Can you tell the difference?

[crimbfighter]

I am playing with more options for processing images because I am playing around more with my telescope. I have been playing with using a program called Autostakkert, which processes individual frames from a video file. It is useful because it can compensate for some atmospheric distortion by stacking frames. I played with it a bit using my D500 and Nikon 200-500 with the moon tonight to see if there was a noticeable difference between editing a stacked image vs. a single exposure. I'm curious to see which, if either, is preferred. The first is using a single image and the second is using a stacked image from video frames. Can anyone tell a difference or have a preference?

1.

2.

 

[zombiesniper]

They look identical to me. Including the two red pixels on the upper left side of the moon in the black.
Are you sure these are different images?
If so, I can't tell a difference.

 

[crimbfighter]

They look identical to me. Including the two red pixels on the upper left side of the moon in the black.
Are you sure these are different images?
If so, I can't tell a difference.

Haha, I'll have to double check... I may have accidentally selected the same image twice...

 

[crimbfighter]

They look identical to me. Including the two red pixels on the upper left side of the moon in the black.
Are you sure these are different images?
If so, I can't tell a difference.

Fixed.. I accidentally selected the same attachment twice.

 

[zombiesniper]

There seems to be a bit more noise in the first image.
Second appears to have same quality with less noise.

Interesting.

 

[crimbfighter]

There seems to be a bit more noise in the first image.
Second appears to have same quality with less noise.

Interesting.

That's actually the same thing I noticed, too. I dont thing the stacked image resolved more detail, but it seemed to do it with less noise and maybe a tad more dynamic range, especially in the mid tones. Stacking is a common technique used in astrophotography, and the stacking process reduces noise quite a bit.

 

[zombiesniper]

I normally stack in photoshop.
I'd love to see the difference between Autostakkert and Photoshop but it's a Windows only software.

 

[Designer]

I see higher contrast and definition in the stacked version.

 

[otherprof]

I am playing with more options for processing images because I am playing around more with my telescope. I have been playing with using a program called Autostakkert, which processes individual frames from a video file. It is useful because it can compensate for some atmospheric distortion by stacking frames. I played with it a bit using my D500 and Nikon 200-500 with the moon tonight to see if there was a noticeable difference between editing a stacked image vs. a single exposure. I'm curious to see which, if either, is preferred. The first is using a single image and the second is using a stacked image from video frames. Can anyone tell a difference or have a preference?

1.
View attachment 170193

2.
View attachment 170194

I agree with Designer. The second one appears to have higher contrast. But why not try this again without letting us know which image is stacked until the comments about differences are in?

 

[Derrel]

The differences seem rather slight to me...neither is markedly different than the other...but,now,on Visit #3, the first appears "crisper"...

 

[adamhiram]

The differences seem rather slight to me...neither is markedly different than the other...but,now,on Visit #3, the first appears "crisper"...

Agreed. I see more noise in the first image, but it also looks sharper. The 2nd image looks like too much noise reduction was applied at the cost of some detail. Have you tried the stacking method using still frames instead of video frames?

 

[DaPOPO]

The second is a little lighter and crisper.

 

[crimbfighter]

I normally stack in photoshop.
I'd love to see the difference between Autostakkert and Photoshop but it's a Windows only software.

To what end do you stack in Photoshop? Do you stack for DOF purposes or something similar to what I am trying?

 

[crimbfighter]

I see higher contrast and definition in the stacked version.

I definitely agree on it having better contrast, and perhaps as a result it appears there's more definition.

I am playing with more options for processing images because I am playing around more with my telescope. I have been playing with using a program called Autostakkert, which processes individual frames from a video file. It is useful because it can compensate for some atmospheric distortion by stacking frames. I played with it a bit using my D500 and Nikon 200-500 with the moon tonight to see if there was a noticeable difference between editing a stacked image vs. a single exposure. I'm curious to see which, if either, is preferred. The first is using a single image and the second is using a stacked image from video frames. Can anyone tell a difference or have a preference?

1.
View attachment 170193

2.
View attachment 170194

I agree with Designer. The second one appears to have higher contrast. But why not try this again without letting us know which image is stacked until the comments about differences are in?

I thought about making it unknown which was stacked and which wasn't, and perhaps that would have been a good thing to try. I figured that with this, it wasn't as much of a "which do you like best" scenario and relied more on "can you spot the differences." Being less about like and more about noticeable difference I didn't think keeping it a secret would make for a better outcome. But, I've been wrong before!

 

[crimbfighter]

The differences seem rather slight to me...neither is markedly different than the other...but,now,on Visit #3, the first appears "crisper"...

Thanks Derrel. I think the take away for me is that there is a difference, though maybe not so much so that it is notably out performing a single exposure. Though it does help with noise and I think added contrast. I think stacking like this may be more beneficial when going after smaller targets or at a much higher magnification where atmospheric distortion effects the image much more than this test of the moon.

The differences seem rather slight to me...neither is markedly different than the other...but,now,on Visit #3, the first appears "crisper"...

Agreed. I see more noise in the first image, but it also looks sharper. The 2nd image looks like too much noise reduction was applied at the cost of some detail. Have you tried the stacking method using still frames instead of video frames?

I have not tried using stills instead of video, though I believe the program can do it. I think it is less an issue of stills vs. video because the video frames produce good individual frames. I think the issue is more in which frames from the video are stacked. The program analyzes and ranks each frame, places them on a graph and the user selects the percentage of frames to use, starting with the best and going to the worst. For this I selected the best 75% of the frames, but I probably need to lower that to the best 50%. Basically about half the frames were all ranked very good and from 50-75% they were OK, and I think that extra 25% of OK frames included some frames with smearing in the details from atmospheric distortion. I think using a smaller number of frames with only very good detail will improve the overall detail of the stacked image and still have the benefits of better noise reduction and better contrast.

The second is a little lighter and crisper.

Thanks for the reply!