How to remove red and green hot pixels?

[mostlyemptyspace]

Hi all. I'm new to PixInsight. I've been going through several tutorials and have had some luck so far. I have an old Canon 1000D and it has a lot of noise. One thing I noticed is that normal noise I can seem to get out with TGVDenoise. Sometimes, however, I get these really prominent red or green pixels and I can't seem to get rid of them. I tried using this CosmeticCorrection tool for preprocessing and it didn't work at all. In fact, it made the red and green pixels bigger. It appears that these pixels are visible in the original subs, but they become more noticeable after stacking. Any tips? Thanks!

[Duncan]

Also new to PixInsight, but just finished dealing with some hot pixels similar to what you describe in my trial image set myself.

I had quite a lot of nasty blue/green hot pixels showing up in my final image on the first run through, but was able to take care of them by going back and using cosmetic correction (I hadn't bothered on my first run through). It required a fair bit of experimentation to get the right settings, but once I got the hang of what each of the controls did everything worked. In my case, I have separate subs for each color channel, and applying CC on the individual frames right after calibration worked just fine.

What's the procedure you're using?

Duncan

[mostlyemptyspace]

When I tried CosmeticCorrection it didn't seem to do anything. I followed a tutorial on the subject, and the hot pixels actually got larger when I used CC.

[pfile]

make sure you are doing CC on unregistered frames.

second, you can do a real-time preview with CC and watch how the hot pixels are being removed as you move the sliders. to do this, open the CC process and load your master dark into CC. then click "enable" under "hot pixels threshold". now open your target image and define a small preview on it. make sure your target image is frontmost (blue title bar), then click the open circle at the bottom of the CC process. this will bring up the real-time viewer, but it will be set to the entire image. switch the real-time viewer to the preview you defined, and then mess around with the level slider on CC. you should see the hot pixels disappear at some point along the travel of the level slider.

rob

[Duncan]

I also found it helpful when using the real time preview to check the "Show map" checkbox. Then I can switch off the "hot pixel" and "cold pixel" and enable them one at a time so that I can see exactly what is being removed while I play with the slider control, before switching back to the full image preview.

Duncan