More on the Hexar/M/Voigtlander test on Nemeng!

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I have just done a few calculations based on the focusing mechanics of my 50/2 Summicron. They claim a difference of .4mm between the M3 and the Hexar ( not to mention the larger difference between the Voigtlander and M of .59mm which no one has mentioned) In order to move the lens in relation to the film by this amount ( ie change focus if you were using an SLR or a ground screen at the film plane) the lens focusing barrel has to be rotated by just over 7mm of it's circumference -thats the difference between the infinity mark and a point between the 5 and 10 m setting!!!!!! In conclusion there is no way this is not going to show up on film -even stopped well down you will see it. OR ............... - they have got the measurements wrong!!! - these measurements, on examination, are so outside far out that they are in the catogory of total incompatibility -and that includes the Voigtlander! I cant believe that even the most casual user would not pick up these errors if the measurements are correct. I have to conclude from looking at the figures as published that their measurements are wrong! This is by no means a conclusive answer to the compatibility question!

-- Johann Fuller (johannfuller@hotmail.com), May 18, 2002

Answers

Correction to the above....... it's worse ( got my figures an columns in a twist) it's at best an error of .75mm more than the flange to outer rail M spec ( and it's not clear what he tried to measure) - Put in simple terms; on my body and lens ( measured to within leica tollerances for the both flange to rail distances) you would have to set the lens on the scale at between 3 and 5m to duplicate the distance from the film that the measured hexar would focus the lens at infinity - way - way out!

-- Johann Fuller (johannfuller@hotmail.com), May 18, 2002.

Look - I agree. I personally think the Hexar RF "back-focus problem" is more in people's heads than with the camera bodies. IMO the LTF differences are purely attributable to the way people measure it.

-- Andrew Nemeth (azn@nemeng.com), May 18, 2002.

what does this have to do with photography??

-- grant (lotusphotography@yahoo.com), May 18, 2002.

Well, gee Grant, some of us use cameras to take photos. Others I guess merely contend themselves with making copies of what they see at MOMA.

-- Andrew Nemeth (azn@nemeng.com), May 18, 2002.

Why guess buy a Leica body play safe and be happy.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.


johann -- i may be doing something wrong here, but with my summicron 50 mm, rotating the focus ring from infiniting to 5 meters displaces the rear element by VASTLY!!!! more than .4mm. i think the actual number may be 10 ten times that or about 3-4mm. please check your methodology. although the slope of the helical varies, it appears to take only a slight focus ring shift to achieve a .4 mm change. others should duplicate this simple test.

-- roger michel (michel@tcn.org), May 18, 2002.

Allen,

I suggest you constitute a foundation to help us, poor Hexar owners to get the difference in price...

Stop reading biased tests! TRY YOURSELF like I did before buying mine.

Friendly

François P. WEILL

-- François P. WEILL (frpawe@wanadoo.fr), May 18, 2002.


to put this in perspective, i think the actual back-focus error is roughly in the same range as the focus shift error between f1 and f5.6 (or 8) that erwin puts reported in his thorough review of the noctilux. i got a lot of use out of the rf, including using the camera with the 75 lux. the pics seemed fine. my real prob with the rf is shutter lag -- that's why i sold mine. i just couldn't stand the way it waited to fire. and before you complain that 1/10th of a second (100 miliseconds) isn't a long time -- PLEASE TRY THE CAMERA YOURSELF after becoming accustomed to an M. and p.s. why does puts report a 10 milisecond release time for the m7, but others have cited leica figs that place it at around 30??? for what it's worth, the 7 seems exactly the same as the 6 in this regard to me.

-- roger michel (michel@tcn.org), May 18, 2002.

suggest you constitute a foundation to help us, poor Hexar owners to get the difference in price

Francios you did say you had to take your Hexar to a repair shop to get it adjusted.A lot of folks on this Forum have not been to happy with the Hexar.Truth is in small enlargements you would not really see the fall of in quality go big and well.Why should anyone take a chance when it is just a question of waiting and saving.Think about the Leica also holding its value.In the medium to long term by going the Leica route you could end up also saving money.I have thought long and hard on this and read everything as i need a second body and i want it now having little patience.I have decided on waiting as the sensible decission,why gamble.Guess what at the end of my wait i will have another Leica all good things are worth waiting for thats what my gran used to say. Regards Allen

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.


