PixInsight Forum

PixInsight => Image Processing Challenges => Topic started by: mmnb on 2018 June 05 09:15:44

Title: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 09:15:44
Some stupidity and a little bad luck led to the focuser screws coming loose, changing the camera angle midway and giving a funny alignment; as resolved in another thread, moonlight was pretty bad as well (DBE leaves a bit of a dark spot around the galaxy..seems difficult to avoid).  One thing that did go well is that I was able to collect while autofocusing between subs on a nearby star (FWHM for subs seemed significantly improved).

PCC still seems difficult after trying to play with focus length/pixel size (FL: 1371.60, pixel size 9).  Trying to figure out if it is the image quality (FWHM, noise etc.) or the ugly cropped areas that might be interfering with things?

https://drive.google.com/open?id=1BmgayEaRCDwF4dsZuBDhwWgae0FGL2QV
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 09:31:21
Is the problem that it's not plate solving?  I searched for NGC4565 with the Search Coordinates button in PCC, then set focal length and pixel size as you suggested. Works on the first shot for me with the image you shared.

Looks like a good number of your subs are rotated relative to the others. StarAlignment did the right think and lined them up but you're FOV must be pretty tight as you can see the artifacts of it even with a crop. I don't think PCC will solve for that, nor will DBE. Maybe some effort to balance the background variations might help but not sure.
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 10:32:00
Yes, I could not get it to plate solve (perhaps more stupidity in what I am doing than I originally guessed). I'll play around with things a bit more knowing that it should just work (maybe there is a stale setting in there somewhere).

Yes, I think staralign was fine but just trying to do the best I can with this dataset given a lot of things were suboptimal (I think I could only cool to -13C on most exposures on the SBIG 402ME). Taking the wins where one can find them, I am pretty confident about focus now (this was keeping me up at night).
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 10:51:00
For PCC I reset it to defaults before I did what I mentioned above. No settings beyond that.
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 11:22:47
many thanks!
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 11:38:06
Mind post a screen shot? It still doesn't solve after resetting (I searched for ngc4565 instead of using the coordinates from a raw image, just to do it the same way)
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 12:29:34
Sure. Screenshot here:

(https://photos-1.dropbox.com/t/2/AACQuzHDsi9NEGpvGFrICYo5qq_AQ8ZojgXv0wOctzImhg/12/364821068/png/32x32/3/1528243200/0/2/Screen%20Shot%202018-06-05%20at%2012.24.13%20PM.png/EJfu_e8CGLrWGyACKAI/br3NoM2IXeR0c0OahXNLQTTb7nD6AFqpM5oKIos-5H4%2ClhDgb041mJhY8_fQbF6zXPsnZM2hDPxbByYzN0_6820?dl=0&preserve_transparency=1&size=2048x1536&size_mode=3)

I've also attached the process icon with the settings I used. Note that I added a preview to represent the background this time. Also, I ran it on the screenshot you posted. Should work on the original as well.
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 14:14:14
Hmmmm, opening the icon and running it on my xisf (I can see the ROI is defined) still fails...
Did a "check for updates" to be sure with no change...time for some sanity checking on my end.

Logging below case anyone else is watching.  Nothing is jumping out at me..






PhotometricColorCalibration: Processing view: Image29
Writing swap files...
383.935 MiB/s

* Using an automatically calculated limit magnitude of 17.

run -x -p="metadata_focal,1371" -p="metadata_xpixsz,9" -p="metadata_ra,189.0866833" -p="metadata_dec,25.9873917" -p="metadata_epoch,2451545" -p="solver_vizierServer,http://cdsarc.u-strasbg.fr/" -p="solver_catalog,Gaia" -p="solver_magnitude,17" -p="solver_sensitivity,-1" -p="solver_noiseLayers,0" -p="solver_alignAlgorithm,0" -p="solver_distortionCorrection,false" -p="solver_splineSmoothing,0.05" -p="solver_projection,0" -p="solver_catalogMode,1" -p="solver_autoMagnitude,false" -p="solver_showStars,false" -p="solver_showDistortion,false" -p="solver_generateErrorImg,false" -p="solver_generateDistortModel,false" -p="solver_useDistortionModel,false" -p="solver_onlyOptimize,false" -p="solver_outSuffix," -p="solver_projectionOriginMode,0" -p="solver_useActive,false" -p="solver_files,/var/folders/dh/gqpnzzg13tg2_t3952x850rr0000gn/T/PCC_T_8MJWEB98G59X.xisf" -p="non_interactive,true" -p="isGlobalTarget,true" -p="isViewTarget,false" "/Applications/PixInsight/src/scripts/AdP/ImageSolver.js"

