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tonyb
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Meade DSI III color and SBIG ST-2000XCM color
      #1991477 - 11/17/07 01:04 PM

It's probably too early to make a comparison as it looks like Meade DSI III color is not widely available, but I had a question. I like the chip size of my SBIG ST-2000XCM; but I dislike having to usually rotate the SBIG to get a good guide star on the guide chip. I also keep getting dust on the imager chip - I assume this is due to the electro-mechanical nature of the SBIG shutter throwing up dust.
Question: I'm considering getting the Meade DSI III color since it looks like there is no shutter and then I will use my DSI II color as the autoguide camera.
Thoughts?
Thx.
Tony.

--------------------
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Phil Jones
sage


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #1991692 - 11/17/07 03:18 PM

When I had the ST-2000, I gave up on using the internal guide chip and went with a separate guiding setup. So guiding with your DSI II is a good idea.

I never had a dust problem. But shooting flats should remedy that for you.

-Phil

--------------------
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darkforce
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Reged: 03/05/07
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #1991952 - 11/17/07 05:28 PM

Hi,

I think, the DSI 3 has the same Chip as the ATIK 16HR or the SXVH9. But the DSI III has no active cooling system and no covered Filterwheel, only the open slider (dust, moiture problems).

So I think the better camera will be the SBIG or the ATIK 16HR and propably the SXVH9

A comparison between the ST2000XM and the SXVH9 is here:

SXVH9 vs. ST2000XM

cs

Immo

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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: darkforce]
      #1992109 - 11/17/07 06:41 PM Attachment (141 downloads)

Unless you're taking really long exposures under dark skies (that counts me out) the passive cooling system of the DSI desgn works fine. As for the exposed slide (and the DSI color cameras don't have one), I suspect this was a cost-control issue (having priced filters wheels) and the slide is easy to cover (see below).

If it were me (and it's not) I'd consider setting up my DSI II as a guider for the SBIG. The color DSI cameras should work fine as guide cameras particuarly if you operate them in monochrome mode.

Link to a brief descrition of my DSI Pro slide cover...

http://mvas.org/phpbb/viewtopic.php?t=161

Picture of the cover...

Attachment

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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havane45
professor emeritus


Reged: 09/28/06
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Phil Jones]
      #1993659 - 11/18/07 02:30 PM

Quote:

When I had the ST-2000, I gave up on using the internal guide chip and went with a separate guiding setup. So guiding with your DSI II is a good idea.

I never had a dust problem. But shooting flats should remedy that for you.

-Phil




The same here, I have a 2000 XCM too (with no dust) and ordered a 99$ dsi for guiding when there was a blow out sale a few weeks ago.

BTW, this old dsi is still sold in France and priced 400 euros ($580) !!!!

Laurent


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russell2002
sage


Reged: 09/10/07
Posts: 211
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: havane45]
      #1993937 - 11/18/07 04:47 PM

Crazy, i have to pay $350 for a dsi in the uk......

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jrcrillyAdministrator
Refractor wienie no more


Reged: 04/30/03
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Phil Jones]
      #1994328 - 11/18/07 08:13 PM

Quote:

When I had the ST-2000, I gave up on using the internal guide chip and went with a separate guiding setup. So guiding with your DSI II is a good idea.




Yup. I quit self-guiding with my ST-8 when I acquired narrowband filters. The DSI Pro does a terrific job. My current SBIG camera doesn't even have the guide chip in it and although I bought it intending to do the upgrade I simply never missed it enough to send the camera in. Of course, I can't use the AO-7 any more but I pretty much never used it anyway.

--------------------
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Battle Cry of Reno
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TeamGS
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jrcrilly]
      #1996452 - 11/19/07 07:22 PM

BTW, with the SXV-H9, the noise is so low, that most users don't even shoot dark frames. Any stray hot pixels are easily removed via sigma combines and hot pixel removal routines during the stacking.

I know I don't shoot darks. (Probably should shoot flats, but I am lazy! )
Gary

--------------------
Celestron 80ED
Losmandy G11
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Starlight Xpress SXV-H9
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tonyb
professor emeritus


Reged: 07/27/05
Posts: 639
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: havane45]
      #1996599 - 11/19/07 08:14 PM

I'm going to still get one of the Meade DSI III color next year - I'm interested to see the differences in captured images. I also took the cover off my ST-2000XCM again to blow dust off the ST-2000XCM Imager chip [again] and used a CCD cleaning swab as there were three dust specks that just would not blow off. The dust spots are gone now and I'm hoping I won't have to take the ST-2000XCM cover off again for dust removal.

--------------------
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Gregk
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #1997978 - 11/20/07 12:34 PM

Tony,

The new DSI has no Cooling at all...Way big difference
all for 1300.00 ....Audotguiding with a seperate scope brings up other issues like Flexure...Interesting discussion.

Greg

--------------------
My Images Here

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Jared
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Reged: 10/11/05
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #1998142 - 11/20/07 01:58 PM

Interesting. I rarely had trouble finding a guide star with my ST2000XCM since the guiding chip didn't need to look through filters. I can see it being a problem when doing emission line imaging with this camera (though I never tried it), but I'm surprised you had problems finding guide stars for ordinary RGB images. In any event, using a separate guide scope and camera should address your concern. Dust, of course, is an issue with virtually any camera, though I would have said that the DSI's with their open air design are more prone to issues here than the ST2000 is. I haven't seen a picture of the DSI III yet. Does it have the same form factor as the previous models?

--------------------
- Jared Willson
  • TV 60iS refractor
  • 80mm SV/LOMO refractor
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Craig
Vendor (Stark Labs)


Reged: 09/16/03
Posts: 762
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2001311 - 11/21/07 09:00 PM

Quote:

Unless you're taking really long exposures under dark skies (that counts me out) the passive cooling system of the DSI desgn works fine.




