I just bought a used pre-asph summicron. when I fitted on the hood, I noticed it wasn't straight, so I tried to turn it. however, the whole lens head turned along with it and I can actually unscrew the whole thing. And when I screwed it back, in order to tighten it fully, the apterture mark screws past the centre. Thus, my hood is still not straight, and I am very upset. Is this normal? The lens is still under warrenty by the second-hand dealer. Please help.

-- jonny (jonnytan1234@yahoo.com), July 29, 2001

Answers

I had the exact same problem. Apparantely this is very common in this lens. The kevlar thread in this unit flexes more than the normal brass in other Leica lenses.

The threads are usually locktighted or something similar but because the lens is so small most people mount/dismount the lens with the hood so over time the whole front unit works loose.

Get it back to be fixed at a Leica service centre. It's a quick and easy job for the technician to realign and correctly reseal the 2 units.

When I got mine fixed under warranty the technician said it's common and when fixed won't affect performance.

I did however return my lens as there were other issues. Namely someone less than qualified had opened up the lens previously and left the burs on the screws to show for it.

Cheers.

-- Simon Wong (drsimonwong@hotmail.com), July 29, 2001.

Cost-cutting measures were applied heavily to that lens. Most Leica lenses have grub screws at 90-degrees to the threaded components to prevent unthreading. Both the 35 pre-asph and ASPH Summicrons have an adhesive thread-lock applied rather than set-screws. Perhaps the adhesive is better in the ASPH, or they're just newer, but I haven't heard of the problem with those lenses (yet). My 35/2 pre-pre-ASPH (1973 Canadian) has setscrews and is still 100% tight after almost 30 years; however in fairness that lens has a rotating metal shade so there is no temptation to grab the hood and torque the front group to dismount the lens.

-- Jay (infinitydt@aol.com), July 29, 2001.

The same thing happened to me. Don Goldberg told me that I could glue it back on. I did not feel comfortable doing this , so I sent it to him and had it back in a few days. No problems since then (many years). When you mount and dismount the lens, hold it by the base, not the shade or front rings. Jay Goldman

-- jay goldman (goldman@math.umn.edu), July 29, 2001.

Just so you know you're not alone - I also have a rotating 35 pre- ASPH. I've learned to mount and dismount it using a three-fingered 'claw' grip from the front, so that my fingers hold the hood and all three rings of the lens at once so that nothing can turn relative to anything else.

-- Andy Piper (apidens@denver.infi.net), July 30, 2001.

Here's Simon's posting "Hood/aperature ring alignment out on 35'cron"
(http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=005j Qt).
I too had the same problem as seen in "35 /2 ASPH Summicron M"
(http://www.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=004B v3)

There is for this type of ailment always one simple solution. Take the lens and hood back to the store and get a new hood, and/or trade the whole lens (maybe including hood) for a new one. Being still under warranty has to mean No problem.

Mike

-- Michael Kastner (kastner@zedat.fu-berlin.de), July 30, 2001.

Thanks for all your help. I just sent the lens back to the dealer and he will get it serviced for me.

Mike, where I live, there is no such thing as a refund. Which means what you sited as "no problem" actually is a problem.

cheers, Jonny

-- jonny (jonnytan1234@yahoo.com), July 31, 2001.

I received and unpacked my brand new 35mm Summicron ASPH today, placed it on my brand new M6, plugged on the lens hood, and you guessed it, not straight. It's as though it's screwed on too far. It's straight from the factory. I just hate the idea of anyone (even the most qualified tech) having to fix my new lens. Advice anyone? I thought I'd bought the best!

-- Timothy w Gee (twg@optushome.com.au), August 31, 2001.