I don't get pixel size relative to chipset size. To put it to the simplest context, will i get a bigger field of view from 300d upgrading to a 40d? or a smaller fov? or the same?
arh Paul, you always there when i need help thanks buddy. so that slight increment: 43.2 x 64.8 acrcmin and 44.3 x 66.4 from the 300d, that means the object will be bigger?
Yes the objects will be slightly bigger but your field of view will be slightly smaller. Also your image scale will go from 1.3 to 1 arcsec/pixel. Shame you can't use a FR with your setup, you are basically wasting 1 arcsec/pixel in resolution (in good seeing, more than that normally) that could be used to increase your sensitivity.
I looked at the sensor sizes you quoted. Is there a difference between the actual sensor size and the effective sensor size? This is often quoted in the camera specs. Sometimes part of the edge of the array is not used for imaging. If so then the array sizes may be almost identical.
The only things that determine your field of view are the effective array size and the lens you look through (scope). The number of pixels only changes the resolution not the size of the field.