François

I already have M6 so i am not desperate.I like one camera with B&W and one with colour.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.



Allen: >> Francios you did say you had to take your Hexar to a repair shop to get it adjusted <<

Sorry Allen,

I NEVER said my Hexar RF had to be fixed in a shop... It was perfect straight out of the box.

I said IF a rangefinder misalignement surfaces it would be fixed by any good shop... And by the way at no cost under the guarantee.

The only rangefinder camera which failed in my hands was my old M5 and I can forgive it to have done so it was an old soldier and just fade away...

I don't care about the alleged investment in the long term represented by a M body, first an foremost because like the proverbial boots which are made for walking, my camera has to take pictures. And the result for me is what you get on actuel pictures.

I remember too well when in difficult circumstances, I was obliged to sell my M4-P how much it was depreciated by the simple fact it has some dents (unavoidable in an everyday professional use)despite the fact it was 100% OK for a user. So goes for me the Leica M as a long term investment...

Finally, I don't think this over-estimation of a Leica body will really survive very long, as I don't think the silver based film will survive as long as the M has already survived.

I didn't buy my Hexar RF before testing it during a full week (that were my conditions with my retailer)... When I realized all the alleged problems of focusing were just bullshits and misalignements probavly linked to a few early batches (some M rangefinder ARE misaligned on new cameras) I bought it.

Since this it is doing fine...

What you seem not to understand is that the alleged problems on back focusing are just tales and everybody having actually used an Hexar RF with a properly set rangefinder NEVER ACTUALLY EXPERIENCED any problem... Unless they WANTED to have a problem... I have absolutely NO CONFIDENCE in Popular Photography "test" ... I think this is pure intoxication...

JUST TRY IT YOURSELF...

You can buy a mighty fine Leica lens with the difference in price between an M6 TTL of a M7 THINK about that, a test will costs you NOTHING.

Friendly

François P. WEILL

PS: remember also that there's a constant rule well known by people in charge of reader's corner in any publication: dissatisfied people will be more prone to complaint than satisfied people to express their satisfaction ... So it is quite normal you get more posts on problems with an Hexar RF than otherwise...

-- François P. WEILL (frpawe@wanadoo.fr), May 18, 2002.


Francois, one of Allen's techniques is deliberate mis-statement of "what someone said on a prior thread." He's done it to me, he's done it to you. He also magically "knew" how I took a photo I posted on another thread (the Zapotec girl in Oaxaca) and when I showed how the shot was taken, he didn't even acknowledge the absurdity.

-- Jeff Spirer (jeff@spirer.com), May 18, 2002.

said IF a rangefinder misalignement surfaces it would be fixed by any good shop... And by the way at no cost under the guarantee.

The only rangefinder camera which failed in my hands was my old M5 and I can forgive it to have done so it was an old soldier and just fade away...

I don't care about the alleged investment in the long term represented by a M body, first an foremost because like the proverbial boots which are made for walking, my camera has to take pictures. And the result for me is what you get on actuel pictures.

I remember too well when in difficult circumstances, I was obliged to sell my M4-P how much it was depreciated by the simple fact it has some dents (unavoidable in an everyday professional use)despite the fact it was 100% OK for a user. So goes for me the Leica M as a long term investment...

Finally, I don't think this over-estimation of a Leica body will really survive very long, as I don't think the silver based film will survive as long as the M has already survived.

I didn't buy my Hexar RF before testing it during a full week (that were my conditions with my retailer)... When I realized all the alleged problems of focusing were just bullshits and misalignements probavly linked to a few early batches (some M rangefinder ARE misaligned on new cameras) I bought it.

Since this it is doing fine...

What you seem not to understand is that the alleged problems on back focusing are just tales and everybody having actually used an Hexar RF with a properly set rangefinder NEVER ACTUALLY EXPERIENCED any problem... Unless they WANTED to have a problem... I have absolutely NO CONFIDENCE in Popular Photography "test" ... I think this is pure intoxication...

JUST TRY IT YOURSELF...

You can buy a mighty fine Leica lens with the difference in price between an M6 TTL of a M7 THINK about that, a test will costs you NOTHING.

Friendly

François P. WEILL

1.said IF a rangefinder misalignement surfaces it would be fixed by any good shop

It surfaced on yours who wants the bother.

I don't care about the alleged investment in the long term represented by a M body,

2.Short and medium you can get Hexars for little money,indeed they are a redundant brand the Copany has lost interest.

don't think the silver based film will survive as long as the M has already survived.

3.When photography surfaced many people thought it was the end of paint and canvas.

I didn't buy my Hexar RF before testing it during a full week

4.Did you compare large enlargements of course no.You do not make large enlargements be happy,should have bought Nikon.

5.A good few respected resources say that you will get a drop in quality if you mix and match ,unless you go large you will never know.I would.Bottom line, yes real bottom line,no comment by Hexar...that tells all.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.


Allen,

I hate to start a flame but I equally hate to be confronted with unfairness

You write: >> It surfaced on yours who wants the bother. <<

You probably know better than I do what happened to my Hexar RF or you simply deliberately LIED...

ANYBODY knows perfectly a good shop will fix a rangefinder misalignement... If it occurs... On an Hexar as on a M...

>> Short and medium you can get Hexars for little money,indeed they are a redundant brand the Copany has lost interest. <<

They have lost so much interest as they have recently issued an entirely new multi focal lens Dual 21 - 35 mm (see their Japanese site). Again a bullshit carried here and there you make yours...

>> 3.When photography surfaced many people thought it was the end of paint and canvas. <<

Photography will survive as Photography when all Photography will be digital like Photography had survived the evolution from wet collodion to dry plates and then from dry glass plate to film... This is sheer non-sense... Ever tried to get some fresh material to obtain wet collodion or glass plates for a wooden view camera of 19th century vintage ? And then it is much more likely you'll be able to manufacture glass plates yourself in a darkroom (Orthocromatic plates of course) than to manufacture yourself 35 mm rolls when nobody will produce them anymore... Your remark is both irrelevant and technically unsound.

>> 4.Did you compare large enlargements of course no.You do not make large enlargements be happy,should have bought Nikon. <<

I think 30 x 40 cm is large enough for a 35 mm negative to reveal any loss in quality... Greater enlargment will reveal absolutely nothing as the grain will begin to show and the distance it might be observed will be such as any defect will be masked by the lack of separtiing power of human eyes... But I assume you know better than me the dimension I made my negatives blown to test my Hexar RF...

>> A good few respected resources say that you will get a drop in quality if you mix and match ,unless you go large you will never know.I would.Bottom line, yes real bottom line,no comment by Hexar...that tells all. <<

That tells NOTHING at all... And you have the perfect demonstration of the irrelevance of their measurement by Johann Fuller in this very thread... Not a single of these "respected sources" ever proceeded with the slightest kind of scientific rigor. This is sufficient for me to discredit their allegations.

Not to mention the question of the manufacturing tolerances of the LTM to M converting rings and dilatation and contraction issue I submitted to the forum in a previous thread.

Now you can save the money for a Leica M if you want, nobody can force you to use another solution if you don't want but stop using false quotations and interpretations to justify your position. Your old position about wanting an all mechanical - manual camera was much more convincing and honnest.

François P. WEILL

-- François P. WEILL (frpawe@wanadoo.fr), May 18, 2002.


bullshit

Wow! Francios even going for those words.The truth always brings out anger.Many people on this Forum have had a problem with the Hexar this is a simple fact.There have been a good number of reports by generally reliable sources again a simple fact.You own a Hexar which tends to make people bias again simple fact.When i bought my new Lieca M6 i did not take it to a repair shop to have it adjusted fact. The Hexar will not be worth as much as the Leica in 10 years fact.The Hexar has been reported with shutter lag not the M fact.The M is a lot better build fact.The M as a object of craftmanship is more enyoyable to use fact.Lense compat is not a thought fact.Difference in price between a new Hexar and M6 Mint-£150 fact.Francios wish he had a Leica body instead of another J body fact(you know that is true) I love full mechanical fact.Leica photographers are the best maybe true and Francios a gentleman mostly true.Regard Allen

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.



And nobody else in the world has ever got me to write as much fact.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.

100 years war !

-- Richard Brown (rubyvalentine@earthlink.net), May 18, 2002.

