comparing processing techniques

[darbyvet (Carl Darby)]

So while i wait for the rain to stop I figured i would play around with some of the processing techniques i have used to see which gives the best results.Here is the fruit of my labor.

The first pic shows the separate rgb channels and the result of combining them in Astraimage

The second pic shows the same images that were processed in 4 different ways.

Astra 1:
The avis were processed with Reg6
The RGB channels were combined in Astraimage
Brightness,contrast and gamma were adjusted in Astraimage
LR deconvolution was performed on the color image (psf 0.7, 5 iterations).
Unsharp filter was applied to the image (radius 1 sharpness 1)
Convolution filter was applied -Mild blur

Astra2:
The AVIs were processed with reg6
EACH channel (R,G and B) had LR convolution,unsharp mask and blur applied.The amount of convolution was adjusted to get the most detail without too much noise.
The three channels were then combined in Astraimage
The final color image had brightness, contrast and color adjusted

Pshop
The avis were processed with reg6
The RGB channels were combined in Astraimage
The image was imported in photoshp elements 8
Auto color,contrast and sharpness were applied
An unsharp mask was applied
Mild blur was applied
A duplicate layer was made and a high pass filter applied and the layers were combined (soft light 100% opacity for the filter layer)

Reg6
The avis were processed with reg6 (wavelets)
The 3 channels were combined in Astraimage
The color image was then re-imported in reg6
Color balance,brightness,contrast were adjusted
A denoising filter set to 1000 was applied to the image

I came to some conclusions after doing this (apart from that I must be crazy!). I would like to hear what you guys think before I comment

[Poita (Peter)]

Okay, I'll bite.

I like the colour in the photoshop image, but a lot of detail appears to be blown out, more careful adjustment of the curves might be able to recover that data, I wouldn't mind having a go at the source files at some point. I also prefer the Astra1 image to the Astra2 image.
Ideally for me, it would be a blend of nearly all those images and be slightly less sharpened.

I'm interested in that the blue channel has by far the least detail and most blur, but there is quite a bit of blue in the final images.

Like most astro- images I see, these have a slightly over-processed, over-sharpened look, but that is probably just personal taste, I find a lot of Bluray releases to be over sharpened as well

Having said all of that, if I managed to get *any* images that good I'd be stoked.

[darbyvet (Carl Darby)]

Thanks Peter,
I agree about the photoshop image.I dont really know how to use photoshop so I just used the guided editor mode with automatic sharpness,color correction etc.. I am sure that someone that knows how to use photoshop can do better.I will gladly post the Avis and/or RGB channel images if you want to play with them.

I thought it was interesting that it did not make much difference if I did the LR convolution before or after combining the RGB images. I thought that adjusting the RGB images separately would be better since I could apply more deconvolution to the poorer channels (ie blue) to sharpen them, but it did not make much difference to the final image

I agree that they are overprocessed, but i do like to see more detail.

I always have a poorer blue capture.I think it is a combination of being at quite a high lattitude (42 degrees), Jupiter is not that high in the sky so I am looking through more atmosphere, and the fact that the blue light waves are affected more by the atmosphere.

I am also manually focussing and the blue filter is not parfocal the the red and green so I have to refocus the blue channel before capture and it is hard to get great focus because the image is not so great to begin with. Hopefully when I get an electric focuser that will help.

If you look at the experts captures (Damian Peach) you will see that the blue capture is never as good as the r or g (although his are still fabulous!!).

I can probably post the R,G and B images online for you to play with.If you want the AVis I can post those on a free online storage site.let me know

[Poita (Peter)]

I'd love the files to play with, that way I can learn more about processing whilst I save up for the EQ6 mount.

Blue light is always somewhat defocused due to its wavelength I think? (I know that when setting up CRT projectors, the blue tube is always purposely defocused to get the white balance and brightness etc. right).

I have dropbox, or can give you ftp access to my site if you want to upload them that way, or can pull them down from wherever you put them.

Thanks heaps.

-Peter

[darbyvet (Carl Darby)]

Hi Peter,
here is the link to the BMPs for the image posted.They are stacked in reg6 already.The prewavelet bmps have just been stacked with no wavelet and the postwavelet have been processed obviously.
I dont think photobucket will let me upload the avids as they are 400mb each.If you have somewhere for me to upload them to let me know

http://s1118.photobucket.com/albums/k604/darbyvet/