result with a Canon 20d mod however I'm curious if the following does make a difference
Most cost effective DSLR's seem to be 12 or 14 bit color as apposed to the 16bit CCD's.
Individual Pixels size on the CCD's appear to be bigger and my understanding is this in turn will show more detail.
Bigger buckets
I realize the higher end DSLR's such as the Canon 5d's and Marks are in a different category.
Anyone having the pleasure of owning both for a honest comparison?
Particularly a Canon 350,20d,40d and maybe a Meade DSI III C or QHY8
Troy
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Quote:
I still say it's not appropriate to assume self-modification. Modification is not for the faint of heart, and can destroy your camera if you screw up. Not to mention the fact that you really have to do it under clean-room conditions if you don't want to risk dust trapped under the IR filter, and setting that up isn't trivial either.
- Gus
Self-modification is not even required. Most of us are associated with some sort of local astronomy club, which often burst with people with great technical skills. I know several persons who could do it for me and 1 that would even be able to get it done in clean room conditions at a price well below of what Hutech or Baader charges. Since I'm an electronics engineer, I prefered to do it myself (under less than clean room condition - my mother ran into my room with a pile of freshly washed and ironed clothes while I had the sensor in my hands).
Sure opening up a camera is a big step, but it isn't that much harder than cleaning optics or tuning a mount... I find myself way less comfortable handling the mirror of my 14" Dobsonian after cleaning than with the sensor of a camera, but yeah, I clean all my optics myself. I'm personally not too fond of mechanics, but I wouldn't hesitate to open my GM-8 if it's needed.
Koen
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Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
Edited by Kentari (12/12/08 09:41 AM)
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DaemonGPF
Post Laureate
Reged: 03/22/08
Posts: 3563
Loc: New Mexico
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Quote:
Individual Pixels size on the CCD's appear to be bigger and my understanding is this in turn will show more detail.
Bigger buckets
I thought the bigger the pixel, the higher the sensitivity, but lower sampling, and the resolution is more dependent on the actual chip size?
An example:
ATIK314E vs ATIK314L
6.45um pixels in one, and 4.65um pixels in the other. One is a 1/2 chip and the other is a 2/3. Both produce 1392x1040 resolution. However, the one with smaller pixels produces much better sampling but suffers lower sensitivity(assuming I did my math right... lol) The FOV is better on the larger chip as well.
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-Josh
http://cleardarksky.com/c/AlbuqNMkey.html
My AP Gallery
Edited by DaemonGPF (12/12/08 10:02 AM)
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Quote:
Most of us are associated with some sort of local astronomy club, which often burst with people with great technical skills.
Is that really true? Sometimes I get the impression that a fair amount of the community is relatively solitary, like myself. I don't belong to an astronomy club, and the closest one I'm aware of is a fair drive away.
Quote:
Sure opening up a camera is a big step, but it isn't that much harder than cleaning optics or tuning a mount...
... neither of which I really feel up to either. Well, maybe I could dismount the mirror and clean it though I haven't tried that yet. Tuning my mount is well beyond my skills.
My limit with the camera is cleaning the dust off myself with a swab when a static-charged brush doesn't work. I'm not afraid of a soldering iron, but changing the filter involves a lot more than that.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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MartyT
professor emeritus
Reged: 09/28/07
Posts: 682
Loc: Kansas City
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I haven't taken a picture with my modified 350D since the day my QHY8 arrived.
I also haven't wasted time taking a single dark frame since then either...
And I haven't had to fight any kind of amp glow...
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Celestron CGE / C-11 (CGE-1100)
Megrez 90 FD APO / 0.8x FR/FF vIII
QHY8, 350D, DSI Pro, SPC900NC
KWIQ Guider (QHY5)
ETX-125AT
12" Lightbridge
My Astrophoto Gallery
Astronomical Society of Kansas City
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Kolenka
Pooh-Bah
Reged: 06/01/08
Posts: 1009
Loc: Seattle Area, WA, USA
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Quote:
Quote:
Individual Pixels size on the CCD's appear to be bigger and my understanding is this in turn will show more detail.
Bigger buckets
I thought the bigger the pixel, the higher the sensitivity, but lower sampling, and the resolution is more dependent on the actual chip size?
An example:
ATIK314E vs ATIK314L
6.45um pixels in one, and 4.65um pixels in the other. One is a 1/2 chip and the other is a 2/3. Both produce 1392x1040 resolution. However, the one with smaller pixels produces much better sampling but suffers lower sensitivity(assuming I did my math right... lol) The FOV is better on the larger chip as well.
Yup, there is just one additional gotcha here. How much of a gap exists between pixel sites that would cause light to be lost to the sensor. One of the reasons that the new 50D has much better noise levels is because Canon figured out how to use more of each pixel site to collect light, upping the efficiency that way. The design of CCDs tends to give it this sort of advantage naturally.
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Orion XX12 / Orion 80ED OTA / AT66ED
Nagler 7T6, 9T6, 13T6, 17T4, 26T5
Canon XS, TIS DMK 31AF03, AstroTrac TT320X
Northwest Astro Photoblog
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Andrew Welsh
Carpal Tunnel
Reged: 03/28/06
Posts: 2483
Loc: Rochester, NY
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Quote:
Click here to see what I did.
A little OT, Chris.. how do you deal with the changing weight of the box? Wouldn't that potentially throw the balance of the scope off? What about the changing temperature and matching darks? And where does one buy dry ice and at what cost
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LX200 8" classic, f/10, Meade eq. wedge, .63x FF/FR
Canon 40D and 5D, unmodified
Canon EF 300/2.8L IS, 400/5.6L, 135/2L, 50/1.8, 85/1.8, 35/2, 24-70/2.8L, and Peleng 8mm fisheye
Orion Apex 102mm (4") Mak-Cass
Pimped out with accessories and bling
My DSLR Astrophotography Webpage and photo bucket with full equipment list
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jgraham
Postmaster
Reged: 12/02/04
Posts: 6758
Loc: Dayton, Ohio
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In part this may come down to better versus good enough. Comparing one shot color systems DSLRs have a lot to offer, particuarly on the basis of cost. As the cost gap narrows and you start diving into performance issues I don't think CCDs distinguish themselves until you get into condtions where thermal noise becomes and issue (long exposures under dark skies). For some (that's me) that doesn't come into play since we don't image under conditions that permit us to run into these issues. From my back yard 3 minute subs are the absolute max I can go before light pollution (even with an IDAS LPS-2) consumes 30-50% of my dynamic range. A large format CCD may be techincally better, but my DSLR is certianly plenty good enough, particularly with the new 14 bit DSLRs coming online (the XSi). Also, having been around a while, I wouldn't consider another small color CCD for any reason, cooled or not. Large format CCDs like the new Orion Starshoot are heading in the right direction, but even the Starshoot is a factor of about 2 times as much as a DSLR.
