Miyazaki san makes modern 24mm, 28mm, 35mm lens in Leica mount using the Cooke triplet formulas and modern glass. I bet one can recreate the Taylor, Taylor & Hobson Cooke look using modern ingredients as well....Originally Posted by Richard Johnson
And remember, Lomo sold a lot of their modern Petzval for dSLR.
Read number 15 in this thread.
I'm with you on this one. Marketing be damned, the only 'digital' lenses are used in fiber optics and opto-couplers, and perhaps some LEDs as well, like those in our remote controls.
I'm pretty sure any lens used in any aspect of 'photography' is 'analog', except perhaps for those still using laser imagesetting techniques to make digital negatives, and of course there might be other digital image-making techniques I've never heard of.
A 'digital' process is anathema to photography, as the result is a '1' or a '0', which doesn't leave a lot of room for tonality. The second you use a larger range (like 0x0000 to oxFFFF) and convert this to grayscale or color, you have a digital to analog (or vice-versa) converter, and the photography part of that is then the 'analog'.
Uhhhh - "digital" has nothing to do with "binary". Your fingers are actually "digits" - the root of the word had to do with using your fingers (ie for counting) - for example a lot of us old guys get "digital" checks of our prostate from time to time. (Bend over, Smile, Uggggh)
When I got into the computing business in 1959 we were still using large scale computers that operated on "base 10" ie decimal logic. I still have a textbook somewhere that spends a lot of pages on how to choose between base 10 and base 2 in the computer design process. ("Planning a Computing System", by Werner Buchholz as I recall)
As a follow on to the previous post (too late to edit it,) the only thing "digital" about a "digital" lens is that it's optimized for a sensor instead of film. In other words, there's nothing digital about the lens itself. Maybe it should be called an "analog lens optimized for digital photography" but that takes up. too much space so they just call it a digital lens.
By the way,"0xFFFF" is still digital - no analog to digital conversion here. The example of "0" or "1" vs "0xFFFF" is more properly a discussion about the degree of quantization inherent in using x digits (binary digits (=bits), duodecimal digits, hexadecimal digits - whatever) to represent some real world (ie analog) value since, unless you use an infinite number of digits per sample, there is no way to represent an analog value that falls between two x-digit values.
Jim, if you find that book, let me know. An interesting part of our computing history.
In any case, yes, think of it as "a lens that is optimized for a sensor instead of film." A digital sensor needs much higher flatness tolerance, also that with the exception of the Sigma/Foevon sensors, all 3 colors must be focused on the same plane (in fact, there is no color sensor site per se, but a color filter on top of the same sensor cells).
I started my working career programming interfaces between computers and analog electrical devices, typically 0-10V signals or 4-20mA loops, but occasionally home-brew light sensors. That's why I referred to a 'digital-to-analog converter', and vice-versa, above. That is the point in a computing system with analog inputs/outputs (such as a 'digital' camera, and I don't mean one with 5 fingers attached to it), where information is transformed from analog to digital or the reverse as the case may be.
A particular computer may be processing 32 or 64 bit words nowadays, but those words are still collections of 32 or 64 discrete bits, which most definitely are set to either 0 or 1 with nothing in between, and none of our commercial processors have yet to crack this limitation. This is inherently unsuitable for photography (unless you like REALLY high contrast), and any lens that is designed to work with such a system (such as the fiber optics I mention above) would be a 'digital' lens according to the most common meaning of the word 'digital' (from google: dig·it·al ˈdijitl/ adjective 1. (of signals or data) expressed as series of the digits 0 and 1, typically represented by values of a physical quantity such as voltage or magnetic polarization). Such a lens would be completely unsuited to photography, having generally as its primary goal the projection or concentration of light in such a way as to ensure error-free transmission of.... digital 0s and 1s, using light as a physical medium instead of electricity.
Obviously Schneider has decided to use 'digital' in a different sense, for marketing purposes. But there is nothing about their 'digital' lenses that make them more suitable for digital sensors than for film. The physics are no different, marketing be damned, and yes I am aware that some people have tried to claim there is a difference (*). Light doesn't care if it falls on a Bayer array or a sheet of Tri-X. This misuse of common words for marketing purposes, especially (as here) when done with the express goal of misleading consumers into thinking they need new 'digital' lenses for their newfangled digital cameras, is irritating to those such as myself who try to use the correct words to communicate ideas. And I say this even though I now work in: marketing. Perhaps in a few years I will admire their chutzpah, but for now I just find it irritating. Like when giant conglomerate Unilever tries to sell me an 'artisan' frozen pizza.
* The closest thing I have seen to a real argument is simply that the newest generation of digital sensors is capable of higher resolution than consumer-grade film, ergo we now need lenses with higher resolving power. And those new lenses are still.... analog.
Ummmm.......guys....Bob *clearly* stated the main deal-breaking difference between analog and digital LF lenses in post #15:
"It will produce an excellent image on film, but they do not cover 4x5", some will cover 6x9cm. All hit optimal aperture around F8 rather then F22 since the digital format is much smaller then 4x5."
My Nikon 35mm 1.4G has been designed to overcome the edge effects of digital sensors and works fantastic with film in my F100...but it COVERS THE FORMAT!
Obviously one can (and should!) now design lenses around the particular requirements of today's digital cameras, not that these are any different from the requirements of film cameras of the same format. The resulting lenses are still: analog. In the case of my Canon EF lenses, they are usually called 'crop-sensor' lenses, to indicate that they don't have the image circle of the other line of EF lenses designed for film or 'full-frame' sensors.
Dude....bottom line, the new digital LF lenses will not cover 4x5 inch film, that is really all anyone needs to be concerned with regarding the topic of this thread, the discontinuation of analog LF lenses.
I could really care less what "digital" format these new lenses cover since digi-crap is not the future of my career and I suspect not the future of those who engage in LF as a hobby.
There is a difference, it is the coverage of the format, or lack thereof...
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