Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-22-2013, 07:39 AM   #1
Senior Member




Join Date: May 2011
Location: Sweden
Posts: 158
How to test micro contrast?

Ok I dont really know what micro contrast is, but Ive heard it can make a picture pop. Thats why I bought an FA43. The problem is I have the F50/1.7 too and they are both good. I cant find anything that proves the FA43 better. Anyone know how to test them to see the FA43 power? what to shoot to compare micro contrast etc.?

09-22-2013, 10:29 AM   #2
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,415
A few definitions:

"Macro" contrast = the full range of dark-to-light within the frame or within a range of brightness values (in film photography language, the steepness of the "characteristic curve" within a given range)

"Micro" contrast = dark-to-light transitions on a small scale within the elements of the frame.

In theory, a lens that provides good rendering of micro contrast should give an image "pop" that other lenses may fail to do. I don't know that there is a test for micro-contrast. I am not even sure there is good agreement on what it is. I personally prefer the term "pixie dust".

Your FA 43 has been granted a liberal dose of "pixie dust" and with experience you will learn how to best leverage its characteristics.


Steve
09-22-2013, 01:46 PM - 1 Like   #3
Pentaxian




Join Date: Nov 2011
Photos: Gallery | Albums
Posts: 3,735
QuoteOriginally posted by stevebrot Quote
I don't know that there is a test for micro-contrast. I am not even sure there is good agreement on what it is.
One indicator is given by the MTF curves at 40lp/mm
If they hold up above 50%, you can expect good microcontrast.

Here's an example for the Zeiss Makro-Planar 50/2,
the bottom curves in the graph.
(The upper curves are for 10 and 20 lp/mm.)
The horizontal axis measures mm away from the center of the image.
The vertical axis measures contrast in %.
Attached Images
 
09-22-2013, 03:17 PM   #4
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,415
QuoteOriginally posted by lytrytyr Quote
One indicator is given by the MTF curves at 40lp/mm
If they hold up above 50%, you can expect good microcontrast.

Here's an example for the Zeiss Makro-Planar 50/2,
the bottom curves in the graph.
(The upper curves are for 10 and 20 lp/mm.)
The horizontal axis measures mm away from the center of the image.
The vertical axis measures contrast in %.
Well, that makes sense.


Steve

09-22-2013, 04:01 PM   #5
Pentaxian
JinDesu's Avatar

Join Date: Jun 2011
Location: New York City
Photos: Gallery
Posts: 5,626
QuoteOriginally posted by lytrytyr Quote
One indicator is given by the MTF curves at 40lp/mm
If they hold up above 50%, you can expect good microcontrast.

Here's an example for the Zeiss Makro-Planar 50/2,
the bottom curves in the graph.
(The upper curves are for 10 and 20 lp/mm.)
The horizontal axis measures mm away from the center of the image.
The vertical axis measures contrast in %.
You have singlehandedly explained MTF charts to me when I couldn't figure out why there were so many lines before. Thank you.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
contrast, fa43, k-mount, pentax lens, slr lens, test
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How to test second hand AF lens? MSL Pentax SLR Lens Discussion 4 09-21-2013 11:04 PM
Micro focus How to ? marquis1955 Troubleshooting and Beginner Help 6 08-20-2013 05:23 PM
New K5! How to test for stains and other potential ills? Antifreez Pentax K-5 18 11-08-2011 11:30 AM
K5 - How do I access "Custom Image" to change sharpness/saturation/contrast, etc ? Feudal1 Troubleshooting and Beginner Help 3 11-03-2010 06:38 AM
i've actually learned how to use LiveView + contrast AF "properly"... RolloR Pentax DSLR Discussion 27 09-28-2010 08:14 AM



All times are GMT -7. The time now is 02:28 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top