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Will Zone lll always be Zlll?


jim_gardner4

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<p>I have been doing some film tests over the last week and I am getting confused with the results.<br>

I am trying to get Zlll by measuring a subject and underexposing by 2 stops. The thing is if the subject is in sunlight it records with more density on the neg than if it is in shade. Surely the brightness of the scene or the amount of light falling on it should make no difference nor should the time of day i.e. middle of the day or evening light?<br>

The spot meter is callibrated, film, developer, dev times, camera, lens and temp are all the same and shutter speeds are not long enough for reciprocity failure to come in to it.<br>

I always assumed that a subject could be recorded as any zone from 0 to X if exposure was set at 5 stops under ---- 5 stops over the meter reading regardless or light falling on it. Am I wrong?<br>

I meter with a Sekonic L-508 1 degree spot meter.</p>

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<p>It is going to depend on the subject. If it is a piece of flat board, like gray poster board, then it should be the same. You may not be metering at the same angle as the camera lens and you may also have glare in the sun you aren't allowing for--or in the sahde for that matter. the closer to the subject, the more likely glare is a factor.</p>
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<p>Jim, Yes, Zone III is always Zone III, provided you have metered it correctly. The hardest part of using the Zone System is being able to visualize what a particular film looks like. Zone III is always going to be Zone III, but different films have different latitudes, and that's where the system might need some adjustment by today's standards.</p>

<p>As Tony says, you first need to get your Zone V point. As you get better at visualizing your image, you'll know where V should be, or where you would like it to be. I found an incident meter to be a help at first. Once I knew where Zone V was, according to the incident reading (or gray card, if you like), then you can use your spot meter to figure out which parts of the subject fall on that Zone. Then you can find which zone is III.</p>

<p>The problem with 0 to X is that some films have a bit more latitude than others, so the adjustment you have to make is not where 0 or X is (because those are well defined), but what each zone between represents. That's why, if I need to use the Zone system, I stick to film and development methods that are well suited for the system. Otherwise, I'm more inclined to use a stand development methodology for developing the film, or use a different developer altogether if I'm trying to compress values.</p>

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<p>What Michael said. But light falling on a scene can read or record brighter or darker from bright sun to shade etc... <br>

I'd be interested to know how you are stopping down. Shutter speed or aperture? Vintage leaf shutter or modern focal plane etc...? Use the aperture to stop down. Shutter speeds amy be and probably are at least a third stop off. <br>

It sound to me like you are not doing the test right. The book says to make your tests in open shade, not sunlight, Or under cloud cover, in other words, not in direct sunlight ! <br>

Might also be helpful to tell folks what film, what developer etc... </p>

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<p>That all makes sense but am I right in assuming I can look at any scene, choose the darkest area in which I want to retain printable detail/texture on the neg, then take a spot reading from it and underexpose by 2 stops to place it on Zlll (assuming I am using the same film, developer etc I always do) and the result will be Zlll regardless of lighting conditions?</p>

<p>For example, a scene has a light gray wall in it in sunlight. I meter the wall and close down 2 stops and the neg have a density that will print zone lll (assuming for some reason I wanted to place the wall on Zlll). On the next frame <em><strong>but same scene</strong></em> etc, I meter off a dark grey rock in the shaded part of the scene and close down 2 stops and that part of the neg should show <em><strong>exactly the same density</strong></em> as the white wall in the first shot shoulnt it?<br>

I have been using this method for ages but for some reason my zone lll negative densities are not always the same.<br>

Many thanks so far.</p>

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<p>The answer is yes. Whatever you meter off is (should) be interpreted by your meter as Zone V. If your negative densities vary a great deal I would look for other causes. Incidently, different lenses and different exposures on the same lens will not always give you the same Zone V density. I have checked this many times.</p>
Tony Evans
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<p>Jim,<br>

Let me expand. Take a flat evenly lit area (sidewalk, wall, deck, etc) and meter for Zone V. Now shoot several more but varying the f stop and speed to keep the same EV. Or, if you have multiple lenses, shoot another lens at the exact Zone V exposure. Develop and I will guarantee the densities are not exactly the same. Precise Zone shooting requires standardization of lens, aperture, speed, etc as well as the usual processing parameters.</p>

Tony Evans
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<p>SG, I am stopping down using the aperture in a modern leaf shutter (Zeiss Planar 2.8 80mm Cfi). Todays test done on fairly bright day (for England in January!) but the Zone lll subject was well in shade. Meter reading was f8 @ 1/8th sec, exposure made at f16 @ 1/8th sec.<br>