Works? Sure, but it's not ideal. Any time there is signal there is noise proportional to the signal. It doesn't matter if the signal comes from the target, from the skyglow, or from dark current. Variance is proportional to the mean and more dark current or more skyglow get you more noise without at least also getting your more signal.

The fixed aspects of dark current will be removed by dark subtraction but the noise component can't be and that noise will have a bigger variance if the chip is hotter.

So, I could turn the argument around here and say that we urban astrophotographers who already have skyglow giving one strike against us can hardly afford the foul-tip that noise from an uncooled chip provides.

That could be turned back around to say that from very dark skies, one can pull longer exposures anyway and the lower noise of a cooled design would then make these longer exposures more justified. But, no matter how you slice it, you're adding noise into the image.

Craig

--------------------
Stark Labs Astrophotography software

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tonyb
professor emeritus


Reged: 07/27/05
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Craig]
      #2001400 - 11/21/07 09:39 PM

Hi Craig:

So it sounds like from what you are saying wrt noise, there could be a difference in resulting images between the ST-2000XCM color and the Meade DSI III color. I'm still interested to see how much of a difference and hope to report back in a few months.

Tony.

--------------------
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TeamGS
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Reged: 01/20/04
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #2001751 - 11/22/07 12:59 AM

There would most assuredly be a noticible difference between the two. BTW, with my SXV-H9 (the same chip as the DSI III, but with cooling) I don't need to shoot dark frames, the dark current is that low.

The DSI III is around $1300, and you can get a used SXV-H9 for around $2000.

Regards,

Gary

--------------------
Celestron 80ED
Losmandy G11
NexStar 80
Starlight Xpress SXV-H9
SXV guidehead, ToUcam 840
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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: TeamGS]
      #2002443 - 11/22/07 11:40 AM

“Works? Sure, but it's not ideal.”
Welllll, ideal is in the eyes of the beholder. The Meade DSI’s have been a wonderful match to my equipment, skies, and budget, and for something I can only use a couple of times a month that’s pretty ideal. Maybe if I were set up in an observatory with better equipment under darker skies I’d feel different. Your mileage may vary.

As for signal to noise, that’s been hashed to death. Two very good articles are…

“Finding the Optimal Sub-frame Exposure” by Charles Anstey;

http://www.cloudynights.com/item.php?item_id=1622

“Uncool Imaging Video Cameras and Uncooled Imagers” by John Hoot;

http://68.4.248.85:800/observatory/DSI/UncoolImaging.pdf

As for the DSI III we haven't seen it yet so we're speculating. Personally, I'm saving up to get a DSI Pro III for LRGB imaging and I'm pondering also using my Rebel XTi for color in the same way I sometimes use my DSI to take the color data for my Pro; it'll depend on how hard it is to match the image scale.


Edited by jgraham (11/22/07 11:46 AM)


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TeamGS
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2004468 - 11/23/07 01:49 PM

Good points, John. The DSI's are taking similar images to the top of the line cameras of a few years ago.

It all depends on what your current equipment, goals, and expectations are. Based on the units sold, the DSI is ideal for tons of people.

Gary

--------------------
Celestron 80ED
Losmandy G11
NexStar 80
Starlight Xpress SXV-H9
SXV guidehead, ToUcam 840
http://www.teamgs.org/astrophotography.htm


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schmeah
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Reged: 07/26/05
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: TeamGS]
      #2012665 - 11/27/07 03:52 PM

I was thinking of getting the DSI III as well. I currently image with the DSI Pro II. I've always been envious of the chip size and resolution of the SBIG and other high end cameras. I didn't realize that the DSI III would have the same chip as the SXV-H9. I've already got an ATIK filter wheel and would get the Mogg Outback cooler (approx $275)for the DSI III. So it sounds like it may be getting closer to the higher end cameras for a still very reasonable price.

Derek

--------------------
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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: schmeah]
      #2012694 - 11/27/07 04:08 PM

Derek,

if you're open to other brands you could consider the CCD-labs Q285-M which has the same chip as the III but comes with a built in cooler. Price is similar compared to a III with outback, maybe a little less.

http://www.ccd-labs.com/Qseries/q285.htm

You'll have to wait a little while for the camera but it seems to be a nicer overall package. It would have my preference anyway.

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
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QHY-8, IMG0H, DSI-Pro and DSI cameras
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Craig
Vendor (Stark Labs)


Reged: 09/16/03
Posts: 762
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2021306 - 12/01/07 01:28 PM

Quote:


“Finding the Optimal Sub-frame Exposure” by Charles Anstey;

http://www.cloudynights.com/item.php?item_id=1622





Yes, I know this quite well. I've run through the math and done his calculation for my skies and my camera. BTW, if you use his exact formula (Eq 16), take heed in that the dark current noise isn't included in it where it is included in the simpler approximation. The simpler approximation works well for light-polluted skies, however, and does have the dark current error in there.

With my skies and my camera, cooling does matter (and I run inside the city limits), changing the optimal exposure duration significantly (cutting it in half). For reference, I've measured an ST-2000 XCM's dark current to be 0.017 ADU/sec at -10C and 0.8 ADU/sec at 20C - about a 40-fold difference. While Sony CCDs have lower dark current than Kodak ones, all will follow about a 2x per 6C rate. I've got dark frames from a DSI Pro II at 0C and at 20C and, as expected, there's a heap of difference (of course, key is is the difference large enough to contribute significantly to the noise terms given the skyglow's noise).

I doubt cooling on the DSI III would make no difference with exposures in the 1-5 minute range from urban / suburban skies. If it didn't, you'd not notice a seasonal difference with the camera and many have on the earlier DSIs. You'd also have no market for the Outback cooler.

