Latest 4.1 version with updated ZWO SDK crashes when trying to change ROI on ASI290MM mini

[alphatripleplus]

A couple of days ago (Nov 7) I downloaded the latest 64-bit version 4.1.11251.0 of SharpCap onto my old Windows 8.1 laptop, upgrading from 4.1.11226.0 that I had been using. I used it to create a master dark for my ASI290MM mini to be added to my existing dark library. I immediately noticed that the new dark had been created with a 1936 x 1088 pixel resolution, whereas all my existing darks were done at 1936 x 1096 pixels. I then looked in SharpCap at the ROI setting for the ASI290MM mini, and sure enough, SharpCap had it now set at 1936 x 1088. I attempted to change it in the dropdown menu to 1936 x 1096 and immediately generated a crash report, which I sent in with a comment.

My guess is that something has happened using the new ZWO SDK, as when I replaced vs 4.1.11251.0 with the version prior to the SDK update (4.1.11239.0), SharpCap is back to using 1936 x 1096 default resolution for the camera and all my prior darks can be used.

Here's the crash report file from Nov.7 which includes the "InvalidOperationException" that triggered the crash. Thanks for any help. Hopefully, I don't have to redo all my darks at 1936 x 1088.

Errol

[admin]

Hi Errol,

thanks for sharing - I have seen similar bug reports uploaded but have so far had no clues about what might be causing them, so it's good to have one reported separately so I can ask questions if needed!

I am going to try to reproduce this issue myself to see if I can make it occur.

I did make changes in addition to the new ZWO SDK in 4.1.11251 - I was trying to fix an issue where the displayed resolution for a ZWO might not match the actual resolution in cases where the displayed resolution was ruled out due to various limitations on the size of the image, the amount of binning in use and whether 'hardware binning' is on or off. It sounds like that change is at least part of the cause of this.

cheers,

Robin

[alphatripleplus]

Thanks for the super fast reply, Robin.

Hopefully, you can reproduce the issue.

Errol

[admin]

Hi Errol,

no luck so far, but I have some ideas.

Can you check your previously saved image/dark files for me with a viewer application to see what the resolution really is. I think that previously SharpCap was running the camera at 1936x1088 but showing 1936x1096 on the display for the capture area Fixing that issue may be part of the problem.

Can you make the crash happen every time that you try to change from 1936x1088 to 1936x1096? If it's repeatable I might need to go out and buy one of the 290 mini cameras just to get to the bottom of the issue!

cheers,

Robin

[admin]

Hi,

Ok, quick update... I have reproduced and fixed the crash, but I am still thinking the camera was really running in 1936x1088 previously without showing it. Not yet sure how to deal with that issue properly.

cheers,

Robin

[alphatripleplus]

Hi Robin,

Very interesting. I just checked the png images that I captured last night with the 290MM mini and SharpCap 4.1.11239.0 and they are in fact actually 1936 x 1088 when examined in Nebulosity, although SharpCap is showing them as 1936 x 1096 - which is exactly what you suspected.

I also used ZWO's ASILive 1.9.1 software to capture a couple of targets last night, and Nebulosity shows the jpg files that ASILive creates as being 1936 x 1096 not 1936 x 1088. (I haven't updated that version of ASILive for a few months, so I doubt it is using the latest SDK).

Thanks.

Errol

[admin]

Hi Errol,

thanks for that, I think I know what is going on then...

ZWO as I previously mentioned has rules about the valid values for width and height of frames - for instance the height has to be even and the width a multiple of 8 (more complex with binning involved). There is also an additional rule that the number of pixels must be a multiple of 1024, which is supposed to apply to USB2 based cameras but not USB3 ones.

I now suspect that the multiple of 1024 rule doesn't apply to newer USB2 models like the 290MM mini, as that is probably internally the same as the USB3 normal 290MM. Applying that rule was making SharpCap change the resolution to 1936x1088 instead of using 1936x1096.

Now, we combine that with the fact that until the last update, SharpCap still displayed 1936x1096, even though internally it had changed to 1936x1088, which made the bug difficult to spot unless you went looking at the properties of the saved image files. My first attempt to fix the issue with displaying the wrong size caused the crash, which I now have resolved in my code here.

Since your camera obviously works fine at 1936x1096 in ASILive, I am going to disable the 'multiple of 1024' rule for cameras with 'MINI' in the name, even if the ZWO software tells me they are USB2 - hopefully that will give access to full resolution without breaking other cameras like the 120MM/MC which does need the 'multiple of 1024' applied.

cheers,

Robin

[alphatripleplus]

Thanks for the explanation, Robin.

I think you are right that the "multiple of 1024 rule" from ZWO may not apply to their newer USB2 cameras, as I have the newer ASI220MM mini guider with the SC2210 sensor that has 1920 x 1080 pixels. I've not used that one with SharpCap, but I'm guessing SharpCap might have used the rule to change its resolution too.

I will definitely try both the 290MM mini and 220MM mini with SharpCap after you release a fix. Thanks again for the help.

Errol

[alphatripleplus]

Hi Robin,

I just tested the latest 4.1.11294 64-bit with my 290MM mini and the camera is now recognized as 1936 x 1096, and changing the ROI no longer causes a crash. However, I did notice that I will have to redo all my previous darks taken with earlier versions of SharpCap, as the latest version reports my previous darks do not match the 1936 x 1096 resolution of the new lights in 4.1.11294. I'm guessing this may affect other ZWO camera too.

Errol

[admin]

Hi Errol,

I think it will only affect the 'mini' versions of the cameras that are USB2 connected but USB3 tech internally.

If you set your camera to a custom resolution of 1936x1088 then you could continue to use your old dark/flat files I think,

cheers,

Robin