Talk:Zone System

message: ... according to my understanding of how the articles should be named, then redirected the former to the latter. --NathanHawking 23:38, 2004 Sep 28 (UTC)
:Zone System is a proper name and should therefore be capitalized.  Maikel 00:20, 28 June 2007 (UTC)
thread_title:  Moved "Zone System" content to this "Zone system" page... 

message: A distinction needs to be made between slide and digital. You simply cannot underexpose for slide film, in the same degree as digital...with this in mind I have removed the reference to slide being similar to digital. I feel that it is not.
Slide needs correct exposure, significant underexposure will ruin a photo. Limits of dynamic range over the lattitude of slide are countered best with a ND graduated filter...
I also feel that in certain parts, ie Dynamic range, should also be linked and explained as similar to latitude. Possible that the style is somewhat overbearing and not simple enough to get the message through
—Preceding unsigned comment added by Barryfitzgerald (talk • contribs) 
:I'm not sure I agree with you about underexposing slide film. Just how much underexposure are you referring to? I must admit I'm still quite new to slide film. I slightly overexposed my first roll of Provia because I had become accustomed to using the light meter in my camera for print film. The next few rolls I made sure to purposefully underexpose by a half or a full stop (according to the meter), and the results were much better. Scanning them with a Coolscan V, I found that a lot of detail can be hidden in the dark areas. Using the curves tool in Cinepaint (derived from The GIMP), I could really make quite a lot of hidden detail appear out of the dark.
:Still, the point should be made that you expose print film for the shadows and expose slide/digital for the highlights. Print film can handle being overexposed (sometimes quite a lot) without losing detail in the highlights, whereas slide and digital can't. Slide film goes transparent and digital maxes out. --Imroy 12:05, 24 October 2006 (UTC)
replies: text: This is one area where Cinepaint (i.e. the 16-bit Film Gimp) should score over the ordinary Gimp, which only has 8-bits. Highlight and shadow detail are compressed into narrow ranges at the ends of the scale, and "stretching" this will exaggerate and (possibly) show up quantisation (i.e. loss of graduation/information). Fourohfour 17:16, 3 November 2006 (UTC)
thread_title:  Slide film 

message: Unfortunately, there doesn't seem to be that much information out there about Fred Archer's part in the creation of the zone system. Fred Archer is definitely *not* Frederick Scott Archer; the latter died in the 1850s. I came across one comment that was only available via the Google cache. It suggested that Fred Archer was working at a college in Los Angeles and published a series of articles in U.S. Camera during the late 1930s, these forming the basis of the zone system.
I added it to the Fred Archer article. Perhaps it should go here too? Fourohfour 16:56, 3 November 2006 (UTC)
thread_title:  Fred Archer's role 

message: According to Ansel Adams' Basic Photography series book 'The Negative' in chapter four, there are eleven zones in the Zone System.  This among other facts that I edited on this article in the past are incorrect information.  However those who wrote this article will do no research on my edits and simply restore the faulty information.  Someone wanting to use wikipedia as a source for learning the Zone System will fail because of the lack of research that goes into the articles that appear on the database.  I cannot take part further in misinformation for the sake of self input.  Sorry. -- 13:27, 2007 Apr 3 (UTC)
:Yeah, I have The Negative here with me at the moment, borrowed from the local library. There are definitely eleven zones - 0 through to X. So not only will the text have to be changed, but the graphics too. I'll see what I can do. --Imroy 16:32, 16 April 2007 (UTC)
replies: text: Ok, I've gone and made the necessary changes. I made my own gradient graphics in The GIMP and uploaded them. I replaced three images in the article with tables since solid colour boxes can be easily accomplished by setting background colours. The downside is that the tables are not the same size as the images and look a little disjointed. Perhaps they should all be replaced by SVG diagrams. I also fixed up the text to refer to eleven zones, not ten, and some other references to certain zones and ranges. I think it's correct now. --Imroy 10:12, 17 April 2007 (UTC)
thread_title:  There is errant information in this article  

message: Subject Brightness Range (more properly, Subject Luminance Range, though the acronym is still usually SBR) is an alternative term for “dynamic range” or similar measures of scene luminance, but it is not synonymous with Zone System. JeffConrad 07:38, 31 August 2007 (UTC)
thread_title: Subject Brightness Range