I'm not trying to bash Meade here or anything. Not at all. They've got a great product and have done wonders for the community and people have made fantastic shots with them. But uncooled Sony CCDs still do have dark current and dark current creates a noise term that subtraction does not pull out and that can be found under typical conditions. That's why I said it wasn't "ideal". I'm not the only one to suggest this. Take Chuck Reese's comments on the Autostar Suite board http://autostarsuite.net/forums/post/6986.aspx

Now, I know you replied in that thread but I also know Chuck knows a thing or two about the DSIs as well and is praising the Outback for dropping his noise levels.

I guess another way of asking this - suppose you could have your DSI cooled for free. No strings attached, no nothing, and no hassles with dew, etc. Would you pass on the deal (or if the camera let you enable / disable the cooler, would you leave it off all the time)? Or would you use it?

Clear skies,

Craig

--------------------
Stark Labs Astrophotography software

Borg 101 ED f/4, C8, and too many cameras to mention


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Nocturnal
Carpal Tunnel


Reged: 09/14/05
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Craig]
      #2021328 - 12/01/07 01:39 PM

No uncooled cameras for me, that's for sure. A few degree temperature difference (even around 0C) and dark frames are useless with the DSI and DSI-Pro. Taking dark frames takes out soo much of the fun of imaging IMO. My next camera will have a thermostatically controlled TEC to keep the temperature steady. I'll still refresh my darks frequently but at least I can do that at any time rather than while the clouds are clear and I'm waiting to collect photons.

As far as dew on cooled cameras goes, I'm not sure why they aren't insulated better. That's how I built my DSI cooler. A small insulated box with a TEC to pull heat out. The insulation reduces the power requirements and reduces dew.

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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Pess
(Title)


Reged: 09/12/07
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2021568 - 12/01/07 04:10 PM

I don't believe the DSI cameras have drivers for the CCDSoft program as of yet.

That means you have to run them off the Envisage software. One extra program to run.

Pesse (I knew I was old when I started getting up at 6:00am instead of going to bed.) Mist


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jgraham
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Reged: 12/02/04
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2022023 - 12/01/07 08:02 PM

“…suppose you could have your DSI cooled for free. No strings attached, no nothing, and no hassles with dew, etc. Would you pass on the deal (or if the camera let you enable / disable the cooler, would you leave it off all the time)? Or would you use it?”

Heh, heh, now that’s a loaded question. I originally wrote a very long response, and then thought better of it.

The short answer is no, I probably wouldn’t use it. I like the DSI Pro. It’s simple, lightweight, does the job and didn’t cost much. The enjoyment per dollar it’s given me has been wonderful. Rather than kludging a cooler onto a system that was designed to operate without one I’d much prefer to buy a new camera that was designed to be cooled. Actually I’ve been taking a hard look at some of the new cameras and I just don’t like the idea of hanging that much iron on my telescope. Please keep in mind, that’s just me. (I once built an astrograph out of balsa wood, a 50mm f/12 Jaegers achromat, a soup can, and the back cut from a Polaroid camera. Using 3000 speed Polaroid film it was a killer deep sky camera for the time.)

Having said that, if I really had a chance to use a free Outback cooler I would be curious enough to mount it up on one of my Pro’s and check it out. It’d be foolish not to. My biggest worry would be the weight and bulk it would add to my camera. Keep in mind I use a variety of mostly low-end telescopes that don’t have the most robust focusers on them. In the absence of a free Outback cooler I could take one of my Pro’s into work with me and chunk it in a cryogenic oven and take a set of darks from say 30C down to -20C and see what they look like. Hmmm, I just installed Envisage on my notebook, this might be worth doing.

Your also question brings up one interesting point; is the DSI design equivalent to a cooled camera with the TEC turned off? I don’t think so. If I recall right the designer of the DSI went to great lengths to reduce the sources of noise as much as possible. Still, it would be interesting to compare cameras using the same CCD; the uncooled DSI Pro and a cooled camera with the cooler turned off at the same ambient air temperature.

Well, I promised to keep this short soooo….

Have fun!

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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Pess
(Title)


Reged: 09/12/07
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2022171 - 12/01/07 09:15 PM

Quote:

Your also question brings up one interesting point; is the DSI design equivalent to a cooled camera with the TEC turned off? I don’t think so. If I recall right the designer of the DSI went to great lengths to reduce the sources of noise as much as possible.




Not exactly. A DSI ccd chip does have a rather large heat sink pressed up against it which facilitates passive heat transfer. This is much better than an actively cooled camera with the TEC turned off but still far, far short of a camera with its TEC turned on.

I wonder though if using a bolt-on TEC cooler for the DSI with a fan, or even just a fan alone, would introduce vibration into the imaging train that would offset the cooling improvement?

Beyond electronic noise the single biggest drawback with the DSI is the problem of taking darkframes. In order to be effective darkframes have to be taken with the camera at the same temperature as the imaging frames were shot. With a temperature regulated camera you can take one set of darkframes for the night with ease..with the DSI..not so much.

Pesse (The 'Dark Knight' was the greatest superhero of all time...and he had not one superpower.) Mist


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2022307 - 12/01/07 10:28 PM

Warning... I sense topics drift...

I take a fresh set of darks right before I start imaging and that usually lasts throughout my imaging session. You can usually tell when the darks need to be re-taken (a process that takes 8-16 minutes depending on how long my subs are). The II and III series cameras have built-in temperature sensors to auotmatically select the best darks once you have a library built-up.

Fan vibration shouldn't be a problem. When the temperature gets above 60F I use a Meade fan and it runs quite smoothly. It has a realy nice set of rubber mounts that are very effective at damping any vibration.

Cooling or not, the bottom line for me is that despite rumors to the contrary my DSI's continue to give the illusion of working quite well. In fact, as near as I can tell all of the CCDs presently available are pretty nice. What a neat time to be an amateur astronomer!

