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Help with Jupiter photos with a C11

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#1 Kevdog

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Posted 07 December 2012 - 05:20 PM

I'm using a C11 on the standard fork for now. I have a wedge, but haven't set it up yet (just got the scope last Tuesday).

I was out Wed night trying my hand at Jupiter with the new scope and I think I should be able to get better results than what I'm getting.

Camera:
Olympus E-M5 (16mp m4/3 sensor, which is half the size of a full frame sensor) with T-Adapter. So at prime focus it's like a 20mm eyepiece, with the barlow in it's like a 10mm eyepiece.

Here's Jupiter without the barlow and cropped:
Posted Image

Jupiter with the barlow and cropped:
Posted Image

And for comparisons, here's the Orion nebula without the barlow on the same night:
Posted Image

It's sharper through the eyepiece than the images I'm getting. It also seems sharper on the screen versus what I'm capturing in the image.

I took them as RAW and processed them manually.

I tried different ISOs from 400 up to 6400 with varying shutter speeds, but still can't seem to get as sharp an image as I think I should.

Any ideas, hints, etc?

I'm thinking of getting a Crayford focuser to help with fine focusing both for imaging and for visual. Might also get a flip mirror to help with imaging.

(Edit: Forgot to mention that I did take video, but it was AVCHD in .mov format which Registax couldn't read. I need to try again in MJPEG format which writes an avi, but reduces the resolution.)

Thanks!

#2 oldstargazer

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Posted 08 December 2012 - 09:10 AM

I used my canon t3i to take some of jupiter and set the iso high so I could use the highest shutter speed possible and got some pretty good images. It looks like the one of Orion is either slightly out of focus or your collimation is slightly off. I use live view and the 5x setting to get a sharp focus on a star before taking a shot and if I move to a different part of the sky I have to do that again because I always get mirror shift when it changes angles.

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#3 Maverick199

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Posted 08 December 2012 - 09:21 AM

Those are pretty decent images of Jupiter for a start. What you need to do is shoot a video and then stack the images with Registax. Shoot for about a minute in .avi format or convert the movie into .avi format with freeware like VirtualDub. A Neximage or even a DSLR with crop movie mode helps in obtaining videos.

#4 Kevdog

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Posted 11 December 2012 - 02:53 PM

I'll have to take some time and stack them. I'll have to get VirtualDub to convert it to avi first.

Looks like I also need a crayford focuser and possible a focusing mask to help make focusing more precise?

#5 Kevdog

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Posted 16 December 2012 - 02:28 AM

Here's the stacked version from that same night. It does look better, but how do I get more detail out of it?

Focusing?
Seeing?
Better camera?
Better tracking/wedge use?

Posted Image

#6 Tapio

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Posted 16 December 2012 - 02:40 AM

Not bad at all.
How many frames did you stack and did you use wavelets (in Registax) ?

#7 Kevdog

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Posted 16 December 2012 - 10:22 AM

Looks like it says 28 frames. And no I didn't use wavelets. Not even sure how yet! (Only 2nd image done in Registax :D )

#8 Kevdog

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Posted 16 December 2012 - 10:29 AM

Here's a try with wavelets and a stretched histogram.

Posted Image

#9 RedLionNJ

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Posted 16 December 2012 - 12:50 PM

I'm not too familiar with that particular camera, but the guidelines for applying it to planetary photography should be similar to those for the more popular Canon range:

1. Capture as many frames as you can in a short time - this essentially means using a video mode, if the camera has one. You need a LOT of frames to combat the noise inherent in DSLR short, low-light exposures. When I say a lot, I mean ideally a thousand or more.

2. If using a video mode, try to pick the one with the least compression and highest frame rate. For example, the Canon 60D has a mode where it will use only the middle 640 x 480 pixels, but will record at 60fps.

3. Try to get a large image scale on your chip. f25 or even f35 is not unreaasonable.

4. Pick off, align and stack the best frames using AS!2 or a similar utility

5. Gently enhance in Registax to bring the detail out of the noise

6. Use something else (PS, Gimp, etc.) to deconvolve and blur/mask to reduce noise and enhance edge detail.

With a C11, you should most definitely be able to get something like this:

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#10 Kevdog

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Posted 16 December 2012 - 05:56 PM

I'm not too familiar with that particular camera, but the guidelines for applying it to planetary photography should be similar to those for the more popular Canon range:

1. Capture as many frames as you can in a short time - this essentially means using a video mode, if the camera has one. You need a LOT of frames to combat the noise inherent in DSLR short, low-light exposures. When I say a lot, I mean ideally a thousand or more.

2. If using a video mode, try to pick the one with the least compression and highest frame rate. For example, the Canon 60D has a mode where it will use only the middle 640 x 480 pixels, but will record at 60fps.


I shoot the video at 24fps for about a minute. So about 1300 frames or so. I also use the digital tele-converter to only take the middle part of the sensor.

