Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Revolution Imager?

  • Please log in to reply
30 replies to this topic

#1 ajkrishock

ajkrishock

    Explorer 1

  • *****
  • topic starter
  • Posts: 65
  • Joined: 18 Jan 2018
  • Loc: Perseus Arm

Posted 29 July 2019 - 09:35 AM

All,

 

I am considering picking up a revolution imager for my CPC 1100. I have some questions:

 

1. Is the imager threaded for filters?

 

2. I'd like to use my field laptop to capture & display the images. Is this possible? Are there any system requirements I should be aware of?

 

3. What would their "FunStar" accessory provide me? Is it worthwhile?

 

4. I've read on other posts that stacking focal reducers can be as effective as a FunStar. Is this true?

 

5. Can I do live stacking with this imager? What software would I need?

 

6. Is there anything else I should get?

 

 

 

Thanks for your responses


Edited by ajkrishock, 29 July 2019 - 11:25 AM.


#2 ccs_hello

ccs_hello

    Voyager 1

  • *****
  • Posts: 10330
  • Joined: 03 Jul 2004

Posted 29 July 2019 - 04:43 PM

Based on your question 2 and 4, I think you are on (or willing to take on) the current path of "taking advantage of computer power to do many fancy tasks: live stacking, low noise/high gain image acquisition, etc.".

 

In such case, I'd steer you away from Revolution Imager which is an analog video camera improvised for EAA purpose.

It still meet some intended use and purposes but will be award for modern computer-assisted EAA with great benefit.

 

So in short, take the modern/recent CMOS astroimager approach with a PC in tow would be my advice.


  • davidparks likes this

#3 biomedchad

biomedchad

    Viking 1

  • -----
  • Posts: 809
  • Joined: 13 Apr 2009
  • Loc: Galion, Ohio

Posted 29 July 2019 - 05:01 PM

coming back to the hobby after a 3 year break, I went the PC and cmos camera route because I desired to have a more TECH based solution.  the rev imager style of cameras are ok..when you hook up to a pc though they are just the wrong decision.  it takes away from the simplicity of the at the scope viewing experience and complicates it with more cables and software.  you could always do both in the end.  these ccd style cameras are nice when doing outreach and the like..but honestly they offer little comparing you can see the same or better image on a laptop screen with little fuss.  the rev imager cameras have old school menus and are simple but complicated in a strange way because they do things in an odd fashion..they are modified security cameras 


  • rave3c0 likes this

#4 ajkrishock

ajkrishock

    Explorer 1

  • *****
  • topic starter
  • Posts: 65
  • Joined: 18 Jan 2018
  • Loc: Perseus Arm

Posted 30 July 2019 - 07:05 AM

Based on your question 2 and 4, I think you are on (or willing to take on) the current path of "taking advantage of computer power to do many fancy tasks: live stacking, low noise/high gain image acquisition, etc.".

 

In such case, I'd steer you away from Revolution Imager which is an analog video camera improvised for EAA purpose.

It still meet some intended use and purposes but will be award for modern computer-assisted EAA with great benefit.

 

So in short, take the modern/recent CMOS astroimager approach with a PC in tow would be my advice.

Well, don't let my questions fool you. I'm very much new to EAA/astrophotography. I've been a visual observer to this point. I'm interested in the Revolution imager primarily for outreach. I have a refurbed Panasonic Tough Book that I believe has enough horsepower to do anything I need, and I'm also trying to reduce the amount of equipment I have to carry with me. It seems like the revolution imager might be a good way to get my feet wet.



#5 mclewis1

mclewis1

    Thread Killer

  • *****
  • Posts: 19215
  • Joined: 25 Feb 2006
  • Loc: New Brunswick, Canada

Posted 30 July 2019 - 10:00 AM

1) Yes the 1.25" nose piece is threaded for filters. The camera is a C-mount so you can chose from a wide variety of accessories to attach to that C-mount thread.

 

2) Just use the USB frame grabber (OCT sells one, but there are plenty of others on the market) ... most will work fine regardless of how powerful your laptop is. Some older frame grabbers have device drivers that don't work on newer Windows versions so if you are buying used do a little homework first.

 

3) Don't bother with the Funstar, just get a .5x 1.25" focal reducer.

 

5) Get the SharpCap software.