message: It seems reasonable to remove the dynamic range claim for current digital SLRs, because no one has cited a reliable source despite the long-standing “citation needed” flag. However, the bit depth of digital capture really has little do with the exposure range, so it it doesn't belong in this section. The paragraph about digital dynamic might benefit from additional information about the capabilities of current digital cameras, but any claims should cite reliable sources.
I appreciate the attempt to trim some of the wording, but it is far from established that HDRI is the proper term for a combination of two different exposures to capture a high-contrast scene. The citation of Flickr in the HDRI article is not a reliable source by Wiki standards. The HDRI link was previously removed from the Digital photography section here because of that article’s minimal relevance to the Zone System, and this was apparently acceptable to the major contributors to this article. I don’t think the link should be restored without consensus of at least a few other editors. JeffConrad 00:33, 16 September 2007 (UTC)
thread_title: Digital photography

message: It's an interesting link, but the text added to the article reads like a commercial pitch. Anyone else feel the same way? In any event, it needs a bit of copy editing. JeffConrad (talk) 23:39, 12 December 2007 (UTC)
replies: text: It does read like a commercial. The software sounds interesting, but it doesn't appear to be notable, and the text is not written in an encyclopaedic style. I also have my doubts about the second paragraph, concerning single-exposure HDRI. --Imroy (talk) 01:35, 13 December 2007 (UTC)
thread_title: Link to LightZone

message: I would like to add a small section describing how the histogram of a digital image can be used to enable the photographer to work with the zone system, both at the capture and image manipulation stage. The section will be added in late March if there are no objections.
Manamarak 00:04, 25 February 2008 (GMT)
:Be aware that Wikipedia is not a manual, guidebook, or textbook. Giving information and general descriptions of techniques is fine - a step-by-step guide is not. And it should have one or more good sources. If your proposed section meets these requirements, I have no objections. --Imroy (talk) 18:38, 11 March 2008 (UTC)
replies: text: This also smacks of original research. The proposed addition (or a summary) probably should be discussed here before being added to the article. That said, the same probably should have been done with some other material in the article. JeffConrad (talk) 21:31, 11 March 2008 (UTC)
thread_title: The zone system and Histograms

message: :Feel free to state your position on the renaming proposal by beginning a new line in this section with *Support or *Oppose, then sign your comment with ~~~~. Since polling is not a substitute for discussion, please explain your reasons, taking into account Wikipedia's policy on article titles.
*Support.  What's to debate?  It's a proper name, per Adams (the best authority).  The page should be renamed accordingly. Hertz1888 (talk) 02:35, 22 March 2010 (UTC)
thread_title: Survey

message: In the article: Use of the Zone System with color film is similar to that with black-and-white roll film, except that the exposure range is somewhat less, so that there are fewer zones between black and white. As well as I know it, color negative films have a lower gamma (contrast) such that they have more latitude (exposure range) than black and white films. Printing papers have the opposite, but this requires accurate exposure at print time. The mask on C41 films reduces the range somewhat, but I believe that there is still more than B&W film. The sensitivity charts for Kodak film are on their web site. Gah4 (talk) 21:03, 2 December 2015 (UTC)
thread_title:  Gamma 

message: worked out by Fred Archer and myself at the Art Center School in Los Angeles,  It seems that the school change name in 1965, so the quote is correct.  Would it be useful to Wikilink to the school's page?  Gah4 (talk) 04:14, 25 October 2016 (UTC)
thread_title:  ''worked out by Fred Archer and myself at the Art Center School in Los Angeles,'' 