Hmmmm, come to think of it the last time I looked my Rebel XTi doesn't have a TEC on it either... do I sense a trend in my equipment.

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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Craig
Vendor (Stark Labs)


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Posts: 762
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2022758 - 12/02/07 08:33 AM

Quote:

“…suppose you could have your DSI cooled for free. No strings attached, no nothing, and no hassles with dew, etc. Would you pass on the deal (or if the camera let you enable / disable the cooler, would you leave it off all the time)? Or would you use it?”

Heh, heh, now that’s a loaded question. I originally wrote a very long response, and then thought better of it.

The short answer is no, I probably wouldn’t use it. I like the DSI Pro. It’s simple, lightweight, does the job and didn’t cost much. The enjoyment per dollar it’s given me has been wonderful. Rather than kludging a cooler onto a system that was designed to operate without one I’d much prefer to buy a new camera that was designed to be cooled.





Ah, well you've added into the question. The question was a no-cost in any way (hassle, money, dew, size, etc). So just bare it down to cooled vs. uncooled and all else equal. Isolate the question of: is the thermal noise inconsequential or not? Plenty of features on the camera are inconsequential - is this one of them?



Quote:


Your also question brings up one interesting point; is the DSI design equivalent to a cooled camera with the TEC turned off? I don’t think so. If I recall right the designer of the DSI went to great lengths to reduce the sources of noise as much as possible.




The smarmy response would be "And SBIG/SX/FLI/Apogee designers don't go to great lengths trying to reduce the sources of noise as much as possible?" Remove the smarmyness (word?) and we're left with the point that all designers try to reduce the noise as much as possible given the cost constraints. The read noise on the DSIs is excellent and you're right in that a cooled camera w/o the TEC on won't do as well as the DSI design. The TECs themselves aren't as thermally conductive as a block of aluminum, so the passive cooling is more effective on the DSI than on cooled cams with the TEC off. That's why I was referring to chip temp, not ambient.

That said, it's not like the passive system is 100% efficient and can keep the chip at ambient much less at 35C below ambient. One could simulate a perfect passive by just setting the temp setpoint to the ambient temp. Anyway, it all comes down to CCD temp and the DSIs will let you read that off.

As for the weight, adding a TEC doesn't add much at all. The power supply for it can be a bit, but needn't always be. The DSLR (APS) sized Q8 is only 1.5 lbs -- less than a number of Televue eyepieces.

Craig

--------------------
Stark Labs Astrophotography software

Borg 101 ED f/4, C8, and too many cameras to mention


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Craig
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2022782 - 12/02/07 08:55 AM

Quote:


Cooling or not, the bottom line for me is that despite rumors to the contrary my DSI's continue to give the illusion of working quite well. In fact, as near as I can tell all of the CCDs presently available are pretty nice. What a neat time to be an amateur astronomer!

Hmmmm, come to think of it the last time I looked my Rebel XTi doesn't have a TEC on it either... do I sense a trend in my equipment.




Just to make sure we don't misunderstand each other... I gave a talk this summer at MAIC 2007 on "Affordable Astrophotography" and recommended the Canon Rebel XT and DSI II Pro along with the Orion DSCI. I even showed a side-by-side with $1700 setup vs. a >$50k setup on M51 with the Rebel XT shot (8" Newt, ASGT) spanking the ultra high-end setup. In the hands of a good imager, they can do very well.

The DSI II (and hopefully III) series are solid cams that have taken some great shots. DSLRs have taken some stunning shots. But, they won't go as deep as cooled one-shot CCDs. If I had the choice between a cooled and an uncooled version, I'd take the cooled any day (or night, or at least night that's not below freezing anyway). Thermal noise when uncooled drops SNR. So does light pollution, so does smaller apertures.

Craig

--------------------
Stark Labs Astrophotography software

Borg 101 ED f/4, C8, and too many cameras to mention


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Pess
(Title)


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2022793 - 12/02/07 09:04 AM

Quote:

Hmmmm, come to think of it the last time I looked my Rebel XTi doesn't have a TEC on it either... do I sense a trend in my equipment.




You're in Dayton, I'm up in Toledo. This time of year...

Pesse ( We no need no stink'n TEC cooler! ) Mist

Edited by Pess (12/02/07 09:39 AM)


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2022832 - 12/02/07 09:42 AM Attachment (122 downloads)

Pesse, heh, heh, yep we've got all this natural cooling (see below)

Craig; Under my observing conditions with my equipment the thermal noise in the original DSI and DSI Pro is not an issue, zero, nadda, zipperoo and I've heard the II's are even better. I've been threatening for years to take my equipment out under dark skies to see what it can really do and maybe then I'll long for Maxwell's demon. In the mean time what I'm looking forward to in the Pro III is the same wonderful simplicity and a much larger chip (and an IDAS LPS filter).

I don't know who said it first but I'd love to know so I can credit them on the list of wise sayings that I have taped to my door at work; "Better is the worst enemy of good enough." I've got a really good story that goes along with that, but that's for another thread.

I just hope Tony got his question answered!

Now for a picture of my naturally cooled DSI Pro II...

Attachment

Edited by jgraham (12/02/07 09:48 AM)


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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2022897 - 12/02/07 10:26 AM

The counter of "Better is the worst enemy of good enough." is "make things as simple as possible but no simpler". To me the DSIs are too simple. Dark frames are too dependent on temperature and I don't dare to stretch them for different exposures either. Maybe I have bad cameras and you have good ones. My Pro has terrible interlacing artifacts and I'm not sure this can be compensated for with dark frames. The color camera works better but the aforementioned dark current issues plague mine as well. Even going from 1C to -1C during a session will make darks sub optimal and you end up with streaks that need fixing.

The III promises to be a good camera, the beta images sure looked great. But I would rather spend a few hundred more and buy either the opticstar or ccd-lab (QHY) camera with the same chip but TEC cooled.

