Durst M605: can't focus 50mm Rogonar lens with bigger magnification -

Ian Grant

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However it's only a repro of a Lapla 39 which the OP already has and still won't enable the 50mm f3.5 Ronar or Trinar to focus for larger prints.

A good 50mm enlarger lens can be found for around the same price.

Ian
 

snusmumriken

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BeselerOrNot said:
Yeah.. I tried to get smth local, but the country is small, so is the market.
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@BeselerOrNot, I sympathise with your lens problem, and regret that I have no solution to offer ... but surely (a) the Czech Republic is the urspring of creative photography; and (b) your market is the whole of the EU, without import duties. Good luck!

PS - Feel sorry for those of us in Britain, outside of the EU.
PPS - Because of oppostite market circumstances, I bought a mechanical enlarger timer when in Prague in Soviet times. It still works, and I still use it. The plastic housing is, of course, grey, but at least it isn't marbled grey. (It will be interesting to see which Photrio followers comprehend that!)
 

snusmumriken

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grahamp said:
Marbled grey... A bit like Hammerite, and on a clockwork timer (bzzzz..clunk) with a 2 pin old continental outlet and wooden body. Used it for years. Probably still in a box somewhere!
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Wooden body! Sounds even older than mine. But the marbled grey wasn't paint, it seemed to be the universal colour for communist plastic in the 70s.
 
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BeselerOrNot

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I am happy to report that the issue was successfully resolved. The ordered Durst Neonon 50/2.8 just arrived, and I can focus at the max. magnification now, with the bellows not even fully compressed.

The lens build quality is just another level, compared to Rogonar. And the push/pull design of the aperture ring indeed reminds me of the Pentax power zooms.

I wonder if the lens is multi-coated though, the surfaces don't have that distinctive green/blue-ish cast in reflections..
 
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BeselerOrNot

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Ian Grant said:
it really is not necessary.
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Why do you think so? As far as the light source is full-specrtum, MC should benefit the results, even in BW process. Yes, the FOV is limited in enlargers and no super-bright light source like Sun is expected, plus the lens design is relatively simple with not so many surfaces.

But as long as enlarger optics has coating in general, the MC is just better than a single layer coating (which is optimized for a one wavelength only).


I wouldn't worry about the coating and just enjoy using the lens.
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I surely will. Anyway the setup is not complete, I have to prepare the actual dark room/cabinet itself, not to mention a print drum, easel etc. I live in a small appartment with a single bathroom, can't have it completely for myself. So the dark room/wet room will be two different places. God save the print drum inventor.
 

Ian Grant

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The term Multi Coating is in many ways a misnomer, some lenses had multiple coatings years before the term "Multi Coating" came into general use with Pentax SMC -Super Multi Coated", the critical word is "Super"

From 1938 onwards when CZJ introduced their first T coated lens coatings have gradually improved. A big step change is the mid 1950s when Carl Zeiss (West Germany" introduced well balanced coated lenses, Voigtlander introduce the Color Skopars etc. even CZJ improved their coatings when their Flexon became the Pancolar.

When I used a significant volume of E6 film there was no visible difference between my 55mm f1.8 Super Takumar, or my 55mm f1.8 SMC Takumar. Where Multi Coating makes a significant difference is more complex optical designs, with more elements, and internal air/glass surfaces. Enlarger lenses are not complex designs, there's no extraneous light, negatives are masked in the carrier. So no need for MC.

Ian
 

MattKing

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Multi-coating is most useful in high flare situations, where there are multiple sources of direct and reflected light.
Enlargers are kind of different from that.
 

Hilo

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BeselerOrNot said:
I am happy to report that the issue was successfully resolved. The ordered Durst Neonon 50/2.8 just arrived, and I can focus at the max. magnification now, with the bellows not even fully compressed.
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That's good news ! I am sure you will enjoy using this lens. Also, my hat off to those here who had this figured out already!
 

BobUK

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A thing I don't hear any more is the mention of a Bloomed Lens

The term seems to have gone from the photography vocabulary.
 

Ian Grant

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Blooming seems to have been the term used to cover some early lens coatings like Kodak's Lumenized lenses, these coating were quite soft and often worn off with lens cleaning, I have a few Kodak 203mm f7.7 Ektar lenses (British made) and the coatings of the early ones in the Kodak Epsilon shutter is nowhere near as good as those in Prontor SVS shutters, or Compurs.

In comparison to early Kodak lens coatings the CZJ coatings, Dallmeyer Dallcoated, Wray coated, lenses I have, made around the same time as the early Ektar are quite different. Kodak changed their coating techniques around 1953/4.

Ian
 

Mark J

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Ian Grant said:
The term Multi Coating is in many ways a misnomer, some lenses had multiple coatings years before the term "Multi Coating" came into general use with Pentax SMC -Super Multi Coated", the critical word is "Super"
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Ian, the photo industry has to some extent muddied the waters on the term 'multi-coating'. When coating ('single coating' ) was introduced, it was almost immediately applied to all air-glass surfaces within a lens. This shouldn't really be called 'multicoating'. The term 'single coating' properly refers to the fact that each surface only has one layer of material, usually magnesium fluoride. This does not mean that each surface looks the same colour. It would usually be necessary to vary the tuning ( in wavelength ) on the surfaces in order not to get a green-biased colour shift on the images. You can certainly see this on many lenses of the late-60's and 1970's.

Multi-coating should refer to each surface being coated with more layers, typically three to five . This reduces the reflection value to less than 0.5% over a wider band, ie. over most of the visible 400-700nm band. People with more knowledge of the history of this can add to what I'm saying, but certainly Pentax were one of the first.

I am certain that all premium enlarger lenses from the early-90's are multi-coated - it was industry standard from this time.

Matt, the benefits of multi-coating are less on an enlarging lens ( with no bright solar source ) than for a taking lens, but still relevant. The multiple internal reflection from surface to surface do take something off the local contrast within an image, as well as the overall contrast ( which can in B&W be compensated by an increase in the grade ) . It is in colour work that multi-coating helps more, because the inter-reflections take away some colour saturation, so minimising them on enlarging still helps.
 

Ian Grant

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Mark, I think you misunderstood my comments, I was referring to the use of more than one coating layer on each air glass surface, CZJ Patented 2 layer coatings not long after they began coating lenses in 1938. Multiple coatings were quite common by the mid 1960s, hence Pentax using the term "Super" Multi Coating in the early 1970s.

Ian
 
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