  • Ptarmigan, Ashenshugar and rave3c0 like this

#6 ajkrishock

ajkrishock

    Explorer 1

  • *****
  • topic starter
  • Posts: 65
  • Joined: 18 Jan 2018
  • Loc: Perseus Arm

Posted 30 July 2019 - 01:10 PM

1) Yes the 1.25" nose piece is threaded for filters. The camera is a C-mount so you can chose from a wide variety of accessories to attach to that C-mount thread.

 

2) Just use the USB frame grabber (OCT sells one, but there are plenty of others on the market) ... most will work fine regardless of how powerful your laptop is. Some older frame grabbers have device drivers that don't work on newer Windows versions so if you are buying used do a little homework first.

 

3) Don't bother with the Funstar, just get a .5x 1.25" focal reducer.

 

5) Get the SharpCap software.

Thanks for the guidance.

 

I already have a f/6.3 focal reducer for my SCT. Is that usable? Can I stack two of them together? 



#7 GoFish

GoFish

    Surveyor 1

  • *****
  • Posts: 1644
  • Joined: 30 Nov 2016
  • Loc: Kentucky / Colorado

Posted 30 July 2019 - 01:29 PM

I would like to emphasize advice you’ve already received. 

 

If you are going to use a laptop, do not buy the analog RI. Instead, get a CMOS camera, perhaps ASI224MC. Compared to a modern CMOS camera and SharpCap, the menus and controls on the analog RI camera are archaic and frustrating to use. You can do more, and do it quicker, with the SharpCap/CMOS option. 

 

I suppose the RI might make sense if you absolutely do not want a mount-side computer. Maybe. But I thinks it’s day is past. 



#8 Ashenshugar

Ashenshugar

    Lift Off

  • -----
  • Posts: 3
  • Joined: 24 Jul 2014

Posted 30 July 2019 - 02:04 PM

Well, don't let my questions fool you. I'm very much new to EAA/astrophotography. I've been a visual observer to this point. I'm interested in the Revolution imager primarily for outreach. I have a refurbed Panasonic Tough Book that I believe has enough horsepower to do anything I need, and I'm also trying to reduce the amount of equipment I have to carry with me. It seems like the revolution imager might be a good way to get my feet wet.

Yes it a great way to start ... I have a Rev Imager 2 and I'm mostly a Visual Observer as well. I dont use a laptop in the field I use a small 7" LCD monitor (for Astro club Public nights) or send the signal via wifi to my Tablet which I can record a video or save a picture if I wish.  Its just a nice ~5mm Eyepiece in a way that improves Light polluted viewing and stacks a few secs.  You know... Electronically Assisting your Astronomy.


  • LFORLEESEE and rave3c0 like this

#9 descott12

descott12

    Apollo

  • -----
  • Posts: 1296
  • Joined: 28 Sep 2018
  • Loc: Charlotte, NC

Posted 30 July 2019 - 02:15 PM

Based on your question 2 and 4, I think you are on (or willing to take on) the current path of "taking advantage of computer power to do many fancy tasks: live stacking, low noise/high gain image acquisition, etc.".

 

In such case, I'd steer you away from Revolution Imager which is an analog video camera improvised for EAA purpose.

It still meet some intended use and purposes but will be award for modern computer-assisted EAA with great benefit.

 

So in short, take the modern/recent CMOS astroimager approach with a PC in tow would be my advice.

This is a really important point. The only benefit of the Revolution is that you don't need a computer. If you intend to use a laptop, then it doesn't make alot of sense and you will have a much better experience with a comparably-priced camera (ZWO makes many great ones too choose from). I had a Revolution (for about 2 hours) before I sent it back. I know some people have had good luck with it, but there are many better options in my opinion. For a few specifics, the screen is really small and horrible, the camera is very low res, the menu system is so difficult to use (half the buttons on mine didn't even work) and if I recall correctly, the cables were a jumbled mess which were quite unruly when it was cold and they stiffened. With a typical CMOS camera, you just have one USB cable... a much cleaner affair.

Good luck either way. EAA rocks and  I know you will love it.


  • GoFish likes this

#10 mclewis1

mclewis1

    Thread Killer

  • *****
  • Posts: 19215
  • Joined: 25 Feb 2006
  • Loc: New Brunswick, Canada

Posted 30 July 2019 - 05:03 PM

I already have a f/6.3 focal reducer for my SCT. Is that usable? Can I stack two of them together? 

