«

Hi,

I crossposted this question to r.p.digital and the 3 major film
newsgroups since it's related to Depth Of Field vs. sensor (medium) size.

From what I understand, the larger the medium, the longer the focal
length (for a given angle of view) and thus the shallower the Depth of
Field. Clearly some P&S digicams with small sensors have huge DOF, while
full frame 35 mm have much shallow DOF. I never worked with medium or
large format cameras, but I imagine the DOF is even smaller there...

so, you get great detail, sharpness, but you *have to* use a smaller
aperture when you take the photo, otherwise the DOF will be so small;
thus a longer shutter speed. So am I right when I imagine that most
medium/large photos are taken at longer shutter speeds compared to
35mm??? does anyone use medium format for sports photography? just
wondering... thanks!

"chibitul" <> wrote in message
news:ch1b1tul- ...
> Hi,
>
> I crossposted this question to r.p.digital and the 3 major film
> newsgroups since it's related to Depth Of Field vs. sensor (medium) size.
>
> From what I understand, the larger the medium, the longer the focal
> length (for a given angle of view) and thus the shallower the Depth of
> Field. Clearly some P&S digicams with small sensors have huge DOF, while
> full frame 35 mm have much shallow DOF. I never worked with medium or
> large format cameras, but I imagine the DOF is even smaller there...
>
> so, you get great detail, sharpness, but you *have to* use a smaller
> aperture when you take the photo, otherwise the DOF will be so small;
> thus a longer shutter speed. So am I right when I imagine that most
> medium/large photos are taken at longer shutter speeds compared to
> 35mm??? does anyone use medium format for sports photography? just
> wondering... thanks!

I don't do much sports photography, but I have found that my wide angle lens
(I have a 20mm f3.5) has a nice wide depth of field, especially if I stop it
down a little bit. (f 6.3 or f 8.0) When I do this, I can set the focus on
20 or 30 feet in the morning, and not have to focus the lens again all
day! - Everything is sharp from a few feet in front of the camera to
infinity....I think this is how those cheap fixed focus point & shoots
work.........

chibitul wrote:

> Hi,
>
> I crossposted this question to r.p.digital and the 3 major film
> newsgroups since it's related to Depth Of Field vs. sensor (medium) size.
>
> From what I understand, the larger the medium, the longer the focal
> length (for a given angle of view) and thus the shallower the Depth of
> Field. Clearly some P&S digicams with small sensors have huge DOF, while
> full frame 35 mm have much shallow DOF. I never worked with medium or
> large format cameras, but I imagine the DOF is even smaller there...

Yes and some people like shallow DOF

You also have to remember the negatives are enlarged less with the larger
formats so say an 8X10 print made from a 35mm neg, the neg needs to be MUCH
sharper (i.e. smaller coc) than a contact print from an 8X10 negative would
need to have the same apparent DOF at normal viewing distances i.e. to have
the same coc on the final print. So unless you scale up the final image
size in relation to the negative size, the acceptable coc becomes less as
the negative gets larger so the loss of DOF isn't as great as it first
appears but it is there.

>
> so, you get great detail, sharpness, but you *have to* use a smaller
> aperture when you take the photo, otherwise the DOF will be so small;
> thus a longer shutter speed.

Again some shots look better with shallow DOF so the "huge DOF" with
digicams is one thing I don't like about them.. You can almost always stop
down a larger format lens to gain DOF but with the small sensor camera's
there is no way to get shallow DOF.

> So am I right when I imagine that most
> medium/large photos are taken at longer shutter speeds compared to
> 35mm???

Yes that is correct.

>Does anyone use medium format for sports photography?

Not too many, mostly because of the size of the equipment and how large tele
lenses the size needed for sports (a 600 F4 pentax which equals a 300mm in
35mm is a 14 lb lens!)


--

Stacey

chibitul <> wrote in news:ch1b1tul-
:

> Hi,
>
> I crossposted this question to r.p.digital and the 3 major film
> newsgroups since it's related to Depth Of Field vs. sensor (medium)
size.
>
> From what I understand, the larger the medium, the longer the focal
> length (for a given angle of view) and thus the shallower the Depth of
> Field. Clearly some P&S digicams with small sensors have huge DOF,
while
> full frame 35 mm have much shallow DOF. I never worked with medium or
> large format cameras, but I imagine the DOF is even smaller there...

