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NINA ROI; how to handle Darks/Biases

Stefan Berg Nighttime Imaging 'N' Astronomy (N.I.N.A. / NINA) Acquisition Calibration
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John Stone avatar
John Stone avatar
Hi,

I'd like to use the ROI feature in the Target Scheduler to cut down on the size of the subframes when I'm not going wide with my full-frame camera.

But how do you handle getting matching Darks/Biases during stacking in WBPP?

Does NINA write some kind of meta-data to the FITS header that WBPP can read to "cut-out" the correct portions of the full-frame master Dark/Bias?

Or, do you have to build a dark library for ever ROI you use?

Anyone using the ROI, I'd like to hear from you.

Thanks.
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Frédéric Ruciak avatar
Frédéric Ruciak avatar
Hi John, I am a little bit primitive but I would just build a dark and bias as well as flat library with the ROI of your choice, and you are sure that they will all it. If there is a clever way fantastic, but I do not know about.
CS Frédéric
andrea tasselli avatar
andrea tasselli avatar
You have to create the matching Master Dark/Flat/Bias in NINA to feed to PI afaik.
Steven Miller avatar
Steven Miller avatar
I’ve used the ROI feature and there are two ways to handle it:


1)  Usually I just shoot calibration frames with the same ROI setting.


2) The second way is I’ve cropped all of my captured frames post capture to speed stacking and reduce storage, both the lights and calibration frames before processing.   As long as I used an even crop factor so that I didn’t disrupt the RGB Bayer pattern, that all worked also.  Now, in this case, I did it to all of them, the lights and the calibration frames the same way but I expect that if you shoot an ROI with lights, you could probably crop old calibration frames and if you crop them the same way as the ROI of the lights were captured, you would be fine.

Now, although I do own PI, I usually do my stacking in either SIRIL or Astro pixel processor so there may be a hiccup specific to PI in any of these steps I’ve taken.  But I expect it’ll work as long as the dimensions are the same, and the offset in the cropping is the same..
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Jeff Rothstein avatar
Jeff Rothstein avatar
I use Steve’s technique #1 because I’m a little OCD annout stuff like this and a friend uses #2.  Both work well.