Originally posted by crwl Because sometimes a cheap lens is enough? On full frame even a cheap 50/1.7 is a very usable lens (there are people with D700's who have nothing but a cheap 50mm and that's just fine) - on APS-C, you'd need a 33mm f/1.2 lens to achieve the same kind of depth of field and photographic possibilities. Last time I checked, such a lens doesn't exist.
There is a lot of market for full frame cameras even if you aren't into lenses that cost thousands. Especially if you are into inexpensive and still really good primes. I think Pentaxians, if anyone, should understand that.
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This is an excellent point, and spot on.
I have to admit that I didn't get this at first, either, so I don't hold it against anyone if it seems odd to them.
Shooting less expensive glass on a FF camera seems counterproductive, but keep in mind that just because something is less expensive doesn't mean it's not a good, sharp lens. Consider the Pentax F 50 1.7. One of the sharpest lenses you can put on your Pentax. One of the reasons it's not heralded as much as it deserves optically (aside from being out of production) is that 50mm on aps-c is considered an 'odd' FL, too long for indoor shooting, to short for telephoto, fairly good for traditional portraiture. On a small-bodied, fast-focusing FF Pentax, that lens would be brilliant, and very useful.
I shoot a Nikon $280 20mm f/2.8 AF-D and $109 50 f/1.8 AF-D, and they are both very good lenses, capable of great images. The 20 2.8 would be the equivalent of a 13mm f/2.8, the 50 a 35mm f/1.8 on aps-c. (DOF for the same FOV would make them a 13mm f/1.9 and 35mm f/1, but then we're getting too far into equivalence than most people like to go!
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Bottom line is that a FF camera can make inexpensive lenses very valuable to you, expand your shooting options, and bring some different, fun situations to you.
FF doesn't
have to mean "break the bank".
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