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Optolong L eNhance processing advice?


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This is my first attempt at processing an image taken with an Optolong L eNhance filter and I'd appreciate some advice on how the image can be improved. I think that the colour balance may be a bit off, but I'm not sure if this is to be expected with a dual narrow band filter?

My imaging setup is a C8 SCT with a 0.63 reducer and an unmodified Canon 70D. 

The image was stacked from 35 x 300s frames at ISO 1600, plus darks, flats and bias frames. Post processing was done in Photoshop.

Any advice will be greatly appreciated as I'm a newbie at post processing and mainly rely of action scripts and basic level adjustments.

NGC 7380 - Wizard Nebula3.jpg

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A really good start I would say, just make sure that the histrogram isn't touching the left hand side, as this means infomation is lost and only displays black.

Also, I would make sure that the spacing on the reducer is correct as there is a small amount of curvature around the edges (you can tell from the star shapes).

Apart from that it is a good image in my opinion. Good colours in the neubla and not overdone. I would look to try some curves streches to bring out some of the fainter background as long as you dont bring too much noise into the picture.

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Thanks CloudMagnet for the response.

I had some concerns when I was setting up the subs as the histogram in APT didn't look good. I was worried about either pushing up the ISO or exposure time. so I left it run and tried to stretch it as much much as possible in post processing.

I can see what you mean about a possible reducer error, I've just switched to an inexpensive setup to allow me to screw the filter into the camera nose piece., I'll check the measurements 

 

Capture.PNG

Capture2.PNG

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Yep, looking at the streched version, I dont think there is too much more to get out of that. It might be worth adding a little of of sharpen to the image to give a bit more definition to the nebula. Still fantastic though.

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Thanks again, I fished out a couple of dodgy subs, had another go processing, did a little sharpening and ended up with this image, which I'm quietly chuffed with as a first foray into filters. I can't help but see the curvature around the edges but I'll chalk that up to experience and check the flatener / reducer.

 

NGC 7380 - Wizard Nebula5.jpg

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In my eyes, the re-process has too much noise reduction.

I prefer your original. It looks a lot more natural, although the black point is still pretty clipped.

The trick is to leave just a little noise in (not that I'm much good at it myself) :)

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Hi

To help with the noise, probably best to lose the dark frames, dither between exposures and stack with a clipping algorithm. You could then avoid the dark background.

But hey, the c8 is the single most difficult telescope from which I have ever tried to obtain a decent image. Amazing effort:)

I find processing colour tricky but the good news is that since the HST started doing its filter thing, anything goes. So take your pick!

HTH

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So far I've stuck with the default settings in Deep Sky Stacker, apart from choosing Sigma Clipping for the lights. I'm thinking that my subs are under exposed but as it's going to be cloudy where I am for the next few nights I'll experiment with the vast array of stacking and processing options to see how they affect the final image.

I'm planning on trying to capture the Bubble Nebula next but I'll need to look into improving the exposure histogram, I'm wondering if it's asking too much of an unmodified DSLR?

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