[Leica] More Nerdy stuff.... Sony A7 with Leica lenses.

[Paul Roark]

Hi Frank,

Although I almost never use filters (in part because black and white prints
are my target, using a Sony a7r--), when I did, I undertook a lot of
testing to optimize the image.  Although this testing was about 20 years
ago, I found that, among those I tested, only the German B+W and (another
German filter maker I'm not seeing these days and whose name I've
forgotten) did not cause any reduction of image resolution.  For most
photography, they're probably all fine, but for those doing large prints
where image quality across the frame can be critical, you might want to
look into this potential source of image degradation.

Paul
www.PaulRoark.com

On Mon, Jun 1, 2020 at 10:08 AM Frank Filippone via LUG <lug at leica-users.org>
wrote:

> On Ric Carter's and Aram's suggestion, I went out and tested the color
> shift issue ( shadows turned purple) issue with a B+W 486 type filter (
> my Sony A7rii Kolari modified UT or V4 ( same thing) camera.
>
> The results were quite positive...
>
> A shot done WITHOUT the filter produced purple shadows, and probably
> purple all over.
>
> The shot WITH the filter, produced considerably more neutral grey colors
> in the shadow areas.  Which states that the modified cover plate, the
> thin plate of glass in front of the sensor, is weaker to blocking UV/IR
> light than the Leica OEM glass plate, necessitating the use of a
> blocking filter to correct with the Kolari mods. Would the Leica brand
> filter work as well?  I do not know.....
>
> The problem with this is that I just ( last week) sold all my Leica
> UV/IR filters.............
>
> So much for never selling any Leica equipment.....
>
> Anyone want to sell Leica UV/IR filters?
>
> I may have to resort to putting a gray card in the photos as a target
> for white balance correction.... when it is critical.
>
> Anyway, good call Aram and Ric
>
> Frank Filippone
>
>
>
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