Exposure in the woods

[John Irvine]

In the woods around our house, there are a number of different fungi that I think are interesting enough to make a decent picture. I have been unable to figure out how to get a good exposue under the trees. The conditions are a bright sunny day. The woods are deep enough that there are no shadows except in the dappled spots of sun. The subjects are fan shaped fungus on decaying limbs or stumps. They are primarily shades of gray, in rings. The outer ring is white. The backgrounds are old wood in shades of brown and gray and/or brown leaves. In the latest failure, the spot meter readings range from 6.8 in a dark brown part of the tree to 9.4 for the lightest part of the fungus. That is getting as much of the outer ring as possible in the spot. In the same light, the palm of my hand was 9.2. I waited until there were no spots of sun in the area I was photographing. By experience I have found they are too bright to balance with rest of the picture.

Having tried a lot of different things in this situation, I set 9.2 for Zone VI and set the exposure. The film was TX 320 shot at 160. Development was N+1 in HC 110. The result was a generally muddled negative. I had visualized the outer white ring as white, with some detail (VII?) with the gray rings having sharp differences in shade. The background had about the detail I was looking far but is not as dark vs the subject as I would like.

I am at wits end, trying to get good exposures of things on the ground under the trees.

 

[Anscojohn]

You don't really say what "muddled" means.My suggestion is to ignore the white rings; expose and develop for density and separation in the lower tones and let the whites fall where they will.

In ye olden dayz and dayz of yore, one always hoped for clouds which moved quickly in and out of the sunlight. Made one exposure in the "dark." Recocked the shutter and waited for the sunlight to come out again. Or was it the other way around?

Btw, what color is the fungus? If green, perhaps a bit of green filtration will help??

 

[Nicholas Lindan]

TX 320 shot at 160. Development was N+1

So you overexposed and overdeveloped - muddled is what you should get.

You have a 2.6 stop subject brightness range, which isn't much.

The Zone system is nothing more than elaboration of the old expose for shadows, develop for highlights. Always start your figuring from the shadows and work to the highlights.

If it were me, I would set the meter to 320, meter the brown wood, close down 2 1/2 stops and develop about 30-40% more. I would also bracket a stop either side. That should place the wood at about III 1/2 and the light part of the fungus at VII 1/2.

 

[mcd]

Meter for the tree, place at zone 3.5, plus 1 development.

In the woods around our house, there are a number of different fungi that I think are interesting enough to make a decent picture. I have been unable to figure out how to get a good exposue under the trees. The conditions are a bright sunny day. The woods are deep enough that there are no shadows except in the dappled spots of sun. The subjects are fan shaped fungus on decaying limbs or stumps. They are primarily shades of gray, in rings. The outer ring is white. The backgrounds are old wood in shades of brown and gray and/or brown leaves. In the latest failure, the spot meter readings range from 6.8 in a dark brown part of the tree to 9.4 for the lightest part of the fungus. That is getting as much of the outer ring as possible in the spot. In the same light, the palm of my hand was 9.2. I waited until there were no spots of sun in the area I was photographing. By experience I have found they are too bright to balance with rest of the picture.

Having tried a lot of different things in this situation, I set 9.2 for Zone VI and set the exposure. The film was TX 320 shot at 160. Development was N+1 in HC 110. The result was a generally muddled negative. I had visualized the outer white ring as white, with some detail (VII?) with the gray rings having sharp differences in shade. The background had about the detail I was looking far but is not as dark vs the subject as I would like.

I am at wits end, trying to get good exposures of things on the ground under the trees.

 

[Chuck_P]

You waited for "no spots of sun" to make the exposure. Which means to me that you exposed in diffuse lighting or full shade; therefore expansion of the density range of the negative is usually called for. You essentially provided for increased exposure by "placing" it high on the scale and then developed to N+1. If I understand you correctly, you did not really expand the density range of the negative with N+1 dev. You need to reduce the given exposure by "placing" the shadow area low on the scale that suits your visualization, then determine where the highlight on the fungus "falls". If it falls on VI and you want VIII, then try N+2, if it falls on VII and you want VIII, then N+1. If it falls on VII, and your ok with that, then "N" dev. Just remember that if you're going to provide "plus" development, then you are indicating an expansion of the negative density range to yield greater negative contrast from a scene of generally low contrast.

