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USAF 1951 Resolution Chart and Table of Constants

USAF 1951 Resolution Chart and Table of Constants

I find it interesting that few if any current web links provide ALL the information necessary to use these charts.

Using this table of values linked here which shows the constants for the Groups and Elements of the Line Pairs Chart,
the forumula is 8121 / (D x LPM) where D is the distance to your target measured in inches and LPM is the value from the Constants.
The constants are the actual number of line pairs per mm for the mimimum you can see.
For instance a 10x binocular used at a distance of 125 feet that can see line pairs in Group-1, Element2 has a value of 0.561. Therefore it's resolution is 8121/(125x12x0.561) = 9.65 arcseconds. Line Pairs Resolution CANNOT be directly compared to point source resolution. See the forum discussion.

It is extremely important to have the target sized properly. See the discussion in the forum thread.
Binocular Resolution Testing Using 1951 USAF Line Pair Charts
In addition to test results for about a dozen binoculars, this thread shows some comparative results for a very good semi-apo 80mm telescope. Also included is a discussion on how to use the charts and links to web access for the charts and tables.

It is extremely important that the chart be exactly sized. As a check, the three bars and two spaces in Group-2 Element 1 should measure exactly 10mmx10mm. Both the sets of bars in G -2 E2 and the solid black square top center should measure 9mmx9mm.

This page was originally accessed from http://medfmt.8k.com...resolution.html Lens Resolution Testing by Robert Monaghan
which has posted the following notation along with the information
[My understanding is that the USAF chart etc. is in the public domain as it is a government produced chart and related documentation...]


    Link broken :-(
    probably no hope of ever re-establishing these decade old links.

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