Is there something wrong with this source data?

[irtuk]

hey folks.

I recently got myself a ZWO 1600 mono and filter set to up my game from the Nikon D800E I had been using. I have only had one real opportunity to capture some data with it given the longer days but in processing that data I seem to be running into a problem

I have attached the stacked FITS files, I am using astropixel processor and when I get to the stage of combining the RGB channels it's creating this which is, well its very green!

is there something wrong with my source data perhaps? or a focus problem with the green data maybe?

Obviously this is a new camera, new processing software, new workflow so I am not under any illusion this is going to be a one-click process, and I have very little data to work with but can anyone see anything fundamentally wrong in the individual channels?

 

Ed.

 

 

 

M101-ZWO-LRGB4-Blue-session_1.fits M101-ZWO-LRGB4-Green-session_1.fits M101-ZWO-LRGB4-Luminance-session_1.fits M101-ZWO-LRGB4-Red-session_1.fits

[JSeaman]

Your Green, Blue and Luminance have quite bloated stars, I did a quick process by merging the red (quite clean) layer with the stars for the GB+L:

 

[irtuk]

Fair enough, thanks. IIRC I shot red first, then green, then blue then luminance the next night. I don't think I re-checked focus between and the temperatures would have changed a bit. That possibly explains why red is cleanest. This object also moves behind a tree later in the sessions so I am not 100% sure that there's not a leaf or two interfering.

If you can get that result out of that data though, it's obviously mainly something in my processing, my first time with APP, I used DSS for all the Nikon NEF shots so I freely admit I have no idea what I am doing in APP. AstroStace on YouTube has been helpful but, steep curve!

Which processing package did you use for that image? is that Pixinsight? I can see from your sig you have plenty options to go with

 

Ed.

 

[JSeaman]

That really was a quick play and mainly in photoshop, just a dbe in pixinsight which I didn't really need 

I would definitely suggest you check focus on each filter (even if they are supposed to be parfocal), I often have a little tweak to do

The processing is just levels and curves really, this is complicated by the fact that I was masking off the stars using layers but you wouldn't normally need that. eKep going, you're on the right path

[irtuk]

Ahha, ok so I have used the ESA Fits liberator software to get the individual stacked channels into TIFF's that photoshop can read and I can clearly see that the Luminance and Green channels are out of focus. Red is ok, blue is not too bad, G & L are blurred.

Thanks for the pointers. I also managed to work out why "merge channels" is inactive, you need multiple images open in PS before it enables that option. another win!

Ed.

 

[JSeaman]

Cool you're on your way to a fantastic image...

[irtuk]

here we go. this is from APP -> FITS Liberator -> PS and I am fairly happy with is as a first stab at LRGB. Source data needs to be better but for that I need September to come rolling around

Just practice I guess. On AstroStace's channel she downloaded some public data from AstroBin but it seems thats either moved or been taken away. anyone know where there's a raw public LRGB data repository?