Lynn (or anyone else)
Based on your experience, is something with close to the performance of the XLs but faster achievable? The one thing that would persuade me to open my wallet given I have a 110 XL f5.6 would be a 110 or 120 at f4 or f3.5 that performed nearly as well as the XL...
David.
If you have the money, honey, Rodenstock, Schneider, and Zeiss have the time.
Nothing personal, but I doubt you can afford a one-off.
No offense taken - my question was 'is it possible?' I honestly don't know if it is. The Xenotars, after all, relied on very high refractive index glass which one wouldn't (and in most countries couldn't) use today. Perhaps you can fake the thorium glass effect with barium, perhaps you can't. I don't know, and - nothing personal - I suspect you don't either.Originally Posted by Dan Fromm
Don't forget Cooke, who is making short runs of specialized LF optics, or Schneider's
recent (albeit expensive) additions for ULF applications. These particular items serve
a specific niche and therefore have a realistic if limited market. Likewise, Schneider's recent 360 dialyte. But as long as the overall economic situation leads to
all kinds of dream and cult lenses suddenly appearing on the used market, and plenty of general-purpose lenses at cheap prices, what's the incentive?
Of course I don't know. But I am aware of progess in mapping lenses that hasn't trickled down to plebeians like me. It gives me hope that you can realize your dream if you have the money to pay for it. I'm not sure you'll like the lens if you commission it; it will likely be large and heavy.
Re Xenotars, I have a relatively ancient 80/2.8 in hand and it doesn't have the mark of the devil, sorry, of thoriated glass. Xenotars aren't comparable at all to the XLs, different design family and quite narrow coverage. I also have an old 80/2.8 Planar whose glasses are water white too.
I don't believe that thoriated glass is needed to make a fast double Gauss type. You may be thinking of glass with a high lead content. Loss of those types because of changes in EU regulations forced a redesign of the 38/4.5 Biogon.
Cheers,
Dan
I don't think we have anything to worry about. Something analgous is going on in the
world of small format. When Nikon stopped virtually all production of classic manual
focus lenses, Cosina stepped in and started making better than ever lenses to fill this niche under the Zeiss label, which seem to be selling well even at high prices.
But the trend in LF is toward more compact and portable lenses with smaller max
apertures, not huge pieces of glass. At the moment, only Cooke seems interested in
the retro LF portrait market.
Maybe you do have something to worry about. At Photokina we were told by Rodenstock that Copal has raised the price of their shutters, to the lens manufacturers, 100%. This is similar to what Prontor did about 20 years ago to the price of Compur, Prontor Professional and Prontor Magnetic shutters just before they came off the market. As I mentioned in an earlier thread Rodenstock introduced their new E-shutter at the show, partially as an option for future shutter business. But this shutter is only available in 0 size and the Rollei shutter is only available in 01 and 1 sizes. So the larger lenses in a 3 shutter could have a problem in the future. Also, the supply times for raw optical glass has increased drastically.
But with all that Roodenstock did inroduce their new 32mm focal length lens at the show for digital work with view cameras as well as for roll film work on view cameras.
Thank you - interesting report.
Technology does not always move forwards. Sometimes, it moves backwards. The peak of steam engineering was what - 1920? 1930? I suspect that for all the progress in other areas they could build a higher performance steam engine in 1910 than in 1960. I have no idea if this happening in optics: but it might be.
As I hinted, part of the issue is safety standards. High refractive index glass gives you more options. But high refractive index, so far at least, requires nasty materials: talk to anyone who visited Jena (home of Zeiss) in the 80s if you don't believe me. You can do it safety and with good environmental protection, but it is really costly. So you try to fake it with more elements and higher order surfaces instead. That's fine, mostly, but the extra degree of freedom high RI gives you is I suspect useful at the limit. Could someone who really knows about this stuff comment and cure our ignorance?
David
Well, I was already thinking of shutters rather than glass as the weak link in design. If we're talking about big fast lenses in anything other than relatively short focal lengths, the necessary shutters are already gone, and I don't see why anyone would want to make barrel lenses for antique shutters, especially for a tiny potential market.
With plasmats it is pretty hard to make these lenses at a higher speed, shift of focus and field curvature is pretty hard to cure. With lenses like the Xenotars, higher speed works pretty well. As Bob says, however, shutter costs have gone completely out of sight and volume is getting lower and lower.
Lynn
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