Why no Depth-of-Field priority mode in cameras.

All SLR cameras have Aperture priority mode. However this requires you to know in your head how much depth of field a given aperture has at a given focal length.

Why don't cameras have a depth-of-field priority mode instead of, or in addition to Aperture-priority mode?

You would know you are photographing one person, and you want say, 3 feet depth of field and dial that in. Say the person is running toward you, and you zoom out, the camera would automatically change the aperture to compensate and give you the same effect.

Why can't camera's be "results oriented" rather than requiring the photographer to make unnecessary mental calculations

Another example is auto-iso. Only Nikon allows you to specify the result that you want "minimum shutter speed" rather than having to change the ISO yourself or following a preset auto-iso algorithm.

Even in the age of DSLRs, it seems there is much untapped automation potential.

Well I don't use the program modes but I'm thinking my 30d has one that weighs toward a narrow DOF, maybe not. In any case it does have a DOF preview button which I think most DSLR along with SLR's have. At least most Canon's and I believe Nikon's. I don't do a lot of mental calculations, just know at the wide end it's going to be narrow and I'm shooting landscapes or something I want everything in focus I better be at f9 or higher. I do miss the scales that use to be on the lens which let you set the hyper-focal length.
--
Doug

http://douginoviedo.smugmug.com/

I've thought about a depth-of-field calculation system in DSLRs. After all, the camera usually has all the data required to make the calculation: lens focal length, aperture and focus distance. I'm not sure DOF priority is practical though.

Imagine a user with an 18-200mm lens on an APS-C sensor SLR. If the user wanted the camera to maintain a 1 metre DOF at 18mm, that should be quite easy even at close range with reasonably wide apertures. Imagine now that the user zooms to a 200mm focal length. At 200mm, the depth of field is liable to become very shallow, forcing the camera to select a very small aperture, like f/32. That will make the shutter speed plummet, which is exactly the opposite of what you want when shooting at longer focal lengths.

It could be argued that shutter speed doesn't matter when the camera is tripod mounted, but I would counter that argument by saying that the photographer is likely to have the time to make considered adjustments to achieve a specific result, if shooting from a tripod.

So yes, I think an indication of depth of field (nearest and farthest distances in focus) on the LCD display is easy to implement, and would be extremely useful. I'd go so far as to say that an "Auto Hyperfocal" one-touch button would be very well received. I just don't think that a DOF-priority implementation is the right way to go about it.

Amy

LongZoom said:

All SLR cameras have Aperture priority mode. However this requires
you to know in your head how much depth of field a given aperture has
at a given focal length.

Why don't cameras have a depth-of-field priority mode instead of, or
in addition to Aperture-priority mode?

Click to expand...

Minolta used to have cards for its xi-series cameras that did this sort of thing. Portrait card would optimize DOF based on focal length and FOV, assuming it was a head shot, half-torso, full-length, etc. Other cards were used for landscape or other deep DOF applications.

I read that the Program mode on the newer cameras used the same "Portrait" logic. Although I can't confirm it, it seems to be true.

LongZoom said:

You would know you are photographing one person, and you want say, 3
feet depth of field and dial that in. Say the person is running
toward you, and you zoom out, the camera would automatically change
the aperture to compensate and give you the same effect.

Why can't camera's be "results oriented" rather than requiring the
photographer to make unnecessary mental calculations

Click to expand...

Because other things are a bit more critical. Like shutter speed, You can live with slower shutter speeds at shorter focal lengths. Better a sharp shot with wrong DOF than a blurry shot, wouldn't you agree?

LongZoom said:

Another example is auto-iso. Only Nikon allows you to specify the
result that you want "minimum shutter speed" rather than having to
change the ISO yourself or following a preset auto-iso algorithm.

Even in the age of DSLRs, it seems there is much untapped automation
potential.

Click to expand...

Some would argue this is best left for the P&S crowd. ;-)

Although I WOULD like more auto-ISO control myself.

