--On Friday, July 21, 2017 10:45 +0200 Ted Lemon <mellon@xxxxxxxxx> wrote: > FWIW, presbyopia doesn't make it difficult to read things that > are distant. What does that is myopia. I've had myopia > since I was a kid. There is just a limit to how much we can > cram onto a slide, and it's actually really difficult to know > what that limit is when you are _preparing_ the slides. Ted, in the last several years, I've gotten a rather comprehensive set of personal lessons in things that can go wrong with vision. More than presbyopia can be age-related or at least have age as significant risk factors. I hope no one else in this community finds out first-hand about any of the others, but they are out there. My knowledge is still incomplete and I hope to never complete it, at least in the same way). For those reasons and reasons that relate more closely to our policies about treating each other professionally and with respect, I suggest that, if someone says they can't see something, I think we need to take them at their word and start figuring out what to do about it rather than probing diagnoses or terminology. Narelle's note is very helpful in that regard: While, if slides are simple black type on white backgrounds, type size and choice of type styles are usually the major readability issues, there are, as she says, others (and good choices of style and contrast can mitigate size issues to a certain extent). Contrast and glare are, as Nary more or less pointed out, are room environmental factors over which presentation designers usually have little control (if one wanted a way to overconstrain site selection very quickly, take specific requirements about that to MTGVENUE although we often have control over dimmers and whether spotlights are on or off and probably don't take enough advantage of it). > I suspect there is standards work to be done here. E.g., is > it the case that the relative size of the screen when seen > from the back of small rooms is the same as from the back of > large rooms? >... There has actually been a good deal of research work, whether "standards" or not, done on this. The links in Narelle's note are a reasonably starting point (I would have suggested others, but they are no better, just different). For more general discussions about avoiding clutter and distractions that interfere with rapid and accurate understanding, see Ed Tufte's work (what works well for the somewhat visually impaired does not always correlate with clutter reduction, but they are often linked). However, a warning: Tufte has often made comments to the effect that Powerpoint should be treated as a disease. > I say this slightly tongue-in-cheek, but it's a real problem > that I really had to think about when preparing my slides. I > was not able to come up with a definite answer. I don't know > how well I did, to be honest, but I did increase the font size > above the default, which seemed pretty eye-chart-ish to me. In my experience, even thinking about the issues is a huge step forward and improves the results. If one is composing slides on a typical laptop screen and one has roughly normal vision, simply stepping away and trying to see if they those slide be read and understood from two or three meters away can be very instructive. Again, it is possible to do much better than thinking plus that test will yield, but they are big steps. john p.s. I've been thinking about a room setup in which 300-500 people could all sit AT the front. It is actually an interesting design exercise even though I don't think I've ever seen a meeting space in which rows of seats are arranged above each rather than front to back (a few opera house might come close, but AFAIK we haven't considered those for meeting venues yet. :-)