To some of you this may be a simple thing, but I am always surprised to find photograhers who know how many Mega Pixels their cameras are, but are unfamiliar with “pixel dimensions”. Ill shortly have a few posts here that discuss problems and challenges photographers have in relationship to pixel dimensions, but in order to understand those problems, we have to be on the same page as to what Pixel Dimensions themselves are.
Pixel Dimensions are the number of pixels wide and the number of pixels tall of a sensor. They are multiplied to find the total number of pixels on a sensor. Here is an illustration showing how pixel dimensions of a Canon 7D would be determined. Pixel Dimensions can also be found in most camera menus under quality settings. The Largest quality is typically the effective pixel dimension measurement. Additionally, it is important to note that these are referring to “effective pixels”, or pixels which actually represent part of an image. In the case of the 7D (and T1i) there is an additional 1 Million pixels on the sensor, but they have more to do with the construction and operation of the sensor, than the actual recording of an image. These are not typically included in the calculation of pixel dimensions.
Come back tomorrow when we discuss the 8 x 10 and the 8 x 12 dilemma!
Michael, thanks for posting this info. I’ve always wondered. Does image quality degrade by shooting at the full resolution of a camera (i.e. @ 18 MP on the 7D) vs. shooting on the 7D at let’s say Medium size?
Full size typically gives you the best quality in terms of resolution.