This seems to be a well known problem, posts about go back to 2021. I tried NINA for capture and no buffering, the first frame was right there as expected. With SharpCap it takes 20 minutes to get the first 5 minute sub frame. Since it works fine with NINA, it seems that the problem is with SharpCap. This post from 2021 describes the problem perfectly:
"I have been using Sharpcap for about three months with no real issues, with an ASI294MC Pro. I recently got a QHY268C, and SharpCap always captures three frames in the background before eventually displaying the first frame, then second frame, so on... the counter in the lower right passes the initial exposure time and counts negative for the sum of the other two frames before the first frame appears. Then the counter behaves as intended, but the displayed image is always three subs "behind".
For short exposures like focusing or plate solving this isn't a big issue. However, for longer exposures (for example 5 min subs) this is detrimental because I have to wait 15 minutes to see the first 5min frame appear. Then, any changes I make require 15 more minutes (the 3x 5 subs buffered) to even see the first new frame. By then, it's time to focus again and so on... I've got some 10-30min sub projects planned, but they aren't feasible under these circumstances.
I've tried playing with the DDR buffer settings, USB speed slider, USB3 vs. USB2, but none seem to have an effect to get real-time image loading like I'm used to on the ASI294MC. I tried reinstalling the latest QHY drivers and that didn't have any effect. I tried the beta version of SC but that doesn't load the camera at all (different issue, but not central to this thread).
I am not sure if this is a QHY hw/settings issue or a SharpCap issue.
Has anyone else encountered this, and is there a solution?"
I like SharpCap and prefer it to NINA. I have found that if I plan for the delay, it isn't a problem unless I decide to change the camera settings, then I have to start over again. Has anyone found a solution? Thanks.
268C Buffers 3 Frames
-
admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: 268C Buffers 3 Frames
Hi,
did you try the option for 'Force Still Mode' set to on and/or putting SharpCap itself into still mode? I thought that typically resolved this issue as it stops the camera from running in video mode and therefore avoids the buffering of frames internally in the camera/QHY software.
cheers,
Robin
did you try the option for 'Force Still Mode' set to on and/or putting SharpCap itself into still mode? I thought that typically resolved this issue as it stops the camera from running in video mode and therefore avoids the buffering of frames internally in the camera/QHY software.
cheers,
Robin
Re: 268C Buffers 3 Frames
I just finished testing, still mode does the job - thanks
-
admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: 268C Buffers 3 Frames
Awesome, thanks for confirming.
I will see if I can work out a way to automatically switch into still mode for longer exposures and then back to video mode for shorter ones.
cheers,
Robin
I will see if I can work out a way to automatically switch into still mode for longer exposures and then back to video mode for shorter ones.
cheers,
Robin
-
admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: 268C Buffers 3 Frames
Sadly, auto changing for QHY is not possible 
The reason is roughly as follows...
* QHY make more capabilities of the underlying sensor available to applications like SharpCap
* One extra thing that is available is the ability to set capture to include extra pixels around the edge of the sensor in still mode - some of these are for calibration purposes
* Because of this, on some QHY cameras live mode and still mode have slightly different resolutions (different by a few pixels up to about 16 pixels)
* I cannot use the ROI feature of the camera to make the two the same because the smaller resolution is offset somewhat into the larger *and there is no way to find out the offset amounts*. Without getting the offset exactly right things like dark frames would work incorrectly if they were captured in live mode and then used in still mode (or vice versa)
* Since the resolutions have to be different, SharpCap cannot seamlessly switch between live and still mode when the exposure changes.
Fortunately other manufacturers like ZWO, Altair, Player One, etc have taken the approach of not making the extra rows of pixels available, meaning that all the complexity above does not apply and that SharpCap can switch happily between live and still mode (typically live mode for exposure below 2s and still mode above that point).
cheers,
Robin
The reason is roughly as follows...
* QHY make more capabilities of the underlying sensor available to applications like SharpCap
* One extra thing that is available is the ability to set capture to include extra pixels around the edge of the sensor in still mode - some of these are for calibration purposes
* Because of this, on some QHY cameras live mode and still mode have slightly different resolutions (different by a few pixels up to about 16 pixels)
* I cannot use the ROI feature of the camera to make the two the same because the smaller resolution is offset somewhat into the larger *and there is no way to find out the offset amounts*. Without getting the offset exactly right things like dark frames would work incorrectly if they were captured in live mode and then used in still mode (or vice versa)
* Since the resolutions have to be different, SharpCap cannot seamlessly switch between live and still mode when the exposure changes.
