Here is a roughly done (sorry) comparison of the aliasing from an EX1R at the bottom and my F3 at the top. The F3 had a Nikon 18-135mm zoom, both cameras were set to default settings, 25P. The F3 clearly shows a lot more chroma aliasing appearing as coloured moire rings in both the horizontal, vertical and diagonal axis. The EX1R is not alias free. The chroma aliasing from the F3 is not entirely unexpected as it has a bayer sensor and there is always a trade off between luma resolution and chroma resolution and the point where you set the optical low pass filter. Frankly I find this performance a little disappointing. More real world test are needed to see how much of a problem this is (or is not). To put it in to some perspective the F35 aliases pretty badly too, but that camera is well known for producing beautiful images. I hope I’m being over critical of this particular aspect of the F3’s performance, because in every other respect I think the camera is fantastic.
UPDATE: I’ve taken a look at the MTF curves for the F3 and they are quite revealing showing that an OLPF is in use which is giving an MTF50 of around 800 LW/PH V and 950 LW/PH H. This is not quite as high as an EX1 and are quite reasonable figures for a 1920×1080 camcorder. This suggests that the aliasing is largely limited to the chroma sampling of the sensor. As this is a bayer (or similar) type sensor the chroma is sampled at a reduced rate compare to luma, which is why coloured moire is not entirely unusual.
Tests performed with a Tokina ATX-Pro 28-70mm lens at 25P
Feeling a bit better about my F3 now 🙂
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