PI 1.5 Rocks

[Jack Harvey]

Am starting to process some new Narrowband data and with the exception of  dark and flat field calibration am doing the entire image in PixInsight.  Registartion, hot/cold pixel removal, Image Integration and final processing with Histo, DBE, HDR, etc. Hopefully will have a finished example in a couple of days.  This is pretty exciting!

[Nocturnal]

Hi Jack,

How are you doing hot/cold pixel removal?

[Jack Harvey]

There is that option in Image Integration -pixel rejection

[Nocturnal]

Ah, thanks. I thought it was a separate step. I'll have to compare how it works next to my own hot pixel reject code that's based on dark frame analysis.

[Jack Harvey]

Please give me your thoughts as to which algorithm and settings work best.

[Jack Harvey]

BTW enable the generation of the pixel reject maps and you can readily see what you rejected

[Juan Conejero]

Jack, I look forward to see that image. The object (if it's the same you've sent by private email) is extremely nice!

ImageIntegration's pixel rejection won't work for hot/cold pixels if they are CCD defects, since these are present at the same location on all images. Indeed we would love to have a good hot/cold pixel removal tool (er, Sander?  )

A script to detect single (isolated) hot/cold pixels is very easy to write. I may write one if I find a free while (probability < 0.25)

[Jack Harvey]

Hmmm  If that is the case why did the program identify and reject a column defect present on the chip?

[mmirot]

It would be nice generate a defect map to apply after calibration.

Also, 1.5 rocks!

Max

[Juan Conejero]

Hmmm  If that is the case why did the program identify and reject a column defect present on the chip?

  Because what I've said is not true, of course.  These things happen when one is up at 1 am after a hard day... (and yesterday I was testing integration of flat frames, where sensor defects can't be rejected).

Please ignore my comment; of course hot/cold pixels and other sensor defects are rejected because you have registered the images, and physical pixels don't match since you've dithered between exposures.

[Jack Harvey]

Juan  Thanks for the update.  Appreciate all your help!  When is the vacation so you can get some rest<G>

Looking on the bright side, now you don't have to worry about writing a script for hot pixel reject - which you dont have time for anyway<G>.

[mmirot]

I should send you a set of my kaf 9000 images. It has number of cold/cool columns.
Most, software I have tried don't do a good just of rejecting these type of artifacts even with aggressive dithering. This includes MaxIM, DSS, and CCDstack. I apply interpolation for the bad columns prior to stacking them to fix this. I can never figure out why they are so hard to id and reject.

Max