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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Pess
(Title)


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2022992 - 12/02/07 11:17 AM

Quote:

The III promises to be a good camera, the beta images sure looked great. But I would rather spend a few hundred more and buy either the opticstar or ccd-lab (QHY) camera with the same chip but TEC cooled.




My experience has been that if you are real careful with your darks you can get good results with the DSI II. The trouble is getting the 'good' darks. I start imaging at 8pm and stop around 1am and I may see a 10 degree swing this time of year!

Compound that with a 10 minute requirement for darks for the DSi per temperature point and...well, you get the general idea.

I now image with a SBIG ST2000. With TEC regulation and auto darkframe acquirement I can concentrate on the imaging aspects. Since the camera is held at one temp point all night I just need the one darkframe per exposure setting and that the SBIG does for me.

Pesse (I have to take my laptop in for service. The Hibernate function only works in the fall.) Mist


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2023238 - 12/02/07 01:25 PM Attachment (102 downloads)

"make things as simple as possible but no simpler"

I like that.

Below is the system I learned CCD imaging with. It was an absolute blast to use and represented a wonderful year of discovery and pushing the edge of what you can do with limited resources.

Attachment

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2023266 - 12/02/07 01:38 PM

The ST-2000 can take darks without covering the scope? Sweet! I'll need to read up on that camera. I didn't realize it came with an internal filter wheel.

I am pretty sure the DSI-II is leaps ahead of the I but temperature drift during the night is a problem like with the previous model. The new Envisage version *should* be able to apply different darks for different temperatures provided you have them 'in stock'. I haven't seen this in action with the DSI-II though.

I think a good proportion of folks that have good success with the DSI camera use an outback cooler or some other form of thermostatically controlled cooling.

Best,

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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Galaxyhunter
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2023335 - 12/02/07 02:14 PM

Quote:

The ST-2000 can take darks without covering the scope? Sweet! I'll need to read up on that camera. I didn't realize it came with an internal filter wheel.




Slight Clarification, ST2000 has an internal shutter, not a filter wheel.

--------------------
Carl

Observatory temperature experiment

Weather Station @ Hawkeye Observatory

My lousy skies at Hawkeye Observatory H52


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AlanT
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2023397 - 12/02/07 02:43 PM

I might be just lazy, but for me having to to take darks every session (or twice a session) with my DSI Pro was annoying. Being miserly, I did a "home brew" addition of a TEC cooler and it drops the noise level enough that I only have to take new darks if there is a very large change in temperature. (I posted how I made the mods here: my humble homepage )

I've been struggling with getting a new camera, and am completely undecided.
- The DSIs are really convenient in that you don't neet the extra power for the TEC, Envisage really does a pretty good job of handling the dark noise, and from my back yard light pollution dominates anyway, BUT,
- If I'm spending over a grand for a camera, wouldn't I want one that can do great with long exposures under good dark skies?

If the price of the DSI 3 wasn't so good, the decision would be a lot easier

--------------------
al

Meade 80mm APO
Celestron 6" SCT
CGE, GM-8, & CG-5 GT
ST-4000xcm, ST-2000xcm, DSI Pro II, DSI Pro
( www.alberts-astro.com/astro )


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: AlanT]
      #2023596 - 12/02/07 04:37 PM

The bigget problem I have with the DSI Pro III is the price. I'll have to think long and hard before biting that bullet, fortunately they aren't shipping yet (I think) so it's a non-problem at the moment. Even at list price the Pro was quite a value. I bought one when they were new and another during the fire sale.

Neat mod by the way. You might visit the Outback Cooler site and see how Steve seals the Pro. If it were me (and it's not) I'd see if I could squeeze a little silica gel pack inside the case somewhere to scavenge the last bit of moisture once the case were sealed.

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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AlanT
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2023756 - 12/02/07 05:49 PM

Yup I thought about it a lot. However I decided the back is just too hard to seal, so I chose to only try and seal the front of the CCD. So far it's working (fingers crossed).

I see that OPT is now showing the DSI 3 as "In Stock". Now there isn't a crutch to help me avoid making a decision...... well, maybe I'll wait for more reviews.

--------------------
al

Meade 80mm APO
Celestron 6" SCT
CGE, GM-8, & CG-5 GT
ST-4000xcm, ST-2000xcm, DSI Pro II, DSI Pro
( www.alberts-astro.com/astro )


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Pess
(Title)


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2023895 - 12/02/07 06:44 PM

Quote:

Neat mod by the way. You might visit the Outback Cooler site and see how Steve seals the Pro. If it were me (and it's not) I'd see if I could squeeze a little silica gel pack inside the case somewhere to scavenge the last bit of moisture once the case were sealed.




Yes, that's another problem. If you can't get some dessicate in there and get a tight seal you defeat the purpose of the TEC cooling. Any meaningful temperature drop of the CCD imaging chip will allow condensation to freeze upon it.

Actively cooled cameras usually have a built in dessicate plug that can be removed and recharged in an oven. The DSI camera will have to be disassembled periodically to replace or recharge the dessicate as you can't possibly seal the camera perfectly and moisture will leak in over time.

I looked into it and the cost/benefit ratio of adding TEC cooling to a DSI camera didn't seem worth the effort. For that money just buy a used SBIG or something instead of putting a 'thing on a thing'.

Pesse (I stand my wife next to the scope and say her outfit makes her look fat.....things cool down real quick then!) Mist

Edited by Pess (12/02/07 06:45 PM)


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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Galaxyhunter]
      #2024004 - 12/02/07 07:37 PM

Ah. Still very useful though.

