Originally posted by BigMackCam But if you're merely looking to achieve more out-of-focus backgrounds, I'd encourage you to be more aware of, and creative with, your subject-to-background distances. You have a huge amount of control in throwing backgrounds out of focus by positioning your subject appropriately.
This ^ ^ ^
Most of my bokeh shots with the K-3 have been done at 50mm to 135mm and at f/2 or narrower with a surprising number being at f/4 and f/5.6.
As for FF vs APS-C...as noted above, with magnification being equal (same framing), there is no difference in DOF between the two formats for a given
absolute aperture (not the same as f/number). As a result of that bit in the parentheses and in practice, available DOF does tend to be more limited as frame size increases. Before one gets too excited, I would caution that is not really a good thing. Imagine if you would a face shot (portrait) at f/8 where only the subject's eyelash is in acceptable focus. Welcome to the world of 4x5 and larger formats. Even with 35mm FF, the challenge is to maintain adequate DOF so that one's subject does not fade to blur. At 50mm and f/1.4 at head portrait distances on FF, such is a fantasy.
For subject isolation and pop, background blur is useful. So is difference in contrast, texture, and color and light values. There is nothing fail-safe or even particularly useful about razor-thin DOF.
Originally posted by clackers It's a myth, Wasp.
I was not intending the above to be a direct contradiction of your statement. What you are saying is true, but with the qualifier of aperture. DOF is a complex topic and difficult to discuss without either math or comparison images. I have comparison images somewhere that I did in about 2009 for DOF of equivalent crops at different focal lengths that illustrate nicely. As I noted above and other comments have called out, there is nothing magic or even particularly useful about limited DOF. In my opinion, it is a pain.
Steve