Origin of different scales, IX and X as pure white?

<p>Hi,</p>

<p>I have to ask this dumb question. It has haunted me for years and haven't found answer even during recent 10 years of google.</p>

<p>I have originally learned ZS from adamses books, where IX is first barely distinguishable gray from pure paper white. However, there's a lot of literature referring IX as pure white and VIII as first distinguishable tone from pure white.<br>

Where is the origin of this difference? And what is the reason behind it?<br>

Is it from the Beyond The Zone System book, where a bit shorter SBR is used than Adams used?</p>

<p>Regards,<br>

Jukka</p>

 

<p>I once quizzed a photography teacher on this, and he said it was due to differences in lattitude with various film and developer combinations.</p>

<p>Adams defines Zone X as the base white of the paper resulting from specular highlights. Zone IX is just a whisker below X and defined by Adams as 'white without texture'. I place non-specular whites, e.g. pure white painted surfaces obliquely lit, for example, on Zone IX. Adams does note that it may not be possible with small format negs printed on a condenser enlarger to distinguish between IX and X.</p>

<p>Okay, the origins are there. Also found some information when browsing throuh my pile of books. In the book BTZS Davis writes that as industry standard for normal contast is 7 stops, same is used in this book and thus zones 0, I, {II, III, IV, V, VI, VII, VIII}, IX. With these the SBR range is "standard" 7 stops.</p>

<p>This is a pity. One has long used traditional numbering where IX is not pure paper white, but almost. Then some other photographers uses different scale, but still referring to ZS, some to BTZS.<br>

When you usually can learn a lot of other photographers photographs if they tell to you about the exposure process. I put lightest part of her face on VIII and ... Then if another uses different scale, you are soon both lost. If photographer is follower of traditional numbering, then it is okay to put highlights to VIII, but if you as listener have most of the knowledge from BTZS etc. variants, you began to wonder that why did photographer put highlight so up?</p>

<p>As a side note, like I said, I have been always used full 0-X scale, but I have always been interested of sensitometric approach - but to get all of it, should use 0-IX scale, otherwise any other's results are not comparable with your's.<br>

Or perhaps it would work if you standardise your normal as BTZS's N-1...</p>

<p>Something to this old thread. Still a bit mystery.<br>

I just re-read my old Adam's Negative (from 50's) and in that book the zone values goes from 0 to XI.<br>

So when did zone X come to the terminology?</p>

<p>Zones are not equal with other's zones :)</p>

<p>Over the years Adams modified his concept of the Zone System to include 11 zones (I don't recall when he did this). Other photographers (Picker, White, others) continued to use the 10 zone system. My own photo reference books are packed away in a closet but you should be able to find this info online.</p>