 

[keithwms]

Shoot it to slide and be happy

 

[benjiboy]

I think you are overcomplicating the matter, I would meter the shadows, shoot the film at its box speed, and develop it in D76, or some normal type developer.

 

[John Irvine]

It all sounds so simple here at the computer. When I get in the field, all sorts of thoughts come crashing in to confuse me. I am easily confused. I know to "expose for the shadows and develope for the highlights" but there at the camera, I am liable to do anything. The weather should stay favorable this week so I can get back and try to do it right. I will expose for the darkest part of the wood and give it about III.5 exposure. Then I'll develope N+1 if the lightest part meters for VI and N+2 if it meters for V. I'll also watch the sun to make sure there are no sunny spots are in the picture.

 

[MurrayMinchin]

You're using the zone system and a spot meter...are you using large format? If you are (and if you're taking a close up of fungi) did you apply a bellows extension factor to your exposure?

I've found in subdued forest light that after applying reciprocity failure compensation (without reducing development) and/or applying a bellows extension factor while basing the exposure on shadow detail, that it's like giving + development...because while the shadows are slowly filling in, the higher mid tones are really chugging along and piling up the photons.

Murray

 

[John Irvine]

I was using 4X5 with a 215 mm lens. I have seen the term "bellows extension" but have not studied it much thinking it was not necessary with what I was doing. The subject was 3 to 4 feet from the film. The lens was less than 10 inches from the film. The area of the fungus was about 8X8 took and up about 2/3 of the film area. It was not an extreme close up which is where I thought bellows extension becomes a factor.

 

[Nicholas Lindan]

reciprocity failure compensation (without reducing development)...because while the shadows are slowly filling in, the higher mid tones are really chugging along and piling up the photons.

That might be a technique to increase contrast... Add lots of ND filters and use a small f-stop for intentional reciprocity failure. Anybody tried it, and not just by accident?

 

[MurrayMinchin]

I was using 4X5 with a 215 mm lens. I have seen the term "bellows extension" but have not studied it much thinking it was not necessary with what I was doing. The subject was 3 to 4 feet from the film. The lens was less than 10 inches from the film. The area of the fungus was about 8X8 took and up about 2/3 of the film area. It was not an extreme close up which is where I thought bellows extension becomes a factor.

That's probably the culprit. This is from the top of my head, but somebody will probably chime in with the actual bellows extension factor. A 215mm lens is about an 8.5" lens, which means its nodal point is 8.5" away from the film when focused at infinity. To focus on closer objects the lens moves further away from the film, and at some point (remember the inverse square law?) you have to increase exposure to compensate for the decreased light hitting the film.

I have to take off for work, so hopefully someone can give you the actual formula...

Murray

 

[keithwms]

For bellows factor I use this:

exposure correction factor for bellows extension= (1+m)^2

where m is the mag. factor. So for example, if you shoot a subject at 1:1, then m=1, and the additional exposure factor is (1+1)^2=4, so you have to quadruple your exposure. If your subject is twice as big on the film / ground glass as it is in reality, then m=2, and your exposure correction factor rises to 3^2=9, and you multiply your exposure time by 9....

So... since this factor is proportional to m^2, obviously it is extremely important for close focusing. People use tape measures and whatnot to get the value of m as precisely as possible; I do this especially when shooting slide macros.

 

[eddym]

I was using 4X5 with a 215 mm lens. I have seen the term "bellows extension" but have not studied it much thinking it was not necessary with what I was doing. The subject was 3 to 4 feet from the film. The lens was less than 10 inches from the film. The area of the fungus was about 8X8 took and up about 2/3 of the film area. It was not an extreme close up which is where I thought bellows extension becomes a factor.

