The Zone System versus Digital cameras dynamic range

[thiago_silva]

Hi all,

I've been reading about the famed Zone Systems lately, and it is mentioned many times that the original system had ten zones, but that for certain types of filme the number of zones is reduced, due to the reduce dynamic range.

I wonder then, how do you know the dynamic range of your digital camera, then, in terms of f-stops? Is it specified somewhere in the manuals, is there a "standard" or you have to determine it by testing?

Sorry if this post makes no sense, but I'm just a begginer starting to piece together the theories behind photography.

Thanks,

 

[ewelch]

The problem with the Zone System is that people think it's some formula for taking photos that is 1-2-3 simple. it's not. It was designed as a way of teaching sensitometry to photo students. It grew as one of its two creators (can't remember the other guy), Ansel Adams, popularized it by creating a series of books based on it. With film, it's a way of describing how film and light and chemistry interact, and standardizing it to give the photographer control over the image. With negative film, you have more control than with slide fim, but the principles are the same. The problem with color flim is that you really can't modify development like you can with black and white. So the Zone System becomes way, way, way more complex if you want to try to use it with slide film, for example.

With digital camears, you're limited to using the parts of the Zone system that applied to something like slide film. But with way more lattitude. For most people, once you understand the basic principles of sensitometry, then you know what you need to make photos with any camera and film/sensor combination out there. The Zone system isn't some magical incantation that makes better photos. It's simply an understanding of how light creates images.

Its good to know. But put down the books, and go out ans shoot based on what undrestanding you gained from it that applies to what you're doing now.

--
Eric

Ernest Hemingway's writing reminds me of the farting of an old horse. - E.B. White

 

[donaldsc]

One other thing - if you are going to use the zone system, you will need a digital camera that can work in full manual mode. I would guess that you would also need an exposure meter, probably a spot meter model. The exposure meter in your digital camera is probably nto flexible enough.
--
Don

 

[Tim the Grey]

Occasionally I will Zone Meter a scene. Spot meter, and check bright, and dark areas. I'm looking, if at all possible, to keep it all within 5 stops. If not, you then have to work out which you can afford to lose, or how to lighten up shadows!

I tend to work as though I'm using slide film, which I did happily for 20 odd years.

Zone is great for Large Format single plate negs, but not quite so useful for 35mm roll film. You dev the WHOLE roll the same way. Zone was designed to allow specific push/pull processing of a neg to standardize printing...

Adapt it, don't take it as gospel!

Tim
--
http://catmangler.smugmug.com/

 

[tex]

...the part of the zone system most applicable to the digital age: previsualization.

we have no easily available data at this time on the range of sensors available in various cam models AND any internal, usually proprietary, algorithms for the processing of the sensor capture---even given shooting in raw. thus we have no baseline [as has been pointed out in some other threads} to do our sensor 'sensitometry', if you will.

but the previsualization process is still viable, even given the roughness of the approxiamtion lacking the baseline sensor data. this is the 'art' part and still well worth learning.

 

[Stephen Schwartz115733]

First of all, the zones have nothing to do with digital vs film. The zones simply describe the intensities of light in terns of powers of two. ZIII is twice as bright as ZII, Z!V is twice as bright as ZIII,

This is obviously true regardless of how you will record an image.

BUT, the zone system goes on to teach you how these zones will be transformed as a recorded or displayed image. So, to use it, you need to learn that when the shadows are two zones darker than the vase in the scene, the medium you are going to use will/will not let you get the brightness you want to use to represent the original scene.

BUT:

1. like slides, digital is usually color. The ZS has never been redone to deal well with color contrast. This is not simple densitometry because color contrast is not dependent on tone as well as intensity.

2. the huge range of control in a digital process goes to a far galaxy beyond what Ansel could do with film and paper.

