The rule of thumb for which I've never understood any proof of, comes from
comparing 35mm to med fmt to large fmt. The DOF of a normal lens decreases
as the format increases. So a 50mm digital zuiko should have more DOF than a
100mm OM zuiko for the same size prints. The handwaving I've seen says the
difference is relatively small, which I take to mean that a 50mm digital
Zuiko telephoto will have less DOF than a 50mm OM normal lens. I've never
seen any numbers just a claim that the format effect is small.
Probably an hour of playing with several of the DOF calculators adjusting
the circle of confusion to account for the different magnification to get
the same final print could give a better feel.I don't know how accurate the
various DOF calculators are. The links I have are;
http://www.dudak.baka.com/fovcalc.html
http://www.fineart-photography.com/dof.html
http://www.fineart-photography.com/dof.html
http://www.dof.pcraft.com/dof.html
-jeff
----- Original Message -----
From: "Daniel Tan" <daniel.tan@xxxxxxxxxx>
To: <olympus@xxxxxxxxxxxxxxx>
Sent: Wednesday, November 12, 2003 5:58 PM
Subject: Re: [OM] E-1 bokeh?
> True, but from what I gather from the way the 300D works, the "focal
> length multiplier" (1.6 for the 300D, 2 for the E-1) is not actually a
> multiplier. Instead, it just cuts down the FoV for that lens in order to
> gain a similar FoV that the equivalent focal length would produce. The
> DoF remains at the original focal length however. What I'm asking is how
> does, say a 50mm lens on the E-1 (100mm equivalent) compare to a similar
> 100mm and a 50mm on your favourite OM at the same aperture?
>
> Daniel
>
> -----Original Message-----
> From: owner-olympus@xxxxxxxxxxxxxxx
> [mailto:owner-olympus@xxxxxxxxxxxxxxx] On Behalf Of Jeff Keller
> Sent: Thursday, 13 November 2003 1:31 AM
> To: olympus@xxxxxxxxxxxxxxx
> Subject: Re: [OM] E-1 bokeh?
>
> An image at greater magnification from the same lens would generally be
> considered to have a smaller DOF. The blur gets magnified also. With
> smaller
> FOV the final image would be viewed at the same distance.
> -jeff
>
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