--- Terry Danks <[EMAIL PROTECTED]> wrote:
> I can't say as I can see how having a smaller sensor
> can possibly be an advantage. From that point of
> view
> I agree with Bob's comments.
>
>> Still, I do not quite understand how the D30
>> actually manages to turn the image from an "x mm"
>> lens into
>> the equivalent of an image formed by a longer lens.
>> Is the viewfinder of the D30 such that it appears
to
>> be
>> a telephoto shot? How is the image formed without
>> turning the lens into a slower f stop as well?
>> How does this work? What is thrown away? I am
>> perplexed.
Consider the CMOS sensor of the D30 simply as a
regular film with a different film size. So the only
thing that changes is the film format. Everything else
stays the same including the physics of the lens.
Therefore, the focal length and the aperture are still
the same. If you keep the same distance to your
subject the perspective will also remain the same.
So where does the 1.6 come from? Well, imagine the
CMOS sensor has the size of an APS frame. Now instead
of a 35mm film you insert an APS film with each frame
centered in the middle of the 35mm frame. Obviously,
the APS film will capture only the middle part of the
35mm film. This makes it look like you used a lens
with a longer focal length. In reality you just
cropped the 35mm film. The light from the lens still
covers a >43mm circle.
Robert
__________________________________________________
Do You Yahoo!?
Yahoo! Photos - Share your holiday photos online!
http://photos.yahoo.com/
*
****
*******
***********************************************************
* For list instructions, including unsubscribe, see:
* http://www.a1.nl/phomepag/markerink/eos_list.htm
***********************************************************
