Author Topic: M74, 36 minutes, 17" Planewave reflector  (Read 801 times)

Offline dougggg

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M74, 36 minutes, 17" Planewave reflector
« on: 2016 November 25 17:38:35 »
Looking for constructive criticism on the attached image. I've also attached the PixInsight process history file. Too much contrast? Not enough noise reduction? Something doesn't look right.

Did the normal pre-processing with devolution prior to the stretch. No pre-stretch noise reduction.

Doug

Offline oldwexi

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Re: M74, 36 minutes, 17" Planewave reflector
« Reply #1 on: 2016 November 26 13:16:16 »
Hi Doug!
The best pre-stretch noise reduction is:
Much more exposures with the same exposure time as this one.
I assume you took 6x6  minutes, or 12x3 minutes. This is by far not enough.
Take in minimum 30 exposures with 6 minutes.
This will get you a much more smooth background which allows stretching with less
artefacts in the background.

The image itself is already very deep, but needs more exposures as mentioned before.

Gerald.

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