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 Mamiya RZ Lenses as Alt | |
So when I departed on this quest of medium format glass adapted to smaller formats I spent a lot of time perusing forums, flickr, etc. for sharp Medium and Large Format lenses. I read many posts, MTF charts, test reports, reviews and opinions about the sharpest glass. There are even a few current threads on various forums asking similar questions.
I did it the old-fashioned way, I lurked and combed the threads for knowledge.
I had a few heuristics to guide me:
The notion that the image formed by the lenses would be better in the center of cropped format.
The MTF, LP/MM measurements would be not directly applicable, but would be a good guide.
The guess that older lenses would be less expensive than lenses purchased new, and hence a wider net could be cast.
That I knew I would not have the Depth of Field of the larger frame lenses and that the cropped image would be different from what the lens was designed to be.
And finally, that newer sensors would have the spatial resolution to make use of the higher performance of the higher performance lenses recommended.
So far, all of my heuristics have been born out to my satisfaction.
Using first the a850 then the a6000 and finally the D810, I\'ve been making images that approach the quality that satisfies my desire for a balance between sharpness, color rendition, contrast and dynamic range. I\'ve gotten photographs that have that elusive dimensionality that seems to jump out of the print or the screen. Not that this is impossible with other lenses for the correct format and mount, but those are indeed not as frequent.
I read a bit about sharpness and resolution. here\'s one that got me started with crunching numbers:
http://photo.blogoverflow.com/2012/06/the-realities-of-resolution/
Therein he talks about Spatial Resolution, MTFs, diffraction both in lens and sensor and the interactions of all. So with those guidelines I did some calculations of my own regarding sensor size and resolution measurements.
Turns out the newer, denser sensors have much higher Spatial Resolution as well as increasing Megapixels.
------------------------- spatial-res ----- image-res
Nikon DF ------ 68.61 lp/mm ----- 1640 lp/ph
Nikon D810 ----- 102.33 lp/mm ----- 2456 lp/ph
Sony a7r --------- 102.33 lp/mm ----- 2456 lp/ph
Sony A7S --------- 59.83 lp/mm ----- 1424 lp/ph
sony a6000 ------ 128.84 lp/mm ----- 2012 lp/ph
ML Credo 60 ------ 83.31 lp/mm ----- 3366 lp/ph
phase one p25+ -- 55.73 lp/mm ----- 2040 lp/ph
p1 iq280 ------------ 95.94 lp/mm ----- 3876 lp/ph
p1 p65+ ------------- 80.31 lp/mm ----- 3366 lp/ph
p1 p40+ ------------- 83.34 lp/mm ----- 2742 lp/ph
hasselblad cfv50c - 94.22 lp/mm ----- 3100 lp/ph
samsung nx1 ----- 137.57 lp/mm ----- 2160 lp/ph
pentax 645Z -------- 94.10 lp/mm ----- 3096 lp/ph
canon 5Ds R ------ 130.91 lp/mm ----- 3142 lp/ph
The above are a rough table continuing the work from the linked article showing spatial resolution as well as image resolution. As you can see the a6000, the NX1 and now the upcoming Canon 5Ds R are capable of 125+ LP/MM and the 5DsR will have full frame Depth of Field to boot.
I figured the lenses highly correlated to high LP/MM like the Hasselblad 110mm F/2 Plannar FE would perform to a level of excellence similar to that on their native systems sensors/film. And if indeed the lenses outresolve the sensors the newer, denser sensors would perform perhaps even better than the Medium Format systems.
Turns out I was mostly right. The sharpest, most contrasty, best color rendition, flat field, low distortion lenses of years gone past, lenses which cost as new as much as the top performing lenses of today, are spectacular performers on today\'s denser sensors. So I contend that while these lenses won\'t have the same look as 6x7 film or Medium Format digital backs they do have an excellence and performance that is really hard to be equaled, for the cost, with current and former full frame lenses. I haven\'t tried them all, and there\'s about 100 lenses on my list to get, of all formats, and for use in all the formats I shoot, which is now 135 film and digital, 6x6, 6x7 and 4x5 film and hopefully one day soon, MF digital.
So directly to the RZ67 glass, which with I have fallen in love because of their color renderings as well as sharpness.
Here are some more with the M 65mm F/4 L-A
Here\'s the great Mamiya Macro M 140MM F/4.5 M/L-A, Extension Tubes No.1 & No.2 on the D810
And without tubes on the a6000
And some Pentax
SMC Pentax 67 Soft 120mm on D810
SMC Pentax 67 55mm F/4
Hasselblad 110 F/2 Plannar FE on a6000, amazing colors.
The 80mm F/2.8 Schneider Xenotar PQS HFT on D810, spectacular colors.
Of course I have on my list the Zeiss Otus\', the nikkor 200 F/2, the Schneider PC-TS\', and of course the upcoming Canon 5DSR, but those will take many years to obtain, and I would hazard that I am approaching such levels of quality with my older MF glass, right now.
Not, speed, mind you, but color rendition, tonality and sharpness. The real improvements of late I feel are the control of aberrations in the newer glass, which are simply amazing. The older lenses have longitudinal chromatic aberrations that are mostly correctable in modern software, but the newer glass hardly has any.
So my quest is hardly over, but my heuristics are doing me well, and I\'m not alone in that thinking, look at the similarity between the Rollei PQS HFT 90MM Makro and the Schneider PC-TS 90mm f/4.5 Makro Symmar. That .5 of a stop is for the light loss for the flange focal distance and I bet Scnheider engineers said:\"We could put a PC-TS mechanism in the space the adapter would take.\" So I bet the optics are almost exactly the same, except with modern Schneider HM glass.
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PS Ravi Babu, sorry I missed your question before, here is a link:
http://web.archive.org/web/20050403172108/http://medfmt.8k.com/bronross.html
(You\'ll have to copy & paste the whole line, as the url and the tables are broken by formatting here.)
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