My Schmidt-Cassegrain illuminated finder scope

[omaroo]

Hi all

I've just purchased a 500mm Vivitar f/8 Schmidt-Cassegrain mirror lens cheaply from a member on my local forum in Australia. It had a Pentax threaded ring mount so I adapted a Nikon bayonet mount and attached the lens to it. Luckily the internal thread on the bayonet ring matched the lens thread. So - I have a 500mm lens for the camera. They're not brilliant terrestrial lenses, but at 500mm anything is going to be tricky to get to perform well.

Anyway - I went a step further and adapted a spare Nikon extension tube that I had lying around to create a mountable "body" for the lens, and one that could also carry my Orion illuminated reticle.

Success! The unit works very well with the reticle, so I intend to mount it on my Celestron C8 and give it a go soon. Focus is a bit critical, but once I find infinity reliably I'll be OK I guess.

Good bit of fun. Don't know how practical it'll be, but there you go...

Cheers

Chris

[centroid]

Innovative idea Chis.

Hope your ingenuity, is successful.

Dave

[barkis]

Chris.

I too bought myself a 500mm mirror lens, but I got mine from a local camera shop a number of years ago. It is a Russian 500 f5.6

It will work on the sky OK. It came with three filters too, but I added a solar screen to one of them. The last time I used mine was on the last lunar eclipse. I took a series of the eclipse stages, and the generous moderators on SGL were kind enough to award me SG POTW. I was over the moon with that (pun intended.).

I intend to use the lens a lot more with both my DSI and DSLR cameras, come the dark sky season.

I will post a couple of pics here later.

Ron.

[Cloudwatcher]

That looks a useful piece of kit,Ron. Works well judging by the eclipse pictures. Have you used it for any wildlife shots?

I think you must have bought that lens during the 'Cold War' era as in closeup it appears to have come with a built in spy!

Looks like he's using the Zorki copy of the Minox spy camera!

CW

[barkis]

That looks a useful piece of kit,Ron. Works well judging by the eclipse pictures. Have you used it for any wildlife shots?

I think you must have bought that lens during the 'Cold War' era as in closeup it appears to have come with a built in spy!

Looks like he's using the Zorki copy of the Minox spy camera!

CW

I would make a very poor spy C Dubya, I would be picked up 5 minutes into the mish.

The cam is a Fuji Z1 a very nice little number.

No wild life from me, but I have a friend who does a lot of it. He is well into covering the Ospreys that come into the Lake District to breed. Most of his work is video. I don't know how much longer he will carry on. He was at Ullswater last week. He had his car parked well on to a grass verge whilst imaging something or other, when some pea brain tore round the bend, lost it, and wrote his, and my mates car off. He was none too pleased I can tell you. But, lucky he wasn't sitting in it.

Ron.

[omaroo]

Excellent Ron!

I'm keen to see some work you've done with it.

I notice that my lenses' collimation is out of kilter slightly. Stars are not especially round. Do you know if there is a way to collimate these lenses? Is the cap on the corrector removable and are there screws under it? I notice that there are three screws on the back of the lens - right on the primary's periphery - are these the adjusters? I couldn't imagine that the manufacturer would have no way of getting this right without a way to adjust it.

Cheers

Chris

[barkis]

Well Chris, I am afraid the only image I have is the lunar eclipse one.

All the other shots with the lens, were take on slides, and I don't have a slide scanner anymore. Besides, I have had such a clear out of old stuff that has accumulated over the years SWMBO issued an ultimatum. And you know what that means. More frightening than my old drill sergeant.

Anyway. here is the picture I hope they all forgive me for showing it again.

Ron.

[omaroo]

No apologies required here Ron. That's a very nice panel of images indeed.

Yes - the Finance Minister in my household insists that I take out the old stuff too

Thanks for posting