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Micro contrast and m4/3 lenses
- Thread starter dgrogers
- Start date
Makinations
Veteran Member
The original Panasonic 14-45 OIS kit lens, the Panasonic 20mm f1.7 and the Olympus 45mm f1.8 stand out among the lenses I own.
Supremely Lead Tedolph Zombie (tm).
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Supremely Lead Tedolph Zombie (tm).
Macx
Senior Member
I believe it's the usual suspects: the Olympus M.Zuiko 12mm f2, the Panasonic Leica Summilux 25mm f1.4, and the Olympus M.Zuiko 45mm f1.8.
Tim in upstate NY
Veteran Member
. . . I have all three of these and I agree.
clengman
Senior Member
What the eff is "microcontrast" anyway? There are lenses that are sharp and lenses that are not as sharp. There are lenses that have lower light dispersion and/or less internal reflection that lead to better contrast. Is there some physical basis for this quality of "microcontrast" or is it just a word people use to describe a lens they like?
Just askin'.
Just askin'.
novice7
Well-known member
Contax Planar lenses are know for high micro-contrast.
Adrian Harris
Veteran Member
I have a 14-45 and it realy is good. I do not really rate the 45-200.
However, by far the sharpest by far I have seen - and own, is a Voigtlander 90mm manual prime. The images are so sharp you could cut yourself on them. Sadly on the M4/3 it works out at 180mm equivalent in FF terms, so has only limited uses. I also have a Voigtlander 75mm which again is quite a lens.
Their downside is that on a Panasonic the are not stabilised
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Adrian
http://www.t1000.co.uk/photography/gallery1/
http://www.t1000.co.uk/photography.htm
However, by far the sharpest by far I have seen - and own, is a Voigtlander 90mm manual prime. The images are so sharp you could cut yourself on them. Sadly on the M4/3 it works out at 180mm equivalent in FF terms, so has only limited uses. I also have a Voigtlander 75mm which again is quite a lens.
Their downside is that on a Panasonic the are not stabilised
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Adrian
http://www.t1000.co.uk/photography/gallery1/
http://www.t1000.co.uk/photography.htm
clengman
Senior Member
I'm not doubting that it's a term that gets tossed around a lot. I see it all the time. Just wondering if anyone can explain what it actually means . Physically or qualitatively.
Microcontrast is definitely a lens property. A lens with high microcontrast is one where details stand out more in relation to each other.
Acutance, or sharpness, is a form of microcontrast--nothing to do with the actual resolving power of the lens, but everything to do with the end "look" of the image.
Microcontrast is represented on MTF charts by whichever curve is the coarser measurement. The fine measurement is resolution.
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http://www.photoklarno.com
Makinations
Veteran Member
It refers to the contrast around a sharp edge. Some lenses define an edge better than others.
I usually use the term "contrasty" rather than "microcontrast".
Supremely Lead Tedolph Zombie (tm).
I usually use the term "contrasty" rather than "microcontrast".
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Supremely Lead Tedolph Zombie (tm).
clengman
Senior Member
Okay, so I understand how it can be quantified. Thanks. Is it fair to say that it doesn't result from a single physical property of the lens and that rather it's due to combined effects of properties that effect sharpness (figuring of the lens elements, correction of aberrations) and those that effect contrast (low dispersion glass and coatings and better control of internal reflections)?
Thanks for the explanation.
Thanks for the explanation.
Guy Parsons
Forum Pro
Micro contrast and local contrast seem to be interchangeable.
Basically much the same can be done in post process fiddling with Unsharp Mask. Use maximum radius and fiddle the effect with the other controls, use carefully and the local contrast picks up nicely for most lenses.
Paint Shop Pro used to have a control called "clarify" and from experiments it seemed that it was the USM trick. Can't seem to find that in the latest versions so USM now does the same improvement, followed by of course the proper USM fiddle with proper small radius to get sharpness to suit the display or print size.
Can't make a Holga lens into a Leica but does make worthwhile improvements to most shots.
Regards........ Guy
Basically much the same can be done in post process fiddling with Unsharp Mask. Use maximum radius and fiddle the effect with the other controls, use carefully and the local contrast picks up nicely for most lenses.
Paint Shop Pro used to have a control called "clarify" and from experiments it seemed that it was the USM trick. Can't seem to find that in the latest versions so USM now does the same improvement, followed by of course the proper USM fiddle with proper small radius to get sharpness to suit the display or print size.
Can't make a Holga lens into a Leica but does make worthwhile improvements to most shots.
Regards........ Guy
It's not the same. If the lens can't natively capture the slight variances in light, the sensor can't record it.
It's something I used to do all the time on my old Sony P&S. Found it completely necessary on it. Stopped using that technique completely on my E-1 because it didn't help images at all.
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Completely infatuated with the "OMG"
http://www.luminous-landscape.com/tutorials/understanding-series/lens-contrast.shtml
Completely infatuated with the "OMG"
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Completely infatuated with the "OMG"
Makinations
Veteran Member
That can help but it really isn't the same. You can end up with a lot of artifacts that you don't get with a naturally contrasty lens.
Supremely Lead Tedolph Zombie (tm).
--
Supremely Lead Tedolph Zombie (tm).
clengman
Senior Member
Cool. Thanks for the link. So baffles and flocking for global contrast and coatings and fewer glass-air interfaces for local contrast (plus good lens figure and optical correction if you want high local contrast across the field)?
Detail Man
Forum Pro
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"The Pinhole Camera Revisited or The Revenge of the Simple-Minded Engineer" is quite interesting:
http://www.biox.kth.se/kjellinternet/Pinhole.pdf
Check out the "Pinhole Camera MTF (modulation transfer function)" graph, and check out the simulated images that follow in the referenced paper. The gist of it (as stated in the paper) is that:
In order to produce a sharp-looking image, the imaging system must have high MTF values at low and medium-high frequencies. MTF curves that drop rapidly as the spatial frequency increases will produce fuzzy-looking images, even if they extend out to high spatial frequencies .
I thought that some readers might find the paper to be thought provoking in relation to conceptual assumptions that a MTF that extends to higher absolute spatial-frequencies necessarily equates to the visual perception of a "sharper image". The images in this paper appear to demonstrate otherwise - and indicate that human visual perception in this respect is not as simple as "more is better" (where it comes to merely assessing the maximum spatial-frequency response).
This human visual perceptual phenomenon may have some relevance to recent discussions here ...
... the subjective sharpness of a print corresponds to the area under the MTF curve between the spatial frequencies of (0.5 x magnification) and (2 x magnification) when spatial frequency is plotted on a logarithmic scale .
... if we make an 8x10 (or 8x12) print from a 35mm negative we have to magnify the negative by a factor of 8 (since the negative is approximately 1" x 1.5"). So as far as the SQF is concerned, the area under the MTF curve of the lens between 4 and 16 cycles/mm is then what really counts .
http://www.bobatkins.com/photography/technical/mtf/mtf4.html
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Note: "Local Contrast" (Unsharp Masking with very wide Radius on the order of 15-60, and very low values of Strength) is (IMO) a rather crude technique that is only appropriate for "emergency surgery" on images with extremely low contrast-ratios and/or shot in foggy or hazy environments. The "Clarity" control in Lightroom (and perhaps other Adobe apps, as well) performs Local Contrast
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