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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lawrie
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Pess]
      #2024029 - 12/02/07 07:45 PM

Well, after reading this thread, one thought comes to mind,
The DSI line of imagers have come a long way to be compared to SBIG's and SXV lines of cameras.
If I was to spend that kind of money, I would look at a cooled camera also. A lot of people have seen really good images with the Pro II, but if you read further, they have outfitted them with the Outback tech cooler. The DSI Pro III is Meades start into more serious imagers (as they follow there customers level of competence in astrophotography), I think there mistake is not having the option for cooling.

--------------------
Clear Skies
Lawrie

9.25 Edge/Hyperstar
NP 101is
WO 80fd
G-11/Atlas
ST 8300




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schmeah
scholastic sledgehammer


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2024125 - 12/02/07 08:18 PM Attachment (105 downloads)

While in theory the darks temp / exposure time library used by the DSI II series and envisage is a great idea, in practice I haven't found it to be all that useful. The darks that I took last year are essentially worthless this year even when matched precisely for temp and time. I posted an example below of a stacked image with such poorly matched darks coupled with 6 hours worth of drift. You can see the thermal noise is pretty significant and the darks library was useless. What I do now is use an external fan to lower the camera temp by about 3 degrees at the beginning of a session, take darks and set the dark temps variance limit to 3 deg. So even if the temp drops by 5-6 degrees C overnight I'm still fine and the dark subtractions are excellent with a single set, so long as it's taken that night. I do plan on getting the outback cooler though if I get the DSI III. Derek

Attachment

--------------------
- Derek
10"LX200R, SVR90T
QSI 540 wsg, DSI Pro III, SX Lodestar
http://www.pbase.com/dsantiago


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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: schmeah]
      #2024173 - 12/02/07 08:33 PM

Darks age for sure. That's why I want a camera with an active cooler that chills the camera to the point where dark current is very low and only a few darks need to be taken to have a statistically significant average. The larger the energy in the dark signal (higher temps) the larger the noise hence the need to take more darks to average out the noise.

I don't really see the point of getting a III and an outback unless you need the camera *now*. CCD-labs takes a while to ship. Opticstar is in the UK and I'm not sure the camera is available yet. On the plus side both cameras come with Nebulosity which is more capable than Envisage. The CCD-labs camera is argon purged so it's dry inside. Not sure how the opticstar deals with that.

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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tonyb
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Nocturnal]
      #2024181 - 12/02/07 08:36 PM

My Meade DSI III color arrived yesterday. Once we get some clear skies, I'll be trying it out. I'm still keeping my SBIG ST-2000XCM

--------------------
* Blog
* Celestron C9.25" Carbon SCT
* WO FLT 110 Refractor.
* Atlas EQ-G mount.
* QHY8Pro color CCD.
* Imaging Source DBK 31AU03.AS color webcam
* Starlight Xpress Lodestar Autoguider
* PHDGuiding + Orion Deluxe OAG
* IC Capture.AS
* Registax/CCDSoft/Photoshop CS6


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: schmeah]
      #2024188 - 12/02/07 08:39 PM

One thing I did early-on with my DSI Pro is I built up a library of darks taken at different temperatures. If I needed a new set of darks because of a temperature change I'd just copy the appropriate darks over to the darks folder. It worked okay, but to be honest I found if easier just to take a fresh set. My standard exposure is 30 seconds so a complete set of 1-30 second darks only takes 8 minutes, and 1-60 seconds takes about 17 minutes; can you say bio-break?

I've been looking up all these cameras that are 'better' and more 'ideal' and I gotta tell you if I spent that kind of money on a camera I'm sure the images would be great, it's the divorce I'd have a problem with (assuming I'd regain consciousness). Even though they're not for me, it's sooo neat seeing such wonderful equipment being offered, and for what you're getting they really are 'relatively' affordable. Not that long ago we paid over $20,000 for a 512 channel cooled, purged, linear diode array (essenitally a single-line CCD) with a computer interface. The parallel interface was a nightmare to write software for, but that's another story.

Derek; an easy way to deal with noise like that is to save all of your uncombined source images as FITS, align them in ASIP, then do a median combine. You'll find the little bit of tracking error actualy works in your favor as all those hot and cold pixels will disappear. I 'discovered' this trick while imaging faint comets.

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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AlanT
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: lawrie]
      #2024211 - 12/02/07 08:46 PM

Quote:

...... The DSI Pro III is Meades start into more serious imagers (as they follow there customers level of competence in astrophotography), I think there mistake is not having the option for cooling.




My noobienes will show here, but I think you're right with that last bit.

For all it's wonkyness, I actually like the Envisage software [duck]. I like how it subtracts darks on the fly and builds the image on the screen as you go (does any other capture sofware do this?). I can always reprocess the data later with other software.

For me it is a pretty good reason to stay with the DSI line. So if Meade offered their camera in a cooled version, unless there was some other serious deficiency, I'd dive on it... even for more moollah.

I'm probably going to buy a cooled camera as my next, but I'm not looking forward to learning (and possibly buying) new software.

--------------------
al

Meade 80mm APO
Celestron 6" SCT
CGE, GM-8, & CG-5 GT
ST-4000xcm, ST-2000xcm, DSI Pro II, DSI Pro
( www.alberts-astro.com/astro )


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Nocturnal
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: AlanT]
      #2024247 - 12/02/07 08:58 PM

Hi,

I think Envisage has its merits and problems. Building the image on screen is a nice gimmick but it hardly ever yields the best image. On the fly dark subtraction is also nice but if your darks are poor (easy to happen) your lights are ruined forever. I prefer to take raws and do dark subtraction separately.

