rob pfile Posted October 21, 2023 Share Posted October 21, 2023 i note that the calibrated frames from SPA-1-CMOS look like they have a flat correction error: you can see that on the left the frame is dark, and on the right, the frame is light. there is also a large circular artifact that spans the whole frame. i suppose the problem could be related to the moon, but i see this problem in most of the L 1-click observations using this telescope as well, and they can't all have the same moon proximity. i found that the flats for SPA-1-CMOS, at least for the L filter, are 10 months old. it seems like maybe new flats would be in order? thanks, rob 1 Link to comment Share on other sites More sharing options...
ERNESTO GUIDO Posted October 23, 2023 Share Posted October 23, 2023 Hello Rob, Yes, we'll go for new flats for SPA1 as soon as possible. Please consider that we never separate the camera and OTA and all our telescopes are covered under roll-off-roof observatory. So there's no assembling/disassembly of setup every night and dust is a minor issue. This means that flats once made are very stable up to 7-10 months. While we usually try to do new flats every 3-4 months, in some periods there is a bigger gap. Clear Skies, Ernesto Link to comment Share on other sites More sharing options...
rob pfile Posted October 23, 2023 Author Share Posted October 23, 2023 yes, understood - my own system is very stable and i can use flats for a long time. however something is wrong here and i do think it is possible that new flats will not solve the problem, but it is a necessary first step in debugging the problem. thanks, rob Link to comment Share on other sites More sharing options...
ERNESTO GUIDO Posted October 23, 2023 Share Posted October 23, 2023 Yes, I agree. We'll check with the new flats. But it seems some sort of vignetting has recently appeared producing the black halo at the edge of some of the frames. We are investigating the cause. Clear Skies, Ernesto 1 Link to comment Share on other sites More sharing options...
rob pfile Posted November 7, 2023 Author Share Posted November 7, 2023 any updates on this? thanks. Link to comment Share on other sites More sharing options...
ERNESTO GUIDO Posted November 9, 2023 Share Posted November 9, 2023 Hi Rob, We are making some technical changes to SPA1 that we hope will improve its performance, next step will be new flats. Clear Skies, Ernesto 3 Link to comment Share on other sites More sharing options...
Craig Schultz Posted November 17, 2023 Share Posted November 17, 2023 Ernesto, I have noticed this too. On one-click observation from Nov 16 2023: https://app.telescope.live/click-grab/details/7443 it clearly shows dark corners, but looking at the individual subs it might just be the flats being rotated incorrectly during calibration. Notice how the blue subs have light corners on the left and dark corners on the right. I'm wondering if the flats were rotated 180 degrees or flipped horizontally to the image and then applied if that would correct or at least minimize the current issue with flat field correct since the new camera came online. Once the flats are worked out, will you be going back to recalibrate existing data? Since the setup is stable, I'm hopeful the new flats will work to correct previous data into a more usable state. Blue Sub Composite preview from one-click: Link to comment Share on other sites More sharing options...
rob pfile Posted November 24, 2023 Author Share Posted November 24, 2023 i noticed the same thing about the newer images, the overcorrection in the blue channel only. i think it would be pretty strange for any preprocessing pipeline to rotate a flat 180 degrees, and it seems to me the problem must lie elsewhere. but of course stranger things have happened. hopefully there will be some updates on this soon... Link to comment Share on other sites More sharing options...
ERNESTO GUIDO Posted November 24, 2023 Share Posted November 24, 2023 Hello Craig, Thanks for your suggestion about a possible automatic calibration procedure. That shouldn't be the problem because nothing has changed in the routine that handles the calibration, but anyway I'm going to take a closer look at this. While this vignetting issue in the corners of the frames has not yet been solved (and we are very sorry for that) I just would like to point out that this very dataset has been used by R. Asmußen to produce this amazing image he posted in the gallery a couple days ago: https://telescope.live/gallery/nebulae-and-dust-perseus Clear Skies, Ernesto 1 Link to comment Share on other sites More sharing options...
