SharpCap Forums

Hello Olivier,

You can "open" a camera with all the settings at "zero".
First click the control or shift button, when you click on the camera name for opening,

Jean-Francois

Hi,

sorry about suggesting the darks when you were already using them - I think I saw that the 'dark scaling' was off in your screenshot and misread that as darks being 'off'.

There are two distinct things - the driver and the SDK - and we need to avoid getting them mixed up when discussing...

The driver is a separate installer from ToupTek and gets run inside the Windows operating system to let Windows properly detect and control the camera hardware. However, with modern ToupTek cameras and modern versions of Windows, you *do not need* the ToupTek camera driver (in fact the current version of the ToupTek driver will not load on a fully secured Windows 11 install). The reason that you don't need the driver is that the modern cameras are compatible with a Microsoft provided generic USB driver called 'winusb.sys'.

If you plug your camera in, look in Windows device manager in the 'Universal Serial Bus Devices' section near the bottom of the list - if you are using winusb.sys then your camera will appear in there, probably as 'USB3.0 Camera' (although it might have a model name).

Anyway, if your camera shows up in device manager, either using the winusb.sys or the touptek driver (toupcam.sys), and it doesn't have a yellow exclaimation mark indicating a problem then the driver side of things is fine. To be honest the driver doesn't do a great deal for these devices, just passes requests and data back and forward between the SDK and the hardware.

The SDK is the toupcam.dll file that is installed with SharpCap. This does most of the work of controlling the camera. You may find that you have other copies of the toupcam.dll file on your system as a result of installing the ToupTek ASCOM drivers or other software. SharpCap will always use the copy that it has installed, because that version gets loaded when SharpCap starts up and tries to detect what cameras are connected. That means that other things like the ASCOM driver for the ToupTek wheel will *also* end up using SharpCap's copy of toupcam.dll, which can sometimes cause issues if the wheel ASCOM driver has a newer version.

One thing you can try is copying the different versions of toupcam.dll over the one in the SharpCap folder, but that risks breaking the camera. Another, probably better, option would be to use the ASCOM 'Just A Hub' wheel device in SharpCap, then set up the 'Just A Hub' to talk to the ToupTek ASCOM driver. This makes the control of the filter wheel run in a separate process which removes the clash with SharpCap's copy of the toupcam.dll. If you don't see 'Just A Hub' in the filter wheel list, update to the very latest ASCOM platform.

Going back to the flat correction, any camera settings changes that you have made that have directly or indirectly affected the backgroun pedestal level of the image between dark and light capture will cause issues with flat correction. Have a look at the capturesettings.txt files for the master dark and the light frames to see if something has been changed that might be causing that.

cheers,

Robin

Thanks for the explanation, Robin (and don't worry about the dark frames, it's nothing).

So, I was able to do some more testing tonight, between the clouds

First of all, I'm happy the camera is working well: when I don't connect the filter wheel, everything is fine!


Then, as soon as I connect the filter wheel (FW), it appears... but makes a strange noise, as if it's straining... it doesn't even turn...


...and the image is distorted (without doing anything else, just connecting the FW)!
If I disconnect the FW, it doesn't change anything (each time I turn off the camera and restart SC).
If I specify a different FW in SC, it doesn't change anything.
But as soon as I physically unplug the filter wheel: miracle!
So it's definitely the filter wheel's driver that's causing the problem.

My SC was up to date, but the FW wasn't detected, which is why I (stupidly) installed the "driver pack" from the Touptek website (I shouldn't have!!)... I don't know how to remove it now.

I'll see if I can find the .sys files you mentioned...

Hello Olivier,

Are the filter large enough for not producing some vignetting ?

Jean-Francois

Hello Jean-Francois,


It's 36mm filters, and you see no vigneting on the first image (when the FW is unplugged). The horrible image come when I plug the FW... (even when I don't use it!!!).

I would like to uninstall the FW driver, but I don't know how... (and the chineses don't answer )

Hi,

can you share a link to the exact software that you downloaded and installed as the filter wheel driver? That would help work out any uninstall info.

However, I'm still puzzled - if I am understanding this correctly, just plugging the filter wheel into the USB to the computer causes the problem, regardless of whether the filter wheel is in the imaging train of the telescope and regardless of whether you try to connect to the filter wheel in SharpCap. Is that correct?