On the other hand, if it works well for you who am I to suggest alternatives :-)

Best,

Sander

--------------------
Best,

Sander


Edge HD 11 + HyperStar3 on Takahashi EM-400
William Optics M110 With FR-III/TRF-2008
QHY-8, IMG0H, DSI-Pro and DSI cameras
watec 802h video camera with KIWI OSD for occultations

Astro stuff:
http://www.carpephoton.com
http://www.tungstentech.com
My Astro Photos


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schmeah
scholastic sledgehammer


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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2024249 - 12/02/07 09:00 PM Attachment (232 downloads)

Hi John. You're right ASIP median combine works pretty well as does sigma combine.I did just that do get to the image below. Unfortunately I think you lose some fine detail in the nebula when using either of these methods. Sander, I think perhaps I've become so comfortable with envisage (guiding etc) and the DSIs that if I think I can get a comparable result by adding an Outback, it'll be less stressful to go with the III than with another camera / software where I'd again be starting at the bottom of the learning curve. Maybe that's why I haven't sparked up the Hutech modified 400D Xti that I've got sitting around. BTW John, I loved your M42 with your xti. Why aren't you using it more? Derek

Attachment

--------------------
- Derek
10"LX200R, SVR90T
QSI 540 wsg, DSI Pro III, SX Lodestar
http://www.pbase.com/dsantiago


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jgraham
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: schmeah]
      #2024466 - 12/02/07 10:55 PM

Wow, that's a beautiful image! I noticed the images were a tad softer using median combine, but I found I had fewer artifacts than using drizzle or averaging. Now that I'm autoguiding that night change (I haven't tried autoguiding while imaging with my Pro yet).

As for my XTi, that's an easy one, it's called Ohio weather! Actually, my XTi has been occupying nearly all my imaging time for the past couple of months (that and Comet Holmes). I set up autoguiding specificaly for the XTi since it became clear fairly quickly I needed longer exposures using this camera. However, I've got a growin list of small targets that I want to tackle with my Pro. Hopefully, once winter settles in the weather will clear up a bit.

Tony, congrats on the new camera!

Have fun!

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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blueman
Vendor Blue Sky Accessories


Reged: 07/20/07
Posts: 4303
Loc: California
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2031708 - 12/06/07 12:13 AM

The DSI III Pro with an Outback Razorback cooler for $265 and $16 shipping would still be under $1600 and that is pretty good. Especially if you figure the Outback is controlled cooling unlike some of the other cameras that just cool by 30 degrees below ambient.
I am considering that deal myself.
Blueman

--------------------
14.5" Starmaster with ServoCat and Argo Navis
1966 Unitron 4" Model 152 EQ
Tec 140
TV NP101 f/5.4 APO Telvue .8 Focal Reducer
FLI ML8300 and CFW-2-7 filter wheel
Astrodon Gen2 RGBL 2" filters
Baader 2" Narrow Band Filters
Borg 50mm Guide Scope/ATIK Titan Guide Camera
AstroPhysics AP900
Losmandy GM-8 Gemini


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garymck
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Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: blueman]
      #2040796 - 12/10/07 06:46 AM

I wouldn't buy an outback cooler.

I had one on my DSI 1 Pro.

With the outback running my bias frames showed random variations. I sent the following email:

"have just fitted an Outback Cooler to my DSI Pro.

There seems to be a problem with electronic noise coming from it.

I am unable to take accurate bias frames with the cooler powered.

For example, with the cooler unpowered my bias frames vary by about 3-5 counts per exposure, however as soon as I power up the cooler, the bias frames vary randomly over a factor of 100-150 counts.

This random noise means I am unable to take accurate bias or dark frames, and my images are "grainy" as a result.

Is there anything likely to be wrong with my cooler, or any mod that I can do to reduce this interference?

Hope you can help,"

I did not get a reply. Obviously no vendor support.

my 2 cents
cheers
Gary


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donsinger1
sage


Reged: 10/28/07
Posts: 307
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: garymck]
      #2041568 - 12/10/07 02:44 PM

Wonder if anyone else has had this problem?

Don

--------------------
Fun Stuff:)
Portland, OR


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jgraham
Postmaster


Reged: 12/02/04
Posts: 11575
Loc: Dayton, Ohio
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: donsinger1]
      #2041631 - 12/10/07 03:09 PM

It's the first I've heard of a problem with an Outback. There are several users that have them over on AutostarSuite.net.

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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Dennis Sakva
Pooh-Bah


Reged: 10/19/04
Posts: 1432
Loc: Kiev, Ukraine
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: jgraham]
      #2043061 - 12/11/07 02:37 AM

BTW Sony chips are so much less noisier than Kodak chips used by SBIG. And cooled Sony chips (est 285) are fantastic. Dark frames are making picture worse rather than better (as dark frame substruction ADDs random noise while removing periodic

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idahoman
professor emeritus


Reged: 11/25/05
Posts: 679
Loc: Idaho, USA
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Dennis Sakva]
      #2044628 - 12/11/07 07:53 PM

Maybe it is just me, but I tried guiding with a DSI Pro and imaging with a DSI Pro. Never had much luck. Now I have the ST-2000XCM, and everything is so much easier, and hence my chances at success are much better. With the regulated TEC, I manage my dark frames better (granted -- the Pro II and Pro III have internal temperature measurement and the Pro did not). The internal shutter makes life easier. And, the autoguiding is such that I don't have to worry about differential flexure, focusing two scopes, and focal length matching issues. Plus, for some reason, calibrating my guiding with the ST-2000 was easier. I think this was due to the ST-2000 having a ST-4 output built in. With the DSI Pro, I had to use a GPUSB. Anyway, my opinion is, maybe given a lot more effort, I could have gotten my original setup working better. And, the ST-2000XCM was substantially more money. But, the SBIG worked out better for me.

--------------------
A Guy at the Cosmic Debris Observatory, Idaho

43° 31' N 112° 4' W
4780 ft elevation


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blueman
Vendor Blue Sky Accessories


Reged: 07/20/07
Posts: 4303
Loc: California
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: Craig]
      #2045263 - 12/12/07 03:17 AM Attachment (220 downloads)

I just purchased the DSI Pro III and have been using a DSI Pro II for a while. I get great photos with the DSI II and I expect to get great ones with the DSI III too. Plus, I will receive the Outback Cooler for it the first of the year which will allow me to select a temp from -10c to +20c in 5°c increments which will surely make it work very well indeed.
This is an example of the photos I take with the DSI II.

