Review of new Summarit-M f2.5 lenses

For those that are interested, following last weeks "Leica Hints at Fullframe"

in Amateur Photographer (UK magazine) this week there are reviews of the various

new Summarit-M lenses.

Steve, do they have a website? Are they in-depth reviews? We only get the British

Black and White Photography here, and that has only the occasional and rather

qualitative reviews of lenses. The two major French magazines are sure to review the

Summarits after having tested the complete M Leica line with the M8 last year.

AP has thorough equipment reviews, with contrast and resolution numbers, and had no qualms about pointing out shortcomings. My copy is still in the mail somewhere.

i don't care for those ratings. acording to the leica brochure,you have to close the lens to 5.6

with film bodies to avoid vigneting. that is a useless lens for me.

Useless, I agree, but it seems funny that I'm happy with my slower 35 and 90 2.8s and don't plan on buying the new lenses even used. They remind me of the hassy CB lenses and how well did they do/sell?

I've not bought AP for a long long time now but the reviews are by Geoffrey Crawley (I think that's right) who is very respected for this kind of thing. I'm sure someone on the forum who buys the magazine can report on the findings :-)

I've read the article, the lenses tested well, seems like a good set of lenses for the price and the review is very thorough, covering use on film and the M8, if you're considering buying one I would get the review.

 

http://www.testreports.co.uk/photography/ap/search/subequipsearch.asp?EquipSubType_ID=21

 

They don't seem to be available online yet though.

David, your statement about vignetting is not accurate as a blanket statement. Please consult the data sheets.

 

For the 35mm lenses, the Summarit is the clear winner over the Summicron and Summilux in vignetting.

 

It's a little more complicated for 50mm. The Summicron is the best at f/5.6, followed by the Summilux APSH, with the Summarit coming in third place.

 

For 75mm and 90mm, it's a tie. Vignetting is much less of a problem for long focal lengths anyway.

 

Has Leica let the performance in the "film only" corners of their post-M8 lenses slip a bit? Yes. Smart business move, the M8 is where the money is. But the "film only" corners are still better than their 1950's lenses.

Correct me if I'm wrong, but optically ALL lenses vignette somewhat wide open and stopped down one or sometimes two stops. That's the nature of optics. Whether this makes them "useless" or not is a subjective call.

You don't want to confuse vignetting with cosine fourth power fall-off. Vignetting is caused by a large incursion of the lens body into the off-axis optical path. Usually this is only of serious concern with wide angle lenses. The 50mm Summitar (and later) had a large front group to compensate for this. Cosine fourth power fall-off can be reduced by increasing the pupillary magnification such as in reverse telephotos (retrofocus), sometimes at the expense of barrel distortion.

Alex, you took the words right out of my mouth ;)

Don't confuse "vignetting with cosine fourth power fall-off." Oh dear, I did it again. :)

I guess that the cosine was more powerful than I expected!

Here the last part of IMX (Erwin Puts):

 

http://www.imx.nl/photo/lenstest/summarit_lenses_part_three_.html

 

Well the vignetting on a Summarit 2,5/75mm is neglectible, also on 2,5 or 2,8.

I use it on my M7 without any problems and the quality of this Leica glass is (also) perfect.