Same depth of field for digital vs. film

Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

Thanks,
Winston

Yes ...to both parts. But, I don't know the science of it...just the real
world experience. So lets see what those who know the math have to say about
it. DOF is a function of the aperture. The aperture size is not a fixed
size, but a ratio of the sensor size and something else....distance out to
some point in the lens. So F-stop is the ratio and that stays the same even
when the sensor size and length changes. I think I have most of that
approximately almost near right.


"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

Thanks,
Winston

Yes ...to both parts. But, I don't know the science of it...just the real
world experience. So lets see what those who know the math have to say about
it. DOF is a function of the aperture. The aperture size is not a fixed
size, but a ratio of the sensor size and something else....distance out to
some point in the lens. So F-stop is the ratio and that stays the same even
when the sensor size and length changes. I think I have most of that
approximately almost near right.


"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

Thanks,
Winston

"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Yes, of course. There's nothing that could make it different.

Bear in mind however that "depth of field" is not an exact concept. It's a
matter of how much blur you are willing to tolerate. It depends on print
size and what you want your pictures to look like.


Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

For the same print size, yes.

--
Clear skies,

Michael A. Covington
Author, Astrophotography for the Amateur
www.covingtoninnovations.com/astromenu.html

"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Yes, of course. There's nothing that could make it different.

Bear in mind however that "depth of field" is not an exact concept. It's a
matter of how much blur you are willing to tolerate. It depends on print
size and what you want your pictures to look like.


Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

For the same print size, yes.

--
Clear skies,

Michael A. Covington
Author, Astrophotography for the Amateur
www.covingtoninnovations.com/astromenu.html

Winston

IIUC the DOF is a factor of the true focal length of the lens (not the
equivalent) and the acceptable "circle of confusion" which is a measure of
the acceptable sharpness (e.g. what is acceptable to you may not be
acceptable to me and vice versa).

Digital compacts have a major problem in DOF being extremely wide due to the
small sensors and very short focal lengths required by these sensors. The
wide angle end is often in the range from 5.5 to 8 mm focal length (probably
equivalent to 34 to 40 mm with multiplication factors of 5 to 7) and whilst
the minute sensor requires a much smaller circle of confusion the DOF is
often incredible (often 1m to inf at f4).

Changing from one film to a different one can have an effect on sharpness in
that technology so I suppose that technically the pitch of the pixels and
the colour of the light may have some effect, but in real world terms on any
given camera the DOF (once you have defined what is acceptable to you) is
defined by the focal length.

Peter
--
Peter & Elizabeth Corser
Leighton Buzzard
Beds UK
"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

Thanks,
Winston

Winston

IIUC the DOF is a factor of the true focal length of the lens (not the
equivalent) and the acceptable "circle of confusion" which is a measure of
the acceptable sharpness (e.g. what is acceptable to you may not be
acceptable to me and vice versa).

Digital compacts have a major problem in DOF being extremely wide due to the
small sensors and very short focal lengths required by these sensors. The
wide angle end is often in the range from 5.5 to 8 mm focal length (probably
equivalent to 34 to 40 mm with multiplication factors of 5 to 7) and whilst
the minute sensor requires a much smaller circle of confusion the DOF is
often incredible (often 1m to inf at f4).

Changing from one film to a different one can have an effect on sharpness in
that technology so I suppose that technically the pitch of the pixels and
the colour of the light may have some effect, but in real world terms on any
given camera the DOF (once you have defined what is acceptable to you) is
defined by the focal length.

Peter
--
Peter & Elizabeth Corser
Leighton Buzzard
Beds UK
"Winston" wrote in message
om...
Will a digital camera with the same sized sensor as a 35mm film
camera's 24 x 36mm format have the EXACT same depth of field as that
film camera, given everything else is equal, lens, aperture, distance,
etc.

Along the same lines, does a smaller sensor automatically mean it will
have more DOF than one that is slightly larger. In other words will a
lens multiplication factor that is lower (say, 1.1) have less DOF that
one that is higher (say 1.6)?

Thanks,
Winston

Peter Corser wrote:
[]
Digital compacts have a major problem in DOF being extremely wide due
to the small sensors and very short focal lengths required by these
sensors.

... either a major problem, or a major plus point for compacts depending on
your needs.

David

Peter Corser wrote:
[]
Digital compacts have a major problem in DOF being extremely wide due
to the small sensors and very short focal lengths required by these
sensors.

... either a major problem, or a major plus point for compacts depending on
your needs.

David

Does it matter?

Why assume film DOF has superior qualities?

Aerticus