That advice, repeated several times troughout the book, would almost certainly result in slides that are badly overexposed and
probably unusable!
The reason for this is simple, it was based on the film widely available at the time which was typically ASA 10 .
No, I'm not kidding, that's ASA TEN, not one hundred. By the late 50s ASA 32 was common and by the late 60s and
early 70s ASA 64 was common place, so that advice became dated soon after the book was published.
Most of today's slide shooting is done with ASA 64 or ASA 100. It should also be noted that contemporary slide film
has much more lattitude than
50s era films and slide film is far more tolerant of underexposure than overexposure. In fact, slight undexposure improves saturation
and gives a very pleasing effect with many subjects. With these facts in mind, I will offer the following advice for present day
users of Realist cameras: