Do different lenses have different contrast capabilities?

[david_henderson]

I've been using a Mamiya 7 alongside my Bronica SQAi for two years

now. Like others, I'm very impressed with the sharpness and indeed the

colour characteristics of the Mamiya lenses.

 

I think I'm beginning to notice that the Mamiya lenses may be a little

less tolerant of contrast than those for the Bronica - in particular a

greater tendency for shadows to block up with the Mamiya. This may be

down to lens characteristics or of course due to the fact that with an

SLR I can do more to control contrast. I use the same film types in

both cameras.

 

Has anyone else noticed this and indeed is it physically possible?

I'm obviously aware that film varies a lot in its ability to handle

contrast. Is the same true of lenses?

 

Thanks.

[chuck_pere]

Maybe the Bronica has more flare. This could act like film pre-exposure extending the film toe. You would see more shadow detail but it would be lower in contrast.

[jack_congson3]

Hi David:

The most intelligent discussion I have come across of the concept of lens contrast, resolution, and mtf is Lars Kjellberg's article in photodo. Look at the index of articles in Photodo: http://www.photodo.com/nav/artindex.html

and go to Lars's article.

[roger_michel]

my goodness!! yes, different lenses will vary SIGNIFICANTLY in terms of how they render subject contrast. indeed, this may be the most important aspect of lens performance, and is the reason mtf figures are generally stated for both low and high contrast subjects. there was a huge contrast revolution in the 1960s, many say driven by nikon and some of the other japanese mfrs. since higher contrast produces better edge acutance, it generally leads to higher perceived sharpness -- regardless (up to a point, of course) of how well the lens actually resolves fine structures (i.e. line pairs in the typical test). by producing high contrast lenses, the japanese were able to compete with (and largely beat) higher resolution optics from the traditional german mfrs like zeiss and leica. these german firms had always stressed extremely high resolution and lower contrast in their lenses, producing that kind of creamy effect in the midtones that many photogs still prize (and which is manifest in the leica line these days more or less only by the summilux series -- a very old design that has not been revamped since the 60s in any significant way). when people saw the higher contrast nikon/canon snaps, they perceived that the lenses were sharper and started to buy into the new look. soon everybody -- zeiss and leica included -- bought into the high contratst philosophy, to one degree or another. today, although high contrast is certainly the rule (and coatings are a big factor in producing the modern high contrast look), there is still considerable variation among mfrs and among individual lenses in a particular mfr's line. i am not surprised at all to hear about your experience -- i would have been more surprised if you had discovered that the contrast perf was the same (i am also not surprised that the mamiya lenses were contrastier -- i have long felt that mamiya's rep for high sharpness was simply a testimonial to a corporate decision to go high key). everything in life -- including higher perceived sharpness -- comes at a price. you have simply discovered the price you are paying for those "sharp" mamiya rf lenses. by the way, when you speak of the shadows "blocking up," do you mean the hilites -- typically it is in reference to areas of high neg density that the term "blocking up" is applied.

[david_henderson]

To answer a couple of the issues/questions raised in the responses so far.

 

1. Is it flare in the Bronica lenses? Possible, though I don't think so. The Bronica lenses give me well saturated photographs - as good as the Mamiya in this respect albeit that the images will be of slightly different colours. Further, I don't seem to get visible signs of obvious flare more on one system than the other and both sets of lenses are coated.

 

2. Roger - I use colour transparency film all the time. I mean that the deep shadows seem to contain less detail - and indeed less light- than with the Mamiya than with the Bronica. It isn't something that I see on every shot - I guess it's probably a bit like saying I can cope with a 5 stop brightness range with a Velvia/Bronica combination, but only 4.5 stops with a Velvia/ Mamiya combination. This is of course exacerbated by the fact that I can use grads and a polariser much more subtly and accurately on the SLR. But I understand the relevence of your comments, thanks

[roger_michel]

if you are relying on in-camera/in-prism meters for the two cameras, it could be that you are metering the scenes differently. if you are using a hand-held meter, it could be that the t-stop of the lenses are different and/or that there is some moderate departures from the marked stops and true f stops all across the range. mite be nteresting to find some transmission data on the lenses.