90 apo vs 75 apo

[Csacwp]

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I shoot with 35mm and 50mm lenses about equally and currently have a 35 cron asph and a 50 apo in my bag along with the SL and M246. I shoot film on an M4. I'm looking to add a portrait lens to my arsenal. For a while I was lugging around an 80 R with me plus the adapters, but it took up too much space in my bag and was a pain to use on my M246. I got tired of swapping adapters on the SL and missing moments, so I sold that lens along with a 50 rigid cron and the adapters. I'm looking at the 75 apo and 90 apo and have read everything I can find on them, but I cannot figure out how they really differ in image quality. I also might consider a 75 lux as I did like my 80 R- the gentle rendering was great for photos of women. Whichever lens I choose would also double as a short tele for event photography, just to give me some reach over my 50 cron.

 

A final question: I've heard the 90 APO is hard to focus at f/2. Why couldn't I just do as Thorsten Overgaard does and fire off a few shots at once while slightly moving the focus ring, rather than slowly trying to focus. That way one photo is bound to be correctly focused and I can toss the others.

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[NB23]

And the question is?

[Csacwp]

Haha, I guess I rambled on a bit there.  The questions are:

 

In terms of image quality, rendering, bokeh- how does the 75 apo differ from the 90 apo?  I already know that it focuses closer, but it seems that the 90 can still get almost the same perspective given the extra 15mm.

 

The 75 lux is great for portraits since it renders gently, but why can I not just decrease the sharpening on photos taken with either of the APO Summicrons?  

[NB23]

a-ha, the classic "what should I eat and am I even hungry at all? Please help" question.

 

Maybe try the 28 cron, first?

[phongph]

Hi Csacwp!

I have got Sl 601, SL 24-90, M10, M35 Lux Fle, M50 Apo, M75 Lux.

I also have some concern as You before. For me, the very sharp len as Apo 50 is not suitable for portrait since my wife did not like at all. For my taste:

- Environment portrait: M35 Lux or M50 Lux,

- The portrait: the best is M75 Lux, other choice is M90 pre Apo (E55) or R80 Lux as yours,

Ps: I have not seen any focus problem of telephoto lens on SL601.

Have a good selection!

Thanks!

[fsprow]

I often use the 75 Aspheric Summicron and have been very happy with the results.

[adli]

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If you like the R80 look, buy the 75 lux or the 90 cron pre ASPH. If you like the look of the 50 Apo, buy the 75 cron. Pretty easy.

 

Focusing the 90 is not as difficult as some say, especially with the M10. The M10 is more precise than the M9 which was horrible to calibrate.

[Leicaiste]

Do you intend to use it on the M or on the SL ?

[adan]

Here's my experience:

 

The 75 APO-Summicron is the "sharper" lens at most distances - due to the floating element correction. The 90 APO is very good at long distances, but to my eye starts to get a bit "loose and sloppy" with fine details once closer than 10 feet/3 meters, since it does not have the floating element.

 

At least using them @ f/2.0. Stopped down is another story....

 

But against that - the floating element design of the 75 APO has caused me problems in about 50% of the samples I've tried since it came out 12 years ago. In that the focus doesn't always track the rangefinder perfectly at all distances (it does, after all, have an extra moving part in the lens to get out of adjustment). So it is a two-edged sword - great quality close-up when working, a real pain if even slightly out of adjustment (color fringes, poor focus).

 

And of course using the rangefinder - as opposed to live view/EVF - you can't see if the lens has "gone off the rails" until you look at the picture afterwards.

 

75mm, for me is "borderline" for portraits. Yes, you can get closer to get the same framing as a 90mm, but by getting closer, you get more distortion of noses and foreheads and such. I can get nice straight-on head-and-shoulders portraits with a 75 (at about 1 meter), but not closing in to get full-face at 0.7 meters. The 90 has a "kinder" perspective for the same framing.

 

The net result is, I have moved on (or backwards in time, depending) from the 75/90 APO lenses. Currently I use a 75 Summarit f/2.4 (with the same 0.7m close-focus limit, but no floating element, as the 75 Summicron). It is more reliable that the APO Summicron, and usually quite sharp (it may be biased for best IQ in the close range, like a macro lens).

 

"Backwards in time" - my own feeling is that older designs (75 Summilux, 90 Summicron pre-APO) make more sense as fast, short teles with a rangefinder. Because they have spherical aberration, which, while it reduces the maximum sharpness wide-open, spreads out the zone of "pretty darn sharp" over a greater depth, compensating a bit for any focusing error.

 

Explaining that with a picture, in the diagram linked below, while the "circle of least confusion" at full aperture is not as sharp a pinpoint as the APOs can produce, you get almost the same resolution anywhere in the diamond between the paraxial ray focus point and the marginal ray focus point. You get a "sharp" image from one set of rays, with a soft halo overlaid from the other set of rays. That is "leeway" for focusing with an RF @ f/2, that I find useful. Plus SA contributes to the "smooth bokeh" of those older lenses.

 

http://hyperphysics.phy-astr.gsu.edu/hbase/geoopt/imggo/sphaber.gif

 

That point becomes moot with TTL viewing/focusing, however.

 

Given I already have the 75 Summarit, the next time I see a pre-APO 90mm with 6-bit coding, I may snap it up. 75 for studio tabletops @ f/16, 90 with aberrations for portraits and general journalism @ f/2.0.

[onasj]

I've experimented with rotating the focus ring slightly while taking advantage of the M10's rapid continuous shooting mode.  It can help ensure that at least one image is moderately in focus, but decreases the likelihood of getting any photos in perfect focus.  For some shooters and situations, that may be fine; for others, you are better off just taking a few photos at the end of each of several attempts to get the focus right the standard way.  Practice makes perfect.  The medium-sized Lens Taab (a rubber focusing tab) can help with the 90 APO, though it adds a bit of bulk to an already bulky lens.

 

A better "trick" to getting a seres of shots at slightly different focuses is to simply shoot, lean in a bit, shoot, lean away a bit, and shoot.  With this technique, at least you aren't guaranteeing focus change while the shutter is open.

 

To be honest, the biggest aids to better 90 APO focusing for me were 1) patiently waiting for the rather stiff focusing ring to loosen through heavy use; and 2) good old fashioned practice.

 

Regarding your original question, my sense from the MTF curves is that the 90 APO is a bit sharper and less astigmatic than the 75 APO, but both are outstanding lenses.  Of course the substantially closer minimum focusing distance of the 75 means its reproduction ratio (1:7) is actually larger than that of the 90 (1:9).  In practice if you are shooting traditional portraits, the 1 m minimum focusing distance of the 90 APO is not a huge constraint.

[otto.f]

I often use the 75 Aspheric Summicron and have been very happy with the results.

I often use the APO 90 Summicron and have been very happy with the results.

 

That said, I often use the Summilux 75, but more on my Monochrome1 than on color M's, because my path has been that I made the best B&W images with it. My personal view is that this is the best M lens Leica ever made. But that's me, a lot of people struggle with its weight, bulkiness, stiff focusing (can be adjusted and is not particularly common with this lens). I think this speaks for itself:

http://lotwouda.zenfolio.com/p735541593

I learned here from somebody to put Auto Lens detection OFF, makes it much more original in the way it draws. I love its weight and have become used to it, I like to carry the body with it, as a grip and this works perfectly for me in streetphotography.

 

When you see the 75 as a sort of 50, I can only agree. A 90 is a tele, that's something else.

[Csacwp]

Thanks to Ken Hansen I was able to test drive a copy of the 90 apo this morning.  I had few problems focusing it by rangefinder at f/2.  Sometimes I took two or three photos and adjusted the focus slightly for each of them, and one of the three ended up dead on in focus.  I like the feel of the focus throw, and I think the bokeh is pretty nice- certainly a different character than that of the 50mm Summilux asph, which I hear is close to the 75 apo in look.  The longer MFD isn't a problem- you can still get in too close and have to step back a bit to get a good headshot with shoulders.  My only concern is that the lens is just so sharp.  This will be great when I use it for landscape, event photography, and photos where I want to capture some character and age in somebody's facial appearence, but for women it is very harsh.  When I edited the photo below, I reduced the sharpness in Capture One all the way and also reduced the clarity some.  The image was compressed by photobucket- it is far sharper and harsher when viewed on my monitor, and is very unflattering.  How would I go about smoothing out the skin in Capture?

 

http://s385.photobucket.com/user/csacwp/media/L1002504_zpsq4ejvqqj.jpg.html

 

[hoppyman]

Haha, I guess I rambled on a bit there.  The questions are:

 

In terms of image quality, rendering, bokeh- how does the 75 apo differ from the 90 apo?  I already know that it focuses closer, but it seems that the 90 can still get almost the same perspective given the extra 15mm.

 

The 75 lux is great for portraits since it renders gently, but why can I not just decrease the sharpening on photos taken with either of the APO Summicrons?  

I bet that you wouldn't notice any difference. For the rest it really depends which characteristics are most important to you personally. For me the APO Summicron M 75 ASPH is one of my favourite M lenses. It's significantly smaller to use and carry too (than that 90)

 

On your second question..... Yep! Personally I much prefer to start with the sharpness and micro contrast from the modern designs. Certainly the Summilux M 75 can give you a gentler rendering and is very popular for women's portraiture and the faster aperture of course.

[otho]

In short words: both are great lenses. My 75 cron & 90 APO cron are often paired in travel with 35 cron.

[Csacwp]

In reviews of the 90 apo I often hear people complain about the up-close performance of the lens wide-open, saying that it is sharper at longer distances. I am confused about this- on a portrait lens, isn't it desirable for the lens to be a little softer wide-open and used at near distances?

[SilentShutter]

People complain at a high standard - like always with Leica. 

[anickpick]

In reviews of the 90 apo I often hear people complain about the up-close performance of the lens wide-open, saying that it is sharper at longer distances. I am confused about this- on a portrait lens, isn't it desirable for the lens to be a little softer wide-open and used at near distances?

 

Unfortunately, the close up performance (at f2 / up to at least 2 meters) of the 90 apo summicron is not great at all.

In this regard, the 90 apo is bested by all other current M lenses.

 

Even for a portrait, personally I prefer a modern lens with good close up performance wide open.

The wrinkles and lines give our faces character. Yes, that's true for women too.

[otho]

Additionally, both cron 75&90 Apo lenses are superb in Sony A7x body series, even without Kolari Mod sensor.

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Hallo,

Look here: Leica M

[Peter H]

I prefer the 90mm 2.8 Elmarit M to the 90mm Summicron. It is capable of beautiful images, is very versatile and reliable,  and is the easiest lens to use and focus accurately in the entire over-50mm Leicas M lens range, in my experience.

 

But it doesn't answer your particular question about the two Summicrons. I just want to point out that the most expensive lenses aren't always the best.

 

For what it's worth, I prefer the 75mm Summicron to the 90mm Summicron (which I no longer own) because of its closer focussing and its ultimate sharpness, but these are very small considerations when comparing at such a high level. I also prefer its size. Smaller lenses always start with an advantage as far as I'm concerned. 

[Csacwp]

Anickpick, what else do you not like about the close performance of the 90, and do you find the 75 cron to be better in that regard?