P&S cameras usually have smaller apertures, giving more DOF.

>
> so, you get great detail, sharpness, but you *have to* use a smaller
> aperture when you take the photo, otherwise the DOF will be so small;
> thus a longer shutter speed. So am I right when I imagine that most
> medium/large photos are taken at longer shutter speeds compared to
> 35mm??? does anyone use medium format for sports photography? just
> wondering... thanks!

One factor governing DOF is "circle of least confusion" which increases
as objects are closer or farther from the actual focus point. A larger
format can have a larger circle and still be considered in focus.
Hence, given the same focal length and f-stop, a large format will have
_more_ DOF than a 35mm.
A 150mm lens at f8 focused at 30 feet will have 69.7 inches of depth on
a 35mm or 448.6 inches on 4x5. There is a DOF calculator here:
http://www.outsight.com/hyperfocal.html

chibitul wrote:
> Hi,
>
> I crossposted this question to r.p.digital and the 3 major film
> newsgroups since it's related to Depth Of Field vs. sensor (medium) size.
>
> From what I understand, the larger the medium, the longer the focal
> length (for a given angle of view) and thus the shallower the Depth of
> Field. Clearly some P&S digicams with small sensors have huge DOF, while
> full frame 35 mm have much shallow DOF. I never worked with medium or
> large format cameras, but I imagine the DOF is even smaller there...
>
> so, you get great detail, sharpness, but you *have to* use a smaller
> aperture when you take the photo, otherwise the DOF will be so small;
> thus a longer shutter speed. So am I right when I imagine that most
> medium/large photos are taken at longer shutter speeds compared to
> 35mm??? does anyone use medium format for sports photography? just
> wondering... thanks!

You are basically correct. But it is a bit more complicated. The
total range of usable f-stops is about the same for all formats. You
start at the low end with smaller apertures, but you are less limited by
diffraction at the higher end with very small apertures. This assumes
you are talking about making the same size final print to be viewed in
the same way. So the whole range is shifted towards smaller apertures,
but the size of the usable range remains about the same. The result of
this is not that you get less depth of field but that you have to use
slower shutter speeds for the same depth of field.

One the other hand, there are some other factors involved. Few 35 mm
images can be enlarged to 20 x 25 or beyond, but such prints are fairly
common from 4 x 5 images.

Jeff wrote:
> chibitul <> wrote in news:ch1b1tul-
> :
>
>
>>Hi,
>>
>>I crossposted this question to r.p.digital and the 3 major film
>>newsgroups since it's related to Depth Of Field vs. sensor (medium)
>
> size.
>
>>From what I understand, the larger the medium, the longer the focal
>>length (for a given angle of view) and thus the shallower the Depth of
>>Field. Clearly some P&S digicams with small sensors have huge DOF,
>
> while
>
>>full frame 35 mm have much shallow DOF. I never worked with medium or
>>large format cameras, but I imagine the DOF is even smaller there...
>
>
> P&S cameras usually have smaller apertures, giving more DOF.
>
>
>>so, you get great detail, sharpness, but you *have to* use a smaller
>>aperture when you take the photo, otherwise the DOF will be so small;
>>thus a longer shutter speed. So am I right when I imagine that most
>>medium/large photos are taken at longer shutter speeds compared to
>>35mm??? does anyone use medium format for sports photography? just
>>wondering... thanks!
>
>
> One factor governing DOF is "circle of least confusion" which increases
> as objects are closer or farther from the actual focus point. A larger
> format can have a larger circle and still be considered in focus.
> Hence, given the same focal length and f-stop, a large format will have
> _more_ DOF than a 35mm.
> A 150mm lens at f8 focused at 30 feet will have 69.7 inches of depth on
> a 35mm or 448.6 inches on 4x5. There is a DOF calculator here:
> http://www.outsight.com/hyperfocal.html

What you say is correct, but it ignores the fact that the same focal
length lens will have a different angle of view. A 150 mm lens is a
normal lens for 4 x 5 but quite long for 35 mm.

>
>
>

DOF is controlled primarily by 2 things --
focal length and aperture opening size --
and secondarily, less significantly by
optical design.

With that, a normal lens on 8x10 (300mm) @ f5.6
will have less dof than a 50mm on your 135 camera @ f5.6.