Fortunately other manufacturers like ZWO, Altair, Player One, etc have taken the approach of not making the extra rows of pixels available, meaning that all the complexity above does not apply and that SharpCap can switch happily between live and still mode (typically live mode for exposure below 2s and still mode above that point).
cheers,
Robin
-
Jean-Francois
- Posts: 402
- Joined: Sun Oct 13, 2019 10:52 am
- Location: Germany
Re: 268C Buffers 3 Frames
Hello Robin,
The extra pixels are useful ... I used it last year for some measurements with my QHY268 camera at RAL.
The problem is that the detector dimension changed between the video or the still mode (... bad idea from QHY).
Ideally is that the user has the choice ... all the video with or without the extra pixel and all the still images with or without the extra pixel.
The most of the user will have the camera without the extra pixels.
But for more scientific work, it is useful to have the extra pixels around the detector.
The most annoying thing was for me last year, that I did the images with the extra pixels ... except a sequence of images.
It was a long work to "fit" the images with the other.
Regards,
Jean-Francois
The extra pixels are useful ... I used it last year for some measurements with my QHY268 camera at RAL.
The problem is that the detector dimension changed between the video or the still mode (... bad idea from QHY).
Ideally is that the user has the choice ... all the video with or without the extra pixel and all the still images with or without the extra pixel.
The most of the user will have the camera without the extra pixels.
But for more scientific work, it is useful to have the extra pixels around the detector.
The most annoying thing was for me last year, that I did the images with the extra pixels ... except a sequence of images.
It was a long work to "fit" the images with the other.
Regards,
Jean-Francois
-
TigerClaw35
- Posts: 23
- Joined: Fri Jun 18, 2021 6:33 am
Re: 268C Buffers 3 Frames
Hi,
yes, it is a well known problem but not only because SharpCap Software. Today I finished my new Photonewton and installed a new PC with SharpCap and also upgrades the QHY 268C with newest firmware. But same problem. I kcannot understand why QHY sells something like this. You pay 2000 EUR and more for nothing. With new QHYCCD AllinOne Software there is no Buffer on/off button in SharpCap anymore. So there is no possibility for a workaround. Normally if you choose exposure and push buffer on and off, it works fine. But with newest software nothing works. And QHY was so nice to remove the old AllInOne Software so I cannot use it anymore.
Because Force still mode: As I post this problem in older topics it does not work or makes SharpCap crash during LiveView.
Best regards,
Raul
yes, it is a well known problem but not only because SharpCap Software. Today I finished my new Photonewton and installed a new PC with SharpCap and also upgrades the QHY 268C with newest firmware. But same problem. I kcannot understand why QHY sells something like this. You pay 2000 EUR and more for nothing. With new QHYCCD AllinOne Software there is no Buffer on/off button in SharpCap anymore. So there is no possibility for a workaround. Normally if you choose exposure and push buffer on and off, it works fine. But with newest software nothing works. And QHY was so nice to remove the old AllInOne Software so I cannot use it anymore.
Because Force still mode: As I post this problem in older topics it does not work or makes SharpCap crash during LiveView.
Best regards,
Raul
-
admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: 268C Buffers 3 Frames
Hi,
unfortunately the QHY cameras are some of the hardest to work with in some ways - that's because many of the models have their own quirks of the sort that you have encountered - they don't all behave exactly the same. I have about 5 or 6 different QHY cameras here to test with and I can get all of those to work fine because I can find and deal with the quirks if the have any. I don't have a 268 to test with, so I have to rely on bug reports and end-user reports to try to determine what is going wrong and what (if anything) can be done to deal with it.
I have just checked my uploaded bug report archive and can't find any recently (last 10 days) that are linked to the 268M or C, so I guess the issues you had were not uploaded or you were using a version of SharpCap that is older than my bug report filter allows for.