My recommendation:

a. EVERY photographer, every serious photographer, needs to learn to "see" in zones as a way of knowing how her equipment will make images.

b. a. meter is OK, but with training and experience most of us can "see" ion zones.

c. zone exercises are a good thing to do with a digicam. Use the built in meter to measure light and then see how well you can do in turning this into an image. The result?

i. you will learn about the "toes" .. the difficulty in getting a good image in the shadows or the highlights. Even wi Pshop, you can only make an image IF you have recorded the detail,

ii. as above you will begin to understand the amazing role color/tone plays in imaging.

iii. with practice, you will learn that you do not need a camera to see . This is sometimes called :zone buddhism."

For a wonderful introduction, see if you can fins a copy of Minor White's pamphlet/book .. The Zone System Manual.
--
Stephen M Schwartz
SeattleJew.blogspot.com

 

[thiago_silva]

my interest in the Zone System is probably because, as a scientist, I tend to like anything that resembles the "scientific method". And by the same reason, I always want to know what is behind something, instead of just taking it for granted. I would never be happy to know that my camera takes pictures, period. I would have to know how.

But I know that at the utmost level, photography is art, and not science. Eventually, I'll conciliate both.

I work with satellite images, so I tend to think a lot in bits and digital numbers. A 16bit image can hold more information than a 8bit image. Period. But when the Zone System starts to describe it in terms of how many f-stops a film can record, I'm not sure how to translate it to digital.

 

[Skylane]

The is little doubt that understanding the zone system will improve anyone's photography.

I would suggest that a camera with a live histogram and learning how to use it (numerious articles on the web - google it) will help a beginner or average photog improve their exposure's quicker. It is an excellent tool that only digital camera's (a few hand held exposure meters also have them) can provide. A picture is worth a thousand words, right?
--
Charlie

 

[thiago_silva]

Found most of the answers I was looking for from here:

http://www.luminous-landscape.com/tutorials/understanding-series/understanding-histograms.shtml

But still, thanks everyone for the answers, the insights you gave me are priceless and beyond any tutorial.

 

[Ian Yаtes]

a live satellite image?
or is that just a Hollywood myth?

Ian

--

 

[JLK]

Try working with your photos in Lightzone, by Lightcrafts (dot com). They have a couple versions that come with free trial periods. Their editing system is really unique, and I like it for many reasons, but their Zonefinder/Zonemapper controls (for adjusting contrast and levels) is more intuitive (for me) than curves in photoshop. The fact that you can apply these to local regions easily throught their masking system makes for some very fast processing---and in developing a raw image through to print, this makes a big difference.

--
Jim

 

[donaldsc]

The program looks really intriguing. However, I have never heard of it. Do you use it as your sole program? How is it in handling B&W - I am scanning a large number of old B&W prints and they are hard to work with.
--
Don

 

[photophool]

Try this. Using a tripod and a well lit wall and camera in manual mode:

Take picture a picture, correctly metered.

Take another one stop over exposed. Then another 2 stops over, etc. until the picture is totally 'white' (255,255,255)
Now do the same but in under exposed direction until 0,0,0.

Count the number of pictures from 0,0,0 to 255,255,255

Viola! Your camera's dynamic range, number of zones. Notice where the correctly metered picture falls. Use this to add exposure compensation, after you learn how to pre-visualize and where you want the metered object to fall.

--
Appreciating the gifts you have been given is the blessing.

 

[Mike Worley]

Apologies to Spinal Tap.

 

[rgmoore]

With digital camears, you're limited to using the parts of the Zone
system that applied to something like slide film.

That's not quite true. You have to adopt something like the approach that you'd take when shooting with slide film, by metering for the highlights and controling shadows in development rather than the other way around, but that doesn't mean that you're in some sense limited in the application of the system.

If anything, digital makes some aspects of the Zone system easier because you're free to reprocess your raw file as many times as you like. While it's still possible to make exposure mistakes, you're protected against the equivalent of development mistakes. You can also fine-tune development in a way that was completely impossible with film. The biggest problem is that you have too much freedom, so that there's a strong temptation to keep fiddling instead of getting a good picture an moving on to the next one.

