In a recent deleted thread about the adventures of film,travel and food; the 90mm Contax G series short telephoto was mentioned...

I have never used this lens but have know of people who bought the Contax G system just for this lens.....It was listed by Popular Photography as the best 90mm lens ever tested.........Several posters on the deleted food and film thread had negative comments about this lens....What are your opinions of this lens; and do you have any photos to post to show us what you mean; besides wild adjectives..regards Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 26, 2002

Answers

What can I say, the Contax 90mm is superb! I have just sold my G system, but ALL the Contax lenses are equal, or better, to Leica equivalents. And the only reason I sold my Contax G2 system is the body. It was simply not 'in synch' with my photographic needs. Annoying focus problems spoiled a great set of lenses.

-- Steve Barnett (barnet@globalnet.co.uk), May 26, 2002.

The best 90 mm ever? I don't know, but definitely beautiful. Better than Leica? Again, I don't know, but probably in the same league. Just like the sharp V/C screw mount 90 mm, BTW.

-- Olivier (olreiche@videotron.ca), May 26, 2002.

I have both the Leica 90/2 ASPH and the Contax 90/2.8 with a G2. My perception, without doing any kind of objective testing, is that the Leica 90/2 ASPH is a better lens. I could find some photos to post, but frankly there's no difference that you'd be able to see on a monitor. I also find that I can hand hold my M6TTL/90 Summicron at a slower shutter speed than I can the G2/90 2.8. I don't have any explanation for this. I agree with Steve that all the Contax G lenses are excellent lenses, including the 90, but I don't know why anyone would buy the G system just for that lens.

Dale

-- Dale Griffith (dgrif55@aol.com), May 26, 2002.

The Zeiss 90 is neck-and-neck with the current Leica 90 Elmarit for sharpness. The Leica wins center of the frame at 2.8, but the Zeiss holds up better in the outer areas where the Elmarit has some MTF fall- off. Since the APO 'cron is a notch ahead of the Elmarit it doesn't surprise me to find that someone thinks the APO beats the Contax, too.

ALL Zeiss lenses are very hot/contrasty, and also somewhat pink, compared to Leica's average - but the 90 Elmarit is one of the 'Zeissier" Leica designs. IMHO.

My Sonnar weirded out - it would focus correctly and then revert to the rest position BEFORE the shutter opened instead of after - resulting in nothing but pictures focused 'out there' somewhere beyond infinity.

Not the optics' fault - but it did persuade me that I wanted a system where **I** made the decisions about WHAT focused WHERE - plus glass that was a lee-tle kinder and gentler on contrasty film like Velvia - hence the move to Leica.

I'm working on some postable pictures from my past with the G lenses - if there were no Leicas I'd go back to the G/Zeiss combo like a shot....

-- Andy Piper (apidens@denver.infi.net), May 26, 2002.

Pop Photo also tested the Leica 90mm f2.0 APO, and called it the best short telephoto they ever tested. Acually, the best short telephoto is the Nikkor AF-D 85mm f1.8. Anyone that has one of these beauties, or has used one, knows exactly what I'm talking about.

-- Glenn Travis (leicaddict@hotmail.com), May 26, 2002.

I use both the G 90mm and the Leica 90 Elmarit (current type); I find them pretty much equal. I certainly wouldn't select one or the other system based on just that lens.

One thing I've seen among many Contax users since the camera first came on the market is that they don't use the camera _as a rangefinder camera_ or iow, they just aim it in the general direction not being very careful about what the AF area is seeing to actually focus on. I've always used the Contax just as a Leica, putting the focus area on exactly what I wanted to focus on and holding focus there; it's rarely failed.

So imho if you're a Contax user and want the 90, don't hesitate. Otoh if you're a Leica user just buy the Elmarit (or Summicron).

-- John Hicks (jhicks31@bellsouth.net), May 26, 2002.

Glenn. I don't recall Pop Photo ever testing the 90/2-APO-ASPH. Are you sure you're not thinking of the 100/2.8 Apo-Macro-Elmarit-R, which they tested and called the best short tele Macro lens ever tested.

-- Eliot (erosen@lij.edu), May 26, 2002.

the best one is the Canon 85mm f1.2 L

-- Mitchell Li (mitchli@pacbell.net), May 26, 2002.