Greg

LongZoom said:

All SLR cameras have Aperture priority mode. However this requires
you to know in your head how much depth of field a given aperture has
at a given focal length.

Why don't cameras have a depth-of-field priority mode instead of, or
in addition to Aperture-priority mode?

You would know you are photographing one person, and you want say, 3
feet depth of field and dial that in. Say the person is running
toward you, and you zoom out, the camera would automatically change
the aperture to compensate and give you the same effect.

Why can't camera's be "results oriented" rather than requiring the
photographer to make unnecessary mental calculations

Another example is auto-iso. Only Nikon allows you to specify the
result that you want "minimum shutter speed" rather than having to
change the ISO yourself or following a preset auto-iso algorithm.

Even in the age of DSLRs, it seems there is much untapped automation
potential.

Click to expand...

in more complex EXIF readers my Olympus gives you the focus point from the AF
from that the EXIF describes the dof, but it isnt displayed 'in camera'

i think it would be good if it provided me with the dof with both far and near focus, and its likely the sort of thing that could be massaged into the LCD via firmware

given that, i agree it would have it uses and would use it if i had it

--
Riley

I'd give my right arm to be ambidextrous (just)

Gregory King said:

Some would argue this is best left for the P&S crowd. ;-)

Click to expand...

now be brave Greg, isnt that what you are saying

i think if you had the terms of near and far focus given, you could use that inf to advantage

Gregory King said:

Although I WOULD like more auto-ISO control myself.

Click to expand...

i had a chat with an M8 wedding photog who uses constant shutter speed set and constant aperture. He wheels the iso control to get the right exposure. I found his technique to be very clever, which got me to thinking. I do something similar to control the flash lit depth with interiors.

Although i have auto iso 100-3200 i think i would prefer an iso control wheel say at the rewind position on the top deck. Not sure but i think Minolta digitals had such a thing, and i havent checked if SONY carried this over.

--
Riley

I'd give my right arm to be ambidextrous (just)

Interestingly, the old Canon EOS 1000F (film) that I was given a while ago has just such a feature. However, it's slow and clunky to implement (set it to DEP mode, focus on the near point you want in focus, 1/2 press the shutter, repeat for the far point, then take the pic, IIRC. And the camera will do its limited best to accomodate your wishes), so I guess that it probably wasn't used by too many shooters, especially seeing as the camera was aimed at the amateur crowd, who seem to have trouble with anything beyond 'point, shoot'. And the pros, of course, already know all that stuff, so what use is it to them?

A little knowledge sometimes makes the difference between a mere shutterbug and a photographer. Automation only makes for better photography when the user knows and understands the medium and his tools, and only uses the auto bits to make his job easier, not to do it for him.

--
Rob

----------------------------------------------------------------------------

Everyone, everywhere, has to do everything for a first time. There is no shame in failure, only in failure to try.

It's been about in the Canon range for a long time now.

Hi,

It would be useful but I can't help thinking that a bit of card for the favourite lens would do the trick with a few figures scribbled on it. Trouble is we used to get that info on the lens' barrel, once upon a time (film days), and so picking the right DoF we wanted was simple but then you found the shutter speed would be a bit silly and the only answer was to swop the film back to gain high speed or (expensive) swop the film in mid-roll.

But they fill the camera's CPU up with nonsense that tells us to use "portrait" mode for portraits and landscape, well, you get the picture. Pity they don't give us a couple of pages in the CPU for notes like DoF. Then we could load our notes into the thing and at least look it up quickly. Ditto hyperfocal distances etc. But a "DoF" mode and an "H" mode ought to be feasible.

Some of the things we abandoned with film keep coming back to haunt us, don't they? I miss the DoF guide on lenses, ERC's and some of my older cameras had a pocket in the back of the case for a bit of card that you could scribble notes on. Here's a picture to show it with an elderly camera:



Very useful at times.

Regards, David

But that's not as good as the EOS5's version where you put the centre af point on a near object, press the shutter to gain af lock, then choose a far object and lock the af. Re-compose and the camera works out the aperture for the dof to cover all points in between.