Yes that focal reducer will be fine. You do need to be aware of it's spacing requirements. Most folks will use a 1.25" visual back and 1.25" diagonal behind the reducer. The camera (whichever one you choose) with a 1.25" nosepiece will just drop into the diagonal. With this setup you won't get the full .63x reduction because the spacing won't be the full 110mm required. It will however work just fine. If you want more reduction you can also stack a .5x reducer with the f6.3 reducer, just place the .5x model on the nosepiece.



#11 ccs_hello

ccs_hello

    Voyager 1

  • *****
  • Posts: 10330
  • Joined: 03 Jul 2004

Posted 30 July 2019 - 08:21 PM

@ OP

I'd say if you are the existing owner of this type of analog video camera (dual-use as an astro video camera) and you have used to the camera menu / do not plan to sell the camera soon, then the next step is what people would call it as work-around path  (** more on this later for the rationale.)

 

If that is not your current situation, and tasks 2 &4 are what you plan to do, then my post #2 stands.  Go straight to CMOS image head + PC solution and leave past behind.

 

==============================

Now why I called it as work-around?

 

Because it is a crude work-around with many cons:

- You have to deal with analog camera's own menu as well as PC side's.  They don't work in-sync or in-concert.

- Lots of video frames are duplicated (all but one should be used) while video-capture on PC is doing lots of wasted work.

- Analog video camera side is handling the low-light side of work (camera DSP is making decision), you can't defeat that.  It is front-end side stacking.

  PC side stacking/processing helps a bit but only a marginal improvement.   When front-end does the work, the original sensor signals is masked by its work, and dilute the rear end benefit significantly (more hidden/extractable signal is thrown away.)

- composite video signal encoding (camera side) and decoding (video capture dongle side) further damages the signal.

- Resolution is limited to 720x480 (480p) resolution.

 

Hope my message is clear.  My intend is not bad-mouth any analog video camera type of usage.  It has been in use for years.

Just trying to say there is path A (analog video) and path B (astroimager as image head with PC does the processing).

 

Path A add the "work-around" is not equal to B.  The gap is not insignificant.



#12 rave3c0

rave3c0

    Sputnik

  • -----
  • Posts: 39
  • Joined: 06 Apr 2017
  • Loc: Browns Valley, CA

Posted 31 July 2019 - 03:57 AM

You've got Lots of good true advice from those more experienced here.

 

My beginner experience with having both the Revolution Imager 2 and a ZWO 224MC (color CMOS) is that the CMOS camera has a lot less wires and a lot more versatility and more resolution. Brand new, they are both about the same price.  You can do everything you have listed with a cmos astro cam and more plus get better images.

 

The RI2 was my first "astro cam", I used it as often as I could for about a year.  The learning curve was easier to get it up and running, but there are just so many wires and battery packs and other limitations that i quickly out grew it.  I'll say this tho, it was great for quick views without the need for a PC, but soon you'll want more. 

 

For me, in hindsight, i should have just started with the cmos 224 or taken the extra money i spent on the RI2 skip the 224 and get a bigger cmos sensor like the 294.



#13 ajkrishock

ajkrishock

    Explorer 1

  • *****
  • topic starter
  • Posts: 65
  • Joined: 18 Jan 2018
  • Loc: Perseus Arm

Posted 31 July 2019 - 06:52 AM

Thanks for all your responses..

 

So, if I forego the Revolution Imager and go to a CMOS camera, such as the ZWO 224MC, what else do I need? One of the things that appeals to me about the Revolution Imager is that it pretty much comes with everything I need to get up and running. With the ZWO, I still need a guide scope and another camera and I have to learn how to guide it, right? My mount is Alt-Az. Do I need an auto align accessory? A wedge? Auto focus accessory?

 

You can see how intimidating all of this is for a noob like me. 



#14 descott12

descott12

    Apollo

  • -----
  • Posts: 1296
  • Joined: 28 Sep 2018
  • Loc: Charlotte, NC

Posted 31 July 2019 - 08:00 AM

Actually it is SO much easier than that.

For EAA with auto-stacking software, you don't need a wedge or polar alignment (although that also works very well) and you don't need a guide scope.

 

A motorized focuser is always a great idea for many reasons but not necessarily specifically for EAA.

 

The camera comes with a tube that will slide right into the back of your focal reducer. Others will hopefully comment but it should come to focus without any additional spacers??

 

That is pretty much all you need. SharpCap is free or almost free for the PRO version (highly recommended). Take some time to read the manual (it is very well written) but there a learning curve. There are tons of previous threads that talk about using it.

