[Guest]

[quote name='Brightcolours' timestamp='1298026443' post='6213']

Not just that. f1.8 on FF is faster than on APS-C. Equivalent f-value for APS-C is 1.8 / 1.5 = 1.2.

To match the full frame f1.4, you will need on APS-C: f1.4/1.5 = f0.9333(!). Or to match the f1.8 of APS-C on FF you need: f1.8 x 1.5 = f2.7.

So, in short, equivalent are:

50mm f2.8 FF | 35mm f1.8 APS-C

50mm f1.4 FF | 35mm f0.9 APS-C

That is the REAL "in terms of light gathering". A bit bigger than stated, don't you agree (more than 1 stop)?

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Well, I was thinking in terms of EV, where the f-stop is independent of the size of sensor you project the image on. Considering that the light is distributed over a larger area on FF changes the picture of course.



[quote name='Brightcolours' timestamp='1298026443' post='6213']

Correct. Other than that the 24mm designs both from Nikon and from Canon seem to be a bit better than the 35mm designs, especially regarding bokeh. But the 24mm ones are again more expensive too.

The Canon 35mm f2 is a funny small lens, but can deliver surprisingly good results. Something to keep in mind maybe?

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Surely. Looking at all these non-L primes, one may well get to the point where a FF investment becomes cheaper than APS-C. That is, however, also true for Nikon, although Canon has a slightly wider choice of primes.



Any opinions about Canon's 28/1.8, btw? Reviews seem to indicate that one should better avoid that lens.