Altair Hypercam 174M

[IDM]

Hi,
I am using an Altair Hypercam 174M for solar imaging but have a problem with the frame rate when using Sharpcap (both 4.0 and 4.1). The issue being that I cannot get a frame rate above about 55fps. I raised a ticket with Altair and they asked me to do some tests using Altair image capture software, and in those tests the camera was capturing at approximately 120fps.

I have tried everything I can think of in Sharpcap, different USB speeds and altering the memory buffer size and each USB setting with different memory buffer settings and whatever the combination I can't get above 60fps. I have also tried different USB leads and different USB3 sockets, nothing changes the result. Is there something I am missing and a setting I should change to get performance closer to the Altair software speed?

I would be grateful for any thoughts and ideas.

Many thanks,
Ian

[admin]

Hi Ian,

there are about 4 things to check to get the highest frame rate out of this camera

1) Ensure camera is in MONO8 and not MONO16 (or is it MONO12 for that camer) mode - having it in high bit depth will roughly halve the frame rate
2) USB speed control set to maximum
3) Exposure set low enough (ie less than 10ms to allow 100fps)
4) Direct USB connection with USB3 cable and no hubs or extensions

That should get you 100+ fps at full resolution - you can get higher speeds by using ROI (in particular the height of the ROI impacts on frame rate - width has very little effect).

If you are deliberately using MONO12/16 for solar to try to get disc and corona in the same image then 55fps sounds about right .

cheers,

Robin

[IDM]

Hi Robin,
Many thanks for getting back to me.
The camera has Mono 8 and Mono 12, and strangely I get no or very little speed increase when going from mono 12 to 8.
I am definitely using USB 3 sockets as my computer doesn't have any USB2's and I have also tried different cables. The best speed does come with the highest USB speed setting but still a long way short of what the Altair software can achieve.

Is there anything further I should look at in the memory buffer settings? I have tried increasing and decreasing the RAM size but so far to no avail.

Thanks
Ian

[turfpit]

Ian

See viewtopic.php?t=2590
Have a look at this doc. Can you post back your images as shown in the first part plus a table of any tests. The USBtreeview image with your camera connected would be useful at this stage.

Dave

[admin]

Hi Ian,

the memory buffer settings in SharpCap won't affect the speed that SharpCap grabs frames from the camera to any noticeable degree - they are all about what happens when saving images at high speed and the disk/SSD can't keep up with the rate that the images are coming from the camera.

Just a few more things to check

1) Your peak frame rate is stuck at 55 to 60 when just viewing frames from the camera, not saving - if you are saving, lots of other things can impact the rate, which we should try to keep out of the problem for now.

2) You haven't adjusted the 'Frame Rate Limit' setting in the controls on the right have you? Setting that at something like 60fps would cause the kind of effect you are seeing. Try opening the camera with <CTRL> held down to prevent SharpCap from reloading previous settings - that should put things back to default.

Finally, if still stuck, capture a few frames and then post the content of the 'CaptureSettings.txt' file saved alongside the capture here in the forums - that shows all the camera settings being used and lets us see if there is anything unexpected.

cheers,

Robin