Now monochrome CCDs are another matter, there's so much you can do with even a small monochrome imager that I place them in another branch of the imaging family tree.
Coming from an old film background (from way back when we used to build our own cameras and develop our own film) it's been a lot of fun watching the technology progress. One thing that's clearly helping the DSLR market is the market volume versus the more niche astronomical imager market. I was so excited to fianlly find an affordable DSLR (my XTi) that was a worthy replacement for my old friend, my Olympus OM-1.
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-John
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Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I, II, & III), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Quote:
Yup, there is just one additional gotcha here. How much of a gap exists between pixel sites that would cause light to be lost to the sensor. One of the reasons that the new 50D has much better noise levels is because Canon figured out how to use more of each pixel site to collect light, upping the efficiency that way. The design of CCDs tends to give it this sort of advantage naturally.
Except those with anti blooming features (and you don't want blooming...), which also reduce the light capturing area...
Dedicated CCD/CMOS cameras of course have major benefits:
- temperature control: perfectly matched darks and imaging at low temperatures!
- 16-bit sampling
- monochrome sensors = much more light captured instead of throwing 2/3rd away
But they come with drawbacks too:
- they are dedicated - no taking pics of the wife and kids with these babies
- and expensive (we are calling a $1500 machine cheap here...)
- a laptop or computer is mandatory, where a DSLR can go without
- expensive RGB filters if you go monochrome (which in my opinion is the only right way with a dedicated camera)
Resolution and field of view are dependent on the sensor you pick. This should be matched to the telescope or lens you intend to use and the kind of objects you intend to photography. Here too you have somewhat more flexibility than with DSLRs. Personally I favor field of view over resolution and work well undersampled (I also live in a country with lousy seeing...).
Koen
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Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Quote:
Is that really true? Sometimes I get the impression that a fair amount of the community is relatively solitary, like myself. I don't belong to an astronomy club, and the closest one I'm aware of is a fair drive away.
Well, that't the picture I have from amateur astronomy here. There are 6 big local observatories, dozens of small groups of observers and one big national association for amateurs here in Flanders, which is only 13000 square kilometers (about the size of Connecticut). There are loners, but I believe they are a minority here...
Quote:
... neither of which I really feel up to either. Well, maybe I could dismount the mirror and clean it though I haven't tried that yet. Tuning my mount is well beyond my skills.
My limit with the camera is cleaning the dust off myself with a swab when a static-charged brush doesn't work. I'm not afraid of a soldering iron, but changing the filter involves a lot more than that.
I didn't look forward to do any of these things either (except modding the camera - I was just so thrilled about the improvement I would get), but all in all, stuff is delicate, but not that delicate. If you are careful and patient it all turns out well. Just look up some manuals on the net, read them, read them again and proceed carefully, with a manual at hand...
Koen
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Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
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Agnotio
sage
Reged: 08/29/08
Posts: 230
Loc: Ottawa, Canada
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Quote:
Quote:
Most of us are associated with some sort of local astronomy club, which often burst with people with great technical skills.
Is that really true? Sometimes I get the impression that a fair amount of the community is relatively solitary, like myself. I don't belong to an astronomy club, and the closest one I'm aware of is a fair drive away.
- Gus
I agree with you on that impression Gus. Most of guys in my local astronomy club seem to be pretty asocial, and those are the ones who showed up. Sure some of them are technical wizards, but making a friendship with a person such that you would trust them to modify your 500$ DSLR is a different story.
I also agree with you that most amateur astronomers won't/can't modify their own DSLR's, however appealing the cost-saving can be. And that's probably a major factor in whether they go over to CCD's or not.
For myself, I would rather bite the bullet and pay Hutech to do the modification than risk ruining my camera. But to each his own.
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Sky-Watcher Equinox 80ED
EQ6 Pro with EQMOD
Canon 450D
Sky-Watcher 10" f/4.7 Dob
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Aquatone
member
Reged: 03/23/06
Posts: 85
Loc: Moraga, CA (Bay Area)
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The portability and "instant gratification" aspect of a modified DSLR (a self contained imaging machine) is a huge advantage IMO. Often it is small things - for example with Live View even focusing is much easier than the more drawn out processes you often have to use with a dedicated astronomical camera. The fun of taking quick and easy shots is surely just as important in what for most is a hobby.
Sure if I am after really deep shots I would use an STL11K but taking a laptop, tons of cables, and sustainable power supplies into the field (or even my back yard) hardly makes it grab and go imaging - and certainly not the instant gratification experience you can realize with a DSLR. And that is what it is... its a different "experience".
There is a place for both.
Chris
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Astro-Physics 160 EDF
Astro-Physics 10" Maksutov Cassegrain
Borg 77 ED
AP Mach 1.0 GTO
AP1200 GTO
Custom software development pipeline
Edited by Aquatone (12/12/08 11:54 AM)
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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Quote:
Quote:
Click here to see what I did.
A little OT, Chris.. how do you deal with the changing weight of the box? Wouldn't that potentially throw the balance of the scope off? What about the changing temperature and matching darks? And where does one buy dry ice and at what cost
Changing weight is trivial. I can pack about 600 grams (about 1.5 lbs) of ice in the box. If a change of 600 grams is significant with your mount and scope then this box isn't for you. With my AP160 on my AP900 this change in weight is insignificant to the balance of the scope, but your mileage may vary.
