Resolution tests

[Nick Outram]

I have been doing some tests with this resolution chart:

http://www.graphics.cornell.edu/~wes...res-chart.html

-On my Sony HDV-HC1 without Letus I get:

375 vertical and
525 horizontal

with Letus I get:

325 vertical and
475 horizontal

-these tests where done using a tungsten 100w bulb quite close for lighting. The biggest thing that can make the reading innacurate is not having the focus 100% accurate. My sheet was slanted very slightly and this caused an issue at first. When going back to no-Letus I had to decrease the exposure by 1 click to retain no 100% zebra pattern onscreen -this may be 1 stop or slightly more.

My conclusion: The Letus loses about 1 stop of light and a bit over 10% resolution, sharp focusing is critical to maximise resolution. At 1metre with a 50mm f1.4 at max aperture DOF is only a few centimetres...

The vignetting issue reported in a previous post can be solved by zooming just to '2 clicks' in on the HC1 (this is probably about 65mm equiv).


Regards, Nick.

[Holger Leonhard]

could you post some frame grabs ? thanks!