Info request for Angenieux 20-120 t3 and London Cine lens maintainence and service

[J G Harding]

Hello all,

 

This is my first post,

 

I'm one of those shooting director types, I do both on different projects, for corporate and promo and sometimes narrative, and I'm looking forward to discussing lots here.

 

My first question for this respected community is this: is there anywhere or anyone in London who can take a look at old cine lenses?

 

I have a 1972 Angeniuex 20-120 t3. It works great from 35-120, an ancient feel to the images that I love and a soft painterly look wide open, but anything wider on the zoom and it's crazy fuzzy until things are very far away. Close focus just disappears completely.

 

Also it's not even close to parfocal, though I don't know if that's supposed to be the case to be honest, as information is hard to find.

 

The zoom markings are out of whack so it's clearly been repaired at some point...

 

I'm using on an OCT19 to EF adapter from ciecio7 on eBay, currently with Canon APSC, and intend to use with the Blackmagic 4K whenever it turns up. :huh:

 

Any assistance or links in diagnosing what's up (if anything) would be greatly appreciated, many thanks.

 

JG

[Dom Jaeger]

You have an Angenieux zoom with an OCT19 mount?

 

The symptoms you're describing sound like a back-focus problem. If the lens isn't seated at the correct distance from the sensor it won't hold focus through the zoom range, getting worse as you go wider.

Edited April 16, 2013 by Dom Jaeger

[J G Harding]

Hi Dom, thanks, indeed I do. I know there aren't too many mounted like that. Comparing with a Lomo I have with both OCT19 and PL mounts I can swap, it looks about right flange distance, but of course about right means nothing here does it! It may need some fiddling.

 

I have yet to check infinity focus too, I've only tried close focus so far, but I assume if it's a back focus issue as described then I will be able to go past infinity at the wide end and not reach it with the tele end?

[J G Harding]

I'm guessing it's probably too far away from the sensor then...

[Dom Jaeger]

If the back-focus is out it throws both ends out the same direction but at 120mm it's much less than at 20mm. If the back-focus is too short you'll go past infinity (and lose close focus at the wide end), if it's too long you won't reach infinity (and only have close focus at the wide end).

 

For a zoom to properly hold focus it needs to be collimated to within one or two hundredths of a mm, several times less than the thickness of a human hair. It sounds like whoever fitted the OCT19 mount to your lens may not have done a proper job, or possibly your adapter is badly out of tolerance. The OCT19 flange depth is 9mm longer than a PL mount.

[J G Harding]

Thanks for all the tips so far,

 

I've heard plenty of good reports about this adaptor and the lens is clearly well used, so it seems likely that the lens is the culprit and back-focus could do with adjusting. I'll check focus with that Lomo on this adapter too and get back.

 

It's not that I can't use it like this for most of my purposes, to be honest, but if I can find somewhere in London or nearby to get it looked at and adjusted for this EF mount adaptation that would be ideal...

 

I guess I'm on to the second part of my query then: where to find someone to have a look...

Edited April 16, 2013 by J G Harding

[J G Harding]

Well, I removed the mount and got it closer to working using the collimation ring that screws back and forth and trial and improvement. It's not perfect but it's better... Still hunting for someone in London who can deal with such lenses if anyone has any tips.

[Stuart Brereton]

He's not in London, but Les Bosher should be able to do this for you.

 

http://www.lesbosher.co.uk/

[Guest Owen Parker]

Another option, again not in London I'm afraid, is True Lens Service in Leicestershire.

 

http://www.lensrepair.co.uk/

[Guest Owen Parker]

Wouldn't you Adam & Eve it!

 

Not 10 mins after posting the above, I came across this firm in London.

 

http://opticalsupport.co.uk/products/index/lenses/17/service-repair

 

At least you've got some options now...

[alan doyle]

les bosher is amazing but stupid slow no matter how easy the job..

never less than 3 months..

true lens are strutting super models wanting top dollar and long wait.

lots of in out exhales huff puff vague pricing until you are hooked in.

optical support charge fat fees and take forever.

 

bernie o in america is ex sammies uk understands all these lens and will not bullshit you or keep you waiting forever.

 

you want uk go with les for a long wait.

uk is badly served i am afraid for quick ish turnaround on movie gear

http://www.super16inc.com/

Edited May 24, 2013 by alan doyle

[Robert Lewis]

I have to say that my very recent experience with Les Bosher was outstanding.

 

I live in the UK, some 120 miles from Les' workshop. I needed the mount changing on a Zeiss 10-100mm 3.1 lens from an Arri standard to an Arri Bayonet. I called him and arranged to go and see him two days later. He changed the mount immediately, checked over the lens, collimated it, and generously offered me a cup of tea! I was on my way home within 90 minutes. What more could one wish for?