This was more useful than A-Dep where the objects in question have to be covered by the af points in one go.
When I got my D60 I tried the A-Dep mode and wondered if it was faulty.

I often wonder why Canon seem to simplify features or remove them completely when they have already been proven to work. I doubt it's down to cost as the R&D has already been done.

Eye control dof preview was brilliant !!

--
It's an L of a life, this photography lark

http://www.freelancephotographic.net/

LongZoom said:

All SLR cameras have Aperture priority mode. However this requires
you to know in your head how much depth of field a given aperture has
at a given focal length.

Why don't cameras have a depth-of-field priority mode instead of, or
in addition to Aperture-priority mode?

Click to expand...

My 1992 architechture Canon EOS A2 has "DEP" (depth of filed) mode that is set automatically once the photographer sets the parameters.

LongZoom said:

You would know you are photographing one person, and you want say, 3
feet depth of field and dial that in. Say the person is running
toward you, and you zoom out, the camera would automatically change
the aperture to compensate and give you the same effect.

Why can't camera's be "results oriented" rather than requiring the
photographer to make unnecessary mental calculations

Another example is auto-iso. Only Nikon

Click to expand...

Olympus DSLRs also.

LongZoom said:

allows you to specify the
result that you want

Click to expand...

Olympus' auto ISO does.

"minimum shutter speed" rather than having to

LongZoom said:

change the ISO yourself or following a preset auto-iso algorithm.

Even in the age of DSLRs, it seems there is much untapped automation
potential.

Click to expand...

You will have to "look outside the box" for some of the auto gimmicks you want.

Rriley wrote:
snip

Rriley said:

i had a chat with an M8 wedding photog who uses constant shutter
speed set and constant aperture. He wheels the iso control to get the
right exposure. I found his technique to be very clever, which got me
to thinking. I do something similar to control the flash lit depth
with interiors.

Click to expand...

the M8 does not have an ISO control wheel ...changing ISO requires depressing the Set button, selecting ISO with another depression of the Set button, using the selection wheel to choose the ISO value desired and then depressing the Set button again to make the selection

I find this procedure far more complicated than changing the aperture (done manually on the lens barrel) or adjusting the exposure wheel which is quite simple to do without removing your finger from the shutter release or raising your eye from the viewfinder
--
--
pbase & dpreview supporter
DPR forum member since 5/2001
http://www.pbase.com/artichoke

Artichoke said:

Artichoke said:

i had a chat with an M8 wedding photog who uses constant shutter
speed set and constant aperture. He wheels the iso control to get the
right exposure. I found his technique to be very clever, which got me
to thinking. I do something similar to control the flash lit depth
with interiors.

Click to expand...

the M8 does not have an ISO control wheel ...changing ISO requires
depressing the Set button, selecting ISO with another depression of
the Set button, using the selection wheel to choose the ISO value
desired and then depressing the Set button again to make the selection

Click to expand...

like i said "Although i have auto iso 100-3200 i think i would prefer an iso control wheel say at the rewind position on the top deck"

Artichoke said:

I find this procedure far more complicated than changing the aperture
(done manually on the lens barrel) or adjusting the exposure wheel
which is quite simple to do without removing your finger from the
shutter release or raising your eye from the viewfinder

Click to expand...

and that will alter qualities of the image you may prefer to keep, and particularly for RF photography, control over dof

an iso control wheel would allow both kinds of music, that cant be a bad thing
--
Riley

I'd give my right arm to be ambidextrous (just)

Rriley wrote:
snip

Rriley said:

an iso control wheel would allow both kinds of music, that cant be a
bad thing

Click to expand...

it would be a welcome addition for any camera

what I commented upon was what you reported the M8 wedding photographer to have said

I wish the M8 had such a simple ISO control & smaller steps between ISO options would be helpful as well
--
--
pbase & dpreview supporter
DPR forum member since 5/2001
http://www.pbase.com/artichoke

LongZoom said:

Why don't cameras have a depth-of-field priority mode instead of, or
in addition to Aperture-priority mode?

