Question regarding 75mm summilux sharpness wide-open

[A miller]

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Is this lens supposed to be tack sharp wide open (f/1.4) at the precise point of focus? Or, is it normal to be just reasonably sharp (particularly in comparison to the OOF areas)?

 

I'm trying to figure out whether the lens I have needs to be adjusted.

 

Many thanks in advance for any thoughts.

 

Best,

Adam

[swamiji]

Tack sharp at f/1.4, No. Wide open it's quite soft, which in my view is what I want. You need to stop it down a bit to get tack sharp.

 

You can purposefully back or front focus, to test it's calibration if you are concerned. (Assuming you are using a body other than a M240)

[A miller]

Thanks very much. The sharpness that I am getting at reasonably close range and completely wide open is about the same degree of sharpness that I would get through zone focusing a modern 35mm lux fle on a sunny day (with the subject well within the focus zone). I am just curious whether I should be getting sharper results at this 1.4 aperture. Thanks again.

[MarkP]

You can test this yourself by making a number of small forward and backward focusing adjustments about what the rangefinder tells you is the optimum focus, perhaps against a focusing chart or at an angle to a ruler. Obviously on a tripod and with cable release to be obsessive.

 

This lens is pretty good wide open. There is also a slight drop in contrast when wide open (as for many lenses) - just make sure you aren't confusing this with sharpness.

[adan]

You should be able to get sharpness about like this with the 75 @ f/1.4.

 

But there is virtually zero leeway to miss focus, and the longitudinal chromatic aberration (green and cyan glows along the nose and in the eyelashes) will be present.

 

Additionally, the sharpness perception will vary with the type of picture - contrasted against a blurred background like this, the focused sharpness looks darn good, but for a landscape, or five guys lined up against a wall, it may look just adequate (if that).

 

M9, 100% crop plus full frame view (taken just today at the Denver Shakespeare Festival - Happy 450th, Bard!)

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[Paul J]

As usual Adan as pretty much said it all! That's a good example of sharpness too.

 

I think the lens is sharp wide open. Not by modern standards but still sharp.

 

Up close, 1m or less, it appears softer wide open but still quite sharp none the less and certainly sharp enough. Viewed at native sizes it looks very sharp. At 100% you see good linear sharpness but the finer detail is more restrained in the glow and it really depends on the texture of what you are shooting and the light you are shooting in. But this is the same for most fast lenses.

 

At medium distances I have found it is really sharp wide open. But as a comparison my modern lenses like the 35 Summilux FLE is razor or tack sharp wide open, so it's certainly a notch under that.

 

Mine was soft until it was adjusted and repaired. There was a broken part. Any older lens needs a CLA. It came back a new lens and went from sort of acceptable and unreliable to very good.

 

Stopped down it is probably one of the sharpest I own of any system.

[Gerard]

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Here's a shot at f1.4. It gives a good idea (in my mind at least) of what the 75 lux delivers. Soft on skin tones, arty on bokeh, sharp where you need it.

 

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But it is worth having the lens cla'd; it is one of the lenses on the edge of the rangefinder's capability. If slightly out of whack; it will disappoint. It should not cost more than £200 for a full service.

[pico]

Andy Piper, you are the man!

Thanks for that!

[A miller]

Sincere thanks to everyone for their input. You have put many nails in the coffin of the conclusion that the lens I just purchased has a focus shift issue. I did some tests and concluded that I had to turn the focus ring slightly more to the left of what the focus patch was telling me was spot on focus to get tack sharp results.

 

I will take the lens to Leica in NJ one morning this week myself and see how much it will cost to make the necessary adjustments.

 

I really appreciated seeing the sample images that some of you posted. They are fabulous.

 

Thanks again,

 

Adam

[MarkP]

Glad you've sorted it out Adam but why don't you get it 6-bit coded?

The focus adjustment is then checked and optimised regardless as part of the work after the new flange is fitted.

[A miller]

Good question, Mark, and thanks for mentioning it. Since the MM and M9 have a manual setting for this lens, I haven't thought of it as super critical to have done. But I was planning to ask Leica about the incremental cost of doing this over and above having the focus adjusted. If it aint that much, I'll probably go for it. Thanks again and all the best, Adam

[gpwhite]

Good question, Mark, and thanks for mentioning it. Since the MM and M9 have a manual setting for this lens, I haven't thought of it as super critical to have done. But I was planning to ask Leica about the incremental cost of doing this over and above having the focus adjusted. If it aint that much, I'll probably go for it. Thanks again and all the best, Adam

 

6-bit lens flange was $125 the last time I had it done but I imagine it costs more now. Well worth it, as you no longer need to remember to fiddle with the User Profile adjustment for either either M or M9.

 

As a couple of posts above seem to suggest, exposure is also a bit more variable than expected with 75 f/1.4 @ wide open (or 80 f/1.4, 50 f/0.95 for that matter). I find the M exposure meter is often +0.5 EV, meaning that to save the best, crispy highlights in the tiny, centralized spot of focus @ f/1.4, it is good to increase shutter speed 1/2-stop beyond what the meter suggests.

[A miller]

Thanks for tips, GP. Much appreciated.

[JeffWright]

6-bit lens flange was $125 the last time I had it done but I imagine it costs more now. Well worth it, as you no longer need to remember to fiddle with the User Profile adjustment for either either M or M9.

 

As a couple of posts above seem to suggest, exposure is also a bit more variable than expected with 75 f/1.4 @ wide open (or 80 f/1.4, 50 f/0.95 for that matter). I find the M exposure meter is often +0.5 EV, meaning that to save the best, crispy highlights in the tiny, centralized spot of focus @ f/1.4, it is good to increase shutter speed 1/2-stop beyond what the meter suggests.

 

Leica NJ now (as of late 2013 anyway) charges $340 for the 6 bit flange. Leica did a focus check and CLA of the lenses I sent to them. DAG does it for considerably less, considerably faster, and seems to do just as good a job.

 

The 75 'lux will challenge your body's rangefinder calibration. My first evaluation of the M240 was a rental camera in which the rangefinder was OK just a bit off. A bit off on the Summilux gets you all out of focus images.

 

The lens does have focus shift as you stop down, that is unavoidable. Buy a ND filter, get the rangefinder & lens calibrated, and use the lens between f/1.4 and f/2, and life will be fine.

[lpeeples]

Sorry to hijack this thread but a basic question. If I have a backfocus issue with one of my lenses, I am assuming its the lens that needs adjusting and not the body. If I sent it in to Leica, does that mean a trip to Germany and long wait or is a focus adjustment done here in the US and faster?

[Gerard]

If you can, I'd send in the body with all lenses. As if the rangefinder should be out, and then adjusted, you may find the lenses you feel are currently okay start showing issues. At least if you send the lot you can be sure all are adjusted to within tolerance within one hit.

[phongph]

Here's a shot at f1.4. It gives a good idea (in my mind at least) of what the 75 lux delivers. Soft on skin tones, arty on bokeh, sharp where you need it.https://www.flickr.com/photos/dedrot/11218641634/sizes/o/But it is worth having the lens cla'd; it is one of the lenses on the edge of the ran

gefinder's capability. If slightly out of whack; it will disappoint. It should not cost more than £200 for a full service.

Hi Gerard!

It is a good len for portrait!

Have a nice day!

Thanks!

[uhoh7]

What the 75 Lux can do wide open. I have an older copy, but it only had about 300 shots since new- was able to trace the provenance from mid 80s. Calibration is perfect. Condition LN.

 

Mammoth Man by unoh7, on Flickr

 

cet moi by unoh7, on Flickr

 

Mini in Snow by unoh7, on Flickr

[uhoh7]

Let's compare F/1.4 to 5.6

 

L1026621 by unoh7, on Flickr

 

White House by unoh7, on Flickr

 

These are all full size on flickr so you can take a very close look if desired.

