OM-4 with Tele-Astranar 400mm f/6.3

[imagemk]

I am having some fun with a 70's Olympus OM-4 and a Tele-Astranar 400mm f/6.3

but I have a couple questions I was hoping someone could help me with.

 

First, on the lens itself it seems there are 2 rings for the aperture and I am

not sure what the second one is for? If you look at the picture I have

attached, the top ring seems to control the aperture, what is the the bottom one

for?

 

Second, is there a way to adapt this lens to my Canon 350D (Digital Rebel XT)?

 

Any help would be appreciated, thanks.

[richard_oleson]

The two rings are both for the aperture diaphragm. One of the rings has click stops, the other one does not. If you set the click-stopped one to the aperture you want to use, then you can rotate the other ring to open the diaphragm for focusing, then turn it back until it stops to close the lens down for the photo without having to take your eye away from the finder to check the lens setting.

 

Another way to use the lens is to set the click-stopped ring to the smallest setting (f/32, I think in this case) so that the other ring is free to turn to any setting - then just rotate the free ring until the meter centers (in manual mode) or until you like the indicated shutter speed (in auto mode) in the finder, and then shoot. This is quicker, though you don't know what aperture you used.

 

Yes, you can use this lens on your Canon 350D. I use one on a 400D as well as a number of different 35mm SLRs. On the Canon, the lens will give good results in manual or aperture-priority (Av) modes, with full metering and auto exosure capability. You can't use program, shutter priority or the green-rectangle setting.

 

To mount the lens to the Canon, you can either buy an EOS - T mount (the mount unscrews off of the back of the lens), or you can get an OM/EOS adapter that attaches to either that lens or any other OM mount lenses you have. I'd go with the latter approach if you have other OM lenses. You can also get the adapter with a chip in it to activate the AF indicator lights to tell you when you're in focus. On the 400 this may not do much, but it is a real help with faster lenses. It does cost quite a bit more than the regular adapter though.

[imagemk]

Thanks for the info Richard, very helpful. I did find a EOS T-mount ring, but there are other lenses that I have with OM-4, so now I am having second thoughts. May get the adapter now instead.

[richard_oleson]

I got a couple of EOS/Nikon mount adapters which let me use all of my T mounts as well as my old Nikkors .... but I just sent off for an OM adapter too so I can add the Zuikos to the list.

 

If you can stand spending the extra money, the adapters with the AF confirmation chip on them are worth it. Focusing on the canon screen can be a strain on the eyes with some lenses.

[john_hermanson2]

For the record, the OM-4 came out in 1984, and it is still a great camera (though it may eat batteries. John