Video Accessories Misc
- Written by John E. Johnson, Jr.
- Published on 01 June 2010
On the Bench
With the lens set to wide angle, falloff at the corners, where it was the worst, was only 0.121 f/stops.
Looking at this in a different way, with lighter and darker gray gradients, it is easier to see the falloff, and the fact that the area of the image with the most exposure is shifted towards the top and to the right.
In telephoto, the corners were also the worst, but still, the falloff was only 0.288 f/stops
And here is the image with gray gradients for easier viewing. Notice that in this case, the area of greatest exposure is towards the bottom and in the middle.
The MTF50 (resolution) for the HM550 was 1075 LW/PH, which is very close to the 1080 lines of the high definition format. The MTF50P was 0.497 Cycles/Pixel, where 0.5 Cycles/Pixel is the theoretical limit. It can actually go over this number if there is a lot of image sharpening. The large area under the bottom curve above 0.5 cycles/pixel (colored light blue) suggests that this camera does not have an anti-aliasing filter. This is a major factor in the camera's very sharp image quality. The downside is that for certain specific items in a scene, i.e., where there are repeating patterns close together, such as fabric (be careful about getting too close to the bride's dress !!), you may see a moiré pattern.
Chromatic aberration measured at 0.454 pixels.
Measured noise levels were significantly lower than with the HM400. This is due to the mirror behind the sensor that increases the amount of light passing through the sensor pixels.
At wide angle, there was 2.16% barrel distortion (the lines bow outward). This is normal for a zoom lens, and we will see how this compares with other cameras in future reviews. (Click on the photo to see the full size version.)
Color analysis revealed a tendency for over-saturation as indicated by the fact that the circles (the camera) for the various colors are more towards the periphery than the squares (color reference). The exception is in the yellow, where there is a bit of under-saturation.
The Q-60 color chart test resulted in a bit of underexposure, as shown by the black rectangles not being distinguishable between 19 and 22.