I calculate about a half stop exposure loss at that extension.

 

[Chuck_P]

I simply pre-calculated my bellows extension factors (BEF) using the millimeter scale on my monorail using: [bellows ext^2 / focal length^2] = BEF.

Ex: my 210mm lens needs to be 8.25" from the film plane to mark infinity, once that is found, I measured the distance inside to inside of each standard-------it happens to be 126mm. So I can find inifinity quickly by making sure my standards are 126mm apart inside to inside. I simply advanced the front standard in 1/2 inch increments and recalculated the factors for about 6 inches worth of extension. If my standards after focusing are 177mm apart, then I know the lens has been moved forward 2 full inches and my little chart reads: 177mm = 10.25" ext = 1.5x factor.

Very quick.

 

[Lee L]

That might be a technique to increase contrast... Add lots of ND filters and use a small f-stop for intentional reciprocity failure. Anybody tried it, and not just by accident?

This is done routinely in astrophotography to test reciprocity failure rates. A 10 stop ND filter is used, and exposure goes from 1/8 sec (0.125 sec) without the filter to 125 seconds with the filter. Bracket the long exposure with f-stops, check the number of extra stops needed to match the non-filter exposure, and you have something to plug into the Schwarzschild or modified Schwarzschild formula.

Howard Bond tested five films for reciprocity failure a few years back (Photo Techniques Jul-Aug 2003), and found that most of the modern films he tested didn't have the increase in contrast that's been traditionally expected to accompany reciprocity failure.

In the past, films typically yielded
increased density ranges with long expo-
sures. The extra exposure that rendered
Zone III as planned was less needed in the
high zones, so they were elevated, increas-
ing the density ranges.This situation is now
much improved. At 240 seconds indicated,
T-Max 400 and 100 Delta showed no eleva-
tion of Zone VIII. Tri-X was up slightly, but
only slightly more than the typical varia-
tion from one trial to another. The Zone
VIII densities from HP-5+ and T-Max 100
were elevated about 2/3 zone.

Lee

 

[Michael Kadillak]

Forget about making field math calculations or getting a tape measure out for close up images.

Get one of the inexpensive Calumet bellows extension tool. Put the wafer in your photograph and measure it (the wafer) on your ground glass to arrive at the proper extension. Dial in the proper compensation, take the wafer out of your photograph and make your image. There is no easier way to arrive at this correction. Spend your time "looking at the quality of the light" within your photograph.

To much extraneous activity while in the process of making photograraphs can quickly become counterproductive to the end objective.

Case in point - I read that Brett Weston did not even use a light meter. He trained himself to "see" the intensity of the light when he photographed.

 

[Anupam Basu]

To much extraneous activity while in the process of making photograraphs can quickly become counterproductive to the end objective.

Of course this varies from person to person. For example, the wafer method constitutes too much extraneous activity for me. I find the math much easier and simpler and I get the extension simply by looking at the bed of my camera.

 

[Thomas Bertilsson]

Nicholas, I do this all the time, but with very small apertures and pinhole cameras. On a bright and sunny day, at f/138 and ISO 100 film, I hoover around 1 second. In any other condition, with the Plus-X film I use, the reciprocity between time and exposure starts to taper off severely, to the point that I can get lighting effects I want with long exposures in any other light than broad daylight.
If I was shooting Fuji Acros, which is stable down to two minutes, I would not be able to manage the shots I do with pinhole, unless I figured out a way of doing filters on it, and then I'm getting away from the raw and simple approach of photographing even without a lens...

It works great for me.

- Thomas

That might be a technique to increase contrast... Add lots of ND filters and use a small f-stop for intentional reciprocity failure. Anybody tried it, and not just by accident?

 

[Michael Kadillak]

Of course this varies from person to person. For example, the wafer method constitutes too much extraneous activity for me. I find the math much easier and simpler and I get the extension simply by looking at the bed of my camera.

By looking at the bed of your camera it sounds like you have already completed the computations and developed a template for this purpose.

