PDA

View Full Version : Minolta AF Macro Lense - Depth of Field Preview



TheodoreJay
12-12-2007, 01:21 PM
I'm a bit green as to camera mechanics. I have noticed on my Minolta AF Macro lense that the Depth of Field Preview button doesn't always function proprely. When I detached the lense and flip it over I notice that on my other AF lenses the visible shutter/appeture flips to closed position (you can open back up manually by flipping the lense lever). On my Macro lense this shutter/appeture lever sticks in the open about 50% of time (seems like a faulty spring mechanism).

-Is there any easy cure for this or should I take this lense to the repair shop?

-Does this affect camera performance (I still seem to be able to take digital picutures anyways).

Thanks for anyhelp in advance. TheodoreJay (Denver, CO)

coldrain
12-12-2007, 01:50 PM
My guess is that if the DOF preview button does not always work with that lens, also it may go wrong at times while making a photo, since both times the aperture gets closed via the same mechanism?

It is "lens" by the way, not "lense". "lense" is just something weird that is creeping into internet language the last few years. So, lens.

No idea wht a repair would cost, and no idea if it is worthwhile or if a new macro lens might be interesting either... that is for you to decide. Such issues are a bit hard to resolve yourself though.

SONYNUT
12-13-2007, 11:26 AM
Take It Apart See If The Spring Fell Off..

TheodoreJay
12-13-2007, 01:13 PM
Well per Sonynut I am tempted to take it apart but it's a very complicated lens. My experience is the minute I take it apart it will turn into a big mess.

Yes it's repair time for the 50mm macro lens. I can tell when the shutter is working properly because then the DOF (depth of field) button functions.

Simple experiment using same camera settings, with shutter mechanism working properly a small aperture long time exposure looks pretty good and when the shutter mechanism is not working I get a way over exposed picture (shutter doesn't spring back to the expected small size and stays way to open). Also, if I quickly switch to a simpler 50mm lens the exposure is just fine using the same camera settings.

My guess is allot of moisture on the shutter blades or the spring mechanism is worn (started to notice the problem in Hilo, Hawaii where the humidity is really high). Lesson cameras parts don't like moisture and yes the shutter lever on the back of an SLR AF type lens is critical to a proper exposure.

Thanks for the thoughts guys.

SONYNUT
12-13-2007, 09:23 PM
Then Get A Picture Of It Being Smashed By A HAMMER. ;-)

DonSchap
12-13-2007, 09:45 PM
I have a lens repair place near the house ... and they turn around a lens in about 25 days, depending on the severity of the repair. I figure $85 for anything routine ... like cleaning or adjustment.

Parts replacement ... I've had it go as high as $175 for the full gutting of a 50mm f/1.4 ... but, it depends on the how sophisticated the repair and lens, also. Most of the things I've had done were fixed focal length lenses ... spring replacements and blade cleanings. The usual stuff.

The work is usually warrantied for a full 90 days, so when you get it back ... you should use it right away, just to be sure. Tossing it right back into your camera bag, without real use, would probably be a mistake. :)

TheodoreJay
12-27-2007, 02:51 PM
Took the lense over to the friendly neighborhood Wolf camers store.
Turns out most lense cleaning/maint. is a standard charge of $154, pretty good for a lense that will cost me at least another $400 new.
Lesson learned if the DOF button is not working your appeture is probably screwed up as well. Explains all of the over exposed shots when I try to get better depth of field with long exposure time and small appeture (the appeture is not actually closing down to the right size).