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Orion - First multi-session project // Need your opinion please
Hello from Austria!
I am currently working on a complex project and need your opinion. I photographed the constellation Orion during three nights.
Equipment: Canon 6Da + Sigma 105mm A + Optolong L-Pro
Lights: 75sec. /f2.5 / ISO 800
I stacked the three sessions with the standard parameters (+ MBB 5% + LNC degree 1 (1iteration)).
I dithered the pictures. Does something have to be checked in APP if the images are dithered?
I have uploaded the result to you in various stages!
Can anything be improved here or is the result ok? Are the used settings ok for a "three session project" like this?
No, dithering is just about moving the telescope tiny fractions between each frame. APP will align those of course and this is where dithering helps as it makes bad pixels and fixed noise patterns move around so APP can filter those more easily. Other effects an also be dealt with like this, so I always tend to dither with pretty big steps, like 5-10 pixels. No extra setting is required for this and your result looks really good I'd say.
Thx for the info Vincent!
I dithered every third image for 10 pixels.
Is LNC degree 1 (1it) ok for a three session project or is this depending on the gradients in the subs?
That's a good dither schedule yes, if you have enough images. For small datasets (like 15 images) I would do it every frame.
The LNC is dependent on the overall background illumination per image, trying to get those more equal. This won't remove gradients though. And if it's fine with 1 iteration, then that's good. You can always end up with light pollution gradients, that's something you have to deal with using the light pollution tool.