The changing temperature is a potential issue. However the temperature seems to follow a nice curve down (reaching equilibrium and thus not changing much afterward in about 2 hours). One could theoretically pre-cool the camera before dark. Once at equilibrium it will slowly warm as the ice sublimates. This is a very slow process changing about 5 degrees per hour in the beginning. In my experience this isn't enough to throw the darks off. Also I keep track of the temperature as I go so I can reproduce the temperature of the camera at a future date if necessary and capture darks then. Keep in mind that with ambiant temperatures of 71F my camera is down to 17F. Darks become much more trivial down that low. 10 degrees here or there won't make much difference to the final product. One issue is if the ice shifts as the scope tracks. This is something I need to test for on the scope itself. This could be an issue imaging past the meridian. However you may loose one sub when it shifts so is likely not a show stopper.
You can get dry ice at most grocery stores. You have to ask for it because they don't want customers reaching in there and grabbing a slab and getting frost bite. I've found it for $.99 a pound at Fry's and $1.50 a pound at Bashes here in Scottsdale AZ.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
----------------------------
www.aznightsky.com
Scottsdale, AZ
Edited by cvedeler (12/12/08 12:22 PM)
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imjeffp
Aluminum Falcon
Reged: 09/30/03
Posts: 4902
Loc: Cedar Park, Texas
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One thought I have is that any improvements in sensor technology incorporated into DSLRs will/could also be incorporated into cooled dedicated astro cameras.
If Canon thought they could sell enough (which sadly I don't think they could), it seems to me they could build an astro cam for less than the cost of a DSLR. Consider: no shutter or moving mirror, no AF, no programming for multiple exposure modes, no flash, a greatly simplified housing, no prism, no display. Just a sensor, an interface, a power supply and a cooling system.
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soreneck
scholastic sledgehammer
Reged: 04/01/06
Posts: 920
Loc: Toronto, Canada
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This is a very interesting discussion. I've debated where to go next in my imaging upgrade path. Was using a modified 350D for 2 years, considered the QHY8 seriously, but recently decided to go for the live-view-equipped 450D instead for many of the reasons listed (cost, dual-use for daytime, laptop-free portability if required).
However, this will be my last DSLR for astro use. Once I've saved enough cash, I will go to a STL11000 for observatory use, and even then I'll continue to take my DSLR on dark-sky excursions where portability demands that I work without a laptop.
Still, I agree with Chris:
Quote:
Sure if I am after really deep shots I would use an STL11K but taking a laptop, tons of cables, and sustainable power supplies into the field (or even my back yard) hardly makes it grab and go imaging - and certainly not the instant gratification experience you can realize with a DSLR. And that is what it is... its a different "experience".
There is a place for both.
We're fortunate in this hobby to have so many options!
Cheers,
Adam
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Adam
WO 110 FLT / WO 66 Triplet
QHY9 / Modified Canon 450D
SkyWatcher EQ-6 Pro
Backyard (urban) roll-off observatory
One small but fearless dog (observing companion)
my astrophotos on flickr
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jgraham
Postmaster
Reged: 12/02/04
Posts: 6758
Loc: Dayton, Ohio
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If it were me (and it's not) and I were using a DSLR for imaging and pondering a CCD I'd take a hard look at going with a monochrome camera. I find that there's so much overlap between a color CCD and a DSLR that it's mostly more of the same whereas a monochrome CCD is a very different experience and in many ways far more capable than a color camera (dedicated CCD or DSLR). You can also do a lot with a small entry-level monochrome CCD (like the Meade DSI Pro series or Orion Starshoot series) while the comparable color CCDs can be disappointing compared to the monster array used in a DSLR; a small section of a DSLR image looks a lot like a full frame from a type 1/3 or 1/2 color CCD while the same area taken with a monochrome CCD is about 3x as sensitive and much sharper.
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-John
================================================
Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I, II, & III), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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Aquatone
member
Reged: 03/23/06
Posts: 85
Loc: Moraga, CA (Bay Area)
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I agree with this. The color CCD cameras (especially the cheaper ones) offer many of the disadvantages of a dedicated astronomical CCD camera (cables, laptops, much less portable, less instant gratification) with few of the gains of a cooled sensitive monochrome CCD. To me that is why DSLR's and dedicated (monochrome) CCD cameras are at opposite ends of the imaging spectrum. I suspect there is still a long life for modified DSLR's yet.
Chris
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Astro-Physics 160 EDF
Astro-Physics 10" Maksutov Cassegrain
Borg 77 ED
AP Mach 1.0 GTO
AP1200 GTO
Custom software development pipeline
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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With the current state of the / my economy I don't see upgrading to CCD anytime soon. I've got to make due with what I have. When things improve I'll be looking to get a CCD eventually. I want a full frame camera. With my setup half of the photons captured and precisely focused land outside of the imaging chip of my Canon DSLR.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
----------------------------
www.aznightsky.com
Scottsdale, AZ
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Aquatone
member
Reged: 03/23/06
Posts: 85
Loc: Moraga, CA (Bay Area)
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(Small aside) Chris - Astro-Physics have just mailed me the new AP160 Field Flattener/TCC to Canon adapter. (Part ADATCCEOS) When I get my a 5D Mark 2 I am looking forwards to seeing how this optical marriage works!
Chris
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Astro-Physics 160 EDF
Astro-Physics 10" Maksutov Cassegrain
Borg 77 ED
AP Mach 1.0 GTO
AP1200 GTO
Custom software development pipeline
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quantumac
sage
Reged: 12/17/07
Posts: 387
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I just went from Canon 450D Xsi to QHY8. Originally, I had planned to modify the 450D once the warranty expired. Then I discovered the QHY8 could be operated from Mac OS X using Nebulosity, and the noise issue was so much less. Since I use a laptop to image with anyway, and I have a dedicated observatory, having a dedicated camera didn't seem much of a stretch.
While the latest crop of dedicated astronomical cameras aren't "cheap" at ~$1.5K, they also aren't ~$8K to ~12K like certain premium offerings. I'd love to own one of those high-end cameras, but I can't see spending what it took to build my entire observatory and fill it with telescope equipment just to purchase a single, dedicated sensor. To me, the premium price point just doesn't make sense.
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Scope: Meade 10" LX200R
Guide/Planetary Camera: Imaging Source DBK41AF02.AS
DSO Camera: QHY8
Guide Hardware: Celestron OAG, Shoestring Astronomy GPUSB
Software: Mac OS X, Starry Night Pro, Nebulosity, PHD Guiding, PixInsight, Astro IIDC. No Windows anything.