Fuji across 100, 120 film developed in ID11 1+1 for 10 minutes at 20 degrees C.<br>

While I understand some people may say I could get less grain etc with so and so developer, it is densitys I want to test at the moment and I usually get on well with ID11 and Across 100.</p>

<p>Test was done exactly as in the book i.e do a test print through blank film first to get first max black printing times for the paper (Ilford MG1V) then print all test negs at that time.</p>

<p>I should say the results are not miles out but today I am easily getting full speed from the film and other times I seem to need to rate at down to 50 ISO to get decent Zlll neg densitys.</p>

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<p>Tony mentions a phenomenon that can relate to inconsistent shutter speed and sometimes even a sloppy f-stop ring, if on a manual camera. I learned way back that you get more consistent f-stops if you always set them from the same position--that is either start wide open or closed all the way down. Moving an f-stop to the first position counter clock-wise and then the second clock-wise can introduce "slop" into the system--just a small amount of movement to get positive movement can make a difference in the actual f-stop.</p>

<p>Another issue is texture. If there is texture, then likely not all of it is the same brightness. In the sun, there can be small specular highlights and in the shade maybe not so much--depends on light angles and all. And then, the meter might react differently to color. Shade is blue, while sun is neutral. Zone VI, when it was a viable company, created modified Pentax spot meters that were supposed to eliiminate these color differences in the meters sensitivity.</p>

<p>By physics, they should be the same, you just have to allow for other factors sometimes.</p>

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<p>Fansinating. Can I thank you all for such informative and quick replies to my question. I have got lots of help from this site over the last couple of years and hope I have been able to help a few people a bit as well. PS does Photo.net ever organize a get together and if so, is anyone out there in or around north Bucks, England? Cheers, Jim.</p>
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<p>Jim, You happened to be using the very film that made me hedge my comments a bit. Acros' response is very different than Tri-X, and I don't find that Adams' zone system works very accurately with Acros. Acros has a much different tonal response, and you will get very different densitometry readings under various conditions.</p>
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<p>Jim, in strong sunlight, your scene has a greater dynamic range. Your Zone 3 meter reading requires a different adjustment to give you zone 3 in the print than it did with a low contrast scene.</p>

<p>Just remember, depending on the film and the range of the scene, a 2 stop adjustment won't always equate to a 2 zone adjustment... Zones are different from Stops.</p>

<p>What you are talking about, are rules of thumbs, which may work with certain films and are good as a starting point, but you need to learn how to adjust your techniques to compensate.</p>

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<p>Zone III is Zone III regardless of the lighting conditions; sun, shade, shadow or overcast. It is the first Zone where you will have easily discernable texture. I suspect that you are not always metering something that really should be in Zone III. That would account for your inconsistencies. You have to look at a scene and immediately pick out the area that should be in Zone III. I usually meter Zone III and then look at all the other Zones around it and see if they fit with the Zone III exposure. If they don't then I may have to apply N +/- 1 or 2 development. When I shoot black and white in 35mm, I carry three F2's with me, each loaded with bulk loaded film designated N-1, N, and N+1. That is really the only way to do the Zone system as it was intended when you are using roll film instead of sheet film.</p>

<p>I would suggest you get a book by Chris Johnson entitled "The Practical Zone System". It can be found on Amazon.com for about $20. It is an outstanding resource when it comes to the Zone System.</p>

<p> </p>

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<p>To use the Zone system fully. You must first take tests concerning the film, developing time and temperature. The len's ACTUAL shutter speeds and aperature. Also, the film batch. All these items can effect the negative's density. Find the resulting exposure, developing time, etc that gives a first noticable density in the neg. (This is without using a densitometer to make it easier.) This is the first zone . Then, you will have better results.</p>
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<p>Scott, the whole idea of the zone system is to learn how to place anything, whether it "should" be zone III or not, at zone III if that is where we want it to be--theoretically, exposing the sun at zone III should give the same density reading as exposing grass at zone III. The zone system is about densitometry and doesn't have any relation to where a value is in our visual reference, but to where we want it to be on a print and getting the necessary detail on the film to make it a zone III in that print that is not muddy.</p>

<p>Detail will be available on film well below what we need density wise for a great darkroom print. I have learned that a scanned negative works better when it is a bit thinner--as much as a stop overall--than what is ideal on the same film for a darkroom print. I apply the zone system in the same way, but I set my ISO differently depending on which I intend to do--although scanning is more likely than darkroom printing these days.</p>

<p>In fact scanning can really overcome a lot of ills, I have an image that was so underexposed that the film looks blank unless held to the light where the small amount of silver creates what appears to be no more than a latent image. When I scanned it, I actually got an incredible image, full tonal range and plenty of detail, that I used in my portfolio for years. It wasn't a perfect image, but had the "funky" look I wanted and some very nice colors.</p>

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<p>Use an incident meter. End of story. Spot metering is not simple and it's not foolproof. It's really good at measuring the delta between tones. It's not so good at measuring an overall good exposure. The incident meter does not lie. It measures the light hitting your subject, not the light being reflected back from it.</p>
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<p>So Frank, what do you do when you are standing in the sun and shooting something in deep, very deep shade that you can't get to? I think saying that spot metering is not good for overall exposure is really more a lack of knowledge of its use than anything else. Spot metering is not difficult and much easier with a handheld than trying to do it with the cameras spot function. It takes time to learn in any case, as it doesn't just spit out an answer, you have to actually do some thinking with it. But after 30 years spot metering, with but one issue, I think it is pretty reliable. I might wonder if an incident meter might have been a good thing in that one case, but I can think of many where it would have been useless.</p>

<p>I have no issue with incident metering and it is certainly easier and quicker and just as good in many situations, but let's not get carried away!</p>

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<blockquote>

<p ><a href="http://www.photo.net/photodb/user?user_id=79798">Frank Schifano</a> <a href="http://www.photo.net/member-status-icons"><img title="Frequent poster" src="http://static.photo.net/v3graphics/member-status-icons/1roll.gif" alt="" /></a>, Jan 25, 2010; 10:53 a.m.<br>

Use an incident meter. End of story. Spot metering is not simple and it's not foolproof. It's really good at measuring the delta between tones. It's not so good at measuring an overall good exposure. The incident meter does not lie. It measures the light hitting your subject, not the light being reflected back from it.</p>

</blockquote>

<p>That is utter nonsense Frank. An incident meter looks at the same thing a reflected meter looks does, it sums the light to Zone V. It cannot be used to determine Zone System. It does not take into account what the photographer wants to do with the image, it just gives an "average" Zone V exposure. Although it is certainly applicable in a wide range of applications, back lit subjects for example. Spot metering it not nearly as simple as taking an incident reading, but like everything else, it takes practice to properly use it. And it takes into account a lot of things that an incident meter cannot.</p>

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<p>Didn't say it wasn't reliable. It is, and I do know how to use a spot meter. Remember that there are a lot of folks out there without a lot of experience who think that a spot meter is the be all and end all of metering systems. And I didn't say it was totally useless. In fact it can be useful IF one knows how to use one and properly interpret the readings. </p>
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<p>"I don't find that Adams' zone system works very accurately with Acros. Acros has a much different tonal response, and you will get very different densitometry readings under various conditions."</p>

<p>My experience with Acros has been that it responds very nicely to increased or decreased development.</p>

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<p>" . . . For example, a scene has a light gray wall in it in sunlight. I meter the wall and close down 2 stops and the neg have a density that will print zone lll (assuming for some reason I wanted to place the wall on Zlll). On the next frame <em><strong>but same scene</strong></em> etc, I meter off a dark grey rock in the shaded part of the scene and close down 2 stops and that part of the neg should show <em><strong>exactly the same density</strong></em> as the white wall in the first shot shoulnt it?"</p>

<p>Maybe not. What's described there is a two-stop shift. That's only one part of getting to the answer. Now, if you had metered off a gray card first, and determined the difference between the reflectiveness of the gray card and the reflectiveness and tone of the metering target <em>and also taken that into account</em>, then the answer could be yes.</p>

<p>Reflectiveness is the key. The 18% gray card readings are based on that reflectiveness at a middle gray tone.</p>

<p>For example, water is a highly reflective subject that can show as a range of tones (from bright white to deep shadow)[to make matters worse, it can go from opaque to translucent to transparent based on camera angle and water properties]. Generally speaking, it's possible to approximate a good metering off of skin tones, green leaf vegetation, even rocks, based on experience. Yet, we do have subjects out there which have tones based on local color or reflectiveness which is greater or less than that 18% card.</p>