Processing script file: /Applications/PixInsight/src/scripts/AdP/ImageSolver.js

*******************************
Processing image /var/folders/dh/gqpnzzg13tg2_t3952x850rr0000gn/T/PCC_T_8MJWEB98G59X.xisf

Reading image:
/var/folders/dh/gqpnzzg13tg2_t3952x850rr0000gn/T/PCC_T_8MJWEB98G59X.xisf
Loading image: w=1530 h=1020 n=3 RGB UInt16
6 FITS keyword(s) extracted.
Seed parameters for plate solving:
   Image coordinates: RA=12 36 20.804, Dec=+25 59 14.61
   Resolution: 1.3540359272238274
Starting StarAlignment iteration
Catalog Gaia already loaded
Catalog Gaia size: 606 objects

Using the triangle similarity algorithm
/var/folders/dh/gqpnzzg13tg2_t3952x850rr0000gn/T/stars.csv:
Scanning star data: done
154 stars.
PCC_T_8MJWEB98G59X:
Structure map: done
Detecting stars: done
75 stars found.
Matching stars: done
10 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #2
useScaleDifferences=true
Matching stars: done
13 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #3
useScaleDifferences=false
* Reference image: Limiting to 125 brightest stars.
Matching stars: done
9 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #4
useScaleDifferences=true
* Reference image: Limiting to 125 brightest stars.
Matching stars: done
11 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #5
useScaleDifferences=false
* Reference image: Limiting to 60 brightest stars.
* Target image: Limiting to 60 brightest stars.
Matching stars: done
10 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #6
useScaleDifferences=true
* Reference image: Limiting to 60 brightest stars.
* Target image: Limiting to 60 brightest stars.
Matching stars: done
12 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #7
useScaleDifferences=false
* Reference image: Limiting to 30 brightest stars.
* Target image: Limiting to 30 brightest stars.
Matching stars: done
12 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #8
useScaleDifferences=true
* Reference image: Limiting to 30 brightest stars.
* Target image: Limiting to 30 brightest stars.
Matching stars: done
9 putative star pair matches.
Performing RANSAC: done
* Previous attempt failed - this is try #9
useScaleDifferences=false
* Reference image: Limiting to 15 brightest stars.
* Target image: Limiting to 15 brightest stars.
Matching stars: done
*** 5 star pair matches found - need at least six matched stars.
* Previous attempt failed - this is try #10
useScaleDifferences=true
* Reference image: Limiting to 15 brightest stars.
* Target image: Limiting to 15 brightest stars.
Matching stars: done
*** 3 star pair matches found - need at least six matched stars.
* Previous attempt failed - this is try #11
useScaleDifferences=false
* Reference image: Limiting to 8 brightest stars.
* Target image: Limiting to 8 brightest stars.
Matching stars: done
*** 0 star pair matches found - need at least six matched stars.
* Previous attempt failed - this is try #12
useScaleDifferences=true
* Reference image: Limiting to 8 brightest stars.
* Target image: Limiting to 8 brightest stars.
Matching stars: done
*** 0 star pair matches found - need at least six matched stars.
*** Error: Unable to find an initial set of putative star pair matches
*** Error: The image could not be aligned with the reference star field
Please check the following items:
The initial coordinates should be inside the image.
The initial resolution should be within a factor of 2 from the correct value.
Adjust the star detection sensitivity parameter, so that the script can detect most of the stars in the image without mistaking noise for stars.
The catalog should be matched to the image. Choose the appropriate catalog and magnitude filter, so that the number of stars extracted from the catalog can be similar to the number of stars detected in the image.
*** The image could not be solved.
This is usually because the initial parameters are too far from the real metadata of the image.

** Warning: Process finished with errors:
  PCC_T_8MJWEB98G59X.xisf: The image could not be solved

*** Error: Failure to plate solve image: Image29
Reading swap files...
842.929 MiB/s
<* failed *>
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 14:51:49
Odd. Can you share the xisf?

EDIT - disregard. I missed that above.
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 16:25:08
OK, sometimes I read to fast. Apologies - I missed the xisf file you linked too above.

