[Leica] New tutorial on my photo lessons website

[Eddy Willems]

indeed if you speak about the new Kodak gray card R27 which I didn't 
know was on the market and which never have seen in Europe an is 15% 
reflective



the one we can buy in Europe is the old one 18 %
here you see the difference



Op 3/02/17 om 19:53 schreef Christopher Crawford:
> The Kodak card is supposed to be neutral and usable for white balance. The
> info sheet that comes with it states that, and shows a spectral response
> graph showing that as well. I¹ve done numerous tests with it and it gives
> consistent results in all types of light, though the results are (as I
> state in my tutorial) very slightly warmer than the results obtained with
> the other cards.
>
> I think the Xrite Colorchecker Passport¹s white balance squares are the
> very best. The differences between the Colorchecker Passport, Whibal, and
> Kodak Cards are subtle though. Each of the cards I tried gives slightly
> different results.
>
> On the Colorchecker Passport, Xrite says that you should not use ANY of
> the white or gray squares on the passport¹s page that had the old Macbeth
> Colorchecker chart, as these are not truly neutral. Instead, they say to
> use one of the two white balance pages. One is a large light gray page.
> The other is on the page opposite the traditional Colorchecker. That page
> has two lines of white balance squares. One is labeled Portrait, the other
> Landscape. Each line includes a true neutral square and the several
> slightly non-neutral squares that allow you to choose a slightly warmer
> white balance (on the portrait line) or a slightly warmer or cooler white
> balance (on the landscape line).
>