<p>To put <em>any subject</em> in Zone III, you would need to understand not only that you would want a two stop shift, but also understand <em>how much that subject differentiates from that standard 18% card's reflectiveness and tone</em>.</p>

<p>Take a wall, for example. When photographing that wall straight on, it'd be easy to figure up the answer. Now, say you wanted to photograph that wall at an acute angle, with the wall having say, vinyl siding or other smooth texture on it, and sunlight shining on part of that wall. Smoothness affects reflectiveness. Camera angle would start to count more because of reflectiveness and smoothness. In the case of a sharp angle against a long smooth daylight subject, I could come up with a variety of tones based on where I pointed that spot meter. It'd be plausible to go through all of the available tones based on targeting.</p>

<p><strong>The key to doing this in a controlled fashion is to understand the difference between what's standard and what's observed.</strong></p>

<p>If you begin your metering process with an incident reading, or spot off 18% card near the subject, and <strong>use that reading as a control</strong>, you can come to a sharper understanding of what's about to unfold. <strong>Then</strong> go ahead and meter the subject. <strong>Is there a significant difference?</strong> Sometimes there will be. If there is, take that into account.</p>

<p>Then compute the two stop shift.</p>

<ol>

<li>Incident or gray card reading to understand the light falling on the subject</li>

<li>Meter the subject to understand the subject</li>

<li>Compare the two to see if there is a significant difference & generate an adjustment if needed</li>

<li>Compute the tonal shift from average</li>

<li>Factor in any other exposure computations, like filter factors, to solve for exposure.</li>

</ol>

<p>Try those five steps and see if they de-bug your metering problems. Most of the time the control step is omitted because people get used to understanding the difference between the card and what they are normally photographing. But, to put <em>any subject</em> in the correct tone you would need to know both its properties and the falling light's properties. Then make your tonal shift adjustments.</p>

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<p>"To put <em>any subject</em> in Zone III, you would need to understand not only that you would want a two stop shift, but also understand <em>how much that subject differentiates from that standard 18% card's reflectiveness and tone</em>."<br>

I cant see it John. If I spot meter off any tone subject in any lighting conditions from the exact camera position and expose at the reading given by the meter, then I must get a middle/ 18%grey / zone v result surely? If I then underexposed by 2 stops wouldn't the resulting exposure give a Zone lll value in the print? That is assuming callibration etc etc have all been done.<br>

Is not the use of a spot meter onto a grey card the same as taking an incident reading? and wouldn't the given readings be exactly the same in each case? (spot reading grey card or incident meter reading)</p>

<p>What I dont understand is why I would need to know how much difference there is between a grey card and a bright light wall for example. Cant I spot meter it and get a Zone v reading and then close down 2 stops to get a zone lll exposure reading?</p>

<p>Sorry to go on but I would like to get my head round something that I have been doing for years but apparently wrongly.</p>

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<p>Yea, I do agree that this spot metering of a gray card makes no sense and, again, is a misunderstanding of what a spot meter does.</p>

<p>RE:Acros and the zone system. I don't think that the physics of light change. If Acros sees the spectrum like other film, then it should work like other film. If it is more of an orthochromatic or blue sensitive film then we have a different situation. The idea of the zone system was to determine the proper iso rating and development of any given film, full spectrum, so that the steps/stops of light fell within certain density parameters for each zone. Those densities were what was necessary at the time to properly print with standard printing papers. The only reason that a film wouldn't respond predictably would be a really short straight slope and pretty severe toe and shoulder characteristics--or it isn't full spectrum.</p>

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<p>My Zone III placements for bright subjects yield a different negative density than my Zone III placements for dim subjects. The reason is that my spotmeter, an old Pentax with an analog scale, reads in a <em>non-linear</em> way. Double (or half) the light does not result in double (or half) the meter reading!</p>

<p>Of course I have measured the non-linearity and stuck a correction scale to the side of the meter. For example if my meter reads 8 on the scale I know the correct reading is 8 2/3 and expose accordingly.</p>

<p>Another stray cause of non-linearity is spotmeter lens flare. A mid grey patch won't read the same if surrounded by bright stuff compared to the same patch in the same light when surrounded by black stuff. A good meter will have less flare but in contrasty light it may be necessary to walk up to the subject and do close-up readings. That's the chore an expensive spotmeter is supposed to save you from but sometimes you have to walk!</p>

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