Re: Mystery El Nikkor Enlarging Lens

"Jorge Omar" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> Let me take a guess over here.
> A taking lens is placed btween a tridimentional space and a flat
> negative, with part of the image in focus, part out of focus, and corners
> are many times in the (even slightly) out of focus area, so it really
> doesn't matters very much.
> On the other hand, the lesser elements a lens has, the less flare (for a
> given coating) there will be, so the tessars are considered as having a
> high contrast (at least in the center).
>
> An enlarging lens is placed between two flat surfaces, and one looks at
> grain to see if there is perfect focus. So corners are more critical.
>
> Jorge
>
Absolutely. Flatness of field is critical in enlarging. Using a symmetrical
lens design helps.