analogue lens with digital back

[Frank Buchner]

Does anyone know any analogue lenses work good with digital?
I have experience only with Sinaron W 90/4.5 - (excellent job) and Sinaron S 150/5.6 (very, very, very bad).
I would be grateful for more information than this.

Frank Buchner

[SergeiR]

Its a lens. It projects. It would work. Results will depend on what kind of "digital" you got.

[Jim collum]

for the most part a 'digital' lens is just a marketing label. I've used old scratched meniscus lenses with my digital back, and it gave me exactly the look I wanted for that image. It might be better to post what it is you're looking for (resolution? lack of CA? flare resistance?)


Does anyone know any analogue lenses work good with digital?
I have experience only with Sinaron W 90/4.5 - (excellent job) and Sinaron S 150/5.6 (very, very, very bad).
I would be grateful for more information than this.

Frank Buchner

[lenser]

In small format, I use my Nikon D700 with a PB-4 bellows and a badly scratched version of the 135mm bellows Nikkor (fill the scratches with black magic marker to reduce or eliminate flair) and get incredible results even at high enlargement levels. As long as it's a good lens, or yields the kind of "look" that you appreciate on film, you should get similar results with digital.

[Daniel Stone]

Frank,

my "meager" understanding of MF digital is that LF lenses of pre-2000 vintage aren't as "good"(lp/mm, resolving power...) as the "digital"-designed ones currently on the market. If you're looking for ultra high resolution, then you'll want to look at the most recent offerings by Rodenstock and Schneider. However, these come with a hefty price tag to match.

The "digital" lenses are designed to deliver maximum resolution, but really don't offer much in the way of excess image circle outside the size of the sensor. This, IMO, is quite limiting. Lenses designed to be used with film(so to cover 4x5, or larger, depending on model) were designed to deliver high quality, but also allow for movements. There's a tipping point when one can have movement capabilities(to correct/create distortion, or use rise/fall/shift, etc...) but with a little less "quality" in resolution terms, or get super hi-res but with vastly smaller coverage.

Its a give and take. Later model lenses such as the APO Symmar(Schneider), APO-Sironar-S/Sinaron-SE(same lenses, just different names on the barrel), or the Symmar XL line of lenses are all terrific on film. I've used models from all 3, and all delivered tremendous resolving power to the film.

Now, whether it'll satisfy your needs for MF digital use, IDK. Only you can make that call. Me, I compared drum scans of MF, 4x5 and 8x10 film(all forms/emulsion types) with the latest digital backs, and IMO, film still wins.

But what you're looking for in and end result will vary from user to user. Some might think that using a 150yr old petzval lens on a modern digital back will give them the desired results. More power to them. But compared with a current lens, it'll be vastly insuperior in terms of resolving power.

-Dan

[rdenney]

Sometimes, digital lenses have a bit of a retrofocus design to illuminate the sensor at closer to a right angle, and to make the short lenses required by small sensors mechanically possible on cameras with movements.

Sometimes, digital lenses are optimized to provide a different MTF response to avoid aliasing and to make images appear sharper when using digital sensors.

Sometimes, digital lenses are optimized to support greater enlargement ratios (because sensors are generally smaller than film), though film lenses also benefit from that optimization.

Sometimes, digital lenses just have a different label.

My experience is that any lens designed before the digital age does the same thing using a digital sensor as it did using film (whether that be good or bad), and any lens with "digital" in the label does on film what can do on a sensor (if it has the coverage).

Rick "who uses lenses that 1.) provide pleasing images, and 2.) are affordable" Denney

[Lynn Jones]

There is a huge difference between digital and film. Digital light rays must be perpendicular to the sensor. If over 4 or 5 degrees off, first you lose some light and then you lose it all. Most of the early digi cameras lost 35% to 40% of their images for that reason.

Older high quality lenses can be excellent with digital but they have to have long enough actual focal lengths so that the light rays are reasonably close to parallel. The first camera company to design for this was Olympus, followed by Sony, followed by Pentax, you'll have to guess about the 2 who were the slowest.

Among the lens makers, Tamron was the first.

Lynn

[rdenney]

There is a huge difference between digital and film. Digital light rays must be perpendicular to the sensor. If over 4 or 5 degrees off, first you lose some light and then you lose it all. Most of the early digi cameras lost 35% to 40% of their images for that reason.

Older high quality lenses can be excellent with digital but they have to have long enough actual focal lengths so that the light rays are reasonably close to parallel. The first camera company to design for this was Olympus, followed by Sony, followed by Pentax, you'll have to guess about the 2 who were the slowest.

Among the lens makers, Tamron was the first.

