Integration question/issues

This may be because the flats are not applied correctly or are not actually representing the lights well. How exactly did you take the flats, what settings on the camera etc?

@vincent-mod  Thanks for responding, I used the same ISO of 800, I also am using an IDAS LPS-D3 48mm filter.  I am using a Pegasus Astro flat panel as a light source and a T-shirt between.  I used the ASI Air Autorun feature and selected flats with Auto detection. The flats were unusually long at 6 sec each and were a little above 50% on the histogram if I remember correctly

After posting, I was thinking that the 6 secs is way to long for a flat with only a light pollution filter, so I might re try with out the T-shirt and go for around a 2 sec flat and maybe a little below the 50% mark.

Zach

Can you control the brightness on the panel (I guess not then)? Seems like a very dim panel in that case. Around 1-2 sec per flat-sub is a good target to have and getting it to >50% is a good idea as well, not clipping on the right of course, but say 60-70% is a good target to have. If that still doesn't work, I'd be happy to have a look at your data.

Oh and also check if APP is actually using the flats, this should be in the form of a "MF" tag given to each light in the table below.

@vincent-mod Yes, I can control the brightness of the panel.

@vincent-mod I just looked, and yes the MF tag is on each light frame

Ok, so if the flatfield generator is specifically made for creating flats and indeed a nice broadband, evenly illuminated panel, no shirts are required. With the control you can nicely tweak the brightness to match the 1-2 second exposures you're looking for.

@vincent-mod Gotcha, thank you.  I am working on reprocessing with flats that are just under 2 sec, fingers crossed, i'll let you know what happens

I do have a separate question, in the ISO/gain column it shows a -1.0 instead of 800 is that normal ?

Thanks

@vincent-mod well i've tried several different flat runs and I still can't rid of the artifacts.  In fact, one of them actually increases in intensity after processing.  I'll keep trying though, Should i use more flats ? I'm currently using 35, would 50 help ?

@vincent-mod I think I may have gotten my problem fixed :-), Still working on it, However I came up with another question.  Im working on the light pollution section, and I think this looks decent even though ive only worked on part of it.  What if anything, does the corrected model tell me about whether im working in the right direction ?  I hope that makes sense.

 Thanks for any insight

Zach

So what did you change for it make it work better?

If that is the model, it still seems odd, normally you have a nice gradient coming from some light pollution for instance. Not sure what to make of this model, what happens if you don't use the flat and only light pollution correction, and then look at the model?

@vincent-mod  I ended up really just playing with my exposure time.  I'm not sure if its completely correct yet as I can still see some possible issues but its better.  I think i ended up with a combination of around 1 sec and around 50% on the light panel

With the light pollution model I was just trying to see if I was working towards the correct way to evaluate the effectiveness of what I was doing.  I'm not sure what it should look like color wise, the image I posted was only the beginning of me working on the LP.  I'm guessing that i would be looking for an grayish color but I see blue, green, white, etc in different parts.  Hopefully this isn't a silly question, but im trying to improve on my processing skills and I know thatI live in a bottle 6 zone, so even though I am using a LP filter it doesn't block everything 🙂 I started watching the video that Mabula did with the mosaic, and haven't gotten to the end yet, but i didn't see him use the corrected image button, so maybe it is something I don't need to worry about even.  Thank you for any insights that you can share on this

This is what I started with

and this is where I am at with it now, still have some work to do I think, but a definite improvement

Zach

Well, in the end it's about the result you get and that is looking very good! I was just wondering why the model is dropping off so sharply, I normally see that a bit more gradual. Colors in it is normal, there can be color gradients from light pollution as well. A general good workflow is to stretch your image to the max, saturation up to the max as well (background slider also to 0 so you really get the colors there) and then starting with 5 boxes in safe areas (with background), having a look at the result and then slowly adding small boxes towards the problem areas (not immediately on top of such an area). Calculate, check and repeat. That's what works best.

@vincent-mod Thank you, I was wondering the same thing, as to why it was so black on one side, but I didn't get a screen shot of my progress, but as I worked across the image(basically in the workflow description that you suggested), the black went away.  I just wasn't sure what all the different colors meant.   I do have one additional question, if I save a LP correction, can I go back and continue on that same image or do I need to go back to the original and start a new process ?  Thank you

Ah now I think I get why. You placed the boxes only on one side, so APP doesn't know about the data in the other part and makes a best guess. Normally you want to sample the entire image, so beginning with 5 boxes all around.

@vincent-mod  ahh.... gotcha, I was following what Mabula was doing on that giant mosaic in the video he made, but what you say makes sense.  Thank you  Also, im not sure if you say my question, because I edited my post, but ill ask it again.  If I save a LP corrected image, and I later decide that I could do better, can I still run the remove light pollution on that same image or do I need to go back to the original and start over ? 

Thanks

Oh sorry, missed that. Yes, the light pollution correction is non destructive, you can use it as many times as you want. If you think you made a mistake however, I'd advice to maybe start again (like when you placed boxes over nebulosity and such).

@vincent-mod  Cool, thank you. 

@vincent-mod

Good evening, sorry to bug you again, but I developed a new issue that I haven't seen before, and this is the first integration i've done since upgrading to the latest version, but I have strange pixelation or something going on in my image, is this a calibration files issue maybe or am I just using a wrong setting somewhere ?  or maybe I just don't have enough HA data, I am not sure, this is what I processed.  My intention is to combine 9 different imaging sessions, but I have different exposure times and temps so it might not completely work, but wanted to see what this data looked like first.  Any ideas would be fantastic

 camera temp was -15

72 x 300 SII over three nights

48 x 300 OIII over 2 nights

17 x 300 Ha from 1 night.

30 darks, 150 Flats (50 for each filter), and 150 Flat Darks

Thanks

Zach

Does look a bit weird yes, you can combine sessions fine normally. What I personally would do is to process each session on its own (also to keep it simple), using the calibration data for that session and making sure there are no issues calibrating. The end result you can then process. Then combine the data from all the sessions (load in the end result of each session back in as light), no calibration needed anymore then of course. Could you test that with maybe 2 sessions to see if that works?

yes, I will give that a try and let you know how it goes