Would it be possible to add to the Astronomy LiveView screen a feature where multiple LiveView frames would be averaged together. The amount of averaging would be adjustable (1 to 50). There are times when I try to use the Astronomy LiveView screen to re-position a galaxy to compose the picture. These galaxies are very dim so I use the highest possible ISO of my Nikon D5300 camera. This is very noisy but most times I can see a very faint star amongst the noise. I believe that by averaging successive LiveView images you can dramatically reduce the noise and make it easier to detect faint objects.
Peter
P.S. a simple 1st order low pass filter would do the job
LVavg(n) = [LV(n) + K*LVavg(n-1)]/[K+1] where
LVavg(n) = Filtered LiveView image to be displayed
LV(n) = LiveView image normally displayed now
LVavg(n-1) = Filtered LiveView image from the previous scan
K = averaging factor {0 to 50}
Astronomy Module LV suggestion
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Duka Istvan
- Posts: 684
- Joined: Sat Oct 03, 2015 7:57 pm
Re: Astronomy Module LV suggestion
I will add this feature in the next beta release.
If i understand right this formula should applied for every color component of pixels from live view ?
If i understand right this formula should applied for every color component of pixels from live view ?
Re: Astronomy Module LV suggestion
Duka,
You are right. You would filter the R, G and B data separately.
In most photo editing programs the filtering they offer are luminance noise and color noise. You might want to look at making the result be a greyscale image. You may remember when we discussed the Starsize calculation that I had you add the R, B and G values together to create a greyscale equivalent. You could try creating this greyscale equivalent for the LV image and then filtering it and display it as a greyscale image. This might result in an even better filtered image because the color noise should be reduced. This should also be less calculations. The camera's LV display for astronomy is primarily used for focusing and for composing the photo. Using greyscale images for this purpose is acceptable.
Peter
You are right. You would filter the R, G and B data separately.
In most photo editing programs the filtering they offer are luminance noise and color noise. You might want to look at making the result be a greyscale image. You may remember when we discussed the Starsize calculation that I had you add the R, B and G values together to create a greyscale equivalent. You could try creating this greyscale equivalent for the LV image and then filtering it and display it as a greyscale image. This might result in an even better filtered image because the color noise should be reduced. This should also be less calculations. The camera's LV display for astronomy is primarily used for focusing and for composing the photo. Using greyscale images for this purpose is acceptable.
Peter
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Duka Istvan
- Posts: 684
- Joined: Sat Oct 03, 2015 7:57 pm
Re: Astronomy Module LV suggestion
Please check this version https://s3.amazonaws.com/download.digic ... 0.58.0.exe the speed isn't optimized yet
Re: Astronomy Module LV suggestion
Duka,
I tried out your version. Your code executed perfectly. I found that the filtering slider you provided was very sensitive. Probably it could have been scaled for 0 to 5 instead of 0 to 50. I could immediately see the noise disappear when using just a little bit of filtering.
Last night the objects I was imaging all has bright stars close by so there was no advantage using the filtering. When using the filtering the star stood out quite well but whenever I repositioned the telescope the filtering would smear the image until the telescope stopped moving. I expected that to happen...low amounts of filtering [0-5] and fast updates would minimize that affect. The filtering looks like it also affects the starsize calculation...that may just be the speed optimization you mentioned. I think I like the idea of the image filtering affecting the starsize calculation...smooths out the fluctuations of the starsize number which makes it easier to see smaller focus adjustments.
Overall, I think it is a feature that I will use and other astrophotographers may also like. It's not a "game changer" but it is useful.
Peter
I tried out your version. Your code executed perfectly. I found that the filtering slider you provided was very sensitive. Probably it could have been scaled for 0 to 5 instead of 0 to 50. I could immediately see the noise disappear when using just a little bit of filtering.
Last night the objects I was imaging all has bright stars close by so there was no advantage using the filtering. When using the filtering the star stood out quite well but whenever I repositioned the telescope the filtering would smear the image until the telescope stopped moving. I expected that to happen...low amounts of filtering [0-5] and fast updates would minimize that affect. The filtering looks like it also affects the starsize calculation...that may just be the speed optimization you mentioned. I think I like the idea of the image filtering affecting the starsize calculation...smooths out the fluctuations of the starsize number which makes it easier to see smaller focus adjustments.
Overall, I think it is a feature that I will use and other astrophotographers may also like. It's not a "game changer" but it is useful.
Peter