Im zauber Des Lichts 1940

by Walther Herring....
I found this book at the University library. My knowledge of the German language is almost nonexistent even though my paternal grandfather came from Munich. I have made out that the book appears to be about Rollei cameras and 6X6 in particular. I can understand what aperture and shutter settings are in the photos featured. But I had to use my English/German dictionary to find the color of filters used along with a few other words and phrases. Would someone here have a little more information on this title?
As someone who uses old German gear (1936 Voightlander,1947 Zeiss + a Leica M3), I am always on the lookout for information pertaining to their use. I did a search on the 'net and I see that there may be some English translations. Maybe I need to break down and add a Rolleiflex to my collection!
Thanks to anyone for your help.

Dr. Walther Heering (not Herring, though it’s most probably the same meaning…) is known to me in first instance as publisher.

He received his PhD in philosophy and founded, in 1932, a publishing house for photo-books which became one of the most important of its kind in Germany. Next to pictorial books, seemingly aimed at a quite broad readership, technical photographical guides were published. I guess there is be nobody with a few german language photobooks in house who has not got at least one title from this publishing house. The publishing house was in existence under the name Heering Verlag as book publishing house until the 80’s.

His greatest success was publishing with author Hans Windisch the “Neue Foto Schule”, a book which eventually yielded 580,000 prints in many languages.

Remarkable also the pictorial book on colour photography “Im Zauber der Farbe“ from 1943, a time when no colour films were sold anymore.

His first titles after the end of WWII were anti-fascistic titles in 1946, with Windisch again, but also in the same year the founding of the first post-war photo magazine.

For his own photography you might look at “Meine Foto Praxis”.

You won’t find much about himself.