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01-16-2009, 02:25 PM   #1
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Contrasty lens--always a good thing?

in situation where the lighting is already very contrasty (such as noon time in strong direct sunlight), is contrasty lens still a desirable thing?

Wouldn't you want a non-contrasty lens sometimes, in some situations?

thanks,
donna
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01-16-2009, 03:01 PM   #2
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I dont think that uncontrasy lenses do much on decreasing overall scene dynamic range or contrast. I think their softness is more locally pronounced as a area haze or some added smearing (even if the resolution is high). As for contrast, it may also be referred to color contrast.
http://www.luminous-landscape.com/tu...contrast.shtml
I've also been thinking about this but real life situations usually show its different, but i havnt made any sceintific testing.

Last edited by ytterbium; 01-16-2009 at 03:08 PM.
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01-16-2009, 07:48 PM   #3
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You are mixing up two different types of contrast.

Lens contrast refers to the resolving power of the lens and doesn't have anything to do with overall image contrast. It helps with the apparent sharpness of the lens by giving you well defined edges.

Image contrast is the difference between the white point and black point of the image.
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01-16-2009, 09:53 PM   #4
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"Resolving power" is resolving power..."contrast" is contrast. Resolution is the scale at which you can differentiate between areas reflecting different light wavelengths. Contrast is how much difference is between the two.

High contrast lenses, zeiss for example, often appear sharper than their lower contrast counterparts. But to answer your question, yes, it is certainly possible that these lenses will not be as good at recording subtle differences in a scene, or recording high contrast scenes.

Minolta G lenses, as a counter example, are noted for recording less contrast, but rendering subtle colours and gradients with greater fidelity than a comparable zeiss.

I think you could also compare a pentax 31/1.8 with a 35/2 and see how the 35mm has higher contrast than the limited, but this doesn't make the 35mm the better lens....
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01-16-2009, 10:20 PM   #5
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I just read a really good article on diffraction in the Jan/Feb 2009 Photo Techniques magazine. They point out that as one uses smaller F stops below F8, for most DSLRs, that diffraction rears its ugly head by reducing "contrast" in the image, and then as the aperture gets even smaller, resolution is affected as well.

A high contrast lens sounds good to me!
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01-19-2009, 06:10 AM   #6
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Here's the use of a contrasty lens ... in the middle of a hot summer's day.
If I had used ... say ... my kit lens ... it'd be a much flatter image.

No filters used here ... just my K10D and Tamron 90mm f/2.8 Macro (at f/4.5) ... came out better than expected.

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01-19-2009, 10:19 AM   #7
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I prefer constrasty lenses. If the image/print is too contrasty, that can be fixed in post processing, film or digital. If the image does not have enough contrast, the image goes in the round file.
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01-24-2009, 04:25 PM   #8
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Originally Posted by Canada_Rockies View Post
I prefer constrasty lenses. If the image/print is too contrasty, that can be fixed in post processing, film or digital. If the image does not have enough contrast, the image goes in the round file.

In essence, I agree with the above statement. But I don't claim to be an expert on which lenses are more or less contrasty than others, but the other day I had an interesting experience with just one lens. We had experienced a light snow fall in the before dawn hours, and I took several shots at about 8 am. They were very flat - not contrasty at all. Then two hours later, at about 10 am, I took some more shots and much to my surprise they were of high contrast. These were with the exact same lens, a Tamron 28 to 300 mm, all taken at roughly 50mm setting. So, my conclusion is, the light level has a great influence on contrast, irregardless of the choice of lenses. I'm sure this will stir up comments, i.e. those who might say "everyone knows this" and those who will argue with my findings. Oh well, that's life!
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01-24-2009, 09:53 PM   #9
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That's a neat observation - I'll have to try it out for myself. Thanks.
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02-23-2009, 03:44 AM   #10
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moved to SLR lens section.
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02-23-2009, 03:47 AM   #11
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go to the Sean Reid site and read his essay on Sunny day lenses.
http://reidreviews.com
(Is is a pay site though)
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