 Samuel Smith |
quantary lens sam here, i recently acquired a quantery cn mc 500mm mirror lens with minolta mount.was told it would work on my maxxum camera.it mounts fine and sets a shutter speed,but no aperature sets?i've tried aperature priority,to full manual.no aperature is displayed and the shutter won't release.any help? i've spent the last hour doing a search with no help. thanks,sam
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John G. Clifford Jr |
Sounds like this camera doesn't like having a lens attached that doesn't "report back" to the camera about its capabilities. According to the manual for your camera you need to contact a Minolta service center to determine how to use your camera with a "telescope or microscope" (your manual-focus mirror lens can be considered as a telescope for usage purposes). Further reading shows that the camera won't release the shutter until it has a focus confirmation, or the camera is in manual focus mode. So, I'd try putting the camera in manual mode and manual focus (via the manual focus button on the front of the camera) to see if that makes a difference. Note that determining the proper exposure is going to be difficult using the in-camera meter. The Quantaray lens won't be sending aperture information back to the camera body. A quick way to check and see if the Quantaray lens/camera is generating valid exposure info is to put a Maxxum lens on the camera, set it to the same f-stop that the mirror is set to (typically f/8), and get the shutter speed. Then, put on the mirror lens and see if the camera is indicating the same shutter speed. If so, you're in business. If not, you'll need to determine the exposure before pressing the shutter.
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Jon Close |
Ditto John's answer. Some Maxxum cameras have a custom function to over-ride the shutter lock for use with non-Maxxum lenses. Unfortunately, the XTsi - the "Ecstasy" ;-) - isn't one of them. The camera will not display an aperture value for this lens. It relies on an electronic communication with Maxxum-compatible lenses for this information. The mirror lens has no communication with the camera. I don't own a Maxxum, so I don't know whether to manually set the aperture value to "f/8" when metering with this lens. I know with Canon EOS cameras you leave the on-camera aperture value at "00" when using manual and fixed aperture lenses. Re - Metering and comparing to another lens set to f/8, or using an external light meter:
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Samuel Smith |
i did try all your suggestions before asking the question.except upping the aperature.i think like you said it's just not communicating. i've set it before I attach the lens,and no.even the override didn't work.shutter release?i am fine with it.just thought I was doing something wrong.i am impressed with your responses. for I only know what I know. i thank you for your help in my delimma.i even upped my aperature trying a moon shoot tonight,no! thanks so much for your responses.it is so great to have a learning community. thanks,sam
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anonymous A. |
The issue with mirror lenses: no aperture setting! They have a fixed f setting, usually about f8. You need to set the camera manually to a shutter speed which matches the lenses fixed f setting (much as Jon suggested). I have not had to compensate for additional light loss with these lenses, and they do tend to be a bit "soft". I used to own an XT and don't recall a problem releasing the shutter on out-of-focus images when on manual focus. Good luck with the moon.
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Glen Taylor |
I wouldn't hold my breath waiting for answers from Minolta Service Center. Since they've discontinued all film cameras, parts and tech support seems to be drying up as well. The fixed aperture and resolution issues are why mirror lenses are available cheaply on the used market. Most people who get them end up selling them again in short order. That said, the factory brand 500mm mirrors are usually quite a bit better than the Chinese or Korean import lenses like quantaray, promaster, etc. For astrophotography fans, lens compatibility and battery use issues often lead to a good used manual-focus mechanical-shutter camera that can hold its shutter open for hours without using battery power. These are available inexpensively used these days.
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Samuel Smith |
yeah I have tried minoltas service center.i get an email that says someone will get back with me on my problem or question,but no. i think my only way to go is to buy a manual camera. the moon shot was focused,very sharp.the lens was given to me so i'm not out any money. thanks for the info and help,sam oh yeah,in release priority and a minolta lens the shutter will release no matter what,doesn't matter about focus.thanks
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