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lawrie
Carpal Tunnel
Reged: 01/31/06
Posts: 1742
Loc: Okanagan Valley
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With the prices coming down and chip size going up, dedicated CCD's (like the QHY8) will increase. People will still use DSLR's but with cooling and the higher sensitivity of these CCDs I think modding will be done less and less.
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Clear Skies
Lawrie
Ultima 8
Atlas EQ-G
ZenithStar 80 FD
DSI Pro - Pro II
Canon 350D
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greekoh
sage
Reged: 03/12/06
Posts: 300
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Quantumac
What differences if any have you noticed?
I'm real curious if you can capture certain colors not possible with a DSLR?
Also wondering if the detail is any better ?
Dont be afraid spill the beans 
Troy
Troy
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ccs_hello
Post Laureate
Reged: 07/03/04
Posts: 3298
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My .02
Under (severe) budget constraint, I would suggest getting all of the following 3 imaging devices:
1) Philips ToUCAM/SPC900NC
2) DSI Pro (or Pro-II) or Orion's
3) Canon XS (a.k.a. 1000D),
if you can spare $160 more which is 35%~40% more, then get a Rebel XSi (450D)
For #3, if your friend is willing to do a mod for you w/o warrenty, go for it. It's a 12-bit, has Live-Preview, and uses CMOS sensor. Please check the price around, you'll be surprised. The cost is very low. If it has failed due to mod, the pain will last shorter. Sorry no active TEC cooling  .
BTW, two pieces of info (.01 each):
1. The APS-C sized OSC astro-CCD imagers priced around $1300-$1500 all use the sensor also used in the (6Mpxl CCD) DSLRs (and may even came from a donor DSLR -- cheaper that way).
{flame off}
2. The sensor mentioned above itself is bounded by the sensor S/N it can offer, which BTW is translated to approx. (ideally) 13 bit or so.
{flame on}
Clear Skies!
ccs_hello
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DaemonGPF
Post Laureate
Reged: 03/22/08
Posts: 3563
Loc: New Mexico
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Quote:
Quote:
Most of us are associated with some sort of local astronomy club, which often burst with people with great technical skills.
Is that really true? Sometimes I get the impression that a fair amount of the community is relatively solitary, like myself. I don't belong to an astronomy club, and the closest one I'm aware of is a fair drive away.
I'm an AP hermit as well.. but I'm not sure if it's by choice only because I don't know anyone relatively near me that is in to AP or even has a telescope for that matter. I don't really have a club or association to be tempted by unless I drive a good way out, which I have zero inclination to do since I already live in a dark area.
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-Josh
http://cleardarksky.com/c/AlbuqNMkey.html
My AP Gallery
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Why a SPC900NC and a second guide camera? For planetary photography?
I have both myself, and I use the SPC900NC for drift-alignment, which isn't possible at present with the Starshoot Autoguider. Only because of lack of drivers for anything but PHD. But I don't think most people do that.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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Strgazr27
Vendor - Deep Space Mods and Composites
Reged: 10/04/04
Posts: 6984
Loc: StonyHill Observatory
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Quote:
Why a SPC900NC and a second guide camera? For planetary photography?
I have both myself, and I use the SPC900NC for drift-alignment, which isn't possible at present with the Starshoot Autoguider. Only because of lack of drivers for anything but PHD. But I don't think most people do that.
- Gus
SSAG drivers are available for both MaximDl as well as CCDSoft. In a picnh you may also be able to use QHY5 drivers but I never had to. Drift alignment can also be done via PHD by turning guiding corrections off and graphing on. You'll be able to see the drift, correct for it and repeat. You can also use PEMPRO via any of the ABOVE mentioned softwares except PHD.
Just wanted to clear that up.
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Bobby
StonyHill Observatory
Skywatcher EQ6 Pro (On it's way)
AT 130 F/6 Prototype
Royce 10" f/4 Astrograph (Under Construction)
Self Modded 40D
70-200 F2.8 L IS
SSAG
YAHOO TMB 130SS Group
Astronomy Technologies Yahoo Group
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ccs_hello
Post Laureate
Reged: 07/03/04
Posts: 3298
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Quote:
Why a SPC900NC and a second guide camera? For planetary photography?
Gus,
Yes.
Clear Skies!
ccs_hello
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Asturies
sage
Reged: 06/14/07
Posts: 207
Loc: La Mancha, Spain
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There's one thing nobody is stating. The (In my opinion) greatest difference is that if you want to improve from just doing nice images of the night sky to do a little science like photometry (is this right spelled?)you need a B&W dedicated CCD.
For me when I grow up (a little more)
Regards, Fernando
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LX90 12" with ultrawedge
CG5-GT
Equinox 80mm APO
Mak-Cass 100mm f/14
PST Repaired of rusty objective
Canon EOS 350D
Brand new DBK21 for guiding and planetary
My web translated to English at last!!!
http://perso.wanadoo.es/jfa926/Fernando_Mejido/index.htm
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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That is a good point Fernando. For science work a CCD is the only real option. But for pretty pictures a DSLR can do amazing things.
--------------------
Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
----------------------------
www.aznightsky.com
Scottsdale, AZ
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Quote:
SSAG drivers are available for both MaximDl as well as CCDSoft.
Those do automated drift alignment? I didn't know that.
Quote:
Drift alignment can also be done via PHD by turning guiding corrections off and graphing on.
True, but that doesn't give you the actual correction, just the direction. It's seat of the pants at that point, as opposed to a program has you move a target star with the alt / az adjustments to the correct spot.
Of course, to be fair, WCS is often off by so much in its calculations that it's almost seat of the pants as well.
Quote:
You can also use PEMPRO via any of the ABOVE mentioned softwares except PHD.
I think I've read that PEMPRO does what WCS does, I just haven't tried it out because of the price tag.
- Gus
--------------------
Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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UniversalMaster
super member
Reged: 11/20/08
Posts: 177
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I just ordered a used modded DSLR from astronomiser for about 1/4 the price of a Orion SS 6MP, and that was stretching it a bit economically. So there is no way I will be able to afford a CCD and time soon, but a modded DSLR was just within my reach. Also, if Im going to CCD sometime, it will be black and white.