Attachment

--------------------
14.5" Starmaster with ServoCat and Argo Navis
1966 Unitron 4" Model 152 EQ
Tec 140
TV NP101 f/5.4 APO Telvue .8 Focal Reducer
FLI ML8300 and CFW-2-7 filter wheel
Astrodon Gen2 RGBL 2" filters
Baader 2" Narrow Band Filters
Borg 50mm Guide Scope/ATIK Titan Guide Camera
AstroPhysics AP900
Losmandy GM-8 Gemini


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msibleyj
newbie


Reged: 01/02/07
Posts: 2
Loc: San Antonio, TX
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: donsinger1]
      #2130215 - 01/18/08 09:57 PM

I had the same problem with the Outback with my darks. With the cooler on I got jumping pixels in random patterns. Sent the frames to the manufacturer and he said it was normal. However, it rendered my darks unusable, as well as any frames I took with the cooler running. Am currently working on my own peltier cooler--and am getting no jumping hot pixels.

Mark J


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lineman_16735
Tak-o-holic


Reged: 12/04/04
Posts: 3118
Loc: Central PA
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: msibleyj]
      #2130374 - 01/18/08 11:24 PM

I had the same issue with the outback. Although at the time I didn't know the cooler was the problem, I thought it was the camera.

--------------------
Chris


X-Astronomer


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jgraham
Postmaster


Reged: 12/02/04
Posts: 11575
Loc: Dayton, Ohio
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: lineman_16735]
      #2130386 - 01/18/08 11:32 PM

Hmmm, I wonder if a median combine would reduce the problem. I use median combine with my DSI Pro and it does a great job reducing random defects in my source images.

--------------------
-John

The best advice on imaging I've ever been given... don't forget to look!


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tonyb
professor emeritus


Reged: 07/27/05
Posts: 639
Loc: WA, USA
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #2404863 - 05/18/08 10:37 PM Attachment (198 downloads)

These were my first two images from the Meade DSI-III. They are each 24x2mins subs in 2/5 seeing 5.15.08. Pshop processed with curves, levels, slight star bloat, background sky smoothing and unsharp mask.

Attachment

--------------------
* Blog
* Celestron C9.25" Carbon SCT
* WO FLT 110 Refractor.
* Atlas EQ-G mount.
* QHY8Pro color CCD.
* Imaging Source DBK 31AU03.AS color webcam
* Starlight Xpress Lodestar Autoguider
* PHDGuiding + Orion Deluxe OAG
* IC Capture.AS
* Registax/CCDSoft/Photoshop CS6


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justabob
Carpal Tunnel


Reged: 05/05/07
Posts: 1899
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: tonyb]
      #2406235 - 05/19/08 03:03 PM

Very nice! What scope fl are you using? How much were they cropped?

--------------------
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
SBIG ST8300c
DSI PRO II



Bob



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tonyb
professor emeritus


Reged: 07/27/05
Posts: 639
Loc: WA, USA
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: justabob]
      #2406251 - 05/19/08 03:11 PM

I took these with my Celestron SCT 9.25" carbon. FL~2350mm. No cropping. I'm going to start a new thread in CCD imaging on this forum so others can see.

Many thanks.

Tony.

--------------------
* Blog
* Celestron C9.25" Carbon SCT
* WO FLT 110 Refractor.
* Atlas EQ-G mount.
* QHY8Pro color CCD.
* Imaging Source DBK 31AU03.AS color webcam
* Starlight Xpress Lodestar Autoguider
* PHDGuiding + Orion Deluxe OAG
* IC Capture.AS
* Registax/CCDSoft/Photoshop CS6


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blueman
Vendor Blue Sky Accessories


Reged: 07/20/07
Posts: 4303
Loc: California
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: darkforce]
      #2408565 - 05/20/08 02:42 PM Attachment (139 downloads)

I have the DSI III Pro, with an Outback Razorback Cooler and Atik filter wheel. Words very well and cost about $1800 total equipted this way.
This picture shows it with the cooler and wheel and a foam insulation block that I made for it, to keep the cold inside the case.
Blueman

Attachment

--------------------
14.5" Starmaster with ServoCat and Argo Navis
1966 Unitron 4" Model 152 EQ
Tec 140
TV NP101 f/5.4 APO Telvue .8 Focal Reducer
FLI ML8300 and CFW-2-7 filter wheel
Astrodon Gen2 RGBL 2" filters
Baader 2" Narrow Band Filters
Borg 50mm Guide Scope/ATIK Titan Guide Camera
AstroPhysics AP900
Losmandy GM-8 Gemini


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blueman
Vendor Blue Sky Accessories


Reged: 07/20/07
Posts: 4303
Loc: California
Re: Meade DSI III color and SBIG ST-2000XCM color new [Re: blueman]
      #2408573 - 05/20/08 02:47 PM

Here is a shot of M13 that I took with this camera to compare it to others, like the S-big.
Full res and size
http://www.astrophotogallery.org/showphoto.php/photo/291
Blueman

--------------------
14.5" Starmaster with ServoCat and Argo Navis
1966 Unitron 4" Model 152 EQ
Tec 140
TV NP101 f/5.4 APO Telvue .8 Focal Reducer
FLI ML8300 and CFW-2-7 filter wheel
Astrodon Gen2 RGBL 2" filters
Baader 2" Narrow Band Filters
Borg 50mm Guide Scope/ATIK Titan Guide Camera
AstroPhysics AP900
Losmandy GM-8 Gemini


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