loss of shadow detail - Xtol

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I'm attempting use of the simplified zone system. http://www.simplifiedzonesystem.com. I spot meter on the white part of my reference tone, then open up 2 stops. Pull my film 2 stops. Whites are white with detail, blacks are black. The photo's definitely have "punch" but midtone shadows are going too dark (unrealistic). Frankly I'm ready to give up on Xtol and go back to ID11. The reason I'm trying Xtol is it claims excellent shadow detail. Any idea's?

Here's my combo. Delta 400 Xtol 1:1 9 min Agitate at 1 min intervals. LDP 1:8 Ilford IV FB

-- Joseph Lacy (jmlacy@flash.net), May 25, 2000


Joseph, you should spot meter the shadow area(darkest part of the picture you want to show texture ot detail)and open up two stops. I usually open up one more stop if I shorten development for high values. You really need to calibrate your system to determine your correct film speed.

-- Don Sparks (Harleyman7@aol.com), May 25, 2000.

Oops, meter the shadow area and close two stops for a zone 3.

-- Don Sparks (Harleyman7@aol.com), May 25, 2000.

Don is right. Keying your exposure off of Zone 7 will almost guarantee that you will lose shadow detail if you have a scene with a long scale. Typically, you should meter the shadow area you want some detail in and place it on zone 3 (i.e., give two stops less exposure than the meter indicates for that area), then develop until your high values are where you want them to be. To make sure your highlight values will fall where you want them, you should also measure the highlight value you want some detail in (Zone 7). If this falls outside the area you can capture with the exposure you have determined (for the shadows), then you will either have to pull or push when you develop. Calibration is necessary to determine what the true exposure index is for your film/camera/lens/development technique combination.

-- Ed Buffaloe (edbuffaloe@unblinkingeye.com), May 25, 2000.

But where will that place the whites? Seems to me white then becomes Zone 5 or 18% grey.

-- Joseph Lacy (jmlacy@flash.net), May 25, 2000.

Let's first get the conventions clarified:

Zones I to III are the shadows, with zone III giving full shadow detail, zones II and I giving no detail any more.

Mid grey (18%) should be zone V.

Depending on the amount of detail desired, the highlights should be somewhere in zone VII (full detail), VIII (no detail, but not yet paper base white) or IX (usually paper base white).

Meters are calibrated to zone V.

So, when you meter the fully detailed highlights, zone VII, and close two stops, this will get you to zone V, which seems fine so far.

Metering the fully detailed shadows, zone III, and closing two stops will get you there, too.

The third way to get there is measuring the gray card and taking that value as-is.

Now for the catch: If the scene is rather contrasty, the range between what you want to be fully detailed highlights and what you want to be fully detailed shadows may be more than four f-stops. When you come from the highlight end of the scale, this will let the shadows slip into zone II, which means they drown in black, no detail any more. The highlights are zone VII, which is fine.

Otoh, when you come from the shadow end, metering for zone III, and finding that the highlights would have no detail any more, you can modify your development to pull the highlight density down as required w/o losing shadow detail. With some film/developer combinations which do not have a shoulder in the characteristic curve, you might also develop the film as usual and try to get detail into the highlights by burning them at the printing stage.


-- Thomas Wollstein (thomas_wollstein@web.de), May 26, 2000.

nice explanation Thomas.

"So, when you meter the fully detailed highlights, zone VII, and close two stops, this will get you to zone V"

should read as open two stops.

simplify the Zone System as much as possible, so that it works for you. sounds like you are almost there Joseph. good luck!

-- daniel taylor (aviator@agalis.net), May 27, 2000.

Actually metering for the highlight is not a bad way to go for most outdoor shots. I kept a log once of scenes I had metered and with bright puffy clouds and "normal" subjects a 4 stop spread is normal and 5 stops quite rare. So placing your highlights on Zone 8 in these situations you will still get plenty of shadow detail. As an experiment, go outside on a sunny day with a white and black card, put the white card in the sun and the black card in the shade and spotmeter them, you'll be suprised by the results.

Of course backlit scenes, which I shoot a lot of, can have SBR's of quite a bit more than 5 stops in which case placing your highlight on zone 8 will not work.


-- Mark Bau (markbau@altavista.com), May 29, 2000.

I would be very careful taking a meter reading off of any Z8+ scenes and thinking most scenes will be 4 stops or less so it would be ok to develope normally. You can't move the low values with development as readily as high values because low values don't have much exposed silver halides to develope as opposed to high values. Therefore the highlights become denser faster and more completely than the shadows and most papers can't hold that much density subject brightness range. High values have lots of exposed silver so the high values become dense much faster than low values. Simple physics. I have never had an explanation of Freds zone system that satisfies my understanding of how exposure and development works. I see the work of some of Fred's practitioners but they all seem to have very dark shadows with little detail in areas (thin shadow areas in neg) that should be full of detail. I followed Fred's methods in his first edition but was not satisfied with the results. I feel if it was a valid method many more people would use it. The old saying "expose for the shadows and develope for the highlights" is a pretty foolproof method to go by. James

-- james (james_mickelson@hotmail.com), May 29, 2000.

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