There is also this for polar alignment (free!):
http://eqalign.sourceforge.net/index-en.html
Søren
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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I tried Eqalign, and couldn't get it to work. It had no trouble talking to the SPC900NC, but when it came time to get a correction, I got bizarre results.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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Alex Post
sage
Reged: 09/24/08
Posts: 454
Loc: Iowa, USA
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Quote:
Click here to see what I did.
This is impressive. Where do you get dry ice?
--------------------
Bino: Celestron SkyMaster 15x70, WO Binoviewer
Scope: Celestron NexStar 8SE, Stellarvue 9x50 Finder
EP: Hyperion 8mm 13mm 2x21mm(bino), 14/28mm FTRs, StellarVue 23mm with Rigel Pulse Guide
Misc: William Optics 2" Dielectric, DewBuster, Celestron f/6.3 FLR, Canon 300D and XSi, JMI Motofocus, Hutech IDAS LPS 2"
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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Many grocery stores carry dry ice. Call around. It is about $1 per pound.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
----------------------------
www.aznightsky.com
Scottsdale, AZ
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alchemist
super member
Reged: 08/19/07
Posts: 117
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I prefer a Dslr mod. because is easy to use and no need a laptop and the most important thing "for me" is: I can use my Hoya R72 filter with it and enjoy beautiful infrared landscape photography 
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Samir Kharusi
scholastic sledgehammer
Reged: 06/14/05
Posts: 985
Loc: Oman
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Interesting thread. Having started off with film and an astroCCD and migrated to modded DSLRs, perhaps it's time I peeped back into astroCCDs, seeing that prices have come down drastically. I am only interested in a camera that can deliver pro-quality A3-sized prints. My lenses and mounts can, so I want the limiter to be just me, not the camera. Any current DSLR can do that, also $10,000 astroCCDs. But can anyone suggest a mono astroCCD that can do that for under $5000 (including the base 3 RGB filters)? For A3 prints I figure I need at least 6 megapixels.
--------------------
Bored? Peruse my website:
http://www.samirkharusi.net/
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Make-it Better
super member
Reged: 06/30/07
Posts: 144
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The mono 8mp QHY9 is about $2600 and $500 more for the filter wheel when purchased with the camera. I have been thinking about this myself.
link: QHY9 Supplier
Cheers,
--------------------
Roy P.
CGE C11
Meade 152ED APO
ED 80
400D
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Samir Kharusi
scholastic sledgehammer
Reged: 06/14/05
Posts: 985
Loc: Oman
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That QHY9 certainly looks very enticing, even for my C14 Hyperstar. At last! A serious mono astroCCD at a DSLR-competetive price. Mind you, the Sony chips seem to get better astro press, but it seems for mono one has to use Kodak.
--------------------
Bored? Peruse my website:
http://www.samirkharusi.net/
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UniversalMaster
super member
Reged: 11/20/08
Posts: 177
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Couldn't one capture luminance or narrow-band with the mono CCD and RGB data with a modded DSLR to save time?
Søren
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justabob
Carpal Tunnel
Reged: 05/05/07
Posts: 1681
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Quote:
Couldn't one capture luminance or narrow-band with the mono CCD and RGB data with a modded DSLR to save time?
Søren
Yes indeed. This is pretty easy if you use registar.
--------------------
http://www.pbase.com/rkn/astro&page=all
Vixen Sphinx SXW
Meade sn6
Canon EF 200mm f/2.8L II USM Lens
Hutech 1000d
Self modded 350d
ST8300c on order
DSI PRO II
Bob
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7834
Loc: Lexington, SC
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Quote:
That QHY9 certainly looks very enticing, even for my C14 Hyperstar. At last! A serious mono astroCCD at a DSLR-competetive price. Mind you, the Sony chips seem to get better astro press, but it seems for mono one has to use Kodak.
I'm in the same boat. I've watched and followed your work and you are a true professional. If you make the plunge and come up with glowing reviews I sure won't be far behind.
--------------------
Jerry
Celestron C-11
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krneki
super member
Reged: 12/24/05
Posts: 147
Loc: sLOVEnia (45.5° N)
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I couldn't take it anymore, so I ordered the QHY9 
--------------------
William Optics TMB 80/480, Skywatcher 254mm f/4.72
Astronomy Technologies AT66 66mm f/6 ED
Gemini-42 Observatory+, HEQ-5
Canon 350D, QHY5, QHY filterwheel, QHY9
http://astro.krneki.ws/
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Asturies
sage
Reged: 06/14/07
Posts: 207
Loc: La Mancha, Spain
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In my opinion DSLRs and dedicated CCDs play in different leages. With a DSLR you can't never get the results obtained with CCD's, people imaging with CCDs don't mind about light pollution, if you image from a LP site (99% backyards) you can do narrowbanding easily. It is different with the DSLR, if you do narrowbanding you lose a lot of the resolution, I don't think you can get this resolution with a DSLR Rosette nebula
On the other hand DSLRs are ideal for travelling far or abroad to hunt eclipses or auroras, etc.
All this said I love my 350D and before making the jump (apart from saving and get the finances director approval, I mean my wife) I want to get the most of my DSLR.
And yes the QHY9 seems to be a reasonable option, if you save 5K$ for loosing a little in noise I would call it reasonable, a couple of shots more to get more S/N and costs recouped
Regards, Fernando
--------------------
LX90 12" with ultrawedge
CG5-GT
Equinox 80mm APO
Mak-Cass 100mm f/14
PST Repaired of rusty objective
Canon EOS 350D
Brand new DBK21 for guiding and planetary
My web translated to English at last!!!
http://perso.wanadoo.es/jfa926/Fernando_Mejido/index.htm
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Quote:
Interesting thread. Having started off with film and an astroCCD and migrated to modded DSLRs, perhaps it's time I peeped back into astroCCDs, seeing that prices have come down drastically. I am only interested in a camera that can deliver pro-quality A3-sized prints. My lenses and mounts can, so I want the limiter to be just me, not the camera. Any current DSLR can do that, also $10,000 astroCCDs. But can anyone suggest a mono astroCCD that can do that for under $5000 (including the base 3 RGB filters)? For A3 prints I figure I need at least 6 megapixels.
Not quite there yet, but the ATIK-11000 sits around $5000 (without filters) and sports the same sensor as the STL-11000...
