Originally posted by Art Vandelay II There's a reason I chose not to use the term bokeh. I didn't want to get started on another anti-bokeh thread (they are becoming quite common these days). When I mentioned image quality I meant dynamic range, noise control, greater resolutions, and yes the versatility DOF control gives you. I rarely ever use tons of shallow DOF myself, but a slight background blur + good composition can give a photo a slight 3D look unachievable with small sensors.
If someone can explain to me why a street portrait like this one would be better with a sharp background then I'm all ears:
Untitled | Flickr - Photo Sharing!
Shallow DOF shouldn't be a crutch for poor composition, but it is a wonderful tool to have when you need it (such as to blur out an unwanted person/object from a background).
The problem is you are confusing between bokeh and DOF, and expressing a bokeh requirement ("soft blurry backgrounds") as a DOF requirement.
bokeh and DOF are different concepts. DOF is about how much a picture is in focus vs out of focus. bokeh is the quality of the out of focus rendition.
It is possible for a lens with good bokeh at f8 to give a much "nicer" picture than a lens with poor bokeh at f4 or even f2.
The picture you linked to could potentially have been rendered by a lens at f8 - it all depends on the the relative distance between photographer and subject, and how well the lens render bokeh. Some lenses will "exaggerate" bokeh, some play it down - it depends on the lens design.
So I am not willing to assume that the Q will not be able to render bokeh well - it all depends on the lens design and Pentax had 5 years to play with the design.
As for the Q being a "high DOF" camera - with all due respect I would caution against making naive assumptions based on sensor size which a few posters seem to be doing.
As I've mentioned before, DOF depends on the circle of confusion (CoC), not sensor size. CoC is a subjective measure, not objective, and depends on many things.
A lot of DOF calculators on the Internet assume CoC = d/1730 (the Zeiss formula) but this formula is quite naive. The CoC actually depends on interpixel spacing and the effective width of each pixel - Pentax has not yet given us this information so we don't know whether the Zeiss formula is a good approximation or not.
Secondly, some people are using a full frame DSLR as a frame of reference (CoC=0.025). However, I would argue a 35mm film camera is a better frame of reference (typical CoC = 0.030-0.035)
So, even if we assume the Zeiss formula is applicable to the Q (and I have reasons to suspect it doesn't) the Q with the standard prime is not equivalent to a full frame standard prime at f11, but more like f8, and potentially lower.
And there is every possibility Pentax may have tweaked the Q lens design for shallower DOF, so it's quite possible the "equivalency" is f4-f8.
I typically shoot on my K-5 with FA43 at f4-f8, so it's entirely possible that the Q will be roughly equivalent from a DOF perspective.
Note - this is all speculation on my part, but it's based on reasonable assumptions, unlike some of the rampant speculation by armchair experts on this forum.
The real test is when we get to play with a real camera and take real pictures. Until then, I maintain - speculation about the image quality and DOF of the Q is just speculation.