Click to expand...

Interesting idea for a feature. I "have it in my head" already being an "old dog", but it could speed up landscape shooting, might be useful in say, rapidly changing light conditions.

If i remember correctly, it is essentially a formula that used to often come with a lense (on paper), called a hyperfocal distance table. I think you can find them in various forms on the web. Goggle " hyperfocal distance table ". Now, of course, a variable also is sensor size, but that would be fixed per camera anyway. Since it can be reduced to a look-up table, should be not too difficult to put in the firmware?

--
Life is short. I try to ignore impolite comments, trolls, and posers.

Artichoke said:

Artichoke said:

an iso control wheel would allow both kinds of music, that cant be a
bad thing

Click to expand...

it would be a welcome addition for any camera
what I commented upon was what you reported the M8 wedding
photographer to have said

Click to expand...

well apologies then
"He wheels the iso control"

is a construct of my own invention perhaps from my own habits. and is less important than the idea or use of iso in this function. That wouldnt have been available in the film era

Artichoke said:

I wish the M8 had such a simple ISO control & smaller steps between
ISO options would be helpful as well
--
--
pbase & dpreview supporter
DPR forum member since 5/2001
http://www.pbase.com/artichoke

Click to expand...

--
Riley

I'd give my right arm to be ambidextrous (just)

Gregory King said:

Although I WOULD like more auto-ISO control myself.

Click to expand...

Pentax has a pretty neat implemantation of ISO modes on the K10D and K20D.

Sv mode - Sensitivity priority mode. With one control wheel you can select the ISO you want, camera calculates shutterspeed and aperture (Program mode like). The second wheel lets you deviate from the camera selection, while maintaining correct exposure. Green button returns you to camera's selection.

TAv mode - Shutter & Aperture Priority mode. One control wheel selects Shutter, other wheel aperture. Camera selects required ISO (upper and lower limits are selectable separately) Green button again gives camera's selection.
--
Regards -x- Ben

N i k o n 5 7 0 0
P e n t a x K 1 0 0 D
P e n t a x K 1 0 D
http://bawfotos.wtrs.nl/

The best proof intelligent life in space exists is that they have never tried to contact us.

morninglight said:

If i remember correctly, it is essentially a formula that used to
often come with a lense (on paper), called a hyperfocal distance
table. I think you can find them in various forms on the web. Goggle
" hyperfocal distance table ". Now, of course, a variable also is
sensor size, but that would be fixed per camera anyway. Since it can
be reduced to a look-up table, should be not too difficult to put in
the firmware?

Click to expand...

Sensor size isn't a factor in DOF calculations. All you need is (actual,) focal length, aperture, and focussed distance. These variables are available to the camera so calculating DOF shouldn't be a problem. Depending on your printing and viewing requirements you have to decide on a value for the Circle of Confusion.
--
Regards -x- Ben

N i k o n 5 7 0 0
P e n t a x K 1 0 0 D
P e n t a x K 1 0 D
http://bawfotos.wtrs.nl/

The best proof intelligent life in space exists is that they have never tried to contact us.

baw said:

Sensor size isn't a factor in DOF calculations.
...Circle of Confusion.

Click to expand...

Perhaps I stated it less than exactly. The aptly named Circle of Confusion is part of the formula (and depends on sensor size, of film format size).
Formula is at bottom of this calculator page.

http://www.dofmaster.com/charts.html

--
Life is short. I try to ignore impolite comments, trolls, and posers.

morninglight said:

morninglight said:

Sensor size isn't a factor in DOF calculations.
...Circle of Confusion.

Click to expand...

Perhaps I stated it less than exactly. The aptly named Circle of
Confusion

Click to expand...

is correctly named the "circle of MINIMUM confusion"

morninglight said:

is part of the formula (and depends on sensor size, of film format size).
Formula is at bottom of this calculator page.

http://www.dofmaster.com/charts.html

Click to expand...