The problem here seems choice of words. You seem fed up with "crop
factor" but willing to apply "field of view equivalence" to describe
what happens when you change the size of the film or sensor used to
capture the image.
I enjoy very much using the 24mm, had used the 50mm only because it's
bright, and 90% of my portrait was made between 100 and 135mm - in the
35mm format. The moment I buy a micro4/3 or APS sized sensor I'll have
these lens I own change their role. And will have to search a new option
to my wide angle needs. Call it aardvark or pink panther, there is a
numeric relation that will help me translate the lens to their new use.
The same as my 120 and 4x5 experiences. I hate some words myself, and
don't wish to seem champion for the "crop factor" idea. But I'm willing
to touch the matter of "diferent viewing angles" for the same lens used
by different format cameras very often - there is always some newcomer
around that may benefit of the matter.
The point is, the very same lens collection we are willing to keep in
use is going to assume a new dimension the moment we buy a new camera
with a different size of sensor. So there is no free lunch - there is
always a price to pay.
Luiz Felipe
Godfrey DiGiorgi escreveu:
On Jan 15, 2009, at 9:02 AM, Jaume Lahuerta wrote:
But, then, in m4/3, the same 24mm produces an AOV equivalent to a
48mm on film. Well, if you like this field of view, great, but, in
any case, if you used to use the lens for landscapes, now you HAVE TO
add a wider lens to the system and use the 24mm for other purposes.
And suddenly, for some people, the 24mm won't have the same appeal
that it used to, so, again for some people, the idea of buying a new
system in order to be able to use the lense probably wasn't as good
as it seemed.
Using a 20mm focal length on FourThirds format produces the same
result as using a 35mm lens on a Leica M4 and printing an 11x14 inch
print with the full vertical field of view, cropping on the long axis.
Remember that the FourThirds format proportion is different from
35mm's 2:3 proportion, which is not reflected in the "crop factor",
based on diagonal measure. Vertical field of view equivalence is
1.83x, horizontal is 2.1x.
So yes, you need a different focal length lens if you want a wider
field of view. But that's SOP for anyone moving between formats. Big
deal.
Personally: I use adapted older lenses primarily to obtain fast,
compact, well corrected portrait and tele field of view. For wide
field of view, I use FourThirds lenses as they are better designed for
the format.
EG: The aforementioned M50/1.4 lens, fitted on the Olympus 1.4x
teleconverter, produces a superb 70mm f/2 lens that is small, light,
with a field of view equivalent to something in the neighborhood of a
135mm lens on 35mm film. A Color Heliar 75/2.5 will be about the same
and even smaller, lighter. This FoV was always one of my best
favorites when I want tele. A 135mm f/2 lens for a 35mm SLR camera is
a rarity, and large/heavy/expensive.
Godfrey
--
PDML Pentax-Discuss Mail List
[email protected]
http://pdml.net/mailman/listinfo/pdml_pdml.net
to UNSUBSCRIBE from the PDML, please visit the link directly above and
follow the directions.
--
Luiz Felipe
luiz.felipe at techmit.com.br
http://techmit.com.br/luizfelipe/
--
PDML Pentax-Discuss Mail List
[email protected]
http://pdml.net/mailman/listinfo/pdml_pdml.net
to UNSUBSCRIBE from the PDML, please visit the link directly above and follow
the directions.