 

I would probably recommend a camera with a larger sensor than the 224. It is the camera of choice for planetary stuff but for DSO EAA, a larger sensor is a big help as it allows you to zoom in and also to find your targets more easily.

 

Depending on your resulting FOV you may or may not need to plate solve but that can be automated in SharpCap as well. 

 

Regarding alignment - I just do a very sloppy three-star alignment using SkyPortal and the red dot finder. But I can get away with that as my FOV is so wide and my target is pretty much always in view. But with a narrow FOV, you can't really do that. You may want to consider getting a Star Sense - people seem really like it.


  • rave3c0 likes this

#15 Nicole Sharp

Nicole Sharp

    Surveyor 1

  • -----
  • Posts: 1595
  • Joined: 12 Jun 2018
  • Loc: Cumberland, Maryland, USA

Posted 31 July 2019 - 04:02 PM

I think the answer to all of your questions is yes.  But the main advantage of the Revolution Imager is that it is a stand-alone system.  If you are planning to use a computer, then you would be better off with a USB 3 astrowebcam or a DSLR camera instead.  Note that the Revolution Imager has a very small sensor, so your field of view will be very small, and that the FunStar has severe aberrations.  Also, the Revolution Imager is 480p (standard definition, like what you would find on a VHS tape), so it will appear grainy when viewed on a high-definition monitor.  Your CPC 11 has a huge focal length.  You will not be able to see anything in that OTA on a small-sensor camera except for planets and very small craters or sunspots.  A reducer would help marginally.  The CPC with Revolution Imager would work for the November 2019 Mercury transit, but I would still recommend a high-definition camera instead since you will be able to take advantage of your large aperture with a higher resolution camera.


Edited by Nicole Sharp, 31 July 2019 - 04:05 PM.


#16 donstim

donstim

    Vostok 1

  • -----
  • Posts: 108
  • Joined: 13 Aug 2018
  • Loc: Seattle Area, WA USA

Posted 31 July 2019 - 07:24 PM

I got an RI2 last year bundled with a Celestron Evolution 8 telescope I purchased.  Other dealers were bundling the scope with Celestron eyepiece kits that I really wasn't interested in, but Orange County Telescopes bundled it with the RI2.  I was intrigued by the ideal of EAA, especially with the chance of getting my feet wet essentially for free.  The RI2 comes bundled with a small low resolution monitor, all the cables, a battery, and a 0.5x focal reducer. I ended up getting the USB screen grabber to hook it to my laptop and never used the included monitor.  I used it with Sharpcap on the laptop for live stacking of images rather than the limited "stacking" that can be done by the camera hooked to its own monitor.

 

Based on my use of this system for nearly a year, I agree with the consensus above.  Although the RI2 is advertised as a complete package, implying you need a whole bunch of extra stuff if you buy a different camera, that implication is a bit misleading.  If you already have a laptop that you will be using with the camera as well as a .63x focal reducer, that's about all you'll really need as "extras" for most other camera purchases.  After a year of getting my feet wet with the RI2, I bought an ASI 294MC Pro.  Since this is a cooled camera, I did have to buy a separate battery (a Celestron Lithium Power Pack) in order to run the cooler.  Like you, I already had a 0.63x focal reducer, otherwise, that can potentially be an additional purchase.  I also had a Celestron camera T-adapter, with I can use to directly mount the camera to the focal reducer instead of using the 1.25" adapter supplied with the camera that makes it so you mount the camera just like you would any 1.25" eyepiece.  I also purchased some additional spacers to ensure I had the right back focus distance between the reducer and the camera.

 

Although the RI2 comes with all the necessary cables, the cabling needed is much more extensive than the single USB cable I now use with my CMOS camera. I ended up zip-tying the RI2 cables in several places for cable management and to prevent too much strain on the connector.  Fiddling with the RI2 camera menus to adjust gain and exposure is a bit of a pain as you have to bring up a separate menu, then work your way through the menus to make the changes.  If you forget to close the menu after getting the setting right, then take a snapshot in Sharpcap, well you get a picture of your menu instead of the object you intended to image.  In contrast, ZWO camera menus are integrated into SharpCap, which makes things much much easier.

 

As has been mentioned, you will have a very limited field of view with the RI2, even with the .5x reducer.  I think I stacked the .63x and .5x reducers at times, which improved things somewhat, but still had a limited FOV.  The limited FOV and lengthy process to change gain and exposure made it more difficult for SharpCap to find alignment stars for live stacking. Also, the limited FOV was fine for small objects, but would only show portions of larger objects (even the full Moon is too large).  With the longer focal length of your CPC 1100, the FOV issues will be even worse.  Now, if you are intending to use it primarily for planets, it would be fine.