3. Try to get a large image scale on your chip. f25 or even f35 is not unreaasonable.


So using a 2X barlow with my chip size equates to about a 10mm eyepiece. I would need a really good night to push up to a 5mm equivalent (a 3X barlow?). Would it still be worth trying a 3X barlow when the seeing is only so-so? Do you pick out the few good frames you might get?

4. Pick off, align and stack the best frames using AS!2 or a similar utility

5. Gently enhance in Registax to bring the detail out of the noise

6. Use something else (PS, Gimp, etc.) to deconvolve and blur/mask to reduce noise and enhance edge detail.

With a C11, you should most definitely be able to get something like this:


I'll have to read and learn more about these. So far I've only used Registax, and I only know the default settings for the most part.

Thanks for the detailed reply!

#11 GreatGigInTheSky

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Posted 16 December 2012 - 08:51 PM

Hi Kev,
RedLion is giving good advice. The movie mode with the highest frame rate you have is probably going to give the best results. The idea is to freeze the "seeing" so as to get the sharpest images possible. You also want as many frames as you can get in a short period of time (for Jupiter, less than about 3 minutes so the rotation of the planet doesn't blur the resulting stack). You can then stack and wavelet sharpen in Registax. AS!2 (Autostakkert 2) is probably the state of the art for stacking right now. You could stack there, then bring the .TIF or .PNG file into Registax for wavelets.

Your intuition is correct about the barlows -- it takes good seeing to use a 3X barlow, but when it works, it can be great.

If you get really interested in this, you may want to invest in a video camera that's more suited for the purpose.

Here's an example of a recent image from a C11 using a 3X barlow and a video camera, shot at 60fps. You have most of the gear you need to produce something like this -- it just takes time and experimentation. You might want to come hang out in the Solar System Imaging and Processing forum for a while -- there's a great wealth of knowledge and experienced folks willing to give advice.

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#12 kargan

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Posted 25 March 2013 - 03:47 PM

Great thread, I am going to try some of this. Here is what I have:

C11 HD, CGEM DX and a Cannon T2i (550D).

What I have tried so far:
Proper focus with a B-mask. Good polar alignment.
Use Backyard EOS, click 5x button in Backyard EOS, tried various exposure settings. Capture 1000 frames, stack in Autostakkert 2, Wavelets in Registax.

Results: Not so hot, definitely nothing approaching the above.

Questions:
1. The image looks like garbage in BYEOS when capturing, is that normal? I cant tell if focus is perfect, so I slew to a nearby star and use the B-mask there, lock the mirror and slew back but it always looks terrible.
2. Would a 2x barlow help or hurt? If seeing is the issue I expect it will make it worse.
3. What ISO/exposure settings work best? The attached photo was 200 ISO, 1/30th of a second.
4. Is clicking the 5x in BYEOS the same as clicking the Live View and then + button on the camera itself or do I actually need to hit those buttons on the camera?
5. Am I better off not using BYEOS and just using the Movie Crop Mode on the camera or am I basically getting the same thing?
6. Maybe it is collimation, I will have to really check that tonight.

I can get crisp Moon shots and DSOs, but Jupiter (and Saturn) are really throwing me for a loop!

Thanks for any help!!

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#13 DaemonGPF

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Posted 25 March 2013 - 04:29 PM

Think of it like this - ever look at a quarter thrown to the bottom of a swimming pool? Notice how it's constantly distorted by the ripples in the water, but every so often for a fleeting moment you get clarity where the coin looks sharper for an instant and then is gone again?

So when you look at this in your capture, or at an individual frame basis, it's really the same sort of thing which is why a high frame rate and as many frames as you can capture before planetary rotation becomes a factor is key. You'll capture maybe a few to several thousand frames and end up stacking only a handful which provide enough clarity to improve your overall image. Stack enough and you can then see the benefit of sharpening and wavelets more than you can with a single frame or small stack.

A fast frame rate camera designed for planetary imaging is extremely helpful to capture those brief moments.

Your approach by sharpening on a star is a good one. This is how I do it.

Try Autostakkert out. It simplifies the approach. Then shows you the difference between different sized stacks.

#14 GreatGigInTheSky

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Posted 26 March 2013 - 03:26 PM

Kargan,
1. yes, the image in the live feed is going to be noisy and show the effects of the momentary changes in seeing. Your focusing method is reasonable and should work. I've found that with practice, I'm able to focus by looking at the planetary image.
2. You're correct -- more magnification will only make things worse with poor seeing, but generally more image scale is helpful. Most of the time I image with a 3x barlow, unless seeing is really bad, when I use a 2x. However, which barlow is right for you is directly dependent on the size of the pixels on your sensor.
3. I can't say too much about your particular camera settings, as I haven't used that cam for planetary imaging. What I can say is that the highest frame rate you have available that is consistent with reasonably bright images is what you'll want to use, as it "freezes" the atmospheric seeing better than a lower frame rate.

The rest is camera specific, and I can't help there. Maybe someone using this cam for planetary imaging (although I don't expect there are many) might weigh in here. Good collimation is definitely required.

Josh, Kargan wrote that he is using AS!2.






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