SLR focussing
sridhar
the Canon 28-105 mm lens. I shot one roll and was pretty pleased with
the picture
sharpness.
With my second roll, I was trying to shoot a landscape at
6 in the evening. I had the camera set on a tripod with a shutter
release, in manual mode. I used the autofocus to frame the landscape
lit with the last lights of the setting sun.
After the picture was in
focus, when I pressed the shutter release completely, it would shift
to an out of focus picture. Each time I pressed the shutter release,
it was shifting between out-of-focus picture and in-focus picture, but
was never capturing the picture. I am not sure if this is a defect on
the part of the lens or is it because it could not detect the object
to
focus on ? I later came home and tried to focus on differnet objects
and it seemed to focus.
I want to know if there is some defect in the lens or is it just the
lack of light ? ( In my first roll, I shot the same landscape, perhaps
with a li'l better sunlight, but it came out very well)
Any help on this matter would be appreciated.
thanks in advance,
Sridhar
JR
There is nothing wrong with your lens or camera. Number 1, in low light
situations, it is hard for cameras to focus. Number 2, what was your
focus point? If your focus point was not clearly definable in the center
of the viewfinder, or if you have more than one focus point selectable,
under the selected focus point, then it will have a hard time focusing.
Number 3, speed of your lens. The faster and more light efficient your
lens is, the better it will focus under lower light conditions. If you
need to focus your lens under low light situations, then switch to manual
focus.
JR
Ahriman
"sridhar" <sridh...@hotmail.com> wrote in message
news:bffd146b.01112...@posting.google.com...
Switch autofocus off - it is a killer for landscape pictures. What is
happening is that you are setting the AF by aiming it at the landscape, then
you are taking your finger off the shutter, re-composing, and the AF is
simply trying to lock on to whatever is in the centre of the AF point when
you touch the shutter button again - and if this is blank sky, there will be
no sharp edges for it to lock on to and it will hunt all the way through its
focus range, thus throwing your whole image out of focus. Switch AF off and
focus it yourself. I always switch it off on my Nikon when composing a
landscape shot, it just gets in the way, like autoexposure mechanisms like
aperture and shutter priority. It is one of those situations when automation
actually impedes the taking of a photograph rather than assisting it! It is
also worth bracketing your focussing to see whether it works best with the
focus at infinity or focussed on the foreground (both, naturally, with a
smallish aperture (f8 or f11 is about optimum).
Ahriman
James Morgan
viewfinder it may have been messing things up. OK to use autofocus to get
focus, but then turn it off and remember to cover the view finder.
Erik Dahlbeck
>Switch autofocus off - it is a killer for landscape pictures. What is
>happening is that you are setting the AF by aiming it at the landscape, then
>you are taking your finger off the shutter, re-composing, and the AF is
>simply trying to lock on to whatever is in the centre of the AF point when
>you touch the shutter button again - and if this is blank sky, there will be
>no sharp edges for it to lock on to and it will hunt all the way through its
>focus range, thus throwing your whole image out of focus. Switch AF off and
>focus it yourself.
>
Or, alternatively, you may focus at the desired point using AF, *now*
turn the AF off and recompose.
--
Erik Dahlbeck
Echo-Romeo-India-Kilo Delta-Alpha-Hotel-Lima-Bravo-Echo-Charlie-Kilo
Erik Dahlbeck
>Did you have eye controlled autofocus selected?
>
Hmm... Isn't the Elan 7E the EOS 33 which is the non eye control focus version of the EOS 30? Or is it the other way around...? Could the "E" be for "Eye"?
Skip
Skip
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Skip and Heather Middleton
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Bill Tuthill
> Hi, I am a beginner and I recently bought a Canon Elan 7E camera with
> the Canon 28-105 mm lens. I shot one roll and was pretty pleased with
> the picture sharpness.
>
> completely, it would shift to an out of focus picture.
This is called "hunting".
The Elan 7e / EOS 33 is specified to autofocus at 1 EV of light.
Nikon and Minolta specified better low-light autofocusing in their
equivalent cameras, the N80 / F80 and the Maxxum / Dynax 5. Both
these models autofocus as -1 EV.
sridhar
Thank you for the various responses to my query. Answering some of
them, my 7E is the one *with* the eye control, but I did *not* use it
on that occasion. The picture I was trying to frame was with the
mountains in the lower 1/3rd and the
vast skyline in the rest of the picture. The skyline was lit with
streaks of red and orange colors, but quite light in intensity.I shall
try the shot with manual focussing the next time.