If you do get a chance to upload a bug report (or send it manually) from either the latest SharpCap 4.0 or 4.1, I will see if there is anything I can do about the crash in 'Force Still Mode'. I don't think I can do anything about the 3 frame buffering as that is part of the QHY side of the code.
cheers,
Robin
unfortunately the QHY cameras are some of the hardest to work with in some ways - that's because many of the models have their own quirks of the sort that you have encountered - they don't all behave exactly the same. I have about 5 or 6 different QHY cameras here to test with and I can get all of those to work fine because I can find and deal with the quirks if the have any. I don't have a 268 to test with, so I have to rely on bug reports and end-user reports to try to determine what is going wrong and what (if anything) can be done to deal with it.
I have just checked my uploaded bug report archive and can't find any recently (last 10 days) that are linked to the 268M or C, so I guess the issues you had were not uploaded or you were using a version of SharpCap that is older than my bug report filter allows for.
If you do get a chance to upload a bug report (or send it manually) from either the latest SharpCap 4.0 or 4.1, I will see if there is anything I can do about the crash in 'Force Still Mode'. I don't think I can do anything about the 3 frame buffering as that is part of the QHY side of the code.
cheers,
Robin
-
TigerClaw35
- Posts: 23
- Joined: Fri Jun 18, 2021 6:33 am
Re: 268C Buffers 3 Frames
Hi Robin,
sorry for my late response.
Yesterday I installed the new AllinOneDriver from QHY and also newest SharpCap. First I got a message "Opening this camera via ASCOM may reduce performance ....". I think the reason was because I installed new driver and uninstalled the old one. SO IO forgot to install the ASCOM support.
So I reinstalled it. But in SharpCap I got the warning that current system driver is 21-2-20 but the software need version 21-9-15 or later. But why? I have the newest QHY drivers.
At the end the camera worked fine. I enabled Force Still Mode and frames seems to work fine. Sometimes it shows me at the bottom of SharpCap 2 of30 frames in use or 1 of 30 frames in use (Memory).
But I discovoered that max. Pixel are 6252x4176. But as I remember it is not the value which QHY wrote in his specs. And what I also discovered is that if I set exposure to 10s it loads 11 or 12 seconds and after that it starts with next frame. But I think this is normal?
Best regards,
Raul
sorry for my late response.
Yesterday I installed the new AllinOneDriver from QHY and also newest SharpCap. First I got a message "Opening this camera via ASCOM may reduce performance ....". I think the reason was because I installed new driver and uninstalled the old one. SO IO forgot to install the ASCOM support.
So I reinstalled it. But in SharpCap I got the warning that current system driver is 21-2-20 but the software need version 21-9-15 or later. But why? I have the newest QHY drivers.
At the end the camera worked fine. I enabled Force Still Mode and frames seems to work fine. Sometimes it shows me at the bottom of SharpCap 2 of30 frames in use or 1 of 30 frames in use (Memory).
But I discovoered that max. Pixel are 6252x4176. But as I remember it is not the value which QHY wrote in his specs. And what I also discovered is that if I set exposure to 10s it loads 11 or 12 seconds and after that it starts with next frame. But I think this is normal?
Best regards,
Raul
-
admin
- Site Admin
- Posts: 13344
- Joined: Sat Feb 11, 2017 3:52 pm
- Location: Vale of the White Horse, UK
- Contact:
Re: 268C Buffers 3 Frames
Hi,
did you install the 'Beta Ver 20230412' version of the QHY all-in-one? I think that may contain newer drivers than the 'stable version', which may help get rid of the system driver warning. Unfortunately the system driver warning comes from the QHY SDK code, so it's not something I can turn off in SharpCap
The additional time taken for each frame is normal when running a camera in still mode - it is the time taken for the camera to respond to the request to start a new frame added to the time taken for the frame to be downloaded to the PC when is has been completed.
cheers,
Robin
did you install the 'Beta Ver 20230412' version of the QHY all-in-one? I think that may contain newer drivers than the 'stable version', which may help get rid of the system driver warning. Unfortunately the system driver warning comes from the QHY SDK code, so it's not something I can turn off in SharpCap
The additional time taken for each frame is normal when running a camera in still mode - it is the time taken for the camera to respond to the request to start a new frame added to the time taken for the frame to be downloaded to the PC when is has been completed.
cheers,
Robin