Perfect lens designs are symmetrical, and their sizes and distance from the film/sensor are related to the focal length. Since normal cameras do not have variable flange distances, you can only make perfect lenses down to a certain point, and if you want a smaller focal length (wider lens), then you can't move the lens close enough to the sensor to get a perfect symmetrical design, and so you need to design a lens with retro focal design, which trades off some characteristics for a wider angle of view at a larger flage distance.
The Leica M lenses have a shorter flange distance, and they can have more perfect wide angle lenses than the R. This is also why the Hasselblad SWC with its Biogon is a more perfect wide angle than the Hasselblad V 40mm Distagon, even the latest. In fact, in Zeiss speak, I believe that Distagon means retro focal and Biogon means (nearly) symmetrical, for their wide angle lenses.
mirkoc wrote:
Would you please elaborate that? Why is it so?
It's harder to get a clear (smaller) circle of confusion when the focus distance is longer. A projector is the inverse of a camera. The further I move away the screen, the worse image I got.
JohnJ wrote:
The R 80, hands down, although these two images don't properly compare the two lenses I prefer the R's bokeh. The R is slightly less sharp wide open (albeit at F1.4 instead of 1.9) but has much less CA.
Yes, works well.
That may be so based on the two image that are posted but they have had different treatment during shooting and RAW conversion so it would be unfair to compare them for their colour.
JJ
Despite the different treatment and conversion, I still can see the Leica versus the Mamiya colors that you illustrated here.
It is not always true that by moving the lens further away from the recording medium (film/digital sensor) will attenuate the image quality. To state in another way, it is not always a disadvantage by moving the lens further away from the recording medium (film/digital sensor). The first point which is the type of the recording medium itself and it's property.
In the film case, the closer the lens to the film plane, the less challenge the design of the lens resulting in compact lens with faster f/stop and less distortion while still maintain high resolution and colors and low vignetting.
In the digital case, the lens we are discussing here are film not digital lens, the closer the lens to certain digital sensors (Sony NEX7 and PhaseOne IQ180), the image quality is compromised by color freezing and softness to the corner and in some cases even astigmatism may occurred. Therefore, symmetric (compact) design lens will not do as well as retro focus lens (bigger). However, even the advantage of retro focus film lens on these challenging digital sensors, the image quality is still compromised. The Focal length of the lens become another determinator of proper image quality. Therefore, rangefinder lens from 45-50mm (shortest focal length) are safe with the challenging digital sensors.
So the question one should ask is why focal length from 45-50mm is the shortest focal length limit to work well with these digital sensors and how it ties together slr versus rangefinder lens comparison?
I intend to buy APO extender 2x for elmarit 90, but I did not find any information whether it is compatible? Should I have been putting money in the APO extender? As far as image quality will suffer?
thank you
andrewmodus wrote:
I intend to buy APO extender 2x for elmarit 90, but I did not find any information whether it is compatible? Should I have been putting money in the APO extender? As far as image quality will suffer?
thank you
I think that at the focal leigth 90 & apo-extender 2x the optical quality almost no change, but the aperture is reduced to f/5.6
Alex, are you sure? TCs often have some kind of interlock preventing them to be used with short focal lengths, and I am not sure that the 90 Elmarit-R is long enough...
Carsten -- The R extender will work with any R lens that has telephoto range. It works with my 60/2.8 macro, and even my 28-70! Mine is regular, not APO, but both should function the same.
Gunzorro wrote:
Carsten -- The R extender will work with any R lens that has telephoto range. It works with my 60/2.8 macro, and even my 28-70! Mine is regular, not APO, but both should function the same.
My 2x APO extender (ROM) fits on my 3-cam 60 Macro and 3-cam 90mm Summicron-R. No idea how these combinations perform optically, and it's unlikely I'll take the time to test them because I have better options available.
I see nothing in the photo of the 3-cam 90mm Elmarit-R that would suggest mechanical incompatibility.
Mescalamba wrote:
Worldinlens - are those stitches or HDRs?
No, this is one shot. The s5 has a "hardware" HDR. This makes it very difficult to over-expose the ligths. And as a rule, in the post-processing from fuji I stretch the shadows and a little "paint", and indeed with any other camera in the landscape.
