edit: ^^ the answer to that question talks about the lens being the same and but not how or why this is the case, and does not answer the question about resultant image,
First of all, to let you know what I understand:
- I am aware that focal length is focal length, and that doesn't change* (that's usually the first line of every answer I've read),
- the difference between full frame and smaller sensors and the effect that the same lens will have on different bodies (with different frame sizes),
- the difference between focal length, crop factor and field of view angle,
- what some are calling "effective" focal length as compared to FOV, cropping and multiplication factor.
(* see second question)
I know this question sounds the same as Shooting 50mm EF vs EF-S and Is an EF 50mm f/1.4 the same as 50mm with an EF-S lens on a Canon 550D? (and a whole heap of others **) but they all seem to go off in slightly different tangents, namely what I will see on different bodies (I don't care about this, I have only one body type), they also cover things such as the effect of (say) an EF-S lens on a FF body (I'm not doing that either).
Put very specifically, here is my question broken into (now) four parts:
Does mounting an EF vs an EF-S lens produce the same results on a camera body that has an APS-C frame size? (my thinking is NO because of the design of the lens and "short back focus" of the EF-S, and the fact that the EF lens produces a picture for a FF sensor and the fact it is further away—when directly comparing 50mm EF and 50mm EF-S—do they have the same field of view, which then leads onto the next question),
(this is probably where my confusion lies, but) aren't the EF-S range of lenses physically closer to the sensor whereby the focal length IS actually shorter?
If EF-S lenses (as a whole unit) are shorter and have a shorter back focus plane, wouldn't that make the FOV wider (ergo not producing the same image)?
- is it the case that Canon have labelled their EF-S 50mm lens as 50mm to the focal plane AS IF the focal plane was a FF 35mm plate at 50mm? Or is the focal distance 50mm to the actual smaller frame? (I think my confusion here is that a 50mm EF lens sits further forward than a 50mm EF-S lens, which to me seems to indicate that one of them isn't 50mm :)
- Why do Full Frame lenses and crop body lenses exhibit the same crop factor when used on a crop body camera?
- What is the difference between EF and EF-S lenses?
- What focal length gives a "normal" field-of-view on APS-C cameras?
- Can I use my APS-C kit lens as a reference for choosing between 50mm or 35mm prime lenses?
- Does my crop sensor camera actually turn my lenses into a longer focal length?
- What is crop factor and how does it relate to focal length?