 

[lightp8nter]

Hello Thiaga:

Try this link for quick practical review.

http://www.digitalsecrets.net/Sony/AdvancedKnow.html

--
Nate Parker



http://lightp8nter.smugmug.com/gallery/51256/1/1784370/Medium

 

[Skylane]

Another take on this subject (last para is the kicker)

Some people think of digital imaging as solid state film. This isn't the case. The following explanation by Bruce Lindbloom may help you understand what's going on with the above technique... (expose to the right)

For film based photography, the highlight end of the scale is compressed by the shoulder portion of the D/log E curve. So as brighter and brighter objects are photographed, the highlight detail gets gradually compressed more and more until eventually the film saturates. But up until that point, the highlight compression progresses in a gradual fashion.

Solid state sensors in digital cameras behave very differently. As light falls on a sensor, a charge either accumulates or dissipates (depending on the sensor technology). Its response is well behaved right up until the point of saturation, at which time it abruptly stops. There is no forgiveness by gradually backing off, as was the case with film.

Because of this difference, setting up the exposure using an 18% gray card (as is typically done with film) does not work so well with a digital camera. You will get better results if you set your exposure such that the whitest white in the scene comes close to, but not quite reaching, the full digital scale (255 for 8-bit capture, 65535 for 16-bit capture). Base the exposure on the highlight for a digital camera, and a mid-tone (e.g. 18% gray card) for a film camera.

--
Charlie

 

[thiago_silva]

I'm not sure what you meant by live. I assume it is like an image available immediately and/or continuously.

There are some systems, like MODIS, from which images are available a few hours after being acquired, for fire detection purposes. But for most scientific and commercial satellites, it takes some time until the satellite images a good portion of the earth, then flies by a receiving station and dumps everything. Then it goes through some pre-processing and cataloging, before being available to the public. Which usually take a few days.

Another problem is, there are two kinds of satellites: geostationary and polar orbiting. The geostationary follows the earth rotation and always sees the same portion of earth. The polar orbiting circle from pole to pole, imaging the whole earth as it spins, much like peeling an orange.

So, to have a live feed from a given area any time you want, you would have to have many geostationary satellites covering the earth from many perspectives. It's technologically possible. But if it exists, its military, and we never know for sure what they have. Until (if) they decide to declassify it twenty years later or so.

a live satellite image?
or is that just a Hollywood myth?

Ian

--

 

[thiago_silva]

JLK,

Actually Lightzone is what aroused my interest in the zone system, especially beacuse I tried tu use it and had not much clue of what was going one. But again, coming from the remote sensing field, histograms and curves are very natural to me, what is probably why I didn't quite get the ZS at first.

Try working with your photos in Lightzone, by Lightcrafts (dot
com). They have a couple versions that come with free trial
periods. Their editing system is really unique, and I like it for
many reasons, but their Zonefinder/Zonemapper controls (for
adjusting contrast and levels) is more intuitive (for me) than
curves in photoshop. The fact that you can apply these to local
regions easily throught their masking system makes for some very
fast processing---and in developing a raw image through to print,
this makes a big difference.

--
Jim

 

[thiago_silva]

Good idea! I'll try that!
Cheers!

Try this. Using a tripod and a well lit wall and camera in manual
mode:

Take picture a picture, correctly metered.
Take another one stop over exposed. Then another 2 stops over, etc.
until the picture is totally 'white' (255,255,255)
Now do the same but in under exposed direction until 0,0,0.

Count the number of pictures from 0,0,0 to 255,255,255

Viola! Your camera's dynamic range, number of zones. Notice where
the correctly metered picture falls. Use this to add exposure
compensation, after you learn how to pre-visualize and where you
want the metered object to fall.

--
Appreciating the gifts you have been given is the blessing.