Author Topic: Noob with a question about dark frame batch processing please  (Read 2008 times)

Offline Jetstream Rider

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Hello PixInsight people, nice to be here.

PixInsight has been recommended to me by an astrophotographer friend, and so I've had a bit of a look around and can't find an answer to a question I have.  I am not yet a proper astrophotogrpaher, but I am an experienced light photographer and time lapse shooter.  I have shot some lovely aurora time lapse from an aeroplane - and by necessity the ISO had to be very high to keep the shutter speed as short as possible - I don't have the luxury of being able to track.  Because of this, the images are noisy - so to help reduce that I'd like to use dark frames to get rid of some of the noise (I know I can't lose it all and I have dark frames taken at the time for the same shutter speed and ISO etc).

What I am after therefore is a bit of software that will batch process a few thousand images and apply a master dark frame to each one - and output each file as a separate one that I can then animate into the time lapse.  I know that PixInsight can stack dark frames and combine them to give one lovely final image - but can it batch process thousands automatically and apply a dark frame to each one?  If so, how do I do it?

I can't find any other software that will do this yet without a massively time consuming and quite manual process.  If PixInsight can't do it - does anyone know a bit of software that does?

I know I am working at a crossover of astro and light photography where most light photographers do not know or understand dark frames, so its a niche thing, but would be really useful if I could do it.

Many thanks indeed.
JR

Offline pfile

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Re: Noob with a question about dark frame batch processing please
« Reply #1 on: 2018 November 16 18:55:44 »
while you may or may not be able to do all 1000 in one go, you should be able to do some significant portion of them at once, subject to memory availability on your machine.

both the ImageCalibration process and Debayer process can take a list of images as input, and a directory to output images to. so what you want to do is already built into pixinsight.

rob

Offline Jetstream Rider

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Re: Noob with a question about dark frame batch processing please
« Reply #2 on: 2018 November 17 03:10:36 »
Fantastic. Thank you.  I'll get a trial copy and give it a go.  Even if I can do it in two or three goes it saves a huge amount of boring and time consuming processing. Great news.

Offline Andres.Pozo

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Re: Noob with a question about dark frame batch processing please
« Reply #3 on: 2018 November 17 04:15:57 »
If you had memory problems trying to integrate hundreds of DSLR RAW frames, the easiest solution is to convert them to XISF before. There is a batch conversion tool.

Offline pfile

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Re: Noob with a question about dark frame batch processing please
« Reply #4 on: 2018 November 17 08:34:58 »
that's true - CR2/NEF files can not be read 'incrementally' and XISF can, so the memory pressure while using XISF files is much lower.

there are a lot of ins and outs here, you have to make sure your CR2/NEF files are not debayered in the conversion to XISF to support correct calibration. the DSLR_RAW module needs to be set to 'pure raw'.

rob

Offline Jetstream Rider

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Re: Noob with a question about dark frame batch processing please
« Reply #5 on: 2018 November 17 09:42:23 »
Ok, I'll check that out, thanks. Does PixInsight not do it image by image, and so only have the image being processed and the dark frame in memory at any one time?

Offline pfile

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Re: Noob with a question about dark frame batch processing please
« Reply #6 on: 2018 November 17 11:51:04 »
there's a great deal of parallelism involved to speed things up, so lots of stuff is loaded into memory at any one time.

rob

Offline Jetstream Rider

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Re: Noob with a question about dark frame batch processing please
« Reply #7 on: 2018 November 17 12:42:03 »
Ok thanks - I think the only thing I can do is try it and see what happens.  Does the trial period use the full power of the software or is it restricted until you get a full licence?

Offline pfile

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Re: Noob with a question about dark frame batch processing please
« Reply #8 on: 2018 November 17 12:45:03 »
the trial is fully functional so what it does is what it will do when you buy it  :)

rob

Offline Jetstream Rider

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Re: Noob with a question about dark frame batch processing please
« Reply #9 on: 2018 November 17 12:54:21 »
Ace, I'll give it a go.  I think I'll do some tutorials first though, so I know what to expect. Thanks everyone for your help.

Offline pfile

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Re: Noob with a question about dark frame batch processing please
« Reply #10 on: 2018 November 17 13:33:41 »
that's a good idea, although the trial period is very long there is a lot to learn and it would be good to hit the ground running.

rob