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 how to know if a lens has good microcontrast ?



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January 04, 2016, 06:26:59 AM
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Offline lensoreat

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how to know if a lens has good microcontrast ?
« on: January 04, 2016, 06:26:59 AM »
been reading about this ( something i never really paid much attention to before ) lately,  but ....  not really sure i 'get' it...... 
how important is microcontrast ?   

January 04, 2016, 11:39:32 AM
Reply #1

Offline Pacerr

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Re: how to know if a lens has good microcontrast ?
« Reply #1 on: January 04, 2016, 11:39:32 AM »
A lens?  Snake oil, smoke an' mirrors. A best it's the presence of contrast in image details but it's possible to have a sharp image with low contrast.

Only an image can reveal "contrast". Any hardware or sensor characteristics that contributes to flare or optical aberrations can reduce contrast in an image. When reduced contrast is noticeable in image detail some folks might refer to that as a "lack if micro contrast".

There is no definition for what constitutes micro contrast.  Best to simply observe that a given camera and/or lens combination seems to produce a more pleasingly contrasty image than another combination in similar circumstances.

Search on: ' lens micro contrast '
H2  -  I'm not gettin' any smarter in my old age -- I'm just finally beginnin' to run out of really stupid things to do. Doesn't mean I'm not tryin' though.

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January 04, 2016, 09:29:27 PM
Reply #2

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #2 on: January 04, 2016, 09:29:27 PM »
is it not the same as dynamic range ?   basically ?   maybe not.   been reading about it,  but still kind of confusing.   i guess just buying good lenses is the best thing 
somewhere i read that the lenses with fewer glass elements in them produce better micro contrast,  as the more glass the more flat the image can be. 

January 05, 2016, 01:13:20 AM
Reply #3

Offline Pacerr

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Re: how to know if a lens has good microcontrast ?
« Reply #3 on: January 05, 2016, 01:13:20 AM »
is it not the same as dynamic range ?  
  i guess just buying good lenses is the best thing  
     lenses with fewer glass elements in them produce better micro contrast,  

A text image = "pure" black and white (sort'a) = zilch for 'dynamic range -- but perhaps may have "perfect" (micro?) contrast.

Can't beat 'good' lenses as a component in sharp pictures. Again, there's no exact definition for 'micro contrast just like there's no definition for 'good' bokeh.

Gotta be careful about lens discussions. Lots of stuff that was relevant years ago is no longer necessarily true even though it's still repeated today. Not only has the nature of glass itself changed, the means of shaping lenses has changes as well. If all light rays passing through a lens were perpendicular to both surfaces there'd be no issues at all since there'd be no 'rainbow-like' refraction of various colors. Ultimately it's some sort of refraction that contributes to loss of contrast (and sharpness) that's not otherwise caused by flare. Modern glasses and asymmetrically ground or molded lenses (all those alphabet groups in lens 'names') allow more bending of light rays and minimize the effects of refraction without increasing optical aberrations which allows for shorter, lighter lenses* than possible half a century ago. So fewer elements isn't necessarily true today -- especially when considering zoom lenses.

http://www.tamron.co.jp/en/monozukuri/tour/

http://www.tamron-usa.com/lenses/technology.php

* There's a reason a pirate's 'spy glass' was two feet long -- to minimize the amount of refraction (bending of rays) to attain useful magnification using ancient glass without inducing horrible PF.

« Last Edit: January 05, 2016, 01:30:03 AM by Pacerr »
H2  -  I'm not gettin' any smarter in my old age -- I'm just finally beginnin' to run out of really stupid things to do. Doesn't mean I'm not tryin' though.

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January 05, 2016, 08:43:39 PM
Reply #4

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #4 on: January 05, 2016, 08:43:39 PM »
interesting,  pacerr,   though i have no real idea about all the technical aspects of this stuff,   too cerebral or something .   
the only lens i really think i've had that may  have had great micro contrast is the  fa 31.    just something about the images from that particular lens .   
few of my other lenses have good sharpness and seemingly good contrast,  but darned if i know if they have good micro contrast.
i'll have to keep investigating this.   

January 06, 2016, 04:50:44 AM
Reply #5

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #5 on: January 06, 2016, 04:50:44 AM »
dare i ask :  why isn't this good micro contrast,   w/ smc k 50 1.4 lens. 

January 06, 2016, 04:52:17 AM
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Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #6 on: January 06, 2016, 04:52:17 AM »
or this :   smc takumar 28/3.5

January 06, 2016, 05:32:16 AM
Reply #7

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #7 on: January 06, 2016, 05:32:16 AM »
or this :   dfa 100 wr  ,   is this one more flat ,  or does it have a 3d look ?   is that what micro contrast is supposed to do ?   give the 3d look ?   this image looks flat to me,   is it just in taking the photo ?  or is it the lens ?  
this micro contrast stuff has me comfabulasted.  
« Last Edit: January 06, 2016, 05:35:53 AM by lensoreat »

January 07, 2016, 08:43:00 PM
Reply #8

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #8 on: January 07, 2016, 08:43:00 PM »
can a lens have good micro contrast,   but have not good over-all contrast ?  
super-takumar 28/3.5  

January 15, 2016, 06:34:34 AM
Reply #9

Offline lensoreat

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Re: how to know if a lens has good microcontrast ?
« Reply #9 on: January 15, 2016, 06:34:34 AM »
could be ( 'course what do i know ... )  that this nikkor 45mm /2.8  GN   lens has good micro contrast.