 

One other thing about the RI2 menus -- the gain and exposure settings are expressed in a way that it is not intuitively obvious once you get slower than 1/50 of a second exposure.  Also, the increments between allowable exposure settings are larger than for the CMOS cameras that can be controlled via SharpCap.

 

I don't know where you got the idea you might need a guide camera, auto-focus, auto-align, or wedge if you went with a different camera, but the "need" for these is no different than for the RI2.  If you a doing short sub-exposures (like 30 seconds or less) and fairly short exposure times (those associated with EAA rather than all-out astrophotography/imaging, your alt-azimuth mount with no guiding should be fine.  I generally do sub-exposures up to 30 seconds and no more than 15 minutes total imaging time (although it would be possible to go a bit longer) with my Evolution 8 alt-azimuth mount coupled with a CMOS camera and SharpCap live stacking.  It doesn't take me more than 10 minutes to manually align using Celeston's CPWI, but as Dave said, a lot of people like StarSense.  I will probably end up getting the Celestron motorized focuser when the 2nd gen version comes out and when CPWI/SharpCap seamlessly connect to it, but for now I am fine with manual focusing.  I do use a Bahtinov mask for focusing, which I recommend you look into no matter what camera you end up with.

 

Good luck!

 

Don



#17 insistent

insistent

    Explorer 1

  • -----
  • Posts: 75
  • Joined: 11 Jan 2019

Posted 01 August 2019 - 07:26 PM

Im pretty new at this too, like many would say the best is to get a refractor telescope, but i didnt do it either, what i use is a Celestron c8 with twin stacked f6.3 reducer, you would need a small sensor camera for this to avoid major vignetting and coma, like my asi224 is fine, another advantage with this camera is its high light sensitivity and ultra low noises, so i can stack at 4-5 seconds only, wich is also easier with worse mounts like my asgt cg5.

My setups is like a jack of all trade at minimal cost and complexity, not great on anything except maybe planets.

Edited by insistent, 01 August 2019 - 07:30 PM.


#18 Nicole Sharp

Nicole Sharp

    Surveyor 1

  • -----
  • Posts: 1595
  • Joined: 12 Jun 2018
  • Loc: Cumberland, Maryland, USA

Posted 01 August 2019 - 07:43 PM

The sensor size of the Revolution Imager 2 is about 8 mm across, so if you want a frame of reference, whatever you would see in an 8-mm eyepiece, is about what you would see in the Revolution Imager: high magnifications and narrow fields of view (nice for Lunar craters and planets but not much else).  A 0.5X focal reducer with the Revolution Imager should then be about equivalent to what you would see in a 17-mm eyepiece: medium magnifications and still somewhat narrow fields of view.  You would need to get the focal length down to about 300 mm or less to see the full disc of Sol or Luna, for which a FunStar or HyperStar in anything larger than a C8 would still have too long of a focal length.  Even something like a little 350/80 GoScope would probably have too long of a focal length for full-disc Lunar imaging (without reduction), so you can see just how small the sensor is for anything other than planetary imaging (a lot of DSOs are much bigger than Sol or Luna).


Edited by Nicole Sharp, 01 August 2019 - 07:48 PM.

  • rave3c0 likes this

#19 ccs_hello

ccs_hello

    Voyager 1

  • *****
  • Posts: 10330
  • Joined: 03 Jul 2004

Posted 01 August 2019 - 08:48 PM

It is 6mm diagonal.



#20 Ptarmigan

Ptarmigan

    Lagopus lagopus

  • *****
  • Posts: 4705
  • Joined: 23 Sep 2004
  • Loc: Arctic

Posted 01 August 2019 - 09:10 PM

Thanks for the guidance.

 

I already have a f/6.3 focal reducer for my SCT. Is that usable? Can I stack two of them together? 

 

I have used 0.63 and 0.5 focal reducers together without much problems with the C9.25. I out the 0.63 reducer at the telescope, then adapter, and use Orion extension tube. Then I put the 0.5 reducer close to the camera. For me, it is around f/275 to f/2.85. There is going to vignetting and coma, but the trade off is shorter exposures, wider views, and less tracking problems.

 

How much one is willing to put up with vignetting and coma is completely up to you.