Well, here's an interesting data point. I did an infinity-focus test with a wide angle lens. I used a 28mm Summicron at f/2.0, focussed at infinity. The film was Ilford Delta 100 exposed at EI 50. I first put the Hexar on the tripod, mounted the lens, set it to the infinity stop and made a series of exposures. I then took the film out of the Hexar, loaded it into an M6 .58, switched the lens, mounted that rig on the tripod and shot another series. The exposure was 1/500 at 2.0. I souped it in Rodinal 1:50. I picked a central neg from each series to avoid problems with film curl, and scanned it on an LS-4000 at 4000 dpi. I adjusted levels in Photoshop, and cropped the section out of each image. The sections were sharpened (100%, 1, 0) and converted to jpegs in Photoshop.

The results are mildly interesting. While there's no evidence of a 1 mm (or even .4 mm) difference in focal plane, there is a sharpness difference in the images. Not enough to worry about - especially if the camera were hand-held - but it's there. Comments?


The whole scene (enarged area marked in white)


The image from the Hexar


The image from the Leica



-- Paul Chefurka (paul@chefurka.com), May 18, 2002.

And that is clear on a low res computer screen fact.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.

even though everybody seems to be having so much fun, just to drag this ack to the orig topic, i must reiterate that i think johann mite have made a mistake in his measurements. anyone can repeat this simple test (and at least get a rough approx of the results). to move the rear element .4mm requires only a small movement of the helical. moving the focus ring from inf to 5m on the cron 50 moves the helical several mm!! not .4. as for the above res test, you really need to repeat the shot five to ten times, refocusing each time. the rf has a margin of error on both cameras (a little more with the hexar because the effective base length is slightly shorter).

-- roger michel (michel@tcn.org), May 18, 2002.

About the need to refocus in my test - that was not required. The lens was focussed hard against the infinity stop, providing an absolute register. The position of the lens unit in the helical was absolutely the same in both sequences.

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.

i meant to add that in the above comparison fotos the exposure is very different in the two shots (either at the neg end, print end or both). exposure must be identical to even begin to compare resolution using prints.

-- roger michel (michel@tcn.org), May 18, 2002.

IMO it doesn't matter in this case. The resolution is different enough to be obvious - even jpegged on a computer screen. The difference is even more striking in the original tifs.

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.

sorry paul -- i did not realize that the shots were at inf. that was a good idea. what about the apparent exposure diffs?? is that just a scanning issue (although i'm not sure if that makes it irrelevant)?? perhaps there is no way to equalize exposures because even if you set the hexar to manual, there is no way to know the true speeds of either camera (especially the mechanical one).

-- roger michel (michel@tcn.org), May 18, 2002.

Paul. Perhaps it's my eyesight (which is problemmatic) or computer screen, but I can't see much difference in the two enlargements. Could you elaborate on the differences you saw originally?

-- Eliot (erosen@lij.edu), May 18, 2002.

The Hexar was set to manual. There's no way shutter speed differences would give the effect you see here - that was me screwing around with levels in Photoshop. I'm of the opinion that even if I got perfectly matched images, you'd still see this difference. It's too big to be a contrast artifact.

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.

paul -- perhaps you are an old hand at this, but i can tell you from bitter experience that even small differences in neg density (say +/- one half stop or more) and similar small differences in print density (if that is the rite word to use in the context of a print) make for big differences in resolution. many carefully planned lens tests have been ruined by cameras that were firing at 750 when set to 1000 or by small differences i dev regimen. at a min, you have to use the same roll of film (maybe you did). also, outdoors, lite can change very quickly. the scanned images show very different contrast and density. in these circs, it cannot be a fair comparison. i know from experience that this degree of difference can affect res. p.s. i am no hexar booster -- i sold mine because i couldn't stand the shutter lag.

-- roger michel (michel@tcn.org), May 18, 2002.

On my monitor, viewing the images on this page, the lettering on the real estate sign is more legible in the Leica shot and the legs on the sign are better defined. There's a small loop of foliage above and to the left of the sign, at the top of the dark space between ther two tree trunks - in the Leica shot the stem within the loop is visible, in the hexar shot it's not.

Pretty small potatoes, really, given that this is an actual pixels enlargement of a 4000 dpi scan.

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.


Roger, these were shot on the same roll of film, and the roll was developed uncut. The light didn't change at all during the exposures - we had heavy even overcast here all day. I understand what you're saying about small differences, but I scanned three negs of each series, and they all show the same differences, even before any Photoshop manipulation was applied. I'm utterly confident of these results.

The obvious caveat is that this is still just one one test on one Hexar, one Leica and one lens. Still...

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.


i guess the bottom line is that BOTH shots show pretty amazing resolution for such a tiny pic section. in my view, the results from the hexar indicate that, for your camera at least, there is absolutely no compatability prob.

-- roger michel (michel@tcn.org), May 18, 2002.

Paul. Perhaps it's my eyesight (which is problemmatic) or computer screen, but I can't see much difference in the two enlargements

Your eyesight must be a prob seems pretty clear to me.

-- Allen Herbert (allen1@btinternet.com), May 18, 2002.


paul -- thanks for having the patience to answer my sincere questions. such civility is a rare thing around here these days. it sounds like your methodology was sound and i accept your results. as i said before, i think your hexar acquitted itself quite well. i don't think FFD is ever going to be a limiting factor for you. happy snappin'!!

-- roger michel (michel@tcn.org), May 18, 2002.

one last thing: there are certainly other things besides FFD specs that could have affected the image quality here -- film flatness and pressure plate position chief among them. the two cameras have very different methods of assuring flat film. also, the stress of motorwinding can affect flatness. these points were taken up recently in an interesting piece posted on the german zeiss site. as for pressure plate position, that is a major prob for most cameras. it is very hard to design and then manufacture a spring loaded plate that is in the rite place whe it leaves the factory AND stays that way. it would be interesting to compare three leicas against three hexars -- both to know how the two brands stack up AND to see how good the leica design (and QC) is. got some spare time paul . . . . :)

-- roger michel (michel@tcn.org), May 18, 2002.

The issue of the pressure plate was just raised in a private correspondance. I did take pains to make sure this factor was mitigated - I waited about a second between exposures on the Hexar to let the geometry settle down, but didn't wait too long to avoid film curl due to "memory" in the film base.

However, the amount of difference I see here is much more likely to come from factors like pressure plates than differences in FFD.

I agree that the resolution is pretty good. When you consider that the image was shot with a 28mm wide open at f/2.0, and the enlargement is a 100x200 pixel section of a 4000 x 6000 pixel original, I think that both cameras acquitted themselves admirably. On my screen, the original image (enlarged to the size of the blown- up sections) is 36 x 54 inches. Not too shabby at all.

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.


Roger - sure I've got spare time. Got two more Hexars you can send me?

-- Paul Chefurka (paul@chefurka.com), May 18, 2002.

Paul, the Hexar image looks grainier and has less edge sharpness than the Leica image. It does not appear out of focus, which it would if there were a register distance discrepancy. It looks more like a difference in application of unsharp mask (I know you said they were the same) or data loss from compression or file format (you did mention they were jpegs).

-- Jay (infinitydt@aol.com), May 18, 2002.

OK; In the next test here we place the Noctilux on the Hexar; and shoot the same shot way stopped down to F2.0 ..(This is breaking the sacred Noctilux law; but necessary for testing purposes...).Do not try stopping a Noctilux down by yourself; send it to a Leica technician..Notice how the stopped down image focus shift of the Noctilux makes the Noctilux test shot the best of the three tests. The Hexars are all aligned at the factory for the Noctilux..Erwin and Herbert are keeping this a secret..

-- Kelly Flanigan (zorki3c@netscape.net), May 18, 2002.

Paul - Nice test.

..but check a couple of things for me.

Could you take a look at the distant trees in both negs, and also something CLOSER than the sign (say the grass or cement cracks leading towards the camera?

If the Hexar was misfocusing, presumably it was CORRECTLY focusing somewhere else (i.e the wrong place), in which case those parts of the negs should be SHARPER with the Hexar and SOFTER with the Leica.

Also, the sign appears to be 50-80 feet away, which seems too close for an infinity-focus test at f/2, even with a 28. Not a criticism of your testing, but if, for example the distant trees are sharp with the Hexar while the sign is sharp with the Leica, then it seems like it's the LEICA that's out of whack, focused at infinity.

On the other hand, if the Hexar image is just - softer - everywhere, then I don't think we're seeing a focus difference. There would have to be some other factor involved - although I can't imagine what.

-- Andy Piper (apidens@denver.infi.net), May 19, 2002.


Since you get a free Noctilux, what's the price of the house? Might be a bargin.....

And who is Francios??

I thought the gentleman's name was François....

FWB

-- F, William Baker (atelfwb@aol.com), May 19, 2002.


