Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
I just bought an older Rokkor manual camera lens - how do I test aperture mechanism?
I recently bought an older Minolta Rokkor 58mm f1.2 manual camera lens. However, it appears that the aperture mechanism is either not working, or missing altogether. I am wondering how to test this - I want to make sure it is defective before I try to return it since I will end up eating the shipping charges. I have an older manual SRT 101 body to use in the testing process if that helps.
EDIT: I can't seem to get it to work using the method you described. If I take the lens off the camera, set the aperture ring to a smaller aperture (e.g. f16) and use my finger to slide the black aperture tab on the rear of the lens, should the aperture diaphragm close down inside the lens?
I don't raelly care about the camera (no offense to any old school manual shooters out there) - it is the lens I was after.
EDIT #2: I planned to convert it to EOS to use on my Canon DSLR. Unfortunately, it seems that the aperture is completely trashed. When the camera is set to take pics, the depth of field preview doesn't do anything through the viewfinder (or looking into the front of the lens), firing on "bulb" with a small aperture setting while looking into the front of the lens (and with film 'back door' open to let light through), the lens stays wide open. I can't even see any aperture blades inside it when I look closely, so I think that part of the lens must be missing entirely. I planned to shoot wide open with it anyway (that's kind of the point of buying an f1.2), so I am debating whether or not I'll keep it.
EDIT #3: I appreciate all the advice.
I have contacted the seller to see if he has any interest in rectifying the situation (ie. refund some of my $$), but I suspect that it will be returned in the end. I eat the back and forth shipping charges, but I tend to agree with you - I might as well get a fully functional lens if I am going to the trouble of converting it.
As for existing Canon lenses - the 50mm f1.2 L is about $1200, while the rokkor 58mm f1.2 manual is between $200 and $400. Since I am on a budget yet want the speed and shallow depth of field of an f1.2 lens, the manual lens path seems like the best choice.
Cheers and thanks again.
1 Answer
- QophLv 51 decade agoFavorite Answer
Put it on the camera, put your camera on B (or the slowest it goes), and fire. The diaphragm won't move on some lenses (most lenses after screw mounts) to incorporate open-aperture metering. So that your viewfinder doesn't darken, but the camera still meters for your selected aperture. If you didn't know. Oh, and it looks like you have a DoF preview button to the top-right of the lens mount. If that is indeed what it is, that will help. You won't have to release the shutter.
[Edit] That is the lens release button. All right, this is from the manual: "MC Rokkor lenses are designed with a meter coupler which permits them to remain wide open during viewing, focusing, and exposure setting. In order to check your depth-of-field when using these lenses, push the diaphragm button on the camera body after the aperture has been set.
When using other Rokkor lenses designed for the Minolta SR 1, SR 3, or SR 7, use the preview button on the lens barrel or the camera's diaphragm button. When the diaphragm (stop-down) button is pushed, after you advance the film, the diaphragm closes down to the pre-set aperture and locks. When the button is pressed again, the diaphragm fully reopens."
Here is the whole manual:
http://www.butkus.org/chinon/minolta/minolta_srt-1... [End edit]
[2nd edit] Well the reason I said to do it on the camera is that it definitely should work that way. Either with the DoF preview button (to the bottom-left of the mount, looking from the front, it goes in sideways) or by firing the shutter. Look through the viewfinder when pressing the DoF button to see if the scene darkens. If you can't see the blades, maybe this will tell a different story. If not, then you probably got a non-working lens.
Alternatively, you could put it on the camera you wish to use it with (digital?) and take some shots with different apertures and just see if it changes anything. You'll need to be on manual, of course. What are your plans for this lens, anyway? [End edit]
[3rd edit] Personally, I would not keep it. Yes, you might want it for its great, wide aperture, but that doesn't mean you'll want to change your lens just to use a smaller aperture if you need or want to. It's one of only two functions on a lens. It should work. Isn't there a Canon lens that will work on it already, so that you don't have to do any iffy work on the lens (unless it only requires an adaptor)? [End edit]
