Author Topic: Master Dark issues - vertical lines  (Read 2704 times)

Offline jcinpv

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Master Dark issues - vertical lines
« on: 2017 July 02 13:31:12 »
I’m a bit concerned about the PI master Dark files and BPP in general.

An individual Dark file looks like the first image (Dark-1)  (all images with STF unlinked applied, all preprocessing with BPP).

The Master Dark file looks like the second image (MasterDark-2).

And applied to the Lights it does this (Light-DBE-3).

And then I have to go through hoops to get rid of the vertical streaks.

It also doesn't look like the vignetting is getting handled with the Flats.

Any suggestions?
John C.
Paulden, AZ

Offline vicent_peris

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Re: Master Dark issues - vertical lines
« Reply #1 on: 2017 July 02 14:50:33 »
Hi,

Could you please upload the set of the individual bias and dark frames?

Best regards,
Vicent.

Offline jcinpv

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Re: Master Dark issues - vertical lines
« Reply #2 on: 2017 July 02 21:26:11 »
To upload the full set of Darks and Bias frames will be a lot of data. The 20 Darks are 19.5MB each (390 MB total). The 70 Bias are 19.3 MB each (1.35 GB total).
You might be able to get by with only 10 frames each.
Where would I upload them to?
I can put all of them in my Dropbox.
Why would you not want any of the Flats?

John Carter
John C.
Paulden, AZ

Offline jcinpv

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Re: Master Dark issues - vertical lines
« Reply #3 on: 2017 July 02 23:28:06 »
I have put 20 Dark frames and 20 Bias frames in the following Dropbox folder:
https://www.dropbox.com/sh/90qdhbgr2z27u9j/AAC2J9V1uyYfjQtuO-aFal7Ka?dl=0
It contains two subfolders, one for DarkFrames and one for BiasFrames.
It may take a few hours to get them all uploaded.

jc
John C.
Paulden, AZ

Offline jcinpv

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Re: Master Dark issues - vertical lines
« Reply #4 on: 2017 July 03 10:42:36 »
Using a standard deviation to combine the dark frames (using Deep Sky Stacker - without processing with Bias) results in a much smoother image, but I think it also removed a few of the hot pixels.
Combining them as Minimum with DSS results in a usable image with all hot pixels intact.
I'm going to experiment with each of the six masters (FITs) created by DSS for each of the Flats, Bias and Darks.

jrc
John C.
Paulden, AZ