Author Topic: Flat Issue - Question  (Read 2668 times)

Offline Farzad_k

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Flat Issue - Question
« on: 2017 February 16 16:29:12 »
Hello,

I am still working on my first image and I seem to have a few problems that I am not able to resolve or understand.

I am using Flats that I acquired by shooting at a bright and flat Surface Pro 4 screen. I can calibrate them just fine and I notice that when I open the calibrated files they look absolutely black while when I open the original RAW (Nikon NEF) files they kind of look gray-ish. When I integrate these Flats I get the strange all white on the low rejection. When I use this integrated flat to do the lights PI stops at the end and says it found no stars because apparently this integrated flat is making the integrated lights all solid black.

Since when I integrate lights without the Flats I do get a decent image I am assuming the issue is with the Flats. I am attaching a file that shows the Flat as seen by Photoshop and you can see its histogram, and I am attaching the integration result scree of the Flats I have used.

And also - my final master comes out as black and white when I take it in for image processing. I wonder if that also is normal because I have Sequence Generator Pro do the shooting with a Nikon D750.

I am not able to make the attachments since the limit of size is exceeded. I have posted my files here on DropBox and I hope this is not against the rules.

https://www.dropbox.com/sh/px0zk0arojcp360/AAC6THYKAnPmFKMRLRPa-b-ba?dl=0


Thanks

Farzad








« Last Edit: 2017 February 16 17:38:02 by Farzad_k »

Offline Farzad_k

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Re: Flat Issue - Question
« Reply #1 on: 2017 February 16 16:35:51 »
Here I am attaching the resulting MasterLight without using the Flats, and the image that comes out as black and white.


Offline Alejandro Tombolini

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Re: Flat Issue - Question
« Reply #2 on: 2017 February 16 16:41:43 »
Hi Farzad, Are you using BBP script? If so, remember to check CFA option.
Saludos, Alejandro

Offline Farzad_k

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Re: Flat Issue - Question
« Reply #3 on: 2017 February 16 16:50:34 »
No, I am actually doing the work step-by-step. But I am trying that now. Thanks.

Offline Farzad_k

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Re: Flat Issue - Question
« Reply #4 on: 2017 February 16 16:59:38 »
And the BPP also returns an error regarding integration of the Flat Frames. See attached please. I don't know why PI does not like my Flat frames.


Offline Farzad_k

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Re: Flat Issue - Question
« Reply #5 on: 2017 February 16 19:25:01 »
In figuring out if it is me or the data that I have collected I picked up a set of data from the professionals and processed them and...it is not me, so it has to be my Flats.

Is it possible that PI does not like NEF RAW files as Flats?

Offline pfile

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Re: Flat Issue - Question
« Reply #6 on: 2017 February 16 20:51:18 »
just guessing that the calibration of the flats has gone wrong, leaving no signal in the flats. you should open the calibrated flats and see if they still look like flats.

rob