No.

No.

j

You see through the lens by a mirror that reflects the image to the
eyepiece. It blocks the sensor so nothing is seen at the sensor until
the picture is taken a which time it moves out of the way.

$I'm newbie in SLR so I will have maybe some funny questions sometimes.:)
$I.e. I was very surprised when I learned that LCD can't be used as a
$viewfinder. (are there SLRs where it can be done?)

  Yes, there are a couple.  Olympus makes a model which can do this,
and the Canon EOS 20Da can also do this (although I'm not sure if this
capability can be used in all circumstances; the 20Da is specifically
intended to be used for astrophotography, and this capability is
designed to be used when trying to focus through a telescope or similar
device on stars in a dark night sky).  But in general, SLRs can't
do this, because the imaging sensor is behind a shutter, which is
closed until you take the picture, and the shutter is in turn behind
the mirror which directs light into the viewfinder.

$Can you apply date stamp on the picture?

  Sure; print the picture out, get one of those date stamps and an
ink pad, and have fun!

  No, the camera can't do this.  If you want an ugly date stamp
on your pictures, use a photo editing program.  I haven't looked
to see if any can be set to do this automatically (it's certainly
possible, since the camera records the date and time when the picture
was taken in the image file).

$Is it possible to see histogram before picture is done? My previous camera
$Canon S3 IS (which I replaced for rebel)I think it has that option.

  No, for the same reason why you can't use the LCD:  until the
picture is taken, the mirror and shutter are in the way, and no
light reaches the sensor.  (And for your next "My old S3 IS could
do xyz but my new DSLR can't" question, this also explains why
DSLRs don't have movie modes.)

------------------------------------------------------------------
    Say hi to my cat -- http://www.stevedunn.ca/photos/toby/

According to jazu <nofreakingspam@nospam.com>:

    You have two answers to this which are correct, so I won't cover
this again.

    However, I will mention that the normal mode for shooting with a
DSLR -- with the camera held up to your eye, and thus steadied by your
face as well as your hands -- gives you less shake in an image than
holding a P&S a distance from your face so you can see the display for
composition.

    Enjoy it.

    There is a date stamp in each image -- in the "exif data", along
with other information -- shutter speed, aperture, (perhaps) focus
distance, if the lens tells the camera about that, whether flash was in
use, lots of information about corrections and modes which may have been
selected in the camera, and (optionally) some text of your choice.  (At
least that is present in the Nikon D70, and presumably the other DSLRS
by Nikon.)

    When you process the image using some computer program (with
Photoshop being the most common choice on Windows machines), this
information should be visible.  But it may be lost when you save an
edited image.

    Some programs may offer the option to take the date (or some
other information from the EXIF data) and include it as an overprint in
your image.  I don't use Windows, so I don't use Photoshop -- so others
will have to handle that for you.

    There are programs which can scan through a directory of images
and extract the date from the exif data, and use that to create a
filename which includes the date -- or can set the system's idea of the
date last modified for the file to match the exif data.

    No -- not on a DSLR --because it has to be based on what the
sensor sees, and as others have already explained, the sensor does not
see the object to form the image until the moment of exposure.

    Because it has the sensor exposed during composition.  This is
the same reason that it can use the display for composition.  (And --
this also is why it is so long a time from pressing the shutter release
until the actual image is taken.  The shutter must close, the old data
in the sensor must be flushed out, and only then can it re-open the
shutter to take the photo.  Then -- that has to be read out to the
display to show you what you got.

    Compare that to the speed of your new camera.  (This is based on
the Nikon D70, but I would expect the Canon to be similar.)  You can
switch the camera on as you raise it to your eye, and as soon as you
have it to your eye, the camera is ready to take an image -- unless the
focus is way off, and even the autofocus is much quicker than in the P&S
cameras.  Some lenses are quicker with autofocus than others, of course.

    Enjoy,
        DoN.

With Irfanview (http://www.irfanview.com/), it is easy to put a date or time
or both stamp in one picture. You select where the stamp has to go by
marking an area with the mouse. With Ctrl-T you can add text a $T will give
you date and time, see below for the variations with different formats.
There are probably programs (not all free) which can do this as wel or even
better. Irfanview is free and does the job but as far as I know only on one
picture at the time. (In general you only want the date stamped on a limited
amount of pictures, because it is available in the exif of the picture).

Ben

From Irfanview:
Appendix A

By default, all date/time placeholders deliver full text including date and
time. If you want to get only specific values, you can use additional
placeholder options (ANSI C compatible):

%Y - year, 4 numbers
%y - year, 2 numbers (00-99)
%m - month
%d - day
%H - hour
%M - minute
%S - second

Examples for file, EXIF or system date: Year: 2005, month: 11, day: 29

Placeholder    Result text

$T(%d.%m.%Y)   29.11.2005
$T(%Y%m%d)   20051129
$T(%d%m%y)    291105
$E36868(%Y_%m_%d)  2005_11_29
$T(%d_%m_%Y)   29_11_2005
$T(day:%d, month:%m, year: %Y) day: 29, month: 11, year: 2005

Jazu-

There are less expensive versions of DSLRs with a non-interchangeable
lens, that use the main sensor for the viewfinder, just like with a
point-and-shoot.  They have an option to show the view either on the rear
LCD, or a tiny LCD inside.  I don't think you would be satisfied with this
class of camera after using the XT!

Check the XT manual to see if it has "Digital Print Order Form" (DPOF)
capability.  Using that in conjunction with a printer or print service
that supports it, you can have the date printed on the picture.  This
method does not apply the date to the digital image, just the print.

Fred