Problem Stitching a Mosaic together

Please don't mind the wrong naming of the folders, they are actually the western part of the Veil Nebula

Well just saw I am not using the latest version, will try with 1.054 first

Nope, still an error even wth 1.0.54:

Here is the resulting file (following config St-avg-17102.0s-SC_1_3.0-x_1.0_LZ3-NS-full-eq-add-sc_BWMV_nor-AA-RL-MBB5_4thLNC_it1):

https://www.dropbox.com/s/cx7uv8sq5zsqill/St-avg-17102.0s-SC_1_3.0-x_1.0_LZ3-NS-full-eq-add-sc_BWMV_nor-AA-RL-MBB5_4thLNC_it1.fits?dl=0

Just in case you require the calibration files I used:  https://www.dropbox.com/sh/4lkx4x1br4hjarw/AADC9HRnH1N86HnmHjlmmnzGa?dl=0

Thanks again and sorry for spamming here 🙂

Hi Frank, 

I'll definitely have a look at your data. I'll download it right now 😉

I will try the mosaicing myself and will let you know my findings and hopefully suggestions to get it right.

Mabula

Fabulous thanks!

Hi Frank

Okay, I have had a thorough look at the data 😉

To be able to register the data correctly and robustly I would advise the following:

You can register all frames without the mosaic mode. All frames have overlap with all other frames. In that case, this can be registered robustly in the following way:

1) load all 57 frames of all sessions

2) register using the normal registration mode, enable same camera and optics, enable dynamic distortion correction and increase the scale stop slightly, I used 7.

Mosaic mode technically speaking is only needed, when you have frames that don't overlap with other frames. But if you do enable mosaic mode, try to feed already integrated mosaic panels into APP, instead of loading all frames of all panels. If you load all frames, then the calculations will take very long and won't be better. 

I did not use the calibration frames, only the CR2 raw files,

3) then finally I integrated with MBB at 25% and LNC degree 4th iterations 3 and median integration. Then I did 

• remove light pollution
• calibrated background
• calibrated star colors

Stretched using APP's preview filter with saturation gives me the following:

Registration is fine I think.

Another way to register this robustly in mosaic mode requires saving the camera's and optics optical distortion pattern. Basically, you have 4 field of views

• first night, the 24th is all same field of view more or less, mosaic panel 1
• second night, the 28th is all the same field of view more or less, mosaic panel 2
• third night. the 29th, is split over 2 different field of views half way the session, so these are mosaic panels 3 and 4

Then I would advise, to load 1 frame of all those sessions with different field of views. So 1 of the 24th, 1 of the 28th and 1 of the 29th first field of view and 1 of the 29th second field of view. Register those 4 frames with the calibrated projective model, enable same camera and optics, enable distortion correction and enable save distortion model. Save it with your camera's model name and the name of your optics. 

Then create these 4 panels separately using the following registration settings, enable distortion correction, enable same camera and optics and select the previously saved distortion model. Now the registration uses the saved distortion model in registering the frames per panel.

Then when you have the 4 panels, combine them in mosaic mode using dynamic distortion correction and disabling same camera and optics. Then you should get a robust registration as well.

Let me know if you can duplicate this 😉

Cheers,

Mabula

Thanks a lot Mabula, this explanation is highly appreciated. I always thought I need to put all subs in and then registering using mosaic (it indeed took a while 😀 )

I am integrating right now and let you know about the result. Thanks again!

Just a quick side question:

In the new version, do I still need to apply the selective color after CSC or is this now done automatically?

Best Frank

Your welcome Frank 😉

Yes, you would still need to use selective color after star color calibration. In 1.054 a bug is fixed in star color calibration so the results should be better now, but you can still get a green cast. I am working on better star color calibration. The current version only uses 3 parameters, whereas in a new version it will use 9 parameters (3x3 calibration matrix), then the green cast should be gone as well. So most likely in the next APP version this will be fixed as well , as will the selective color tool, it will be integrated in the left control panel, it won't have it's own window anymore.

Cheers,

Mabula

Awesome. Looks a lot better now, thanks a lot Mabula! Here's the result:  http://www.astrobin.com/309856/D/

Excellent Frank, I am glad you got it working correctly 😉 !

Cheers,

Mabula