QHY268C - Always buffers 3 frames

AmargosaSky
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QHY268C - Always buffers 3 frames

#1

Post by AmargosaSky »

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? Thanks,

Jason
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Re: QHY268C - Always buffers 3 frames

#2

Post by admin »

Hi,

try running the very latest beta of SharpCap 4.0 (https://www.sharpcap.co.uk/sharpcap/sha ... s/4-0-beta) and also switching the 'Force Still Mode' control to 'On'.

In theory this should get around the buffering problem, but there are still issues with the still mode option on some cameras that we are trying to resolve, so it may or may not be a practical fix.

Robin
AmargosaSky
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Re: QHY268C - Always buffers 3 frames

#3

Post by AmargosaSky »

Robin,

Thanks much. I'll try that beta. Do you recommend uninstalling/reinstalling any QHY drivers/sw first, or just install beta? I don't see the need, but checking just in case. Cheers,

Jason
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Re: QHY268C - Always buffers 3 frames

#4

Post by admin »

Hi Jason,

I think just installing the beta should be fine - it will leave SharpCap 3.2 still installed, so you can switch back and forward between the versions without any trouble.

Robin
AmargosaSky
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Re: QHY268C - Always buffers 3 frames

#5

Post by AmargosaSky »

Robin - Thanks for that suggestion. I just tried both the beta 4 and the update to the current production release. The updated production version threw a memory exception error when I tried still mode - and I submitted that error via the UI before it shutdown. The v4 beta won't load the QHY at all and generates the attached error dialog. (FYI I was also getting the attached error when I tried the v3.3 beta). Thanks,

Jason
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Re: QHY268C - Always buffers 3 frames

#6

Post by admin »

Hi,

thanks - I've seen that bug report and already have a fix for it (just a silly thing on my part, sorry). Will try to get a new version out with the fix shortly.

Robin
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Re: QHY268C - Always buffers 3 frames

#7

Post by AmargosaSky »

Thanks for the quick reply and working so hard on fixes! Let me know when/where to download the next release and I'll continue testing the original 3x buffer issue.

Can't wait to get this running and test the new sequencing features once the 3x buffering resolves. You'll leapfrog SGP, etc.

Jason
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Re: QHY268C - Always buffers 3 frames

#8

Post by admin »

Hi Jason,

the new version that has that bug fix in is now available to download - let's hope it actually works rather than just leading us onto another error!

Cheers, Robin
AmargosaSky
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Re: QHY268C - Always buffers 3 frames

#9

Post by AmargosaSky »

Robin,

Thanks! I 'll give it a go tonight and post the results.

Best,
Jason
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Re: QHY268C - Always buffers 3 frames

#10

Post by admin »

Hi Jason,

I've made the change, but it won't be in a downloadable version until (most likely) next Monday. I tend to put out one update a week - otherwise the rate of updates becomes overwhelming.

Cheers, Robin
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