Koen
--------------------
Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
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Strgazr27
Vendor - Deep Space Mods and Composites
Reged: 10/04/04
Posts: 6984
Loc: StonyHill Observatory
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Fernando,
There is more than just a high quality CCD involved in that Rosette image
I think the image below by RBA sets a bar and speaks volumes about the capabilities of a DSLR for high resolution work.
One advantage I have not seen mentioned is the 16bit advantage for CCD work. I like a DSLR for several reasons. Number of pixels VS cost, size and if need be, self containment. I also don't have the weather to devote a full night to an object gathering LRGB frames, hoping they all come out good and than spending the additional time needed to process those images. That being said, I miss the sensitivity of the ST-10XE I owned. I miss the incredibly low noise of the SXV-M25C and the QHY8 I have owned and used. What I want from Santa is a 10 Megapixel, cooled DSLR with at least 50% QE in the Ha wavelength........
--------------------
Bobby
StonyHill Observatory
Skywatcher EQ6 Pro (On it's way)
AT 130 F/6 Prototype
Royce 10" f/4 Astrograph (Under Construction)
Self Modded 40D
70-200 F2.8 L IS
SSAG
YAHOO TMB 130SS Group
Astronomy Technologies Yahoo Group
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greekoh
sage
Reged: 03/12/06
Posts: 300
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Any idea how the QHY-8 compares to a modded Canon 20d or 40d?
If you've owned both what do you think meaning are the differences significant enough?
Troy
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Strgazr27
Vendor - Deep Space Mods and Composites
Reged: 10/04/04
Posts: 6984
Loc: StonyHill Observatory
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I did not see any real increase in sensitivity bewteen the 2. What I did see was an incredibly decrease in noise. This allows for longer exposures and the ability to stretch the images further because of the lower noise.
CS's
--------------------
Bobby
StonyHill Observatory
Skywatcher EQ6 Pro (On it's way)
AT 130 F/6 Prototype
Royce 10" f/4 Astrograph (Under Construction)
Self Modded 40D
70-200 F2.8 L IS
SSAG
YAHOO TMB 130SS Group
Astronomy Technologies Yahoo Group
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Since you own a QHY8 - it's mentioned in your signature - do you still use a DSLR? Of the advantages you mention, it would seem that the only advantage of, say, a modded 40D over your QHY8 is number of pixels. The QHY8 is self-contained, not that large, and a one-shot color camera, not LRGB.
- Gus
--------------------
Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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Strgazr27
Vendor - Deep Space Mods and Composites
Reged: 10/04/04
Posts: 6984
Loc: StonyHill Observatory
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Gus,
I owned a QHY. Never took it out of my sig. I have since gone back to my modded 40D. The QHY8 is not self contained. You cannot image with the Q without a laptop as opposed to the 40D. The smaller pixels of the 40D are a better match to the short Fl scopes I have grown to love imaging with. That being said I am currently on the list for another QHY8. I like the larger pixels at times as well as the lower noise. It will mostlikely be a warm weather camera as the noise level from the 40D under 45-50 degrees is not enough to make me stop using it. We average low 20's here in the winter so noise is not an issue, good seeing is. Now in June,July and August when it's 80 degrees at 11pm and 80% humidity the 40D will stay in the case.
I find color balancing the 40D with the CLS to be easier. I always found it a bit difficult to arrive at a good color balance with the Q without more work than the 40D.
--------------------
Bobby
StonyHill Observatory
Skywatcher EQ6 Pro (On it's way)
AT 130 F/6 Prototype
Royce 10" f/4 Astrograph (Under Construction)
Self Modded 40D
70-200 F2.8 L IS
SSAG
YAHOO TMB 130SS Group
Astronomy Technologies Yahoo Group
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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I've found that I need the laptop for so much in order to get good images, needing a laptop for the QHY8 doesn't seem like a huge drawback. Framing for large objects (Western Veil or M31), precise focus, guiding, I can't really manage any of those without a laptop. I often have to look at stretched exposures to assure myself I've got the target at all, and that needs a laptop as well.
The one that's really hard to get around is guiding. How many autoguiders are left that don't require a laptop? I know some of the more expensive CCDs have autoguiding built in, but they're really expensive.
I need to pay more attention to color balance myself, I'm just going through the routine, rather than doing anything smart like shooting a gray card. Can't you do that with the QHY8? Or are you talking about using the in-camera custom white balance and software that can read that, versus manually balancing a gray card?
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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Nate B.
sage
Reged: 03/08/07
Posts: 282
Loc: Pittsburgh, Pennsylvania
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I started out with a Canon 5D, then a modded 30D, and now a QHY8. Certainly, my modded DSLR time has come and gone. When it will happen for everyone though I think depends on what you image and where you do it. Living in a city, I now image at least 10 times more than I used to because I can do narrowband work much more effectively with the QHY8 than I could with my DSLR. If I lived out in the country I'd have probably stuck with the DSLR for a longer period of time. If I had known this then I would have started this hobby with the larger upfront cost of the astro-ccd. Being able to image more often is priceless and is a distinct benefit of an astro-ccd for me. I feel like all that extra ccd money I spent went towards convenient imaging from home on a more frequent basis. It was money well spent for me.
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Tak FSQ-106EDX
Pentax 75 EDHF 75mm f/6.7 APO
Apogee Alta U8300 CCD
Orion Atlas EQ-G Mount with EQMOD
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MartyT
professor emeritus
Reged: 09/28/07
Posts: 682
Loc: Kansas City
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Quote:
I need to pay more attention to color balance myself, I'm just going through the routine, rather than doing anything smart like shooting a gray card. Can't you do that with the QHY8?
You can shoot a gray card with the QHY8 and use it to determine R:G:B ratios for use in DeepSky Stacker, etc. if you want to. But it's really not difficult to get a good color balance in post-processing. Plus DSS does a pretty good job of aligning the color channels initially if you ask it to - it certainly does better on the QHY8 than it ever did on my modified 350D.
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Celestron CGE / C-11 (CGE-1100)
Megrez 90 FD APO / 0.8x FR/FF vIII
QHY8, 350D, DSI Pro, SPC900NC
KWIQ Guider (QHY5)
ETX-125AT
12" Lightbridge
My Astrophoto Gallery
Astronomical Society of Kansas City
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UniversalMaster
super member
Reged: 11/20/08
Posts: 177
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Quote:
Living in a city, I now image at least 10 times more than I used to because I can do narrowband work much more effectively with the QHY8 than I could with my DSLR.
