DSLR that adjusts shutter speed w/ focal length?

Do any DSLRs offer a mode to auto-adjust the shutter speed proportionate
to the focal length? (i.e., if I zoom out to 2x the FOV, cut the
shutter speed by 1/2 and open the aperture by 2x)

When shooting motorsports, the ideal shutter speed is a balance between
freezing the subject and conveying motion (e.g., blurred tires or panned
background). Not a problem when using a fixed lens, but a problem if
zooming in/out. (i.e., 1/2000 freezes more at 70mm than at 200mm).

Do models like 1DsII or D2Xs offer such a feature? If so, what's it called?

Cheers,
Richard

 

"DSLRs for Dummies"

Seriously, do pro cameras ever have "idiot" modes?
You know, like a little face logo for portraits, a mountain for
landscapes, etc?
When you see that on a Nikon D2Xs, you'll know their days are
numbered.

 

Yes, it is built in to the P mode (Program). For the last twenty years
or more, P mode has been linked to focal length in all SLRs, whether pro
or amateur.

The camera can not tell whether you are shooting sports (unless it has a
sports mode, which tends not to happen in pro models). But it can tell
what focal length your are using, and will keep the shutter speed as
short as possible at longer settings.

David

 

I assume that program mode on the decent ones can be "programmed" to do what
you you need, mine can.

 

Hi, David.

Thanks for the reply. You're correct, of course. What I had in mind is
very similar, but a bit of a hybrid.

Put another way... Program mode but with a static exposure value,
instead of auto-metering. (Like Nikon's AE Lock behavour, but without
it being reset every time the meter turns off.) Ideally, it'd work with
shutter-priority or manual (my preferred mode).

The idea being to set the EV based on incident light (so different
vehicle colors don't skew the metering) but preserve the visual effect
by adjusting shutter speed across a range of focal lengths.

Cheers,
Richard

 

Hi, Pete.

Which camera are you shooting with, and how much can the Program-mode
behavior be customized?

Cheers,
Richard

 

Um, yeah. Maybe my follow-up to David makes it a bit clearer.

Mind you, that's a great spot for user-programmed profiles (I
believe the pro models do this). But the factory-set ones on prosumers
are a waste of space.

 

My K10D has four settings in hyper program mode.

1. Normal
2. Hi speed
3. Depth of field
4. MTF priority program is an AE mode that priorities the best aperture
setting for the attached lens.

Cheers.

Pete

 

So you mean a "motion blur priority" mode? Kind of like shutter priority,
but instead of keeping the shutter fixed, it maintains the shutter speed
relative to the FL? so if the camera is at 100mm and I set the shutter to be
1/50, it would move up to 1/150 if I zoomed to 300mm. Can't say I know of
any that do it - shutter priority and dialling the shutter speed while you
zoom would be the closest. Not all that hard to do.

 

Pentax has one similar thing and I suspect Samsung does. It's a mode
where you set both shutter speed and aperture, and the ISO is varied,
and when you reach the limit of the ISO (which you can pre-set to avoid
using too low or high for the conditions) the camera will then alter the
other parameters.

However, I do not know of any camera which alters the plus-minus EV
setting to cope with changes in the colour of a car - just manual mode.

Nikon's better cameras use an external WB sensor on the prism, which
avoids auto WB errors being caused by a coloured subject filling the
frame. They do not use this sensor for exposure moderation though.

Your idea is fundamentally a good one - an external incident light
sensor on a probe, maybe, mounted on the hot shoe, to control the camera
according to the light conditions - sun going in etc - and not using TTL
metering.

So far it doesn't exist. Minolta bought in patents on a Zone System
viewfinder display which allowed the use to target one of seven zones,
and the camera would expose to match. They never used it.

David

 

There's nothing "Dummies" or "Idiot" about the OP's request. It is a
very logical feature that I desired as soon as I got back into
photography a few years ago. In very low light, doing hand-held
shooting, Av mode is extremely problematic. I tend to use Av mode when
there is ample light for fast shutter speeds, and Tv mode when light is
very low, and having a blurred long exposure is worse than having wide-
open optics or a little under-exposure. The logical extension to the
latter is to have a Tv-pri mode where you set a ratio to focal length,
rather than a fixed focal length, very useful for zoom cameras, so you
don't get unnecessary under-exposure at the wide end of the zoom range.

An intelligent photographer can make good use of automation to their
advantage, when they choose one that automates what *they* would do
automatically, if they had remembered to do so and had the time.

This feature would be more of a true "user-control" than the P mode,
which the Pro cameras do have.

--

 

Still not quite the same thing as the OP asked for; P mode *will*
lengthen the exposure instead of under-exposing, when you reach the
limits of light at the highest ISO. A mode that is unbending in SS is
another thing.

They don't make the most sales-worthy posters, but images under-exposed
by 3 or 4 stops at ISO 1600 on my 30D are still usable to some degree,
and properly downsampled are not much worse than well-exposed ISO 1600
images for web-sized images.



--

 

I'm not sure what you're implying here, but focal length has no effect on
subject blur, at a given shutter speed. Someone swinging a golf club at
1/100 will have the same angular blur at 8mm or 1200mm.

I'd want a feature like you mention, but I'd want it for static or slow-
moving subjects in compromised light (to avoid wasteful underexposure when
zooming out).

--

 

That's rather unfortunate. Exposure could be better gauged with three
separate color meters. The brightest (RAW) color would dominate the
exposure, and this could be extended to flash metering as well. WOuld be
ideal, too, for exposure modes designed for maximum RAW exposure without
clipping.

The world of digital photography seems to be doiminated by very slow
corporate thought processes.

--

 

Bingo!

I tend to shoot in manual mode, so I envision it as a menu option rather
than a button, akin to "Track shutter speed with focal length". A bit
of a hybrid between Program and Manual modes, if you will. (An
alternative might be to allow a manual EV setting with Program mode.)

Certainly this feature would be off by default - it's not the behavior
anyone would normally expect when manually setting the shutter speed.

Alas, it sounds like this might be a pipedream. Unfortunate, knowing
that it'd be pretty easily implemented. Maybe one day camera firmware
will go open source, and we can tweak away.

Cheers,
Richard

 

Why not buy a lens with IS? Then use Shutter Priority at 1/125 or even
1/60.

 

That was my first thought, too, but here's another way of thinking about it:
Imagine two 8x10s, one a wide angle of a golfer taking a swing, the other a
close-up of the club head as it's in motion. Same shutter speed reveals the
same amount of movement, let's say, a half an inch. In the wide angle
image, that half an inch will occupy a tiny fraction of the print's surface,
so little that it's a saleable image. In the close-up, it would occupy
considerably more. So to get a saleable image with the close-up, he has to
up his shutter speed.

 

Any such mode (like other such modes) would be only the roughest guess
at what would be needed.
There is no way you could ever make it even marginally precise. How
does the camera know how fast the action is?
Maybe in the future, a system of sensor feedback (could the sensor
detect subject motion?) accelerometers in-camera could be used to
facilitate something more accurate.

 

Sure it does: speed of image on sensor=speed of subject*magnification,
and magnification depends on the focal length (amongst other things).

Or thing of taking a photo of an airplane passing at a distance of
200m with a) a 10mm lens and b) a 1000mm lens, everything else the
same.

 

THINK!!!