[Solved] QHY5L-II-C question. Is mine assembled correctly?

[ofranzen]

Hello. I got a QHY5L-II-C with a mount/scope package I bought second (or third) hand and have been having problems with poor guiding sensitivity. The camera was mounted to a regular skywatcher 9x50 finder scope with an extender and can focus. It can however only focus with the locking screw on the finder scope removed so the objective can be screwed in almost to there the threads end.

I started looking through the equipment I got and pictures online and this got me a bit confused. The previous owner had the "c adapter" on the camera and then fitted to the finder. The "c adapter" if I understan correctly has some AR coating and seems to also block IR. At least it looked like it when I used a remote and phone camera. Then I found a ring and a piece of clear glass that doesn't seem to have either coating or IR filter. They were both in the camera box and it looks like the glass had been glued in the ring but has fallen out.

So my guess is that the "c adapter" should actually be used for planetary imaging/video and this other ring that fits in its place should be used just to protect the sensor when guiding. This "clear glass ring" is shorter than the "c adapter" which would also I'm hoping get the camera to focus with the focuser screwed in less so I can put the locking ring back. There is some foam rubber around the sensor that pushes against the loose glass so I don't need to glue it back in.

Is this correct? See photos taken with a potato below.

Thanks in advance

/Ola

Edited September 22, 2020 by ofranzen
Adding solution.

[StuartJPP]

I think what you have got there is the standard "C" mount with IR filter that was supplied with the early QHY5L-II cameras as well as a "CS" mount as well.

The CS mounting is shorter and allows CS mount CCTV lenses and finderscopes with shorter focal point to be used.

As far as I am aware the newer versions of the cameras are supplied with a CS mount as it is easier to attach a 5mm CS->C adapter/spacer if needed.

Depending on what lens/scope you are attaching to the camera you may need one or the other to achieve infinity focus.

My QHY5L-II camera also had a 1.25" extension tube supplied as well if needed (about 30mm long), though I haven't had to use it yet.

If you are stuck you could ask Bern at Modern Astronomy, he's a really helpful chap.

[ofranzen]

This is most likely a very early versionof the camera so it seems you are quite right. I'll just give it a try with the clear glass next time I get a chance and see what happens. I should focus better if nothing else and maybe I can get better sensitivity too.

[Adam J]

17 minutes ago, ofranzen said:

This is most likely a very early versionof the camera so it seems you are quite right. I'll just give it a try with the clear glass next time I get a chance and see what happens. I should focus better if nothing else and maybe I can get better sensitivity too.

I have a prototype version and its got an odd arangement on the front I ended up putting a nose extender on it and threading on a 1.25 inch IR filter.

Works well.

Adam

[ofranzen]

I had a chance to try it now and yes, with the clear glass instead of what I think is filter for planetary use, I can achieve focus in the finder with the locking ring in place. I can't say for sure that I got better sensitivity too but I have never polar aligned with Sharpcap this fast before.