Re: LF vs MF lens quality
I'm sure this will generate aninteresting technical discusion but to me it misses a couple of key points: 1) for any given final print size the magnification from a 4x5 transparency or negative is much less than that required from MF or 35mm thus begging the question of the relevance of doing a one-on-one comparison of lenses from varying formats. Wouldn't it be more useful to shoot the same subject at the same time with comperable lebses from the different formats and then print thesame size and compare the prints (differences in aspect ratios, etc. of course). 2) In addition to the sheer difference in film size the other major reason for using large format is the use of movements which, of ocurse, is not considered at all in this discussion and,while not related,does make a difference on the impression of the final viewer of the image.
Having said all that I am intrigued by what will develop as any tests I have seen usually show much higher resolution on the part of smallr format lenses unless I am misreading something.
Re: LF vs MF lens quality
Serious landscape photography starts and ends with large format. Advantages over medium format:
1) Film size
2) Perspective control/Shifts/plane of focus control
3) Film Development control of a single image
4) Near-Zero curviliear distortion of wide angle optics
5) Interchangeability of various manufacturer's equipment
The are the REAL reasons one would use when making a decision of MF vs. LF.
Re: LF vs MF lens quality
Hello Ted,
Yes, from a film point of view the larger the film area the greater the enlargibility. My very inefficient lens tests should have been made with lenses of the same equivalent focal length. However, I was questioning the old addage that 35mm lenses are better than MF lenses are better than LF lenses. In this addage it was the lens that was the limiting factor not the film - the relatively poorer quality of LF lenses was compensated for, and some, by the larger film format. However, from what I've seemingly found out for myself (increased quality of LF lenses), it is the film (colour and to some extent B+W) that has become the limiting factor. This means that, for whatever reason, LF lenses can be used for MF applications. For ultimate enlargibility, then obviously the larger the film format the better, but if you are only enlarging to, say 16x20", does using the current line of LF lenses on MF limit the enlargement possibilities to this size anymore? Does a 180mm Apo-symmar L equal a 180mm CFi Sonnar on the same piece of colour film? What's the comparison on T-Max100 or Efke? I shan't dare say that LF lenses are on an actual par with 35mm lenses but bearing in mind that the resolution, at least, of many modern 35mm lenses is limiting (indeed degrading) itself with the, for example, introduction of image stabilising (increased number of elements = lower resolution), I suggest the gap may be narrowing. Of course, there are other aspects of lens characteristics that need to be taken into account but with all things being equal....
... and yes, with, MF roll film holders on the back of a LF, I gain movements over using an MF SLR camera. (By the way, using roll film over cropping 4x5" saves a lot of money for me over the long term, especially with the amount of duff ones I take!).
Re: LF vs MF lens quality
Sam,
Let's assume that all lenses are equal and not limiting for MF, and that film resolution is stellar.
The problem that you need to address in your test is focus accuracy.
MF cameras hold roll film flat, perpendicular to the lens axis and at the plane of focus. View camera roll holders vary in quality, and movements must be adjusted to MF machining tolerances to match their focus accuracy. Taking a photo of a wall with on an 8x10 camera's GG is relatively simple since all corners may be checked easily for focus accuracy. The same isn't true for a MF roll back if you intend to get 40+ lpmm in the corners. First, the GG needs to resolve 40 lpmm, and than you need at least a 10X loupe that fits on the GG to see if focus is optimal in all 4 corners. Or you can just assume that it's close enough and stop down a lot. However, if "close enough" isn't perfect, on film MTF (or resolution and contrast) is decreased, often markedly.
If your print can tolerate small errors, the roll backs for are convenient, and the combination offers movements. The MF cameras are much faster to use and results are of high quality and very reproducible. For architecture and work where critical focus and movements are required, nothing beats large GG size.
Anyway, it's been my experience that the "mechanical" issues related to focus accuracy and reproducibility are more important than lens resolution per se.
Mike
Re: LF vs MF lens quality
Sam, in my limited experience it depends more on the lens than on the format. With good lenses, I have the impression (= won't fight to the death to defend the idea) that film, not the lens, is limiting. I've shot one of my better LF lenses against one of my weaker 35 mm lenses, a 200/4 MicroNikkor AIS, and the LF lens was better at all magnifications and apertures tried.
FWIW I shoot 2x3 with, mainly, lenses made for larger formats and doubt I'm losing much, if anything.
Remember that your Contax shoots half-frame 6x9 so 6x9 is going to be more enlargeable. Also remember that your 58, 110, 240, and 400 are all superb. And a roll holder is lighter and less bulky than y'r Contax with its lenses.
My gear can handle lenses up to 480 mm, my four longest lenses are 360, 420, 450, and 480. The 420 is usually longer than makes sense to use, so I doubt y'r 400 will get much use on roll film.
Just get a 6x9 holder to fit y'r Ebony and don't look back. And don't worry so much about optimality. The late Herb Simon got a Nobel for having had the very simple and obvious idea that the optimal level of optimality is less than full.
Re: LF vs MF lens quality
Quote:
Originally Posted by Sam Martin
...... I tested the schneider 58mm and 110mm lens with my Canon 1D MkII and compared them with the 28-70mmL Canon lens. Everything is subjective in these tests so I won't go into details, suffice to say that at equivalent distances all three lenses showed the same resolution at f6.3 through to f11. All began to deteriorate at either side of this (give or take a third stop).
.......
I tested my 110 mm Super-Symmar XL on 4x5 film, and with some shift applied. While the center was sharp at f11, the corners hadn't reached their potential yet. You probably lose a little sharpness in the center by stopping down past f11, but for LF work, it will improve the overall sharpness considering the entire image area. So which is the "best" aperture depends on the format. (As Ted brought up, the reduction of sharpness from the smaller apertures needed for the larger format is made up for by the smaller enlargement required for the same size print.)
Re: LF vs MF lens quality
The German camera magazine did this test in 98 with a Technika 23 with Super Rollex vs then current crop of MF cameras including Rollei 6008 and SL66, Hasselblad 500, Pentax 645 and 67, Mamiya 645, RZ, RB and 66 and Bronica 645, 66 and 67 cameras.
The LF camera lenses used - 65mm, 105/100 and 180mm beat all of the MF lenses from all manufacturers when looking at contrast, resolution and distortion.
We still have copies of the magazine but it is in German but the graphs are understandable in all languages. If someone wants to scan them and post the articles (permission would be needed from Color Foto magazine) I can mail them a copy as long as they are in the US.
Re: LF vs MF lens quality
I think just a look at the ALPA 12 system shows them using mainly large format lens for medium format. Modern lenses are generally quite good, barring any manufacturing or quality control problems. It might be tougher to find a bad lens today, though some of the ultra low cost third party 35mm lenses might qualify.
I have often read the implied better quality of smaller lenses. Maybe that was true at some time in the past, or with a very uneven comparison (modern Zeiss to old AGFA folder camera lens, et al). My other assumption was that large format lenses worked poorly wide open, though I have seen some images that convinced me that was not true either. Perhaps the assumption we should have is that when we buy from the better lens manufacturers, we should expect better lenses.
Ciao!
Gordon Moat
