Archived posting to the Leica Users Group, 2001/07/20

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Subject: Re: [Leica] New Newsletter
From: "Roland Smith" <roland@dnai.com>
Date: Fri, 20 Jul 2001 07:28:48 -0700
References: <20010720082656.274002A006@imail.ision.nl>

I would like to receive your newsletter.

Thanks in advance.

Roland Smith
Oakland, California
roland@dnai.com
- ----- Original Message ----- 
From: "Erwin Puts" <imxputs@ision.nl>
To: <leica-users@mejac.palo-alto.ca.us>
Sent: Friday, July 20, 2001 10:28 AM
Subject: [Leica] New Newsletter


> In the past two months, while silent on the Lug (for obvious reasons), I 
> have produced a newsletter for a small group of people, who have a keen 
> interest in the optics, mechanics, engineering, secrets and use of  
> mechanical precision engineered 35mm camera systems. With these  
> afficionados I discussed topics like: a indepth test of the new Hexanon 
> 2/35 lens, the philosophical and ergonomical differences between the M6 
> and the Hexar RF, the essence of the SLR and RF viewing systems, the 
> engineering arguments behind the Hexar/Leica incompatibility, the 
> artistic differences between Provia100, Kchrome 64, the issue of film 
> flatness, the concept of depth of focus, and so on. Find below an 
> excerpt from the latest newsletter.
> If you are interested in receiving the newsletter, send me an email with 
> your address and topics you may wish to have discussed in the future. It 
> is free, no $18 fee for this service.
> 
> 
> ###
> Having established in previous newsletters that there is more to 
> Konica/Leica lens compatibility than the simple measurement of the 
> distance from flange to pressure plate, I did some further research, now 
> testing in real life with 100 ISO slide film all leica lenses from 24 to 
> 135mm on a calibrated M6 and a factory provided Hexar, which had the 
> distance from pressure plate to flange of 27.95mm, thus identical to 
> Leica but differing from the Konica specs.
> As you recall, the Lug was very quick to some simple checks, which in my 
> view were done not to find the truth, but to 'prove' that nothing is 
> wrong. This view has been canonized in Nemeng's FAQ.
> My results are different. I used a tripod, a high resolution test chart 
> and a measured distance of 4 meters. All Leica lenses on Leica body were 
> focused manually several times and the average setting on the distance 
> ring calculated. All lenses were within 3% of the factual distance and 
> the slides showed accurate focus under the microscope at the 40X 
> enlargement. The Leica lenses on the Konica body showed on average a 
> misalignent of close to 10% and that consistently over all lenses.
> I did a special study of the 75mm lens, but not at the allegedly 
> critical setting of 1 meter (which is not that critical if you study the 
> shape of the curve). The 3 meter setting is more critical. I first set 
> the Leica body and the 75mm on the tripod etc. Made a series of pictures 
> and then I kept this distance setting carefully when using the lens on 
> the Hexar. Results (microscope) showed a loss of micro contrast, a drop 
> in edge sharpness and a loss of the very fine detail, including closely 
> spaced lines. Then I refocused the 75mm using the Hear RF system. 
> Results were truly bad: slides were unsharp and only the gross outlines 
> of the test patterns could be detected. I also used the 75mm/hexar at 1 
> meter distance. Results were much more acceptable, but not really good, 
> but not knowing the other results could mislead you in assuming  that 
> the focus was within range.
> 
> I did this test three times on several days, using several films and 
> creating every time a new setting and so tried to eliminate any specific 
> bias. Of course this test is not conclusive, but it does indicate that 
> the Lug has been too quick to bury the subject. But as Bob Dylan used to 
> sing: sleep well, Mr President.
> 
> The monster test of the BW films is underway.
> I had some old rolls of Panatomic-X (20 years old), the film that 
> introduced high resolution acutance photography to 35mm users. I also 
> used the Maco UP25, 64 and 100, which are all versions of the classical 
> Adox high actance series of KB films. And an ortho 25, APX25, APX100 and 
> previous tests included PanF, TM100 and D100.
> To keep it manageable I used one developer (the famous CG512) and tried 
> to develop to the same CI value. You need to do this as otherwise the 
> steeper curve of the APX25 may lead you think this film is sharper than 
