Need advice on a lens problem

I have a Maxxum 7 that I've been shooting for a while now with Sigma

lenses. Slowly, I've been upgrading to the older minolta glass.

One such lens is the 70-210 f4 which I recently purchased off of

eBay. Nothing is broken or dented, the elements are clear(front and

rear), there is a snappy aperture response, smooth focusing and

zoom, and the general cosmetics are 99%.

 

The problem is that when I developed the 2 rolls of Kodak Tri-X 400

that I shot with it, there is a shadow on the bottom 1/4 of the

negative. The shadow looks like this (with the frame in between the

two vertical lines): _|_/------\_|_ I know it has something to do

with the lens because the shadow is not present in shots on the same

rolls taken with my 35-70 f4.

 

I almost want to say that it looks like the shutter curtain is not

opening completely but I'm not familiar enough with the mechanics to

know if thats possible here. Any knowledge, advice, or remedies you

may have would be greatly appreciated. Thanks.

Could it be a lens is blocking the flash? This matches the description, but you don't say these are flash pictures. Solution: taller flash, or remove lens hood.

To clarify the situation further...These were natural light photographs. Flash was not used. For every shot, the lens had either a Quantaray 1A filter or a Minolta Y-48 Yellow filter and the OEM lens hood attached.

Joshua, can you please upload a photo to this thread so we can see the problem?

Joshua,

 

I doubt it's the shutter curtain or all your photo's will have the same thing happening to them. I too am upgrading to older Minolta glass and have just purchased the same lens off E-bay so I'll be watching the replys. A photo would be helpful. Are you sure your lens hood is the original one? It should be a all metal lens hood. I actually scored (or so I thought) the 70-210 f/3.5-4.5 in what the seller described as "Like New". It was in good shape however the lens didn't have any caps and was scratched up pretty good and it had a piece of lint almost dead center. I've returned it to the seller and waiting for my refund. I just today won a bid for the good old Minolta 70-210 f/4 and well see what condition that arrives in. Do your photo's have the same problem with the lens hood off?

The first two pics here are from my contact sheet. These are both taken with the 70-210 f4<div></div>

These next two pics on the sheet are fine and taken with the 35-70 f4.<div></div>

Looks like the mirror is not fully up when the shutter opens. I don't know why this happens with only one lens.

It has to be the mirror or the shutter.I can't quite tell which way up those pics are but if they are contact sheets they should be the right way up/right way round shouldn't they?

<BR>Anyway a vertical run shutter can leave a shaddow at either the top or bottom of a pic,while the mirror can only block the top.Be carefull judging from back to front negs though,lol.<BR>Has your camera even got a vertical run shutter?

Forgot to add.The lens could possibly be blocking the mirror from lifting all the way.Not sure how though if it is a genuine minolta lens.There's little that one can adjust wrong to have lens parts poking that far back.Not if you want normal focus anyway

I had a look at my 70 - 210 but there is nothing protruding which might stop the mirror.

 

However just a suggestion ... I did note that the rear element on this lens is relatively large - this could make it more sensitive to a mirror sticking part way than a lens with a smaller rear element. That is the stuck mirror would block a significant part of the rear element whilst the 35 - 70 with a smaller element would be unaffected.

 

Hope this helps.

Fire the shutter at low speed or B with the back of the camera open and different lenses mounted to see if the mirror goes up all the way with the lens in question.

Ok - Let's rule out what it can't be:

 

1) Sticking aperture - Wrong shape and it wouldn't cause shadowing.

 

2) Lens hood - It would have to be obvoiusly damaged to cause this.

 

3) Shutter - The Dynax/Maxxum 7 has a focal plane shutter than runs vertically, so in theory this could be the cause, but the shadowing isn't perfectly straight (i.e. it drops off at the edges of the frame) so unlikely.

 

Which leaves a mirror problem...

 

If it's a genuine Minolta lens I can't imagine that it would foul the mirror. If the rear element is protruding beyond the surrounding housing when the lens is zoomed to it's wide end then there's something very wrong! As suggested, set to BULB and fire the camera with the back open to check.

 

If it isn't fouling, and given that the body is working fine with other lenses, the only thing I can think of is some sort of electrical problem. The 7 is virtually a computer with a lens stuck on the front, and reads so much information to & from the lens who knows what could happen if you attached a faulty one.

 

You might need to get a Minolta dealer to check to lens.

I tried opening the camera back and releasing the shutter on bulb as per the suggestions here. It appears that the mirror is flipping all the way up with the lens along its entire focal length. I checked it against my other lenses and the mirror appears to be in the same position. The rear element on the 70-210 is significantly larger than my 35-70 but if that were the cause of my problem then it would stand to reason that other minolta users would be experiencing this problem and that doesn't appear to be the case. I have sent an e-mail to Minolta to see what they can come up with. I don't relish the idea of spending a lot of money at a dealer seeing as I'm a graduate student on a tight budget but it may come to that. Thanks for all of your help so far.

Those pictures are in paris, aren't they? Try shooting a few pictures without the lens hood. I've got the 7, and that lens, with no issues. Do you have another body you could try the lens on? Also, if you've only shot two rolls, definatly try another. Like I said, if it's not the original hood, that could pose a problem. That's all I can figure. Good luck.