What is the advantage of the QHY8 over a DSLR for narrow-band, besides lower noise?
Søren
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cvedeler
Carpal Tunnel
Reged: 12/20/05
Posts: 2161
Loc: Scottsdale, AZ
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Quote:
I've found that I need the laptop for so much in order to get good images, needing a laptop for the QHY8 doesn't seem like a huge drawback. Framing for large objects (Western Veil or M31), precise focus, guiding, I can't really manage any of those without a laptop. I often have to look at stretched exposures to assure myself I've got the target at all, and that needs a laptop as well.
The one that's really hard to get around is guiding. How many autoguiders are left that don't require a laptop? I know some of the more expensive CCDs have autoguiding built in, but they're really expensive.
- Gus
Gus I agree 100%. I no longer view having a laptop in the field as a disadvantage when it makes just about everything about getting good results so much easier. In one small package I can autoguide using a $100 CCD camera, assess my framing with much greater ease and precision, assure perfect focus through the night much easier and more precisely, navigate the scope through the sky with "TheSky" instead of using the keypad, plan exposure times of the first target while knowing when the second target will be high enough to start imaging, evaluate the size and orientation of targets in my camera in the field. I find my laptop as indispensable as my mount for imaging these days. I'm also very conscientious of others and my own night vision and so have things in place to eliminate offensive lighting off the laptop.
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Chris Vedeler
Astro-Physics 160EDF
Astro-Physics 900GTO
Q453HR / QHY8 CCD camera
Canon 450XSi
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www.aznightsky.com
Scottsdale, AZ
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Kentari
scholastic sledgehammer
Reged: 11/19/06
Posts: 794
Loc: Belgium
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Quote:
How many autoguiders are left that don't require a laptop? I know some of the more expensive CCDs have autoguiding built in, but they're really expensive.
Not many, and those that do it seem to have their issues... The CCDs which you mention still need a pc/laptop for the autoguiding. There is only a second sensor in the camera housing. But those cameras need a laptop anyway, so that's rather a non-issue.
I would hate to image without my laptop too. Autoguiding is too much of a luxury to miss again... Right now I use a dirt cheap industrial relic laptop ($50) which has 1 USB port (USB 1.1) which is just good for guiding and running Cartes du Ciel.
Next year I will have to upgrade the laptop if I want to control the camera with the laptop as well... I'm thinking to go with a EEE PC or something similar.
Koen
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Darkstar 355 f/5 Dobsonian
Orion UK 8" f/4.5 Newtonian and WO ZS 80 FD on Losmandy GM8
Canon 20D DIY mod with Baader filter
A bunch of lenses: 10-22mm f/3.5-4.5, 17-40mm f/4, 50mm f/1.4, 70-200mm f/2.8, 300mm f/2.8
www.koenvangorp.be
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Gus_Smedstad
Pooh-Bah
Reged: 07/02/06
Posts: 1146
Loc: Boston 42° 16' N 71° 08' W
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Quote:
navigate the scope through the sky with "TheSky" instead of using the keypad
My gosh, I'd forgotten that. Planetarium software is indispensable for me. It takes all the headache out of finding a suitable star for drift alignment under mag-4 skies. I used to hunt for the Western one, and now it's just a matter of finding something suitable in Winstars. And it makes find targets easier, because I can starhop and sync using stars I can't see with the naked eye.
There's also the issue of EQMOD versus the controller. This doesn't affect most people, but pointing was extremely inaccurate using my older hand controller, and with EQMOD, if I take the trouble to sync with a nearby triangle of stars, the target is almost always dead center.
- Gus
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Gus Smedstad image gallery
Orion Atlas 8 EQ-G
Celestron Onyx 80EDF (guiding / widefields).
Orion Starshoot Autoguider
QHY8
Philips SPC900NC
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Nate B.
sage
Reged: 03/08/07
Posts: 282
Loc: Pittsburgh, Pennsylvania
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Quote:
Quote:
Living in a city, I now image at least 10 times more than I used to because I can do narrowband work much more effectively with the QHY8 than I could with my DSLR.
What is the advantage of the QHY8 over a DSLR for narrow-band, besides lower noise?
Søren
I'm able to exposure for much much longer without the huge buildup of thermal noise. I routinely do 30 minutes now instead of the noisy 7 minutes I was doing with my DSLR. Overall my shot to shot signal to noise ratio is much better so I can accomplish a a good looking image with many fewer frames which = less work for me.
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Tak FSQ-106EDX
Pentax 75 EDHF 75mm f/6.7 APO
Apogee Alta U8300 CCD
Orion Atlas EQ-G Mount with EQMOD
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Asturies
sage
Reged: 06/14/07
Posts: 207
Loc: La Mancha, Spain
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Quote:
Fernando,
There is more than just a high quality CCD involved in that Rosette
Yes Bobby, of course, he has a 300mm takahashi if I remember right, but I still don't think you can achieve the same resolution with a DSLR, the bayer matrix is playing against you. (When are they going to make a bayer matrix with SII, OIII & Halfa filters? )
BTW, incredible image for DSLR, he's got close, any link to follow that image and know how he made it?
Roy you have opened a Pandora's Box, it's something like refractor or reflector? I'm enjoying this thred so much.
Regards, Fernando
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LX90 12" with ultrawedge
CG5-GT
Equinox 80mm APO
Mak-Cass 100mm f/14
PST Repaired of rusty objective
Canon EOS 350D
Brand new DBK21 for guiding and planetary
My web translated to English at last!!!
http://perso.wanadoo.es/jfa926/Fernando_Mejido/index.htm
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ccs_hello
Post Laureate
Reged: 07/03/04
Posts: 3298
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Quote:
... achieve the same resolution with a DSLR, the bayer matrix is playing against you...
The above statement is true only when a monochrome CCD (or CMOS) is used. This is independent of what that sensor is ultimated placed into (a DSLR or an astroImager).
But of course no one is making a B&W-only DSLR with just a monochrome imager.
On the other hand, there are astroImagers which use one-shot-color (i.e., Bayer filter array) imagers which has the same OSC related issues.