> as example a D100, while in fact both are as sharp (seen as recording 
> the same information from the object) but the 25 has higher contrast so 
> the pictures have more punch, which could be sen as more sharpness.
> All pictures were enlarged 14x. which in my view is the minimum to 
> differentiate  meaningfully between films.
> The shots were of a model in an old desolated factory, giving ample fine 
> details, tonal scale and   resolution possibilities.
> The Pan-X showed outstanding sharpness and acutance, but its grain 
> pattern was a bit rough but very tight. It resembled the grain pattern 
> of the APX100, which is a bit finer, and indeed the two films are close. 
> Finest details however were suppressed by the grain pattern. The tonal 
> scale   showed quite subtle grey values, again till the threshold of the 
> granularity noise. The whole atmosphere is an image of very pleasing 
> tonality, gritty sharpness and details painted with broad strokes.
> The UP100 (Adox KB21) has surprisingly fine grain, but on inspection the 
> grain is clumpier but the edge sharpness is low so the fineness is 
> bought at the expense of definition. Overall quality is still 
> commendable and while not up to todays standards, in its day it 
> certainly was a winner.   The Pan-X and KB21 images indicate the 
> progress realized in 20 years of emulsion technology.  In itself of 
> amazing quality, these films lag in all significant areas when compared 
> to todays super stars. But the differences are on the other hand more 
> evolutionary that revolution.
> The APX100 gives images that suit the reportage style of location 
> photography very well. These images have a fine realistic imprint: some 
> what gritty, but with a smooth tonality and sufficient fine detail to 
> make the scene interesting.
> The APX25 has a higher inherent contrast and so small details are 
> recorded somewhat more forcefully. Grain is absent, which adds a creamy 
> tonality to the scene, but on close inspection the recording 
> capabilities are just a small edge compared to the APX100 or PanX. The 
> finer grain  does record the faintest shades of grey values, which adds 
> to the 3D impression of the scene.
> The UP25 (KB14) is very close to the APX25. Grain is slightly more 
> pronounced, but much less so than PAnX or APX100. The tonal scale is 
> identical to the APX25. The intriguing characteristic of this older thin 
> layered, thick silvered emulsion is the edgy grain clumps, which, being 
> very fine, also roughen up the image structure. It makes the picture 
> very lively and especially for model photography and architectural 
> photography adds an effect that can be described as  underscoring the 
> main story.
> Compared to the PanF as example the KB14 is definitely less smooth and 
> its finer details lack the stark micro contrast of the PanF, but all 
> said, this film is a worthy emulsion, that deserves a try. On a normal 
> viewing distance, the main subjects literally jump from the picture.
> The Ortho25 is a trouvaille: I had some films and asked myself: why not? 
> In the same setting, the  prints proved excellent. The skin of the model 
> came out very realistic and I did not notice any  strange grey values. f 
> course there was no red in he scene, so all  other gray values are more 
> or less 'natural".  Sharpness is excellent and grain very fine. The film 
> has a clear base and so  looks very contrasty, even if the values are 
> close to normal. Not a film for every topic, but I am inclined to use it 
> more often and when using some filters can even add some additional 
> tonal scale.
> Definitely a film to try and use for portraits, glamour etc. Take care 
> of red of course. But more versatile than mostly thought of.
> 
> As a preliminary conclusion I have to say that the UP25 and Ortho 25 are 
> very potent films with a  potential for intriguing results that need to 
> be explored. They are not as good as current  top performers, but the 
> distance from a TP as example is less than often imagined. So it is as 
> easy to note that there is hardly any progress in BW emulsions in the 
> last decades or to state that we have advanced a big stride to deliver 
> superior results.
> 
> If you habitually use enlargements below 10X, the difference are even 
> smaller.
> 
> The lesson: try more film than you use now: it will add to your toolkit 
> and visual awareness.
> 
> Next:
> the PanF, D100, TM100, D400 (new).
> 
> 
> Erwin
> 
> 
> 
> 
> 
> 

In reply to: Message from Erwin Puts <imxputs@ision.nl> ([Leica] New Newsletter)