Andromeda Equipment Setup and Image Processing

[Kevin_A]

I'm very new to astrophotography and still have a lot to learn. Last night I took a lot of pictures using different aperture and exposure settings. This is one of the better pics. I ran the RAW file thru LRC. I ran denoise because without doing that any settings I changed in LRC made it look really awful. Even after running denoise any changes just made a mess so this is just the denoised pic. I know that I need to stack to get a good image but I would think this pic should look a lot better based on what I see when I look directly thru the scope. Any suggestions on equipment or LRC changes that would improve the image?

Here are the details

Celestron 8SE

Sony A7R IV

F / 6.3 focal reducer

T-Adaptor with 2x Barlow

ISO 2000

4 second exposure



View attachment 126aca2109764daf958fb66aae11466a.jpg



Thanks!

 

[nighthiker]

1) The image is out-of-focus, so useless.

2) 4 sec is a VERY short exposure time for astro and f/10 isn't that fast. Is the guiding so poor? I usually take 20-60 sec, but that depends on many factors.

3) I'm not an expert in DS, but I don't understand why you use a Barlow and a focal reducer.

4) There are enough 'How-to' manuals and videos for the first steps. Go ahead with that and come back once you have a specific question.

5) I found this review of your scope (https://astrobackyard.com/celestron-nexstar-8se/) and it explains some issues:

- With a focal length of 2000mm it's rather for planetary work

- It's rather for visual than for photographic work

- The mount is a little bit weak, so I'm not sure about your heavy camera on that not-so-stable mount.

6) I'm using a good 300mm lens and a very good tracker to capture Andromeda and I can see the main features of that galaxy already on single frames.

 

[DavidWright2010]

I'm very new to astrophotography and still have a lot to learn. Last night I took a lot of pictures using different aperture and exposure settings. This is one of the better pics. I ran the RAW file thru LRC. I ran denoise because without doing that any settings I changed in LRC made it look really awful. Even after running denoise any changes just made a mess so this is just the denoised pic. I know that I need to stack to get a good image but I would think this pic should look a lot better based on what I see when I look directly thru the scope. Any suggestions on equipment or LRC changes that would improve the image?

Here are the details

Celestron 8SE

Sony A7R IV

F / 6.3 focal reducer

T-Adaptor with 2x Barlow

ISO 2000

4 second exposure

View attachment 126aca2109764daf958fb66aae11466a.jpg

Thanks!

As Nighthiker said, you need to review your whole approach. The Celestron 8" is way too much magnification for Andromeda. Even with the focal reducer - and all that magnification stresses your tracking and guiding.

Maybe you can put your camera and a long lens (200 or 300mm) piggyback on the C-8?

This is a single exposure at 200 mm f/4, 30 seconds with an aps-c sensor camera:



With a full-frame sensor, you could probably go to 400 mm.

Stacking 180 of such images (and flat field images) get you:



David

 

[nighthiker]

I'm very new to astrophotography and still have a lot to learn. Last night I took a lot of pictures using different aperture and exposure settings. This is one of the better pics. I ran the RAW file thru LRC. I ran denoise because without doing that any settings I changed in LRC made it look really awful. Even after running denoise any changes just made a mess so this is just the denoised pic. I know that I need to stack to get a good image but I would think this pic should look a lot better based on what I see when I look directly thru the scope. Any suggestions on equipment or LRC changes that would improve the image?

Here are the details

Celestron 8SE

Sony A7R IV

F / 6.3 focal reducer

T-Adaptor with 2x Barlow

ISO 2000

4 second exposure

View attachment 126aca2109764daf958fb66aae11466a.jpg

Thanks!

As Nighthiker said, you need to review your whole approach. The Celestron 8" is way too much magnification for Andromeda. Even with the focal reducer - and all that magnification stresses your tracking and guiding.

Maybe you can put your camera and a long lens (200 or 300mm) piggyback on the C-8?

This is a single exposure at 200 mm f/4, 30 seconds with an aps-c sensor camera:



With a full-frame sensor, you could probably go to 400 mm.

Stacking 180 of such images (and flat field images) get you:



David

I agree!

The review doesn't recommend piggyback due to the not-so-stable mount. So yes, read the review and additional information and think about what you want to do: Visual or photographic, planetary, solar or nebular observations. Sorry, but 'astro' is very wide field and can get quickly expensive and time-consuming (and you might even get addicted to it ). It's always a good advice to start with little investment and just use what you have to check it out. You will quickly find out what you like and if you need additional equipment. My usual tip: Only buy new equipment if you can explain WHY you need it.

Now that you already have some equipment: Read how other people have used the 8SE with a camera. 'celestron 8SE dslr' gives me already plenty results! Happy reading!

 

[Kevin_A]

Thank you. I really appreciate the feedback. Still have a ton to learn.

 

[nighthiker]

Thank you. I really appreciate the feedback. Still have a ton to learn.

I appreciate that you are willing to learn (as there are many users who just want to get a perfect summary, if possible in one sentence)! You are on the right way!

 

[swimswithtrout]

Why are you using a reducer and Barlow ????? By my calculations, you are shooting at 2,550mm/ f12. Andromeda is so large, you have to have it perfectly framed to fit on the corner to corner diagonal, using a full frame camera and 600mm lens, for it to even fit in your field of view. F12 is much too slow to capture anything with 4 sec. exposures. The SE mount is an alt/az mount and intended for very casual visual use only. The 8" severely overloads the flimsy plastic one arm design and for any kind of astrophotography beyond lunar/ planetary imaging, you need a good equatorial mount, not an alt/az. Without equatorial tracking and the ability to take accurately guided 60" +++ images, f10 is too too slow .

Andromeda is not an outlier in size. Many / most nebula are too large to fit in the field of view of a 2000mm system. Most nebula are best framed at 400-800mm.

SCT's excel at lunar/planetary imaging, but even then, that is done via high speed video capture using dedicated planetary cameras capable of true 1:1 pixel uncompressed video at up to 200fps. If deep space objects are what you are wanting to capture, you have the completely wrong system. You don't even need a telescope for many targets. What is mandatory, is a good tracking mount.