I have just one question about all this: assuming that Konica employs competent engineers, why did they manufacture a camera with the M mount if the lens compatibility issue really exists? I would tend to believe that the difference (as illustrated by the enlargements on this thread) could be seen by using different bodies, whether Konica or Leica, as well. And no doubt using different samples of the same lens on either body would also show up some differences at this level of enlargement. The pictures shown really highlight the fact that it's a non-issue, at least for any conceivable practical purpose.

-- rob (rob@robertappleby.com), May 19, 2002.

Now that Paul has pointed them out, I can see the differences. I think the main point is that there are small differences between the Hexar-RF and Leica-M, which may not show up in actual use. That is, unless the camera is placed on a tripod, focussed critically, used with high resolution film, and the picture is enlarged sufficiently.

For me, these differences are trivial and unimportant. I just never liked the handling of the Hexar-RF, including the shutter noise and shutter delay, which is perceptible with the Hexar but not with M.

-- Eliot (erosen@lij.edu), May 19, 2002.


< font color=red>Issues in rangefinder engineering A report by Erwin Puts

-- Kelly Flanigan (zorki3c@netscape.net), May 19, 2002.

Looks like I red/read too much today!

-- Kelly Flanigan (zorki3c@netscape.net), May 19, 2002.

I can clearly see a difference in the two images - however the sign is not far enough away to be classed as infinity - another test please? To those who haven't read my second post I state again- the error of .4mm is in fact .75mm ( difference between the measured body of the Hexar ( flange to pressure plate) and the M spec. On any 50mm lens, irespective of the angle of the focusing cam/thread ( and I guess the tabbed 50's have a steeper thread), this is a shift of a conciderable distance; 'about' 4m to infinity. I.E moving the lens elements in relation to the film plane by any of the measured variables that the original test reported will cause huge focusing variations. As errors of this magnitude are not being reproduced in real world tests -such as those above. i have to conclude that the measurements on the 3 bodies in the original test are , quite simply, wrong. This new test should be disregarded in relation to the whole Hexar-M compatibility issue. Lets step back a bit here though - I can see no commercial reason why Konica would deliberatly make a mismatch and no technical reason why they cant accuratley manufacture within the spec of leica -I could hand file a lens flange to tolerances smaller than the errors published! What we need ( and I have been arguing for in previous threads) is a proper test involving a good numerical sample of bodies - only then can we put this one to bed once and for all.

-- Johann Fuller (johannfullr@hotmail.com), May 19, 2002.

i wont belabor this (any more than i already have), but moving the focus ring on the 50 cron from 4m to infinity racks the rear element much much more than a fraction of a mm. anyone can repeat this test. you don't really have to measure; the element moves a decent fraction of an INCH. a quick reference to my linhof bed focus scale for 65mm (the closest one i have), indicates about a 7mm movement from 4m to inf for this focal length. the fact is, a .4mm movement corresponds to a very small degree of focus shift, and mite be swamped by dof at most apertures. again, please don't take my word for it. pull out your 50, put the rear element housing against a mark on a sheet of paper, and turn the ring from inf. to 4m. you will see that there is MUCH more than .4 (or .75) mm of movement, much more.

-- roger michel (michel@tcn.org), May 19, 2002.

Hi Paul,

You write:

>> The issue of the pressure plate was just raised in a private correspondance. I did take pains to make sure this factor was mitigated - I waited about a second between exposures on the Hexar to let the geometry settle down, but didn't wait too long to avoid film curl due to "memory" in the film base. However, the amount of difference I see here is much more likely to come from factors like pressure plates than differences in FFD.

I agree that the resolution is pretty good. When you consider that the image was shot with a 28mm wide open at f/2.0, and the enlargement is a 100x200 pixel section of a 4000 x 6000 pixel original, I think that both cameras acquitted themselves admirably. On my screen, the original image (enlarged to the size of the blown- up sections) is 36 x 54 inches. Not too shabby at all. <<

Paul you gave me all the explanations I needed, thanks for the test.

It is particularly interesting to note the resulting enlargement of all the scene would have been 36 x 54 inches. For us, continentals, it means 137.16 cm x 91.44 cm.

At this point, I think we should all stop and think what these values mean.