Dan Thompson Posted November 29, 2023 Share Posted November 29, 2023 Bringing my comment over from the other thread I created on this topic (sorry for the duplicate thread). The problem is worse than just vignetting, as there is significant ringing in the images, particularly in the blue channel, as has been noted. In any case, as has been said, new flats should resolve the issue. Thanks for working it out for us! Dan 2 Link to comment Share on other sites More sharing options...
Liam Quinn Posted December 11, 2023 Share Posted December 11, 2023 Could someone look at CHI-1 please - I've got about 23 x 5 min Oiii sub data and it will not go through WBPP with the calibration masters - fails at measurements I suspect maybe the master files need refreshed or I am missing a setting in WBPP. I've another near 40 or so coming on down in the next few days that might help but I doubt it. Link to comment Share on other sites More sharing options...
Daniel Heyer Posted December 13, 2023 Share Posted December 13, 2023 Nothing can be done with the spa-1-cmos corners/vignetting but if you download the raw frames and raw calibration frames and calibrate on your own you get a better result. Something is up with the calibration method the Telescope Live calibration software. Link to comment Share on other sites More sharing options...
Daniel Heyer Posted December 13, 2023 Share Posted December 13, 2023 On 12/11/2023 at 12:16 PM, Liam Quinn said: Could someone look at CHI-1 please - I've got about 23 x 5 min Oiii sub data and it will not go through WBPP with the calibration masters - fails at measurements I suspect maybe the master files need refreshed or I am missing a setting in WBPP. I've another near 40 or so coming on down in the next few days that might help but I doubt it. Did you download the raw fits files? The raw fits files are compressed using RICE compression and PixInsight can not open these files. You have to open the raw files in Siril and save decompressed versions that work in PixInsight. Link to comment Share on other sites More sharing options...
Liam Quinn Posted December 14, 2023 Share Posted December 14, 2023 2 hours ago, Daniel Heyer said: Nothing can be done with the spa-1-cmos corners/vignetting but if you download the raw frames and raw calibration frames and calibrate on your own you get a better result. Something is up with the calibration method the Telescope Live calibration software. Thank you for the info Link to comment Share on other sites More sharing options...
Liam Quinn Posted December 14, 2023 Share Posted December 14, 2023 2 hours ago, Daniel Heyer said: Did you download the raw fits files? The raw fits files are compressed using RICE compression and PixInsight can not open these files. You have to open the raw files in Siril and save decompressed versions that work in PixInsight. good to know thx Link to comment Share on other sites More sharing options...
rob pfile Posted December 15, 2023 Author Share Posted December 15, 2023 (edited) On 12/13/2023 at 3:45 PM, Daniel Heyer said: Did you download the raw fits files? The raw fits files are compressed using RICE compression and PixInsight can not open these files. You have to open the raw files in Siril and save decompressed versions that work in PixInsight. you can also use Jarmo's python program to uncompress the files. it works really well. Edited December 15, 2023 by rob pfile Link to comment Share on other sites More sharing options...
rob pfile Posted December 28, 2023 Author Share Posted December 28, 2023 has there been any work to resolve this problem? i see that on LRGB images the problem still exists in the one-clicks... Link to comment Share on other sites More sharing options...
ERNESTO GUIDO Posted December 28, 2023 Share Posted December 28, 2023 1 hour ago, rob pfile said: has there been any work to resolve this problem? i see that on LRGB images the problem still exists in the one-clicks... Hi Rob, This dataset has been taken at the request of many users because of the special rendez-vous between comet 62P and the Leo triplet galaxies. The full moon was only 40-50 degree away, in normal condition we never use LRGB filter with full moon in the sky. So what you see is the result of this very special condition. The target is at the very centre where the frame is perfect, here a crop is all you need. As regards SPA1 vignetting, the problem is not related to the flats. Below you can see an image where the same target imaged with same filter & exposure time shows the issue on December 5 but not on December 09. Clear Skies, Ernesto 1 Link to comment Share on other sites More sharing options...
rob pfile Posted December 29, 2023 Author Share Posted December 29, 2023 ok, that's fine (about the moon). i guess i'm just asking if the problem was worked on and resolved, or not? are you implying that sometime between 5 Dec and 9 Dec that some work was done to fix this problem? Link to comment Share on other sites More sharing options...
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