#21 descott12

descott12

    Apollo

  • -----
  • Posts: 1296
  • Joined: 28 Sep 2018
  • Loc: Charlotte, NC

Posted 02 August 2019 - 06:28 AM

 

 

How much one is willing to put up with vignetting and coma is completely up to you.

Once you get used to SharpCap, you can start using flats and they almost completely eliminate vignetting. They are easy to use and they work very well.


  • Ptarmigan likes this

#22 Thrifty1

Thrifty1

    Mariner 2

  • -----
  • Posts: 231
  • Joined: 24 Feb 2006
  • Loc: Nashville, TN

Posted 02 August 2019 - 09:14 AM

You may also want to ask if there is someone in your area who has a RI2 and you could see it in action.

I’m in the Nashville area and would gladly show anyone interested how mine works.

 

I am using my Canon T3i for more detailed images but I’ve also captured some great images from my RI2. For example, here is the dumbbell nebula taken with the RI2 and my 10” LX200R using SharpCap.  This was one of my first images and I didn’t spend much time on this image so it has some issues. But it was easy to acquire and what I like is I can show similar images on a screen (with or without a computer) when doing a viewing for neighborhood kids.  I purchased a generic Wi-Fi video transmitter so I can show images on an iPad. Multiple people can see the images / pass it around. 

 

I agree the USB cameras have many advantages such as fewer cables and easier camera controls via software when doing more serious imaging. But the RI2 is a great outreach camera when all I want to do is share some images without a computer. 

 

Attached Thumbnails

  • BF92F814-E114-492F-AA42-85A8FF311732.jpeg

  • Ashenshugar and descott12 like this

#23 mclewis1

mclewis1

    Thread Killer

  • *****
  • Posts: 19215
  • Joined: 25 Feb 2006
  • Loc: New Brunswick, Canada

Posted 02 August 2019 - 10:09 AM

It is 6mm diagonal.

Yes, this is the correct size of the type 1/3" sensors (icx673/811 used in the Revolution 1/2 and similar analog video cameras, AR0130, and imx224 in some of the popular CMOS cameras). 

 

8mm is the diagonal size of the type 1/2" sensors - the icx418/428/828 and imx385 sensors. (the 385 sensor is actually a slightly different aspect ratio and is defined as a type 1/1.9" size)


Edited by mclewis1, 02 August 2019 - 01:04 PM.


#24 mclewis1

mclewis1

    Thread Killer

  • *****
  • Posts: 19215
  • Joined: 25 Feb 2006
  • Loc: New Brunswick, Canada

Posted 02 August 2019 - 12:09 PM

The sensor size of the Revolution Imager 2 is about 8 mm across, so if you want a frame of reference, whatever you would see in an 8-mm eyepiece, is about what you would see in the Revolution Imager: high magnifications and narrow fields of view (nice for Lunar craters and planets but not much else).  A 0.5X focal reducer with the Revolution Imager should then be about equivalent to what you would see in a 17-mm eyepiece: medium magnifications and still somewhat narrow fields of view.  You would need to get the focal length down to about 300 mm or less to see the full disc of Sol or Luna, for which a FunStar or HyperStar in anything larger than a C8 would still have too long of a focal length.  Even something like a little 350/80 GoScope would probably have too long of a focal length for full-disc Lunar imaging (without reduction), so you can see just how small the sensor is for anything other than planetary imaging (a lot of DSOs are much bigger than Sol or Luna).

I find the solar and lunar disks well framed at 300mm (and even up to about 350mm) with an IMX224 sensor (same type 1/3" size sensor that is in the Revolution 2). I get this with my AT80ED scope (80mm f7 - 560mm) and a .5x reducer (it's actually working around .6x, so just over 300mm).

 

As for DSOs ... the vast majority are actually smaller than the solar or lunar disks. It's only the big extended stuff (Ha regions, M31, etc.) that you need really short focal lengths to frame with these small sensor cameras. All the major show pieces (M8, M42, etc.) can be framed at around 300mm and virtually everything else actually needs a bit more focal length for a reasonable image scale.



#25 Ptarmigan

Ptarmigan

    Lagopus lagopus

  • *****
  • Posts: 4705
  • Joined: 23 Sep 2004
  • Loc: Arctic

Posted 02 August 2019 - 06:29 PM

Once you get used to SharpCap, you can start using flats and they almost completely eliminate vignetting. They are easy to use and they work very well.

I have also found increasing gains helps reduce vignetting.




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics