Book Review - Digital Zone System

[Mark D Segal]

I got delivery of this book this morning. So far read about 1/2 of it. The first part mostly covers digital photography in general with descriptions of how aperture/shutter/iso works. It is well written but not sure if it is needed except to add as a filler. I have got to the nub of the book, the zone system. I was expecting to see the usual advice about visualising the scene, dividing the scene into zones adding/subtracting EV before pressing the shutter and exposing accordingly. That is not what the book is about at least what I have read so far. It is about applying the zone system to a captured image and using LR/ACR sliders in conjunction with the zone system. An interesting idea and the rest of the book will be an eye opener as to how it applies. The author isn't a fan of ETTR so fans so should be aware of that.

Based on what I see of your work on your website, you don't need this book. Some truly impressive photography there.

Turning to the advice you provide, let me put it this way: as you no doubt understand, ETTR isn't question of whether or not one is a "fan". ETTR is solidly based physics and mathematics. More data is conducive to making better quality photographs and you get more data by ETTR without clipping necessary highlight detail. If the author of that book doesn't understand and convey this message, he doesn't understand digital imaging.

[stamper]

The author has named this book the Digital zone system which means that Ansel Adams springs to mind. I quickly looked at the latter half of the book - not in detail - to see where he was going with his ideas. The connection between the zone system and the book is imo tenuous to say the least. HDR is recommended as part of the process as a possibility. He could have named the book ... Luminousity masks and advanced processing .... and it would be nearer the mark imo. I expected when I was halfway through the book that the different zones would have been tied in with the sliders in ACR/LR to provide a method of processing an image but that idea wasn't on the cards. Anyone who has left PS behind in favour of using LR/ACR for processing an image will find little in the book to interest them but if they still like sitting for a while with PS then it interesting if they have the patience. As stated a connection between the zone system "proper" and this book is tenuous to say the least.

[Mark D Segal]

Thanks very much for the heads-up. I too don't believe in complicated solutions when easier ones work just as well - if not better.

[stamper]

Based on what I see of your work on your website, you don't need this book. Some truly impressive photography there.

Turning to the advice you provide, let me put it this way: as you no doubt understand, ETTR isn't question of whether or not one is a "fan". ETTR is solidly based physics and mathematics. More data is conducive to making better quality photographs and you get more data by ETTR without clipping necessary highlight detail. If the author of that book doesn't understand and convey this message, he doesn't understand digital imaging.

Mark thanks for the praise. I am open to "new" ideas. He states that ETTR is only useful if the information captured is within the capabilities of the sensor. In other words not a high contrast scene which makes sense. If someone had taken an image using ETTR then there will be a disconnect with it and the zone system he proposes. The book is a very interesting read if someone could borrow a copy. He doesn't dismiss ETTR out of hand but it doesn't fit comfortably with his ideas. It is a niche book that fits in somewhere along with all of the other ideas of exposing and processing.

[stamper]

Thanks very much for the heads-up. I too don't believe in complicated solutions when easier ones work just as well - if not better.

That is a very good summing up of the book.

[digitaldog]

The author isn't a fan of ETTR so fans so should be aware of that.

What's the justification?

[stamper]

I think I know what you are getting at. If so my reading of the book is that he wants an image that someone who likes exposing for a mid tone would capture. The midtones around the 18% mark and the dark tones near the bottom end and the light tones near the top end. You then mask off different areas with luminousity masks and similar selections  and then apply level or curves to each mask. If you have the midtones further up from 18% then you can't employ his ideas? That is my reading of it but somebody more knowledgeable might chime in with a better explanation?

[RFPhotography]

Stamper, I think to say that I'm not a 'fan of ETTR' is misstating things.  I'm not an ETTR zealot.  I recognise that ETTR has benefits but also limitations.  Both are outlined in the text. 

As far as your expectation that I would have talked about adding/subtracting EV from a meter reading to get a proper rendering of a certain area of a scene (typically a shadow area), that thinking isn't relevant with digital as it was with film.  Particularly for one who employs ETTR.  In point of fact, the 'traditional' Zone System methodology of placing the important shadow detail can work in conflict with ETTR depending on the drange of the scene and where that shadow is placed.  It isn't relevant because, unlike with film where you only had control of highlights in development, with digital we have control of the entire brightness range which is why ETTR works.  We can expose right, capture more light, improve SNR and then adjust the RAW capture to pull those shadows back to where we want them. 

[stamper]

Bob are you the author of the book? If so I didn't realise that. However I stand by what I stated. I am not a book reviewer so there isn't a polished review in my posts only a gut reaction. I think that most people seeing the book will think that they are getting - if they don't look too close - an updated tome about the digital zone system. I have other books that think that the digital zone system is relevant. Lee Varis

http://www.amazon.co.uk/Mastering-Exposure-System-Digital-Photographers/dp/1598639870

makes a case for it and Michael freeman

http://www.amazon.co.uk/Perfect-Exposure-Professional-Capturing-Photographs/dp/1905814461

shows passing interest in it in this book.

Lee Varis recommends editing in the Lab colour space as a follow up to using the zone system.  Something he was slated for in this forum about a year ago. Luminousity masks and selections aren't new so most photographers who are proficient in PS will have been doing this in the past but now use LR/ACR for an easier life.

[RFPhotography]

And that's OK.  I was just explaining my viewpoint.  :-)  Something else that may account for the difference in viewpoints/approaches is that Varis is not a fan of ETTR. He feels it's good theory but bad in practice because the camera histo isn't accurate enough to make it an effective method of exposure.  He also feels that it doesn't indicate whether the histo is accurate for the subject - something I also discuss.  He expresses this view in his book 'Skin'.

[Guillermo Luijk]

Without reading the book it's unfair to judge. However I have to say that in a book about the digital zone system I get a bit scared when looking at this:




An author who associates the 128 tone to zone V, should be aware that 128 means a very different grey tone depending on the gamma curve of the colour profile used. And in fact, none of the most common colour profiles has 128 as a middle luminance level (a perfect perceptual middle grey should be 119 in sRGB, 118 in Adobe RGB and 100 in ProPhoto RGB in a 0..255 range):




Regards

[stamper]

And that's OK.  I was just explaining my viewpoint.  :-)  Something else that may account for the difference in viewpoints/approaches is that Varis is not a fan of ETTR. He feels it's good theory but bad in practice because the camera histo isn't accurate enough to make it an effective method of exposure.  He also feels that it doesn't indicate whether the histo is accurate for the subject - something I also discuss.  He expresses this view in his book 'Skin'.

He has a point about the accuracy of the histogram because it is a jpeg rendering. Extra work has to be done by the photographer with respect to learning if he wants to match the jpeg histogram and a raw histogram. From my experience there is about a 2/3 stop difference between the two and that is a little subjective and not entirely accurate. If someone wants to try the luminousity mask approach with regards to processing an image then would it be better they captured an image without ETTR being employed? I will have to read the book again thoroughly to fully understand the thrust of it.

[stamper]

Quote Guillermo

An author who associates the 128 tone to zone V, should be aware that 128 means a very different grey tone depending on the gamma curve of the colour profile used. And in fact, none of the most common colour profiles has 128 as a middle luminance level (a perfect perceptual middle grey should be 119 in sRGB, 118 in Adobe RGB and 100 in ProPhoto RGB in a 0..255 range):

Unquote

Michael Freeman in his book Perfect Exposure deals with this issue in terms of percentages and refers to it as a brightness scale. The scale is relative to F stops. He refers to the 128 tone as 50% and states that .... most exposure decisions don't need a high degree of precision. I think this is practical. Obviously reading what he has written would be best.

[Guillermo Luijk]

Michael Freeman in his book Perfect Exposure deals with this issue in terms of percentages and refers to it as a brightness scale. The scale is relative to F stops. He refers to the 128 tone as 50% and states that .... most exposure decisions don't need a high degree of precision. I think this is practical. Obviously reading what he has written would be best.

But if you are using a colour profile with a low gamma (e.g. the 1.8 gamma used in standard ProPhoto RGB), a 128 tone is much brighter than a middle grey (see my figure above). So I think having the 128 figure as a reference to middle grey is not valid.

[stamper]

Searching for complete "accuracy" in this subject is possibly futile and as Michael Freeman states

most exposure decisions don't need a high degree of precision.

From a practical point of view do what is "best" when using the camera and import to LR/ACR and adjust to taste?

[stamper]

In the book Digital Zone System there is an explanation of the weighting with respect to center weight metering which I haven't read before and was imo very interesting and I will read up on it. There are other nuggets of interest that are valuable which may not be directly connected to the main point of the book, even if you think you are advanced with your knowledge of photography. 

[digitaldog]

An author who associates the 128 tone to zone V, should be aware that 128 means a very different grey tone depending on the gamma curve of the colour profile used.

Yes and it's a pet peeve of mine too. Like when someone says "I don't use Adobe RGB (1998), I use RGB" or "Adobe RGB has more colors than sRGB".

[Frankomatic]

Has anyone tried the DZS photoshop actions in earnest?

Anyone care to respond to the OP's second question?

Am curious to know in what ways they might differ from Tony Kuyper's luminosity mask actions.

[Mark D Segal]

He has a point about the accuracy of the histogram because it is a jpeg rendering. Extra work has to be done by the photographer with respect to learning if he wants to match the jpeg histogram and a raw histogram. From my experience there is about a 2/3 stop difference between the two and that is a little subjective and not entirely accurate. If someone wants to try the luminousity mask approach with regards to processing an image then would it be better they captured an image without ETTR being employed? I will have to read the book again thoroughly to fully understand the thrust of it.

The relationship between the in-camera histogram and the histogram of the raw image opened in LR or ACR differs depending on the camera model. Once you understand the relationship for your camera, you know how to interpret your in-camera histogram. This needs a bit of up-front trial and error, but isn't by itself a reason for complexified image editing.

[digitaldog]

The relationship between the in-camera histogram and the histogram of the raw image opened in LR or ACR differs depending on the camera model. Once you understand the relationship for your camera, you know how to interpret your in-camera histogram. This needs a bit of up-front trial and error, but isn't by itself a reason for complexified image editing.

Kind of like the old days when you'd shoot a Polaroid of your strobe lighting, then extrapolate in your mind (after shooting lot's of 'roids') what the transparency would look like.

Today I just prefer to ignore the JPEG histogram. But I believe with time, one could use it as a lesser reliable Polaroid in respect to exposure and clipping.