Vivitar 75-205 / 3,8 stuck aperture

[Philipp500]

<p>Hi. Sooo, I like the lens, it's not worth much, and googling didn't yield any useful hint, but its aperture is stuck and if someone could help telling me how to fix it, I'd be really thankfull! Thanks so much!</p>

[JDMvW]

<p>I had one that got fungus in it, and found that no still-sane camera repair people will take on disassembly of one of these (or more to the point, the <em>reassembly</em>). Ended up getting a clean one for about $40-50 on eBay some years ago. Older zooms, even the original <a href="http://www.robertstech.com/vivitar.htm">Series 1 cult lenses</a>, are very cheap.</p>

<p>I understand that the real trick is to get the helical threads back together right, so mark things and photograph every step. ....If naphtha (tiny, tiny amounts only) doesn't work.</p>

[Matthew Currie]

<p>I probably can't help with internals much, but for starters, what mount is the lens in? Most mounts other than the screw-mount will default to the selected aperture when removed from the camera. So if you set the ring to the smallest aperture, it should stop down, and the lever in the mount should open it. If it is stuck open, moving the lever might close it. If possible, the first thing I'd do is see if the aperture responds to the lever, and perhaps limbers up. </p>

<p>If the aperture responds to the ring but not to the lever, or if the lever moves freely without affecting the aperture, then it's likely the linkage is broken or disconnected. </p>

<p>If the lens was somehow mounted wrong, or mounted on the wrong camera, it's also possible the lever itself got bent. Make sure it's not rubbing on anything when you move it back and forth.</p>

[User_1172872]

<p>Years ago, I also acquired one that had fungus. JDM is exactly correct... taking it apart was no problem, but I never did get the helical put back together correctly.</p>

[User_502260]

<p>If your 75-205 is the two touch model then it's the one I wrote about some years ago in CameraShopper. It's large and heavy but a decebt performer. I also have at least one example of the two touch model but have not used ot as much. I don't know whether the 2X teleconverters which are marked 75-205/3.8 were made for the two touch model or the one touch model. Some of these lenses have dried up lubricant and it prevents the mechanism from operating. </p>

[Gus Lazzari]

<blockquote>

<p>"then it's likely the linkage is broken or disconnected. - If the lens was somehow mounted wrong, or mounted on the wrong camera, it's also possible the lever itself got bent" <strong><em>Matthew C.</em></strong></p>

</blockquote>

<p><strong>"likely" ?</strong> - Short of impact or tampering, none of that ever happens.</p>

<p>Instead, it's usually the very common and simplest of faults.<br />Somewhere in the aperture mechanism, <strong>lubrication migration and it's age related failure</strong>.<br>

This now bad lube, has very likely congealed.</p>

<p>Being such a low cost off-brand zoom, try a drop at a time of Naphtha along the aperture stop-down linkage/lever, and see if it hits the right spot. It could be the blades that are contaminated or better, the internal ring. If it's the blades that are "wet" with oil, then you'll have to go to "DIY school" and <strong>tear it down from the rear</strong> (No need to touch the front area helical threads/tubes) in order to wash the blades continually until you've sufficiently cleared the blades.<br /> (In theory, they're designed to be absolutely dry of any substance, so no lube needed)</p>

<p> </p>

[Philipp500]

<p>Hi guys, thanks a lot. The lens is the one touch version in Minolta MD mount. It looks new, the linkage is not bent and moves as it should. There is no trace of use, and the glass is perfect. Maybe old new stock. It is stuck wide open. I got it for free and I like it, this is why I'm seriously interested in getting it fixed. I'll try the naphta trick if I can get close to the mechanism. In the end, since I don't have much experience in lens mechanics, I think I'll get a quote to fix it.<br>

Jeff, I do have quite a few Vivitars, including the 70-150 2-touch. I like them all.</p>

[chuck_foreman1]

Well if youR'e sure the lever is not bent. I had just that on a Yashica 135 and the lower stops worked but

jammed at F3.5 . I knew it must be something like that, so sure enough the lever need only a little

pressure IT was hanging against it's track. So it is possible a/p Michael C.

[glen_h]

<p>Old zooms are very cheap at places like Goodwill. They often go on the auction<br>

(at www.shopgoodwill.com) find one close to you to avoid shipping chargers.</p>

<p>I got a Nikon 80-200 for about $10. There are a some newer lenses that are expensive, but mostly you can get very good, and slightly old, lenses for low prices.</p>

<p>To me, the best thing to do with stuck-open lenses is to use them wide open.</p>