Not useful, have it on two cameras and rarely use it, the newest camera has
digital DOF preview as well and that is much more useful.

It is useful for macro, but it's a rough guide only, as at small
apertures the screen will be dark, and the type of screens in AF cameras
don't give a true indication of DOF - like could be seen on old ground
glass screens.  Chimping the LCD works if you don't have a DOF button. I
wouldn't consider it a deal maker/breaker, but handy to have sometimes.

   There is no easy answer to that question.  I find it useful, and I
certainly would want it on my next camera as well, but I do not use it
often.  For most photos it is not an issue, however for the few where it is
an issue (because I want a small carefully defined DOF or because I need a
large DOF) it is very important.

   Your style, subjects tolerances and preferences will make the
difference.

On Feb 21, 3:04 am, screenacco...@gmail.com wrote:

Various ways to answer:

(a) Use it once and you'll realize it is a worthless option.

(b) Anyone who says they use it are probably lying.  (Yes, it's that
worthless).

(c) If you have to use it, you probably don't have enough depth of
field.

(d) With a digital camera, take a picture and evaluate.  Let the film
freaks howl in agony at the increase in general prosperity.

When DOF is an issue in the "unreproducible shot" scenario, they
remember simple approximations and do some arithmetic in their head.
But few do, instead working to improve the camera-subject geometry so
precise depth of field becomes unimportant.

I had DOF-P on my D70 and it was pretty worthless because of the dim
viewfinder. On the D200 I find it very useful because the viewfinder is
that much better (same on D80). It's useful for macros and anywhere that
you're working with blurring out the background and gives a pretty close
to accurate feel for the depth of sharpness and size of out of focus
highlight circles, or when the background goes from a bunch of
distracting circles to a nice soft blur. For closeups I use it to
establish what is enough DOF for the subject then release to pick the
final focus point. I don't think it's much help for trying to get really
deep DOF as in landscapes because you can't see enough detail and at
f/8, 11, etc. the viewfinder becomes too dark. On the D200 with old AI
lenses, you can hold down DOF-P while turning the aperture ring and see
it click click click through the range, where on modern lenses, it's a
more awkward process of spinning the command dial and pressing the DOF-P
button for each step.

Ask yourself the following questions:

1) How important is control of depth of field to your photography?

If it is important, or very important, go to Question 2.  If it is not
important, you have answered your own question.

2) If control of depth of field is important to your photography, how
can you manage without depth of field preview?

If you use lenses that have accurate depth of field markings that you
feel you can trust, you may be able to manage without depth of field
preview.  After all, those of us who use rangefinder cameras can only
predict depth of field from those markings on our lenses.

It does seem silly to choose an SLR, one of whose strongest advantages
is being able to view the image produced by the lens, and then decline
to take advantage of the SLR camera's ability to preview depth of
field.  The fact that you have posted your question on here at least
indicates that you are aware of that.

However, even if you choose a Nikon DSLR other than the D40, you may
be faced with having to install a third party accessory focusing
screen in order to be able to view a representative depth of field.
That is because most DSLRs have focusing screens that are designed to
give the brightest possible image in the viewfinder, and that usually
means that the ability to view depth of field is limited - unless of
course you change that screen.

No. Over the last 40 years I've owned SLRs with and without the so-called
depth-of-field preview feature, and seldom used it. It is of some use in
situations such as macro and portraiture work where you want to get a vague
idea of how much the depth of field is and how out of focus the rest of the
picture is, and that's about all. A little experience in such photography
will probably do you more good than the DoF button on the camera.

But some people evidently love it. A friend of mine insisted he used it "all
the time." I don't know if he really did. People just seem to like to push
the little button and imagine the viewfinder is really showing them exactly
what the depth of field is. That it simply cannot do; the viewfinder cannot
possibly convey the DoF as it will be in a final print or other enlarged
image.

The D40 is a very fine choice as a first DSLR.

Neil

Sometimes useful. The depth of field preview on other Nikons also triggers
the i-TTL lighting so you can preview the effects of your lighting. But the
D-40 doesn't even have commander mode, so that takes away a major use of the
depth of field preview.

Another use of it is when taking multiple shots of a subject at different
apertures so that when they are all merged together you have a larger depth
of field than in any one of the shots. DOF preview helps make sure you don't
get any blind spots.

The big problem with DOF preview is that it usually makes the viewfinder so
dark that you do not have a clear view of the effect.

I don't think I could bring myself to buy a camera that didn't have a
stop-down preview. Bright viewfinders and stop-down preview and mirror
lock-up (or at least 2-second delay) are dealbreakers for me.

In fact, that's a big part of why I don't have a Nikon DSLR. :-)

Note also that some lens mounts will allow you to unlock the lens and
turn it without taking it off, causing the aperture to stop down. I
can't recall if Nikons can do this, but others can. Call it a 'poor
man's DoF preview.' Remember to re-lock the lens when you're done. :-)

It's a rough guide.  Use it on less than 10% of my shots (prob'y less
than 5%), but I'm happy to have it when it's needed to help judge the
DOF.  Some of my lenses have somewhat useless lens markings for DOF.