Originally posted by dlacouture Out-topic, but I just wanted to point out that this argument is moot, as truly equivalent lenses (meaning with the same Fov and DoF) have roughly the same size/weight/price, and that FF even offers some lenses that would be utterly prohibitive in APS-C...
I mean, can you imagine the price of the true equivalent to a 70-200/2.8? This would be a 50-135/1.8 (which would be about the same size and weight as the 70-200/2.8, BTW)???
How much for a 32mm f/1.0, the true equivalent to our 50/1.4???
So, except for the body, FF is not really more expensive or bulky, for truly equivalent DoF/ISO capabilities... And I'm pretty confident that Pentax could issue a FF body roughly the size of a K20, as there is nothing preventing it (maybe SR?).
I always find those arguments a little silly.
First, where did you find that a 50/1.4 on 35mm is equivalent to 32/1.0 on APSC in terms of DOF?
Secondly, DOF is much more complicated than focal length and aperture, I suggest you check TOP
there and
there for a better overview. So calculating equivalent aperture for the same field of view would be valid only at a given distance.
Then, at the end when shallow DOF is not enough DOF? I own a bunch of fast lenses including the FA31ltd, and I can say that I have had prints of shots wide open (wit the 31) where there wasn't enough DOF. Portraits made resonnably close. Bokeh is not the recipe for a good picture, it's what you choose to put in focus that counts. I'm not saying that 50/1.4 (or even 85/1.2 as canon did) are not usefull, but that those lenses are not that usefull
all the time wide open. For movie makers, the 35mm film is roughtly equivalent to APSC, so APSC is their sweet spot here, with bigger formats (like "photo" 35mm) they may have to close aperturetoo much to achieve desired DOF.
Finally, F1.4 is F1.4 no matter what one say, 2 lenses of different focals at the same aperture will gather the same amount of light.
I find this whinning about full frame vey strange, I shoot film 35mm and 6x7, and APSC, and knowing a bit of FF, I can say that all 4 are different formats. The resolution you can get out of a last gen digital SLR is way above what could deliver film on the same area. So you can print bigger and you circle of confusion is smaller, DOF is smaller as a result (this is also an approximation)
Pentax will eventually come out with a FF when they feel it's time to switch, APSC would then let room to little improvement, FF sensors would be mature and relatively cheap, and cameras would be as small as with APSC.
FF is not the holly grail of photography, during film days, it was a compromise adopted by Leica to recycle a format made for movie cameras. The image ratio is less than perfect. And this size of sensor was that perfect, why would Canon continue to release their professional cameras in APSC-H?