I'm trying to figure out how to mount my solid catadioptric lens to my Nikon D3100 DSLR. The lens is a Vivitar Series 1 600mm f/8 catadioptric lens. Are there lens adapters that would facilitate this? Also, although I can't see why it wouldn't, will the camera work with this lens? The lens is entirely manual. Finally, would it be possible to use a tele-extender with this lens/camera combination? If so, what would be good recommendations?
What type mount does the Vivitar lens have? Vivitar lenses are available with mounts for most SLR/DSLR camera brands, so yes, it's likely you need the proper adapter. You will likely have no metering in addition to everything else being manual.
There's one out on eBay for sale. Seller says it's a "T" mount. If so, the mounts are screw on using three small lock screws to hold in place. "T" mounts are still available. eBay shows them from a couple of bucks, up to about $10. I've used the Nikon 500mm f8, but never was impressed. Images were a bit soft, and any out-of-focus light pinpoints turned into doughnuts.
According to the following link, (File:Vivitar Series 1 Solid Catadioptric 600mm f8 lens.jpg - Wikimedia Commons) the lens has a M42-.75 rear flange. Don't quite know what that means, but I assume it's diameter and thread count. In any case, I assume I need some sort of adapter that allows me to connect the lens to the camera body. According to another site (Nikon D3100 - Wikipedia), the Nikon D3100 has an F-type mount. Everything seems to be talking about T-type mounts, but I have no idea how that compares to F-type. Just as an aside, I currently have an adapter on the lens for an old Pentax camera. I have no idea what type of mount that has, although the back of my memory is whispering K-mount.
The M42x.75 mount is for a T mount, and the .75 designation is the thread pitch. THIS IS NOT THE SAME AS A PENTAX M42 MOUNT. The T mount was an economical means of attaching lenses made for Vivitar, and others, to attach to dissimilar camera bodies. They're made, generally, for Pentax screw and K, Nikon F, Canon, and others. Most allow for metering, and focus to infinity. You only need to get the appropriate T Mount for a Nikon "F" mount, and your lens will fit your D3100. Since there's no meter coupling you'll only be able to control exposure through the shutter speed. It all depends on what generation your Pentax is. Pentax changed from M42, to the K mount in the mid-70's, and there are adapters which allow the use of M42 Pentax, to bayonet mounts for Pentax, Canon, Nikon, etc.
T- Ring adapter (For Nikon - Taiwan), w/inside threaded front end, on a Nikon DSLR. I use it to mount my DSLR's to my telescope's focusers m,y screwing a nosepiece or barlow lens to the T-ring.
Depends on what you mean by Old Pentax mount. I had the ME Super from the '80's and it was the K mount. I had a 500mm cat lens for that camera, the lens was T-mount and came with the adapter for the Pentax K mount. All it needs to mount to Nikon is a T-mount adapter for Nikon F-mount. The f/8 lens was difficult to focus on that manual focus camera with its big viewfinder and good focus screen, so I expect it will be even harder to focus on the D3100. I only had a 2x extender at the time and I am sure I tried to use it with the lens, but it must not have worked as I don't remember having taken any pictures with the TC/cat combo.
T-mount is an adapter as described by KmH. I currently have my D40X on a Celestron 127mm goto Cat telescope using a T-adapter. About $15 or less for one online. You will not get metering, and there is no aperture. And of course no auto focus. S0, your looking for a Nikon T-mount adapter. I don't recommend a tele extender. Even a 1.4 will take you to an F/11. Very hard to get a good focus with that dark of a aperture. With the 600mm lens on your 3100. Your already getting a 900mm effective lens length. Camera shake will be very hard to control. Except with a very sturdy tripod and head, and remote release, or use of self timer. But if you really want too. The t-adapter will connect to a tele extender and then the tele extender to the camera body. But your going to have a very hard time focusing, and holding it steady for no camera shake to show up.
Any 2x converter will likely severly degrade the image, AND will also lower the f/stop's numerical value by a factor of two full f/stops!!! This means that the f/8 will drop to f/16....VERY "slow" for a 1200mm effective focal length. Plus, the view through the pentamirror viewfinder nsyetm of a D3100 will by abysmally DARK with a TC added. The solid catadioptics lenses, the 450mm and the 600mm sold as Vivitar were well-made and pretty good quality; perhaps two of the better catadioptric lenses of their era. The D3100 will have to be set to M for Manual exposure mode, otherwise it will not shoot images. YOU will need to set the right ISO value and shutter speed to get the correct exposure, and your D3100 will NOT show any light metering information. Since the D3100 is a fairly modern d-slr, instead of using a 2x converter and degrading the image, I woulkd suggest cropping the images shot with the plain lens, at its native 600mm length, rather than using a 2x teleconverter; teleconverters ALWAYS have at least some penalty for their use, and sometimes that penalty is minimal, but most of the time, a 2x converter carries a steep penalty in image performance, PLUS the two full f/stops' woeth of lost light can often be a very bad penalty, especially in a long, long lens like a 600mm, slow-aperture lens. You need a T-mount for Nikon F adapter, to go onto the rear of the 600mm lens; this T-mount is a simple device, held on by the three small set-screws. This used to be a commonly-sold item, but might be a bit harder to find, but with the 'Net, it is easily locatable on-line.
On the back of the lens, should be a "T-mount" adapter. It screws onto the lens, and will unscrew. Just get a Nikon T-mount adapter, and replace whatever adapter is currently on the lens, and you are good to go. Digital cameras do not have a focusing screen that makes it easy to focus a manual focus lens. So you will have to practice manually focusing the lens. If you have not use a manual focus lens, it can take a bit of practice to get it.
