[Leica] new Puts article

[bdcolen at comcast.net (B. D. Colen)]

Steve, I make no bones of the fact that I am weak on the technical stuff -
start talking circles of confusion and I circle the wagons - but I do
believe I am correct on this. Further, you've raised I point I admit I've
yet to understand - and that's the question of the "crop" and the need to
"enlarge" it. It doesn't seem that you're "enlarging" it - WYSIWYG, no?
Mount a 50 on a camera with a 1.5 crop factor, and the image you get appears
the same as though shot with a 75 on a full frame. Or, put an 85 on a 2 1/4
and don't you get a "reduction" equivalent to a 50 on a 35?


On 6/25/05 6:51 PM, "Steve Unsworth" <mail@steveunsworth.co.uk> wrote:

> Is this true? Since you have to enlarge a cropped version more won't the
> circle of confusion come into play - i.e. the depth of field will reside
> some where between the 35mm and 1.5 version.
> 
> Steve
> 
> 
> -----Original Message-----
> From: lug-bounces+mail=steveunsworth.co.uk@leica-users.org
> [mailto:lug-bounces+mail=steveunsworth.co.uk@leica-users.org] On Behalf
> Of B. D. Colen
> Sent: 25 June 2005 19:51
> To: Leica Users Group
> Subject: Re: [Leica] new Puts article
> 
> 
> Nope. The depth of field is indeed independent of the crop - it's the
> same as the "real" focal length of the lens. But that means that when
> you shoot with a 35 mm lens with a 1.5 crop factor, you are getting an
> image that looks like you shot it with a 52 mm lens, but with the depth
> of field of a 35. So your 50 1.4 becomes a 75 1.4, but with the depth of
> field of a 50 1.4
> - which actually is probably an advantage in that case. :-)