Fiting a lens to a CCD

[pmrid]

I have an old (USB 1) SX HX916 which I think would make quite a good guidecamera if fitted with a lens. It has what I think is the old Pentax thread nosepiece (42x1 thread I believe) and was wondering whether anyone else had succeeded in mounting a lens direct to a CCD such as this. It seems a shame to waste such a sensitive camera when it will otherwise just sit in the scrap heap.

Peter

[Tandum]

Peter, the sensor is 17.5mm back from the front making it the same as the newer SXV-H9C. The handbook for the SXV-H9C (http://www.starlight-xpress.co.uk/Handbooks/SXV-H9C%20handbook.pdf) shows a 25mm spacer is required to fit a pentax screw lens to the camera (page 6). However, the HX916 manual (http://www.starlight-xpress.co.uk/Handbooks/HX9%20handbook.pdf) shows a 27mm spacer to connect a pentax screw lens (page 5). I don't understand why they are different.

The newer camera has an M42/.75 thead on the front instead of an M42/1 thread as you have on that HX916.

Or, these guys (http://www.gerdneumann.net/v2/english/eng_adapter_all.html) list a T-Thread(Female) to M42/1(male) adapter.

[gbeal]

If the adaptor you have is M42x1 on the front, it is most likely the "real deal" and will space most "Pentax" M42 lenses correctly, so try it and see. If it doesn't, I can send you the correct one, I think I have a spare (somewhere).
Try something like a 50/2 Pentax lens, you'll like it.
Gary

[pmrid]

The only adapter I have is (sadly) unsuitable. It's one I had Peter Tan make up for me to take the old ST-7 (that I still have here somewhere). It's only 21.5mm and it has the wrong thread (42..75). So Gary, if that offer of yours holds, I'd be delighted to take it up. Let me know the $$. I'll sort it out with you in 3 weeks when I get back from my wanderings in Europe.

Peter

[gbeal]

Send me an e mail Peter, I just looked, can't find yours, that way we can take this off-group. I'll go look for it.
Mind you just re-reading your listing, it appears I "may" not have what you seek. Anyway, let's converse in private and we will work something out.
Gary

[pmrid]

Just wandering through a terrific flea market over here in Budapest and found a 27mm spacer AND a 135mm F3.5 lens for $A30 bucks. Deal of the week.
Peter

[gbeal]

Ha, then you are set, it should all fit together as required, well done.
Gary

[Terry B]

This might be a stupid question but why does it matter what distance you set the lens as long as it is less than the distance to achieve focus at infinity?
If it is closer, don't you just focus the lens as needed?

[gbeal]

Not stupid at all Terry, unless you are using the likes of the Hasselblad lenses, the FLE40 springs to mind. In that the elements move relative to each other. as the lens focuses closer they move to reduce/minimize the inherent aberrations.
With Ye Olde Pentax M42 though, I suspect this doesn't happen. Not at AU$30 anyway.
Gary