I have to chuckle when reading John Hick's comments. I cannot tell you how many pictures I've seen where the 2 people standing side by side in the picture is out of focus and the the distant object between them is correctly focused.

I'll never be one to condemn auto everything cameras but it does dumb down its users to the point where all they do is frame the picture and expect it come out perfect.

-- Jim Wong (jkdub@hotmail.com), May 26, 2002.

Glenn T. wrote: "Pop Photo also tested the Leica 90 mm f 2.0 APO, and called it the best short telephoto they ever tested. Actually, the best short telephoto is the Nikkor AF-D 85 mm f 1.8."

I don't concur with these two statements. The January 2000 Pop Photo article referred to about the 90 AA states:

"SQF data indicate outstanding imaging performance, particularly notable for an f/2 medium tele.";

"Corner sharpness was acceptable from f/2 to f/2.8, very good at f/4 and excellent from f/5.6 to f/16. Optimum performance was at f/11";

"An outstanding f/2 lens-the best we've ever tested and far superior to the old 90 mm f/2 Summicron."

These statements clearly are meant to refer only to f/2 90 mm lenses and do not say the 90 AA outperformed the 90 f/2.8 Contax G or was the best short telephoto they ever tested.

I have used the 85 f/1.8 AF-D Nikkor over the past four years. I use mine quite often and I am always pleased with the results. This lens is excellent but to say it is the best short telephoto is an overstatement (unless one measures by cost) both in terms of wide open performance and bokeh which is judged by many as a bit harsh. I believe it is a (very small) notch below the modern Leica 90's, the 90 Sonnar G, or even the 85 mm f/1.4 AF-D Nikkor.

-- Doug from Tumwater (dbaker9128@aol.com), May 26, 2002.

Doug nailed several points I agree with completely (IMHO, of course!)

Here's how Photodo.com charted the 90 f/2.8s. And (BTW) the Leica 100 APO-Macro eats the lunch of either - it starts at 70% contrast in the center for 40 lppm - and then gets BETTER as it moves out towards the corners!! (9-12-15-18 etc.)

When Pop. Photo listed the Zeiss 90 as 'the best ever tested' the Leica APO 90 didn't yet exist - but on the other hand they've never retracted/updated that statement.

Erwin Puts ranks the 100 APO-R and 90 APO-M as neck and neck, though, which leads me to believe the APO 90 may trump the Zeiss.

Just for grins I also included the charts for the Zeiss 35 f/2 Planar and the pre-ASPH "King o' bokeh" Leica 35.

Can you say "Holy Doppelganger, Batman!"?

-- Andy Piper (apidens@denver.infi.net), May 26, 2002.

To whet your appetites until I can post some other shots:

This was made with the Contax 90 G @ f/4. Under the right- side arm of the cross in the center is a blur. In a full-rez scan that blur is a windchime, and you can not only see the 3 chime tubes, but also the threads holding them together.

The lens easily matched the resolution of my scanner (2700 lpi = 106 lpm).

-- Andy Piper (apidens@denver.infi.net), May 26, 2002.

Andy; good review and MTF charts......One comment; a 2700 scanner will only show 1/2 the 106 number you mentioned..A 85 line pair/mm negative readable with a microscope will only be readable as about 50 lines pairs/mm when scanned with a 2700 scanner.....I have used the canon FS 2710 for 2 1/2 years; the scanner system will only resolve a maximum of about 50 lines/mm with sharpest negative on earth...If the lens test chart is rotated say 45 degrees; the resolution will be ever less...Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 27, 2002.

Kelly - thanks.

Here are some more G images, including some with the 90:

Images

As to scanner resolution - the Nikon generates an image with 2700 pixels across 1 inch - or 106 pixels across 1 mm. If that doesn't equate to 100 lpmm, so be it. It still works as a standard for comparison, at least for me.

If a fine linear detail (e.g. a line in some text, since I don't shoot test charts per se) 'fits' into a space 1 pixel wide with no spillover into the adjacent pixels (consistently), I judge the lens/film combo to be resolving (making visible) at least 100 lines per mm (NOT line pairs!!)

Very few lenses get up to this level - my 90 'cron (nonAPO) almost always smears details at least 2 pixels wide, but even that resolution 'looks' sharp in a 8x12" print.