Personally, for such an enlargement, I will have let my Hexar RF (and would have let my M5) in its bag and took my Mamiya 645 1000 S medium format SLR, at least if this enlargement was to be observed in detail from a close point of view. If it was to be seen at a normal distance of observation to embrace all the scene, then even with the slightly poorer definition observed with the Hexar RF, the difference would have probably not be perceived due to the limitation of the separating power of the human eye (Erwin Puts has exposed this problem in depth on his site). So the difference is practically negligible. And you clearly prove the measurements the allegedly “respectable” sources provided don’t translate in the true world.

Again, referring to practical use, I think the difference is even smaller. Most shots taken with M cameras or Hexar RF cameras won’t be taken on a heavy tripod, moreover with a wide angle set to infinity and the lens at full aperture… So for all intent and purpose, the DOF will take care of the difference. As Roger and others said, the only way to put to rest the theoretical question would be to test a fair number of randomly chosen bodies of each make (and perhaps a random sampling of lenses as the helical should also present very small adjustment problems as I suspect a lens might be adjusted for the infinity for the Hexar RF or infinity for an M body within the accepted tolerances at Leica’s).

So to say it seems to me a non issue at all.

As I consider 400 ISO film my B&W standard it is even less important for me.

If people want to spend twice the price to get an all theoretical amelioration of the definition they’ll never be able to see in real life, that’s up to them, I have no objection, this is their money…

The only unsettled point remaining is to know if even within Leica production the accepted tolerances of fabrication are not such that you are liable to get a M which won’t perform better than the Hexar RF tested and conversely if within Konica accepted tolerances some Hexar RF won’t perform exactly as your M did…

Friendly

François P. WEILL

-- François P. WEILL (frpawe@wanadoo.fr), May 19, 2002.


Gee, and I was told "the camera is not important".

-- Yossi (yosslee@yahoo.com), May 19, 2002.

Friends,

Whatever the other ramifications of a test like Paul's might be (I'm thinking of Andy's points) Paul has answered a practical question for me: If Erwin Puts's bench tests are correct why did so many of us write to say that there is nothing wrong with our pictures when we used Leica lenses on our Hexars?

The answer is that everyone is right. Paul has performed in the field more or less what Erwin performed on the bench. Yes, there is a difference in sharpness and indeed the Leica lens's image is slightly degraded on the Hexar. Yet, Paul's shots are shot under virtually ideal conditions. These are conditions that we very rarely shoot under. In the real world use of Leicas and Hexars there is going to be some camera shake and our focusing will seldom be 100% perfect. It is very likely that our subject will be in motion. We may also using fast film where grain is the primary image degrading factor. We may be shooting wide open with lenses not as perfect as the 'cron 28/2. We may very probably be shooting stopped down, allowing dof to narrow the differences. On top that, we are not likely to blow up our images where the differences that show up in Paul's would be a major factor. And even if we did, the difference would be so small that it might not be an issue unless a similar image was competing with ours.

I have yet to use a Hexanon lens on my Hexar. I have used mostly wide angle lenses--12 to 35mm and occationally 50s. I've found anything over 50mm hard to focus on the Hexar because of the small and darkish finder. A few times I've used my beloved 135/2.8 "googles" lens handheld in difficult lighting and at fairly slow speeds in shooting non-stationary objects (people speaking). Results were what you'd expect under those circumstances-- certainly not perfect sharpness but very good sharpness.

In my practical street photography my Leica,Voigtlander and other lenses' images' successes and failures have been predicated on content and the photographer's technique, not the fine points of resolution.

Because of the limits of the Hexar viewfinder and also because of how I generally shoot candids--at waist level--the wide angle lenses I use are stopped down to maximize dof without sacrificing fast speeds (I try to shoot no slower than 1/25 sec.). For this I need fast film (800 ISO was my lowest speed). This is a different world from Erwin's bench tests and Paul's field test.

My biggest problem with the Hexar was is its slow responding shutter button, which is not important to this discussion.

My recommendation for using the Hexar with non-Konica lenses is simply to stick to wide angle. This would be my advice anyway, given the Hexar's finder.

We can continue making tests and discussing this ad infinitum, but as far as I am concerned the case is for all practical intents closed. We need to at all costs continue to increase the number of beautiful things in this world, as Maxim Gorkii told the young Isaac Babel. And I think we can do that with our Summicron 28/2s mounted on our Hexars if the spirit moves us.

My thanks to everyone, especially Paul, who contributed to lively and very important discussion.

All the best,

Alex

-- Alex Shishin (shishin@pp.iij4-u.or.jp), May 19, 2002.


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