Lynn

Dr. Jones, I don't know if this is still as true as it was with earlier sensors. I use a 16mm Zenitar fisheye, which is an old, old design and a cheapie Russian lens, with a Canon 5D and I do not notice significant darkening in the corners. Like all short SLR lenses, it is a retrofocus design, but not by that much. I have also used other old, short lenses, such as a 28mm f/4 Schneider Curtagon, probably made for the Wirgen Edixa, on my Canon with no surprises (other than I had to file down the rear of the old M42 mount to clear the reflex mirror). That lens probably dates from the early 50's. And then there's the Sigma 14mm f/3.5 that seems fine (except for the unrelated problem of ghosting flare), and though it's a modern-era autofocus lens (unlike the other two) it certainly predates digital cameras.

It might be a bigger issue with a non-retrofocus lens like a Super Angulon, but for sensor sizes these days, probably the only such short enough to make a difference is the 47. The shorter lenses are all retrofocus designs to straighten the incidence angle. Anything short enough to be really wide on a digital back (scanning backs excepted) is already a "digital" lens.

Rick "who routinely sees more darkening with the 47 on film than with the equivalent 14 on digital" Denney

[goamules]

I don't have a fancy, large sensor digital, just a micro 4/3 Panasonic G-1. But I've used everything from 1920s petzvals to 1950s Canon, Leica, and Russian rangefinder lenses on it with excellent results.

[Frank Buchner]

Ok. Thank you all for your reply, but I need to make something clean. First of all, I meant digital back with the LF lens. Technically, I know roughly what is the difference between "analog" and "digital" lenses (of course, the more knowledge is better).
I have good experience with Grandagon - N (Sinaron W) 90/4.5 which in my tests with a digital back was a sharp, high contrast, and gave it a realy picture (bit to much Chromatic Aberrations).
I really like this lens with the film (for a pretty picture) and I'm glad that it works with a digital back.
I ask you a similar experience with other LF lenses (not digital).
They are cheaper, more available on the market, and give a nicer (mostly) picture than the "digital" lenses,
but the contrast and sharpness are often not good enough for digital back
thank you very much

Ps. I apologize for not the best English language

Frank Buchner

[Emmanuel BIGLER]

Digital light rays must be perpendicular to the sensor.

I disagree, but depends on what 'digital' means.
If digital means 'any kind of silicon image sensor with a Bayer aray', then I definitely disagree, look at the specs of this Kodak 39 Mpix sensor: silicon alone is perfectly able to detect slanted rays. See figures 18 & 19 page 8 of this paper.
www.kodak.com/ek/US/en/31Mp_and_39Mp_Full-Frame_CCD_paper.htm (http://www.kodak.com/ek/US/en/31Mp_and_39Mp_Full-Frame_CCD_paper.htm)
The 39 Mpix sensor does not have micro-lenses.and still exhibits an efficiency of 70% for slanted rays at 40° of incidence. This loss of efficiency is less that the "natural" loss of any classical large format lens @40° of incidence (80° of total field angle).
For example a classical 105° wide-angle lens only delivers 45% of illumination at 40° off-axis (data taken from Schneider's specs for the SA 5,6-75mm classical WA lens). It means that one can use this sensor up to 45° of incidence (total field 90°) without noticing that some kind of "digital absorption of rays" occurs inside, the phenomenon will be hidden behind the natural light fall-off common to all quasi-symmetrical WA lenses.

Hence, micro-lenses are the issue, i.e a component 100% analog-optical and 0% digital, not silicon, and not the analog-to-digital converter behind ;)

Not kidding : medium format sensors used in professional backs do not all feature micro-lenses. Sure, the ISO sensitivity, in consequence, is low, but not lower than our good ol' film.

The last generation of "digital" lenses from Schneider-Kreuznach and Rodenstck deliver superb results to sensors with no micro lenses. The design of those modern WA lenses belongs to the family of quasi-symmetrical designs although a tiny amount of retrofocus design is included in order to keep the back focal distance, i.e. the (last lens-element to sensor) distance manageable at infinity.
And you can correct light fall-off either with a centre filter (Rodenstock recently introduced a new kind of optical centre filters), or by post-processing, as usual.


P.S. to the best of my knowledge, Kodak sold its silicon sensor division to semeone else at the end of last year ...

[Frank Buchner]

I found the article very useful where there is something about this. Someone more familiar with this type of information on the web?
http://www.luminous-landscape.com/reviews/cameras/digital-ebony.shtml

[Frank Buchner]

Nice information about Rodenstock sironar and Schneider super symmar on this forum http://forum.getdpi.com/forum/medium-format-systems-digital-backs/29738-iq180-quality-older-large-format-lens.html

[Michael E]

A thought for your further testing: During the Photokina 2010 I talked to a Rodenstock engineer. He took over an hour to explain the latest "digital" lenses to me. One thing that stuck to my mind: These lenses have to be used at wide apertures. The examples that he showed on a computer screen illustrated that the full resolution was available in the center at f4, the corners were fine by f5.6, everything over f8 severely suffered from diffraction. This is not compliant with the old ways of LF photography, so make sure to check for the best aperture of any tested lens.

Michael