Focal Length, Resolution And Field Of View - SBIG STX Series Operating Manual

36.8 = 4,979 divided by 30 = 166 arcminutes. The table above shows the calculated field of
view in arcminutes for each of the several large format CCDs at various focal lengths. Keep in
mind however that when you vary the CCD field of view you are also varying the field of view
for each pixel and are therefore also affecting the resolution of your system.

1.17. Focal Length, Resolution and Field of View

From the forgoing we see that neither resolution alone, nor field of view alone, are dependent
solely on the number of pixels of a sensor. So when are more pixels better? The key word in the
first sentence is "alone." All else being equal, more pixels will yield a larger field of view
compared to another camera with fewer pixels of the same pixel size. The resolution will be the
same through any optical system, because the size of each pixel remains the same. But more
pixels mean a larger CCD and therefore a larger field of view at the same resolution. So the
question becomes: What is the field of view of a CCD at a given resolution based upon pixel size
and the focal length of your optical system?
The tables on the preceding pages can help you determine this answer. The table below uses the
KAF-16803 CCD as an example:
KAF-16803 with 4096 x 4096 pixels at 9 microns
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