But that's not a disadvantage.
It's a major why people buy "fast" lenses -- to get more control of DOF!
It's what makes classic portraits look so special, with just the eyes in focus.
Can't do that with 35mm unless you go acquire a 1.2 or 1.0 lens.
Even then you don't have movements to manipulate things.

now a little rant, just for fun ...

With 4x5 hand-held, many used flash to compensate.
But 8x10 & larger is generally either long exposure or very good, bright lights.
There have been 5x7 press cameras but never an 8x10 hand-held that I'm
familiar with. (Anyone willing to try?)

Most good 35mm lenses are as sharp or sharper than 4x5 or 8x10 lenses,
but the cost is significant. Having to deal with coma, barrel, and
pincussion distortions, spending a fortune on lenses just to get sharp
snapshots from the best lenses.

I've talked about the Pentax Limited series and how excellent they are
but also how expensive. Yet for the price of one of those lenses you can
get a medium or large format solution that will provide even sharper pictures.
Though not as convenient as 135 systems, good medium or large format will
get the job done better and easier than one might expect. It's why I use
135 for convenience, as it is intended, but medium and large when I want a
really nice picture for the wall.

One would do well to get a Yashica Mat 124G ($100 to $200) or
Rolleiflex 2.8C, D, or E ($300 - $600) and
get really nice pics when they're wanted.

Keep 135 costs under control. Get a nice system and enjoy it.
You can spend a lot of money to get a neg the size of a postage stamp.
You can spend less and get an equivalently sharp larger neg.
Take your pic.

Collin


chibitul <> wrote in message news:<ch1b1tul- >...
> Hi,
>
> I crossposted this question to r.p.digital and the 3 major film
> newsgroups since it's related to Depth Of Field vs. sensor (medium) size.
>
> From what I understand, the larger the medium, the longer the focal
> length (for a given angle of view) and thus the shallower the Depth of
> Field. Clearly some P&S digicams with small sensors have huge DOF, while
> full frame 35 mm have much shallow DOF. I never worked with medium or
> large format cameras, but I imagine the DOF is even smaller there...
>
> so, you get great detail, sharpness, but you *have to* use a smaller
> aperture when you take the photo, otherwise the DOF will be so small;
> thus a longer shutter speed. So am I right when I imagine that most
> medium/large photos are taken at longer shutter speeds compared to
> 35mm??? does anyone use medium format for sports photography? just
> wondering... thanks!

In article < >,
(Collin Brendemuehl) wrote:


> now a little rant, just for fun ...
> With 4x5 hand-held, many used flash to compensate.
> But 8x10 & larger is generally either long exposure or very good, bright lights.
> There have been 5x7 press cameras but never an 8x10 hand-held that I'm
> familiar with. (Anyone willing to try?)

Been done; Look for the "Hobo Camera".

--


website:
http://members.bellatlantic.net/~gblank

In article < >, Collin
Brendemuehl <> writes
>DOF is controlled primarily by 2 things --
>focal length and aperture opening size --
>and secondarily, less significantly by
>optical design.
>
It depends on focal length, aperture and object distance (plus, if you
are going to be picky, final image size).

How do you believe the "optical design" affects DOF? Presumably you mean
the arrangement of lenses chosen as the basis for the computation
(Tessar, Planar, Gauss etc.). I have never seen any suggestion that it
does depend on this (and don't see how it could) but if you know
something to prove it does, this would be interesting.
--
David Littlewood

On 11/17/2003 6:58 AM Gregory W. Blank spake thus:

> In article < >,
> (Collin Brendemuehl) wrote:
>
>> now a little rant, just for fun ...
>> With 4x5 hand-held, many used flash to compensate.
>> But 8x10 & larger is generally either long exposure or very good, bright lights.
>> There have been 5x7 press cameras but never an 8x10 hand-held that I'm
>> familiar with. (Anyone willing to try?)
>
> Been done; Look for the "Hobo Camera".

Like here: http://www.bostick-sullivan.com/Hobo/welcome.htm

Kewl! A handheld 8x10 with built-in vignetting, no focusing (truly "point &
shoot"), that you can literally stand on, and that gives a super-wide view!


--
Any fool can tell the truth, but it requires a man of some sense
to know how to tell a lie well.

- Samuel Butler