One minor thing when you read the spreadsheet is that the scale in the bottom does not maintain consistency. In Phil book the majority of the spreadsheet use 1/3 as the unit and also maintain the log. scale. Only SBR and development time is linear. Not in this spreadsheet:
figure 5 - print 1/3 stop per cell (scale is .1)
figure 8 - cumulative or all the film curve - 1/4 stop per cell (scale is .075)
figure 9 - first film - 1/2 stop per cell (scale is .15)
figure 10 - sixth film - 1/2 stop per cell (scale is .15)
figure 11 - EFS - 1/4 stop per cell (scale is .075)
The key change is the result graph, as it shift from log scale to non-log / linear scale:
figure 12 - SBR vs EFS - EFS is non-log scale i.e. 1 cell is 1 stop first, then 2 cell is 1 stop, then 4 cell is 1 stop
(It is not that strange and in fact "normal" way of presenting number i.e. using a linear scale as you just 50, 100, 150, 200, 250, 300, 350, 400, ....in other words 50 to 100 is 1 stop and 1 cell; 100 to 200 is 1 stop but 2 cells; 200 to 400 is still 1 stop but 4 cells. Just each stop takes different number of cells here and as the photographic world works in log scale, it is not natural.)
figure 13 - so is the EFS vs development time (which, btw, Phil did the same using linear scale on both x- and y- axis)
As I overlook this it take me a few days (to go through Phil's book in my Kindle under iPAD, which like all kindle very hard to digest if you are not reading it in a straight line fashion) to correct my misunderstanding and finally alert the scale changed. In between the confusion, even have to dig into 1st Ed of the Way Beyond to double check the scale used. Minor issues that waste a few days on me.
In brief and once again, one can appreciate that the whole thing is quite a bit of effort, especially if look at Phil's book having so many version of arriving at EFS. The way the writer to put a moving triangle as a graphic device is great.
Unfortunately the spreadsheet is protected and hence use it or nothing you can do about it. I think e.g. the original question of 31 steps (by Sandy King) is still valid today. End of line now and hence sad, especially 2nd edition of Way Beyond is still has no computer aid tool and BTZS is the only system in play. As said, it becomes more and more difficult to use that system without upgrade.
But anyway a good exercise and once again thanks for sharing.
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Originally Posted by dng88
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