 

At 1.4 it's "Glowy" some sort of color aberrations, somebody can remind us exactly what (Adan notes it too, I see. By F/2 it's basically searing, and arguably too sharp for portraits. F/4 it's ridiculous. And at 5.6 it is the equal of the 90AA.

 

Of course 1.4 is only usable for a portrait like my second one up there, unless you like fuzzy noses. For portraits a Nikkor LTM 85/2 is alot sweeter than the Lux, or the pre-asph 90 cron is better too. This is why Put's at first said, "well if you need it, you need it". Later he became more affectionate to the lens.

 

OOF is very nice, that's for sure

 

In very bright conditions WO seems softer. Above, it's "cooking". Soft? Do they look soft?

 

Erwin:

"At full aperture the lens exhibits a medium to high overall contrast, with extremely fine details quite visibly recorded. Very fine details are clearly resolved with some softness at the edges. Some astigmatism is visible in the outer zones, which softens the finest possible textural details. This performance holds over most of the image field, with a detectable reduction in the outermost zone. The corners, although much softer, still record very fine details with good visibility."

 

In the context of such a fast speed, that does not describe a soft lens, nor do my samples show one---IMHO

 

Puts on F/2:

"Stopping down to f/2.0 achieves the high overall contrast needed to record extremely fine details with clarity and crispness. Higher contrast generally gives the fine details more clarity and sharper edges. The outer zones now also improve and only the extreme corners lag a bit beyond this performance."

 

You certainly see this striking difference, at f/2. That is true with many many great lenses. In fact which is the lens that does not get alot better 1.4 to F/2?

 

By 2.8 the 75 Lux can compete with anything:

"At f/2.8 the contrast is slightly higher yet and now the micro contrast is at its top, allowing the clear and crisp rendition of exceedingly small details. Now a tripod is most needed to record the finest possible details. We are talking about small details with a diameter of about 0.3mm in the image, photographed at a distance of 7.5 meters! You need to view the real object at really close distances to see what the lens/film combination can record. This performance level is maintained from f/2 and f/2.8 to f/8 and the choice of aperture needs only to be justified on depth-of-field arguments."

 

I believe at f/4 it beats the 75 APO, from there on down. At F/2 the APO is better for sure. There are many beat up copies and used 75/1.4s are notorious for calibration issues. Stories of trying 3 or 4 and all are off, are not unusual. CLA is not for the faint of heart. It's glued together. I would not let anyone touch mine, outside DAG. Even then I cringe at the risk.

 

75 Luxy by unoh7, on Flickr

 

The price of such performance: it's a monster.

The M9 is so bad over ISO 800, I have to have it. But the APO is much more practical and alot cheaper. For M10 it would be smarter. I have a 75 Summarit which is what I actually carry in daylight when I want a 75.

 

Oh! by unoh7, 75 Summarit.

 

Summarit has richer colors, like most of the post Y2K lenses. But it does purple fringe, and the Lux is sharper on the edge, without a doubt. I was completely ignorant of how strong the 75 Lux really is when I bought it, I find it hard sometimes.

 

Sign of Aggression by unoh7, 75 Lux WO M9

 

Color signature very similar to 50 cron v4, 135/2.8 and TE 90 thin of same general era. Very true to reality, unlike the rich Karbe lenses.

 

Some people think you want EVF for a shot like that. I have news: if calibration is good, or you know to compensate, no EVF can equal RF for accuracy in very thin DOF. Shooting A7.mod beside M9 for years now, M9 always wins.

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Hallo,

Look here: Leica M

[tsleica]

I think the 75 lux is my fave lens in the Leica M stable..too bad its so expensive..

I shoulda bought one mint back in the day...oh well..my noct f1 will have to do..