Back to DSLR vs. astroImager topic:
IMHO, there are always benefits on using purpose-build niche equipment, e.g., monochrome sensor and active-cooling. It's just the cost-benefit tradeoffs. For some, in certain situations, the gap might** be closer than it's perceived to be.
** Two outstanding reasons:
1. (Some of the) later generation sensors are created with better characteristics - S/N and Q/E.
2. Some recent DSLRs are created with desirable features such as Live-Preview and tethered PC-Preview.
My .02
Clear Skies!
ccs_hello
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Samir Kharusi
scholastic sledgehammer
Reged: 06/14/05
Posts: 985
Loc: Oman
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For similar cost and in a fixed setup, I would jump at an astroCCD. AstroCCDs and laptops are power hogs and I did try autoguiding on battery power a few times. The amount of luggage you have to bring along is insane, 50kg in batteries alone! I do not see astroCCDs as somehow having higher resolution. In fact it's only recently (past 12 months?) that you can get an astroCCD that can deliver an A3 print (6+ megapixels) at under $5000. I also believe that for portable use nothing beats a DSLR, currently, coupled up to a camera lens and a mount that delivers long enough subs without autoguiding. My current portable package is even air-travel friendly. But with a set-up that you can leave hooked up, with mains power available, well, an astroCCD comes into its own.
By the way, yardsticks as to sensor sizes are also changing. My preference now is definitely not 35mm format or larger. For decent A3 prints one needs 6+ megapixels. If those pixels can be crammed into a tiny chip, all the better. Current technology seems able to produce nice chip behavior even with the smaller 4 to 5 micron pixels. A smaller chip size enables the use of decent optics with much faster focal ratios and much shorter focal lengths for the same FoV. This simplifies everything, system cost, sub-exposure lengths to get to skyfog-limited regime, size of mount,etc. You lose dynamic range with smaller pixels but that I can easily live with. I think one has to look at what end product one chases, web presentation or what size prints and then work out the system cost. Eg at, say, 1 to 2 arc-sec per pixel (seeing limit at most locations for long exposures), 6+ megapixels, what OTA and sensor will deliver at what cost? On a 35mm format chip I wonder if there is any OTA + flattener that costs much under $8000 is available, capable of A3 prints, and has a reasonable focal ratio (say, faster than f5.6). Once you go to APS size you suddenly open up the Hyperstars, bargains of the decade. The concept of SNR is also changing. Now that multi-megapixel cameras are becoming routine, we need to look not only at SNR at the pixel level (larger pixels better) but also at the (print) presentation level (more megapixels make the spatial SNR better). Seems that with similar chip technology, at A4 or A3 print size, a 15 megapixel sensor will always deliver a better overall SNR than a same-sized sensor with 6 megapixels (i.e. larger pixels), despite all that stuff about better SNR at the pixel level.
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Bored? Peruse my website:
http://www.samirkharusi.net/
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Gary Honis
Vendor-DSLR Mods
Reged: 12/15/04
Posts: 220
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Samir,
I couldn't agree with you more. New Canon 450D bodies can be gotten now between $ 500 and $600 for modification. You can get a new Canon 1000D for even less including a lens. The 450D imaging sensor is 12.2 megapixel with 5.2 micron pixels. I have been getting 20 inch by 30 inch poster size prints of astro images taken with the 450D (Walmart - $16) and the print quality of the images are outstanding. I don't know how much one would have to spend for a commercial CCD camera to get the same results.
Gary Honis
Gallery of 450D images:
http://www.ghonis2.ho8.com/450dgallery.html
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Gary Honis
DSLR Modification Service
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KevinUK
Vendor (DSLR-AstroMod)
Reged: 08/22/07
Posts: 720
Loc: N 51'53 W 00'25
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As someone who modifies DSLRs as a business and is always acutely aware of clients needs, I have found this a most interesting and insightful discussion , and have enjoyed reading peoples personal points of view, and more importantly, personal experiences, out in the field.
Thank you all
Kevin
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DSLR AstroMod
DSLR filter removal and replacement packages
http://www.dslrastromod.co.uk
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7834
Loc: Lexington, SC
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I bought one for $559.00 from Amazon Sunday night. Zero shipping and it arrived yesterday. I tested it this morning and then followed Gary Honis's excellent instructions for modification. I just removed the filter with no replacement for now. I missed one ribbon connector (far upper right on PC board under a second ribbon cable) on putting it back together. Also sneezed and lost one screw. Other than that it works fine. I have to say it's not for the faint of heart or large of hands doing that kind of work. Lots of intricate detail. Neat thing is, looks like all the features of my 20Da are now standard. (Except for an AC battery adapter to prevent constant battery swapping. Haven't located one of those yet.)
A really big thanks to Gary. Excellent work sir. 
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Jerry
Celestron C-11
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Gary Honis
Vendor-DSLR Mods
Reged: 12/15/04
Posts: 220
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Jerry,
Congratulations on the successful mod!
The battery adapter you need for the XSi is the "ACK-E5 AC Power Adapter Kit". You can get it from camera shops and also on ebay.
A hard drive crash caused me to lose a lot of user comments from those following my instructions for the 450D modification. If you can send me a note with any comments you have or recommendations for others, I can add them to the web site. The ribbon cables and connectors keep getting smaller in the newer cameras and good lighting helps to see what you're doing.
Gary Honis 
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Gary Honis
DSLR Modification Service
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 7834
Loc: Lexington, SC
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Lighting is most important Gary.
I did the modification on a large desk. A 12" x 19" sheet of paper taped to the area under the camera made a nice white background critical for locating wayward screws. To the left of the camera I taped two 8" x 10" sheets of paper. On the paper, starting from upper left, I drew a series of boxes down the page. As the screws and parts came out I placed them inside the boxes in sequence. Then penciled in the screen number(from your instruction video) in the box. Easy reference and quick.
A very helpful tool is a magnifier/light cap similar to this one. While helpful, more light would still have been appreciated. The gloves were a very good idea. No smudges on any of the parts when done. Just as stated, the blue glass filter worked out of the frame with thumb pressure and without breaking. I tried several kinds of synthetic gloves and ended up using latex surgical gloves (Walmart). Latex gives a good grip but also fits snugly over the finger tips. Much better control over the small screws.
Overall, not a bad job given your instructions. I would never have attempted it without those clear pictures and sequenced instructions. 
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Jerry
Celestron C-11
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