message: The shades of grey used in the article don't look right to me.
What you point at with the light meter → what the meter will give you according to the article:
Scene area in zone V → exposure stops to use
Scene area in zone III → exposure stops to use + 2
This makes sense. If you point the meter to an area that's darker than the meter expects, it will give you a higher exposure than you should use.
Let y = Y / Y₀ for some reference grey Y₀; m(yV) is what the meter needs to give you for consistent results.
yV	yd~	N~   	m(yV)
1 	1  	f    	m₀
2 	1/2	f/1.4	m₀–1
4 	1/4	f/2  	m₀–2
8 	1/8	f/2.8	m₀–3
If the scene emits 8 times as much, the diaphragm area needs to be 8 times smaller, the diametre about 2.8 times and this is 3 stops.
So m(yV) = m₀ – ²log yV where m₀ depends on exposure time, film and optics.
Combining this with our starting point and substituting, we get:
m(yIII) = m₀ – ²log yV  + 2
but also = m₀ – ²log yIII
m₀ – ²log yIII = m₀ – ²log yV  + 2
²log yIII = ²log(yV / 4)
yIII = yV / 4
So the zone number Z(y) should be ²log(y) + Z₀ where Z₀ is the zone number of the reference grey. For example, if the reference grey is in the middle of zone V (YV = Y₀) you'd get ²log(Y₀/Y₀) + 5 = ²log 1 + 5 = 5. If YV = 2Y₀ you'd get Z(YV) = ²log 2 + 4 = 5 and of course Z(YVI) = ²log 4 + 4 = 6 and so on.
If we assume that all the tones in zone X are completely blown out but those in zone IX are not, it would follow that:
Z(Yw / Y₀) = 9½
²log(Yw / Y₀) + Z₀ = 9½
Z₀ = 9½ – ²log(Yw / Y₀)
Z(ȳ Yw / Y₀) = ²log(ȳ Yw / Y₀) + 9½ – ²log(Yw / Y₀) = ²log(ȳ) + 9½
ȳ = 2Z(ȳ Yw / Y₀) - 9½
So the geometric mean shades in each zone should be:
　0　　I　　II　　III　　IV　　V　　VI　　VII　　VIII　　IX　　X　
You might consider these tones quite dark, especially if you thought the tones presently used in the article were correct, but consider that VIII and IX are bright as snow. Snow is quite bright. Have a look as this skier: https://etsy.com/listing/573318057/snow-skier-skiing-vintage-photo-print Using a colour picker, avoiding the highlights on the right of his face and the dark shadows on the left, I get an sRGB brightness value of 110 or thereabouts: 　　 That falls somewhere between shades VI and VII on the scale above, right where the article says it should.
Of course, when developing a picture you can opt to make it brighter if it doesn't contain snow. But the fact remains that the luminance ratio between the zones should still be 2 and this isn't remotely true for the shades presented in the article.  — Preceding unsigned comment added by 77.61.180.106 (talk) 16:14, 26 March 2021 (UTC)
thread_title:  I think the shades are wrong 

message: Test background to make checking for colour bleed easier.
Full Tonal Gradation
;height:3em>
Eleven-Step Gradation
;height:3em>
The Zone Scale (on dark background)
0	I	X
End test background. 77.61.180.106 (talk) 12:07, 29 March 2021 (UTC)
replies: text: It seems that there is a problem with the last two pictures. At least on my computer and when downloading the article as a PDF, the graphics are not rendered and the rendering commands are displayed instead. 78.116.155.233 (talk) 21:40, 31 October 2022 (UTC)
thread_title:  Creating new graphics for the article 

message: In The Negative, I found a glaring error in the application of the inverse square law. In the passage where he talks about the appearance of sheets of paper in a dark room with a window, Adams takes the distance in the law to be the distance to the window whereas in reality the relevant distance is the distance to the sun. This means that the inverse square law is going to yield essentially a constant. It's fairly easy to replicate Adams' setup and experimentally verify this and I encourage you to do so. Adams either was imagining the situation – wrongly! – or he used a small light source such as a light bulb, but in that case I don't know why he would have felt the need to change the light source in the text, as windows don't behave like light point lights in the slightest. I don't think Vermeer would have slipped up like this.  — Preceding unsigned comment added by 77.61.180.106 (talk) 10:18, 29 November 2021 (UTC)
replies: text: If Adams was referring to a sheet of paper illuminated by direct sunshine through a window then you would be correct. I have not read the source, but it seems likely that Adams was referring to diffuse light reflected from the surroundings outside the window. Verbcatcher (talk) 16:19, 30 November 2021 (UTC)
replies: text: Even then he would not have been correct, because in that case the average distance to the diffusely reflecting surroundings in question and the apparent size of the window as seen from the sheet of paper would be the important factors. The more I read that paragraph, the less sense it makes.  — Preceding unsigned comment added by 77.61.180.106 (talk) 18:03, 1 December 2021 (UTC)
thread_title:  Inverse square law error