Re: [Leica] Performers and flare

[Edward Meyers <aghalide@panix.com>]

If only low-light photographers could use a 100 ISO speed film
and make meaningful images with slow speeds and a tripod...
It is not the case, however. So we do what we can with high-speed
films. Filling in deep shadows in high-contrast low-light
situations, without a flash (hopefully), if helped by flare,
then the photograph might look better. If only this were a
perfect world... Ed

On Tue, 8 Aug 2000, Erwin Puts wrote:

> It was noted: "Once you get past Erwin's bench tests, is there really a
> "bad" version of
> the Summicron 35?...I've owned various versions over the years - I assume,
> as I've purchased them all used at widely different period of my life - and
> they've all be terrific performers."
> 
> If this really is what the poster assumes, I can only add: if your
> definition of "terrific performers" is modest enough, he is absolutely
> right. Most Leica photographers I know however see very discernable
> differences. The performance you can extract from a lens is tightly coupled
> to technical expertise and the level of your demands and your type of
> picture taking. Without this background info any statement about good
> performance is void.
> The flare issue. Flare is defined as unwanted stray light, that will be
> uniformly distributed over the whole image area. If we have a scene from
> black to white, we will have a range of figures that indicate relative
> contrast, we have a rnage of 100 to 0.25 lux, indicating light and dark
> areas, which is a contrast of 400:1. Add a uniform flare level of 0.25 lux
> and we now have 100.25 and 0.5, giving a contrast of 200:1. The effect on
> the dark areas is big and on the lighter areas to be neglected. This example
> shows two things: flare does simply give greater negative density in the
> thin parts of the negative (the black areas), and will give a dark grey
> instead of a black, suggesting detail, which is not there.
> The old story that you can use a low contrast and/or flare prone lens to
> compensate for high contrast in the scene is not correct. The highlights are
> not affected and the dark areas just become muddy.
> The best proposal: buy a high contrast lens, use a 100ISO BW film that gives
> good toe density and expose and develop to get the maximum contrast your
> print paper can handle.
> 
> 
> Erwin
> 
>