If you only use one focal length lens I guess this would work.

I use lenses that have focal lengths that range from 6" to 42". The wafer/scale system is completely indifferent to a lens focal length and can be executed in seconds. Using a tape measure I was never quite sure as taking a measurement from the lens board or the node of the lens which can be different.

 

[Anupam Basu]

By looking at the bed of your camera it sounds like you have already completed the computations and developed a template for this purpose.

If you only use one focal length lens I guess this would work.

Nope. The bed of my camera merely gives me the extension and saves me the trouble of using a tape. I divide this extension by the focal length and square the result. Seems quite quick enough to me and hassle free. No more mental strain than thinking about zones and brightness ranges, really. But so many photographers seem to be mortally afraid of squaring things

 

[Shelly Grimson]

Well I think Fred Picker had the answer. He said to use the same approach as architectural photographers use to get a window lit evening pic where the outside is darkened and the interior remains lit by its own lighting. To get both areas exposed and to save both areas of tone do two exposures. First expose for the shadow area that you want. I usually drop one and a half stops. Then double expose and do a second exposure (don't move the camera) to get the highlight areas of foliage or rock at about zone 6 or 7 depending on how much detail you want. As long as there is no wind you will get perfect exposure. You see, the highlit area is such a small fraction of the longer lower lit area in time that added on it doesn't really affect the shadow exposure significantly. I've gotten some situations covered this way that could never been saved by all the contraction and expansion of the Zone system. Why- because you are using the film at box speed (or your own derived best rating) and you don't have to lose anything in the expansion or contraction process. Mainly, in roll film you are always going to be nervous that you chose the wrong this or that! Try it and see.

shelly
Ps. I'm in Toronto where the light variation can be quite great on a sunlit day but I'm sure that out West the spread is greater between shadow detail areas and sunlit highlit ones. I hope this works for your situation....

 

[Anupam Basu]

First expose for the shadow area that you want. I usually drop one and a half stops. Then double expose and do a second exposure (don't move the camera) to get the highlight areas of foliage or rock at about zone 6 or 7 depending on how much detail you want. As long as there is no wind you will get perfect exposure. You see, the highlit area is such a small fraction of the longer lower lit area in time that added on it doesn't really affect the shadow exposure significantly.

I'm sorry, but I don't understand this. Could you explain. It seems like you are suggesting two exposures - one for the shadows and one for the highlights. But how do you manage to not blow the highlights when exposing for the shadows?

-A

 

[mcd]

Huh?

I have no idea how his can possibly work, unless the light has changed between exposures.

Well I think Fred Picker had the answer. He said to use the same approach as architectural photographers use to get a window lit evening pic where the outside is darkened and the interior remains lit by its own lighting. To get both areas exposed and to save both areas of tone do two exposures. First expose for the shadow area that you want. I usually drop one and a half stops. Then double expose and do a second exposure (don't move the camera) to get the highlight areas of foliage or rock at about zone 6 or 7 depending on how much detail you want. As long as there is no wind you will get perfect exposure. You see, the highlit area is such a small fraction of the longer lower lit area in time that added on it doesn't really affect the shadow exposure significantly. I've gotten some situations covered this way that could never been saved by all the contraction and expansion of the Zone system. Why- because you are using the film at box speed (or your own derived best rating) and you don't have to lose anything in the expansion or contraction process. Mainly, in roll film you are always going to be nervous that you chose the wrong this or that! Try it and see.

shelly
Ps. I'm in Toronto where the light variation can be quite great on a sunlit day but I'm sure that out West the spread is greater between shadow detail areas and sunlit highlit ones. I hope this works for your situation....

 

[Shelly Grimson]

Yes it is two exposures of the same subject (double exposure). I usually shoot one with the camera set for proper rendering of shadows, and then cock the shutter and take an exposure with the shutter speed altered to render the proper reading for a highlight area-around zone 6 (one stop over meter reading of the bright leaves for example. The two exposures on the single frame will produce the desired image.