Not many lenses (important qualifier: that I've scanned from!!) meet the '1 pixel' test wide-open: the 90 APO, the 90 Elmarit-M, the 90 Tele-Elmarit (at the center) - and the 90 Sonnar-G.

The 90 Contax delivers sharpness/contrast that bumps up against the Elmarit-M in a package lighter than the thin Tele-Elmarit.

But note that I'm using Ms now, not Gs. Different issues.

-- Andy Piper (apidens@denver.infi.net), May 27, 2002.

Andy; All my lens tests were with the standard 1951 USAF charts...; mostly with Panatomic-X; with the exposures made by turning the the lamps on and off...(the 2 15 watt bulbs 45 degees to the charts ) the test booklets use the term lines per mm... What one reads on the charts are the group and pair last resolved there are 4 groups of 6 pairs; or 24 different sized patterns...The end result is what we call in optical engineering lines per mm....We know there are pairs because we all have spent many an hour reading the damn lines with a microscope! anyway the data are the same that the SPIE society uses; and all my Optical engineering text books; and also what Herbert Kepler used at Modern photography; and recently Popular Photography....

The sharpest 35mm negative I own is from our old Durst 5x7 camera with microfilm adapter..It had a 60mm Schnieder Componon; the lighting was with arc lamps; the film was 6556 Kodalith...At the best apertures the lens test reads either the Group 0 Pair 6 which is 89 lines/mm ; or an iffy group 1 pair which is 100 lines per mm... When this negative is scanned with the 2720 dpi scanner; only group 0 pair 1 can be read which is 50 lines per mm...I use the same lines per mm as most the rest of the world....I am not sure where this factor of two started.......I can scoot the super negative any way in the carrier and still only get 50 lines/mm max..

A 2700 dpi scanner can only resolve 50 lines/mm

A 4000 dpi scanner can only resolve 75 lines/mm

I rounded down the numbers; I started out and went thru school with a slide rule....And have worked as an Optical Mechanical Engineer...When I visted Santa Barbara Optical 20 years ago; Warren Smith was using the same definiton for resolution...

When I first got my 2700 dpi scanner 2 1/2 years ago ; I started to scan some negatives and slide for myself and customers...A nice sharp negative has alot more detail than the scanner can pickup....Maybe I will get a 400odpi scanner next year; If the economy holds out...

-- Kelly Flanigan (zorki3c@netscape.net), May 27, 2002.

-- Kelly Flanigan (zorki3c@netscape.net), May 27, 2002.

Kelly - good stuff. I wasn't trying to create discord.

At any rate, regardless of how many lpmm it resolves technically - my scanner will image things (eyelashes, hairs, fence wires, twigs, whatever) on the very close order of .01 mm wide on film (1 pixel wide @ 106 pixels-per-mm) - because I look at my full-res scans and see objects that are - 1 pixel wide and not more - on negs from good lenses.

The three 90 f/2.8s will create an image of fine detail as small as .01mm wide on the film (where other lenses do not) - i.e they all bump up against my scanner's limit before they run out of resolution.

From your notes it looks like that limit is 50 lpmm.

-- Andy Piper (apidens@denver.infi.net), May 27, 2002.

Thanks Andy;
BR>The kicker is that one pixel may or may not align to the sensor! and you see the ones that do!

regard Kelly

-- Kelly Flanigan (zorki3c@netscape.net), May 27, 2002.

Thinking it might be time for a little reality, I checked in with Photodo to see what they had to say on the subject. I consider their MTF grades to be a fairly accurate indication of how a lens will perform:

Elmar-M 50mm 1:2.8 = 3.9

Summicron-M 50mm = 4.6

Summilux-M 75mm = 4.5

Elmarit-M 90mm = 4.5

Summicron-M 90mm = 4.3

Elmarit-R 90mm = 4.6

Contax G 45mm = 4.7

Contax G 90mm = 4.4

Konica M 50mm = 4.5

Konica M 90mm = 3.8

Canon EF 85mm L = 4.6

Nikkor AF-D 85mm = 4

A couple of more interesting MTF numbers:

Summicron-M 35mm = 4.1

Summilux-M 35mm = 3.8

Summicron-R 35mm = 3.8 Contax G 35mm = 4.1

Nikkor AF-D 35mm = 3.9

-- Glenn Travis (leicaddict@hotmail.com), May 27, 2002.