Minolta 50mm f1.7 probs

[dr4gon]

Finally turned that Sig 10-20 back in eh? Hope everything comes back in tip top shape!

[DonSchap]

Yeah ... I hate buying new lenses only to have to return them. It is a little maddening. I have waited and waited ... and SIGMA burns me every time. Well ... 'tis the season to be jolly, right? Fine ... I'll keep their lenses repair staff in business.

4-6 weeks, they tell me.

[DonSchap]

Happily, the two wide PRIMES (Minolta AF 24mm f/2.8 & AF 28mm f/2.8) have been returned to "the bag."

Here was the test on the 28mm that threw me over the top.

B4

28mm @ f/2.8 ... back focus is obvious.

AFTA

28mm @ f/2.8 ... yes, properly aligned!

You can see the focus moved right where it belongs ...

Easy test ... try it out!

[laydros]

Wow, I totally missed this thread when Peekayoh posted it, because I was heads down with exams. Thanks for posting the pics, it's very cool to see the inside. Impressive job of cracking it open and fixing the problem.

Nice to see the fixes on your lenses Don. About how much did it cost for the repairs, if you don't mind me asking?

[DonSchap]

Nice to see the fixes on your lenses Don. About how much did it cost for the repairs, if you don't mind me asking?

Came down to a standard charge of $88.60 per lens, if all they have to do is clean, lube and focal adjustment.

Now, I just (as a matter of fact) took a call from United Camera concerning my KM 24-105mm f/3.5-4.5 and they are quoting a repair cost of $156 and a two/three-week turnaround. So ... you guys might buy your lenses second-hand ... but, the "hidden costs" for these focal adjustments is where they get you.

Remember, this second-hand 24-105 came from B&H Video, basically "as is." I believe I paid around $329 or so for it. So, you tack the repair costs on top of that, and we're back up around the $469 a new one costs! Plus the inconvenience of running the lens back and forth to the repair center and the time you are without it.

"As is" wound up being an unusable lens, in my estimation (worse than the kit, in the condition it arrived in) ... so even dealing with an "established" retailer is chancy. Best advice , buy "new" (with the precious warranty) or from some one you can trust (who takes care of their stuff) and who won't screw you for a buck! "As is" is not the same as "As was!"

But, I have to say ... when they come back from "repair" ... they ARE working optimally. I am assured their focus is "dead-nuts" and that's cool, because of late ... as many of you know, I have had some poor results with OOTB performance, having to return several sealed lenses back to the manufacturer for warranty repair/adjustment. I figure if we drive those costs to them high enough, they may just start investing some time in factory-level Quality Assurance/Quality Control to improve the original product in the box. As always, it is a question of costs ... and having them stop the hemorrhaging is the best business move I can think of.

I have worked in manufacturing for the past twenty years ... and I know that this is an area that can always use improvement. If they can get away with chopping this QA/QC effort out ... THEY WILL! It is "overhead" ... and I will not let them put that cost on me or my family. They get it back, at their cost and they can fix it. I will not allow the store to SWAP it out for a "new" one only to return home and take the chance that it is out of alignment, too. E-gads! Obviously, if it is truly broken, that's one thing ... but, out of adjustment ... it goes to repair.

Sorry, after 50 years of dancin' on the planet ... we do it right.

[laydros]

Peek, I was just looking back at these pictures, and realized that your 50mm doesn't say Maxxum on it. I understand that what we knew as Maxxum in the States was known as Dynax in Europe and Alpha in Asia, so I expected it to say Dynax. Do the European Minolta lenses just not list a brand on them?

[Peekayoh]

They are simply branded, "Minolta" or, later ones "Konica Minolta"

[garda]

The other day the aperture on my Minolta 50mm f1.7 prime stuck wide open. I suppose that after 25years service (I've had it from new), a problem might be anticipated but I was still horrified (like losing a good friend).
The cost of a professional repair is likely to be pretty high so I got a service manual from Pete Ganzel and got to work. Three hours later, after washing the iris blades in detergent I had the whole thing back together. I think lubricant from the Helicoid got on the blades! Why now?
Going to go out now and take some shots to see if it works.

Peter

Hello Peter (and everyone else)! I bumped onto this thread while searching for how to repair my Minolta 50mm 1.7 lens myself. I will use this thread and this link: http://www.pbase.com/pganzel/disasse...xxum_50mm_lens for help when digging into the tricky stuff of unscrewing the lens.

My lens has stuck wide open on aperture 1.7. It works on 1.7 but I cant change it to any other aperture. Since you seem to have the exact same problem, it gives me hope.

Do I need any special tools for removing and cleaning the iris?

I am happy for any hints given in this thread, don't hesitate to give feedback. I plan on doing this before Christmas, if not already this Sunday.

Cheers from a not so wintry Sweden /garda

[Peekayoh]

Garda, hello and welcome.
Usually the aperture just becomes lazy if the problem is down to grease on the iris blades.
There is a spring which pulls the aperture closed and it may be that this has broken or become detached.
You can easily check by moving the aperture lever. Without the spring it will flop about (that's a technical term).

[garda]

Garda, hello and welcome.
Usually the aperture just becomes lazy if the problem is down to grease on the iris blades.
There is a spring which pulls the aperture closed and it may be that this has broken or become detached.
You can easily check by moving the aperture lever. Without the spring it will flop about (that's a technical term).

It seems to be grease on the iris blades. In the first picture (50mm_small_aperture) it seems to be grease on the blades.


The next picture (50mm_aperture_lever) illustrates that the aperture lever stays in the position where you leave it. It does not pull the aperture to be the smallest one.


I'd be happy with feedback on what you think it is, judging from the pictures. Thanks.