Merrill sensored cameras ARE 30MP luminance equivalents to 30MP cameras!

Started Jan 15, 2013 | Discussions thread
xpatUSA Forum Pro • Posts: 10,072
Some re-sampling results

Just for interest, I took DPR's test images for a few Sigma models and my Lumix G1. Reduced them all to SD10 size 2268px wide in PSE 6 bilinear with no post-processing other than re-sampling downward. I sampled the top left slanted square on its right-hand edge using QuickMTF.

Test Area

First figure below is the 10-90% rise of the measure edge, in pixels. Yes, for this purpose, fractional pixels are OK. Second is the lines per picture height (LPH) for a contrast ratio (MTF) of 50%. Third is the MTF at the Nyquist frequency (above which aliasing can occur). The rise is an indication of sharpness, the LPH indicates spatial resolution at a given contrast ratio and the MTF at Nyquist indicates micro-contrast.

Cam. Rise LPH MTF%

SD10 1.41 1066 23

DP1 1.56 982 14

DP2 1.72 984 9

SD1M 1.63 1028 19

DMCG1 1.38 1250 20

Looks like the winner is the Panasonic micro-4/3" although the SD10 at 23% is best on the MTF. At 9%, the DP2 has virtually no micro-contrast.

Before I get jumped, these results from DPR's test images are statistically insignificant and prove very little vis-a-vis sensor performance. Plus, even the slightest application of sharpening or smoothing makes quite a difference to the numbers. No, they are not "real world" image but they were made by experts and were there for the picking. However, I did,  follow the concensus opinion of this forum that only images of the same "size" can be compared.

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Foveon F7X3-C9110

 xpatUSA's gear list:xpatUSA's gear list
Sigma DP2s Panasonic Lumix DMC-G1 Sigma SD10 Sigma SD14 Panasonic Lumix DMC-GH1 +8 more
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