On Thu, 22 Mar 2012 01:05:43 -0700, "anorton"
wrote:


"Ed Huntress" wrote in message
.. .
On Wed, 21 Mar 2012 23:12:36 -0400, "J. Clarke"
wrote:

In article , huntres23
says...

On Wed, 21 Mar 2012 19:16:14 -0400, Wes
wrote:

wrote:

sorry, I disagree, you would not be able to do the same quality with
a 10Mp
camera, take those shots with the 4x5 and a 10mp put them side by
side, you
would not have that depth

Most digicams don't work well with high numerical f stops. Thus,
properly lighted, a 4x5
camera will have greater depth of field than a digicam. It was one of
the first things I
learned when I went with compact digital cameras.

Wes, as a guy with two 4x5 cameras and 15 magazine covers behind me,
you'll have one hell of a time getting a lot of depth of field with a
4x5. When I've had to, it's been f/64 and use the swings and tilts.
I've also used an 8x10 Calumet for some trade-show Translites for
Casio. That sucker really shows you how depth of field disappears with
large sheet film.

When someone talks about "depth" in photography, I think of the things
that give the impression of actual, physical depth. Others have
pointed to expert lighting, and that's a big part of it. Kodachrome
also has (had) a slight inherent edge effect, which gives the
impression of more depth. And people like me, who made his living for
a while silver-masking Kodachrome slides, can tell you about another
edge effect. Or you can use Unsharp Masking in Photoshop and get
almost the same thing.

Anyway, it's there. But it's probably all lost in conversion to a
moderate-res digital copy for the Web. You'd have to blow it up and
look really close.

Dunno where the killfile resident gets the idea that digital cameras
don't work well at high f stops. My 30d works very nicely at any f stop
that any of my lenses can achieve. On the other hand, the performance
of the lenses is compromised by diffraction at small apertures, but that
affects any type of sensor.

But if you want a mighty ****load of depth of field, go for one of the
little point-and-shoots.

My cell phone does well at that, too. d8-)

I sent Wes a photo I shot with my crappy cell phone (a dumb phone, not
a smart one) a couple of years ago. It has even sharpness from the
right pectoral fin of the bluefish all the way to Staten Island.

It must have a teeny little sensor but a little unsharp masking makes
the fish pop pretty well.

--
Ed Huntress

As a designer of lenses, I hope I can give some insight into why a point and
shoot almost always has larger DOF than a 4X5. The DOF (in most
photographic situations) is proportional to the focal length divided by the
F/#, in other words the inverse of the entrance pupil diameter. If the
point and shoot and 4X5 have the same field of view, the small sensor in the
point & shoot would need a lens focal length that is perhaps 1/20 as long.
To match the point and shoot DOF at F/5, the 4X5 would have to be stopped
down to F/100

I have seen some great shots taken with tiny f.l. endoscope lenses that show
sharply focused insects in the foreground and large trees in the distance.

It is also true, BTW, that the small pixels in small digital sensors require
some fairly fast f/#s to make the diffraction limit not noticeable. The
iPhone 4S camera, for example, is F/2.4 and has 1.4 micron pixels.

Thanks. A normal lens for that small sensor sure does have some depth
of field. My Minox III does the same thing -- 9.5 mm film.
\
At the other end, I've used a 310 mm normal lens for 8 x 10, and it
was f/64, f/128, or nothing. g

--
Ed Huntress