Interesting! PCC does not work on the .xisf file, but it *does* work on the screen capture you provided above. Same settings for both (defaults).

Looking at the logs there are clearly differences in what is going on with each. I'm afraid I don't have a quick fix for you.

By the way, I noticed your xisf file has no fits header info that I can see. Maybe there's something off about the file?

Log files are attached for each attempt.
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 05 19:01:54
I should have made the xisf link clearer, apologies.  Didn't realize that the pinpoint routine is robust enough to work in 8-bit depth with the screenshot.

There is no header as the RGB image is the output of several steps, I didn't think the header "carries" as you process. A link to an original raw image (that has coords etc.): https://drive.google.com/open?id=1XBYpe3ocNrPml0H9f2_W9ArZ0MZpTqze
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 05 23:30:44
Hmm. I can't use ImageSolver on that image - same result. Yet, I can solve it in TheSkyX using AllSky:

******** ASTROMETRIC SOLUTION RESULTS ********
Center RA (2000.0): 12h 36m 20.58s
Center Dec (2000.0): +25° 59' 33.8"
Scale: 1.33 arcseconds/pixel
Size (pixels): 765 x 510
Angular Size: 0° 16' 57" x 0° 11' 18"
Position Angle: 183° 10' from north through east
Mirror Image: No
RMS: 1.01 (X: 0.79 Y: 0.63)
Number of Stars Used in Solution: 21 (100%)
FWHM: 2.87 pixels, 3.82 arcseconds
***********************************************


1.33 seems pretty close to what you should get with a f/l of 1370 w/ 9um pixels.

I'm not sure what to say. Probably some tweaking is in order.
Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 02:53:41
OK this is one of those odd ones. While I used 5um pixels that should not be a reason for an image to solve or not. I was able to get this to solve with the ImageSolver script but not PCC. I did have to select a catalog instead of automatic. I then was able to get PCC to calibrate by using the Acquire from Image button. I also selected a preview in the good portion of the image for BN.

What is going on in this image that causes PCC to fail to solve is a mystery to me. No matter what changes I make I cannot get it to plate solve with PCC. The fact that it solves in ImageSolver is the stranger part since PCC solving is based on ImageSolver.


Mike
Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 03:00:11
Just to add I posted this odd problem in the Bug report section linking to this thread.


Mike
Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 03:18:35
Ok I went back reset PCC and set it to the same settings I used in Image Solver and now it works. Maybe it's too early in the morning for me.


Mike
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 06 09:01:39
Mike - you adjusted the pixel size to 5 in ImageSolver and it worked? I get a fail using that. It's saying it only found 2 stars. Were there any other changes?

Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 09:17:54
Greg

The attached screen shoot shows the settings. I changed the catalog also.


Mike
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 06 12:40:45
(thanks to everyone for looking at this)

Odd. I think I've copied the PCC settings faithfully and I still fail.
Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 14:22:38
Ok in my first posting I said I solved the image in ImageSolver script, not PCC. I show those settings which I used the catalog UCAC3, not the automatic setting. With the image plate solved I the used PCC only to color calibrate. I used the button'Acquire from Image' to populate the PCC settings.

The second time I went back, reset PCC, entered my original ImageSolver settings that I used the first time to plate solve and everything works. I just now did the same thing with the same results. Here is the screenshot.


Mike
Title: Re: PCC help...again for ngc4565
Post by: Greg Schwimer on 2018 June 06 15:30:05
I must be missing something. Below are two screen captures:

 - Using the settings Mike did with ImageSolve script. It fails every time.
 - Using the same settings with "Show Stars" checked under Advanced settings in ImageSolve. On the left is the screen shot from the first post, on right is the xisf file.

In the case of the show stars output, the difference is interesting.

Title: Re: PCC help...again for ngc4565
Post by: msmythers on 2018 June 06 16:12:25
Greg try setting the Image Solver script to 1500mm. I just realized that ImageSolver fills in the solved parameters after solving. I used 1500 in the setup, not the 1550.56 in the screen shot. Also you can try PCC with the settings that I showed just above.

Mike
Title: Re: PCC help...again for ngc4565
Post by: mmnb on 2018 June 06 17:48:33
I could replicate successfully running ImageSolve first with the parameters in the earlier screenshot and then PCC works (didn't realize that ImageSolve coordinates stick to the image and PCC will use those).