It would be very strange for there to be a software side problem of that sort - I am wondering more about issues with USB (bandwidth or USB power issues). How are the USB connections for the camera and the wheel arranged? Does the same thing happen if you try a different USB connection like both straight back to the PC on separate ports or using a hub (ideally powered) for the filter wheel?

cheers,

Robin

Hi Robin,

admin wrote: Wed Nov 12, 2025 3:47 pm can you share a link to the exact software that you downloaded and installed as the filter wheel driver? That would help work out any uninstall info.

It's here: https://www.touptek-astro.com/downloads/


BUT!! Good news!!! I found out how to uninstall it: it was simply in the Windows settings, among the Applications!


So I was able to uninstall that %!¤§ !!

Unfortunately, the sky is overcast tonight, so I can't check if plugging in the FW still disturbs SC (I don't think so, since the cursed driver no longer exists!).

I hope all is correct again, now (except that my filters wheel still hasn't appeared).

I tried specifying the Altair FW in SC... and it works: SC displays the FW correctly! But... it still doesn't work (it doesn't turn) and I haven't been able to check the image quality (the same with "Justhub", it works great, but the FW does not work either).

But I think that, from now, there's no longer an issue with SC and the cursed driver. It's just a FW functionality problem (firmware?) that I need to discuss with Touptek (It's been 4 days and they're not responding, neither on their website nor by email...).

admin wrote: Wed Nov 12, 2025 3:47 pm ...just plugging the filter wheel into the USB to the computer causes the problem, regardless of whether the filter wheel is in the imaging train of the telescope and regardless of whether you try to connect to the filter wheel in SharpCap. Is that correct?

That's exactly it.
Very strange, indeed.

admin wrote: Wed Nov 12, 2025 3:47 pm ...try a different USB connection like both straight back to the PC on separate ports or using a hub (ideally powered) for the filter wheel?

For now, I hope an answer from my friends in China!...

The FW makes a strange noise constantly as soon as it's plugged in. It's not normal. I hope they can tell me what to do... (and that it will start working!)


If necessary, I'll try this solution of plugging the FW and the camera into two separate USB ports, but I hope that will work properly someday; it would be more convenient

Thanks again for your support.
I'll let you know how it goes when I find a solution. It might help someone else in the future.

Clear skies!

Olivier

Hi Olivier,

glad that you are making progress - it does sound like the filter wheel isn't quite right...

I don't have any experience with the Altair/ToupTek wheel, but I do have a couple of other wheels - there is usually a small motor and some way that the motor turns the wheel (a belt perhaps, or a worm gear). There's also usually a magnetic or optical sensor that lets it detect when the wheel is in the right position and also the position of filter 1. When you power up one of these wheels, it usually does a full turn to detect where filter 1 is and get itself calibrated. It sounds like yours may be trying to do this calibration but failing to turn the wheel, and so because it never detects the movement of the wheel it just keeps going. This could also be causing an abnormal amount of power to be drawn by the wheel motor.

One thing worth checking - see if any of your filters are too thick for the wheel and are blocking it from turning - I have seen that happen with some filters. On some wheels it's easy to take off one side of the body to see if anything else may be stopping the mechanism.

cheers,

Robin

Oh, Robin, sorry, I didn't see your reply.

I didn't want to recount my adventures yet so as not to clutter the forum — but yes, I found the solution for the wheel that wasn't turning.
It was indeed a mechanical issue: an elastic band that wasn't in the right place.


I operated, like a surgeon, with tweezers (not practical at all!), and I was able to put the elastic band back in place...
...and now the wheel turns and stops precisely on each filter (when I indicate "Altair" for the FW). Hooray!!

However, the sky is still overcast, so I haven't been able to check with SC if removing the "cursed driver pack" finally allowed me to get correct images when the FW is connected... I'll find out when the sky cooperates

Just a quick note to say everything's back to normal! Phew! And I saw that the new SC update has something for Toutptek's SDK, I'm going to download it!

Thanks again for the support.

Luminance OK
Ha OK: everything is great!
P.S.: Toutptek never replied... Not very nice... So, I'm selecting "Altair" from the filter wheel menu, since I don't see Toutptek! It works perfectly that way.