Also, I was wonering, if any of you use the depth-of-field preview
button on the SLRs frequently. Is it useful for situations like
landscapes etc. On a recent hiking trip, I set the
aperture to f/22 for a sweeping landscape picture and depressing the
depth-of-field preview button did not seem to assist me much (Apart
from making the image on the viewfinder darker)
Any help would be appreciated.
Thanks in advance,
Sridhar
"Ahriman" <ahr...@nospam.com> wrote in message news:<9thad6$o0q$1...@newsreaderg1.core.theplanet.net>...
> "sridhar" <sridh...@hotmail.com> wrote in message
>
Ahriman
> Also, I was wonering, if any of you use the depth-of-field preview
> button on the SLRs frequently. Is it useful for situations like
> landscapes etc. On a recent hiking trip, I set the
> aperture to f/22 for a sweeping landscape picture and depressing the
> depth-of-field preview button did not seem to assist me much (Apart
> from making the image on the viewfinder darker)
>
> Any help would be appreciated.
Using DoF preview is something that needs a little practice. It shows you
just how much depth of field you have, but as you say, seeing through the
darkened viewfinder is tricky. The trick is to let your eyes get used to the
lower light for a minute. I use it only occasionally, I tend to be pretty OK
at guesstimating DoF.
Ahriman
obakesan
In article <3BFD4C11...@delta.telenordia.se>, some kind human wrote:
>Or, alternatively, you may focus at the desired point using AF, *now*
>turn the AF off and recompose.
a true pain in the butt with a tripod though
See Ya
--
(when bandwidth gets better ;-)
Chris Eastwood
Photographer, Programmer, Motorcyclist and dingbat
please remove u n d i e s for reply
obakesan
In article <bffd146b.01112...@posting.google.com>, some kind
human wrote:
>Also, I was wonering, if any of you use the depth-of-field preview
>button on the SLRs frequently. Is it useful for situations like
>landscapes etc. On a recent hiking trip, I set the
I use it often ... however if everything is further away than say 5 meters,
then you are not going to see much really, think of the DOF distances and
you'll see that everything is more or less in focus anyway especially with
a wide angle lens.
now, try it with a lens of say 50mm or greater in focal length (zoom fine
for this too) and focus on something at about 2 meters away (say a leaf or
flower) and have clear view to the distant background in the viewfinder.
press your preview, and notice how the blurred background now becomes that
much clearer (as well as darker)
you can use this to 'preview' how your background will look on the print,
is it as fuzzy as you want? is it too clear??
don't use it for critical focus, its not really that accurate, but it is
nice to have a visual confirmation. Decent lenses (especially on MF lenses)
have nice DOF markers on them for making calculation of the range of focus
you can expect. I use this conservatively and am usually happy
>aperture to f/22 for a sweeping landscape picture and depressing the
>depth-of-field preview button did not seem to assist me much (Apart
>from making the image on the viewfinder darker)
>
>Any help would be appreciated.
>
>Thanks in advance,
>Sridhar
>
>
>
>
>"Ahriman" <ahr...@nospam.com> wrote in message
> news:<9thad6$o0q$1...@newsreaderg1.core.theplanet.net>...
>> "sridhar" <sridh...@hotmail.com> wrote in message
>>
>> Switch autofocus off - it is a killer for landscape pictures. What is
>> happening is that you are setting the AF by aiming it at the landscape, then
>> you are taking your finger off the shutter, re-composing, and the AF is
>> simply trying to lock on to whatever is in the centre of the AF point when
>> you touch the shutter button again - and if this is blank sky, there will be
>> no sharp edges for it to lock on to and it will hunt all the way through its
>> focus range, thus throwing your whole image out of focus. Switch AF off and
>> focus it yourself. I always switch it off on my Nikon when composing a
>> landscape shot, it just gets in the way, like autoexposure mechanisms like
>> aperture and shutter priority. It is one of those situations when automation
>> actually impedes the taking of a photograph rather than assisting it! It is
>> also worth bracketing your focussing to see whether it works best with the
>> focus at infinity or focussed on the foreground (both, naturally, with a
>> smallish aperture (f8 or f11 is about optimum).
>>
>> Ahriman