A possible answer to varied test results (HVX)

evinsky

Well-known member
I was doing some of my own testing tonight, as I just got my HVX, and at first my Century optics resolution chart was telling me about the same as what Adam Wilt was seeing in his tests. 550 or so LPH/W. I decided to try some still life subjects and some text and it kept baffeling me why text and charts seemed so fuzzy but fine detail seemed to render very well in the objects in the scene. There was an old casette tape with some typewritten text on it and the detail in the black tape seemed good but the type was barely readable. In fact there was type on a price lable in a shadow that was the same size as the type on the tape and it was very clearly readable. That gave me a clue... what if it's not the detail that's the problem but the exposure. What if for some reason the HVX has a problem with high frequency detail above 85-90 IRE? Basically wraparound. There could be a hundred reasons why this happens, I can't speculate, but sure enough, when I upped the shutterspeed to 120 the text on the tape became clear. I don't know exactly what the chart exposure was in the 4(6) way shootout but I bet if the test was redone at a lower exposure the result would have been better. I have yet to try it myself, I'm tired and need to get to bed. I'll try in the morning maybe, and try to capture some stills for you guys too. This shouldn't concern anyone, you very rarely have high frequency detail that much into your highs, unless your shooting charts.
 
evinsky,

that's really a good point!
Go on with your tests and let's know and eventually we will know how to tweak the camera settings and go toward better resolution in very high contrast areas!
The same happens with good SLR photo cameras when trying to resolve fine details at the edge of black objects over white background. Then I realize they are intended to shoot in color and not in black and white.

Piero
 
Well, so far the stills (and my eyes) are having a hard time rendering the same results as the HD-CRT seemed to. So the jury is still out on my theory.
 
So evinsky, when you saw the improvement, it was on the HD-CRT?

You would think frame grabs would show some benefit if what you are seeing on the CRT has improved?

Thanks, Steve
 
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