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blevblev
5-Mar-2008, 13:44
I'm trying to determine if metering the sky is just like metering an object on the ground. When I'm metering for high and low values, should I only use things that reflect light, and ignore the sky? The sky seems more like a light source (particularly a bright overcast) and I am confused about what zone to place it on. It seems like whenever I take the sky into consideration, the high and low values go off the scale requiring minus processing. The mid values still end up being too low and I have to reduce print exposure and burn in the sky. Is this just the way things are, or will it have a positive effect to just meter things on the ground.

I hope I'm explaining this correctly.

Vaughn
5-Mar-2008, 13:58
Well, with the Zone System, you are not placing your high values anywhere. You "place" your darkest area you want detail in on about Zone III and see where the highlights (and sky) "fall"...and then develop to get those highlights to fall where you can use them.

Not much one can do with a bright over-cast...one generally has the choice of a white sky, or burning the sky in the print. On a sunny day, one can use yellow, orange or red filters to lower the value of the blue sky relative to the other values in the scene.

I had some scenes recently in Yosemite where the snow was a stop to two stops brighter than the blue sky. In theory, when I print the snow as a Zone 8 to 9, the sky should be a nice Zone 7 (I don't generally like dark skies, but I could have brought those skies down a zone or two by using a filter.).

I solve much of my problems with skies by rarely including them in the image!

Vaughn

gregstidham
5-Mar-2008, 14:17
I would agree with Mr. Vaughn. If the sky is a problem, don't include the sky in the composition. Or, try playing with various grades of graduated ND filters. A .3 or .6 will knock a sky down.

srbphoto
5-Mar-2008, 14:43
I meter the sky with my spot, just like everything else. I decide if I can comfortably burn the sky. If so I will let it go, knowing I will have to knock it down in the darkroom. If not, out comes the Graduated ND filters. If the sky (or open area) is in the image where a Grad ND filter will not work I will flash the area. If the sight of me in the darkroom with my pants down doesn't knock those bright skies down, nothing will!:eek:
Just remember if you are going to burn a bright overcast sky that it will go from a nice light gray to a muddy mess very easily. Watch those test strips!!!

lenser
5-Mar-2008, 15:28
Many black and white films seem to be hyper sensitive to blue light and therefore overexpose the sky relative to the foreground out of proportion to what you might expect. Use of the colored filters already mentioned definitely help, but add a polarizer to the mix. This will remove the glare factor and give a denser sky either in black and white or color. Combined with a red filter and at just the right angle to the sun you get a near black sky. With yellow, it's a deeper gray.

The graduated ND filters are wonderful, but can be a pain if you have anything but a flat horizon.

Follow what others have said about metering the dark areas for your exposure base, allow 2 stops for the polarizer, plus 1 stop for yellow, or three for deep red. Adjust your exposure and go from there.

Hopefully that will get you where you want to be.

Tim

CG
5-Mar-2008, 16:04
Your explanation is very readable. And the issue you mention is real.

Yes, meter the sky, if you care about placing it's value intentionally. Sometimes you will need reduced development to hold the entire scale of values. A really cloudy bright sky can be tough to work with.

Sometimes burning and dodging works best.

Other times a blown out sky makes sense.

Best,

C

Nathan Potter
5-Mar-2008, 16:30
If you want to resolve detail and texture in a scene that meters more than about 8 zones you can't using just N- development techniques. In such cases for B&W films I do 2 exposures - one for the sky or bright regions and one for the darker regions. Must be absolutely identical images without moving the camera or subject. These two negs can be combined in the darkroom by various techniques (sometimes making separation negatives using lith film for example, (huge PITA). But here is where Photoshop can shine using layers etc. and combining images. Since I'm still new at PS I'm sure others here can suggest a possible workflow.

Nate Potter

blevblev
5-Mar-2008, 17:44
Re: you are not placing your high values anywhere

Right, I realize that you place the low values, so I didn't mean to say that I was placing the high values when I expose the film, but you sort of do by metering the high values and then deciding what to do in development. I should have been clearer.

Anyway, it looks like I'm not alone. I had forgotten about graduated ND filters. I'm still putting my LF kit together and I haven't gotten to filters yet except for the gelatin filter holder and 5 or so gelatin filters that came with my camera when I bought it on ebay. In the mean time, I'll try the various techniques suggested here.

domenico Foschi
5-Mar-2008, 19:01
SOmething that hasn't been mentioned is paper flashing.
In many cases it has helped me to save an image from the box of the rejects.
Many times just burning the sky will result in an obvious burn edge, by combining burn and paper flashing you can achieve great results.
Only paper flashing might get the sky away from the dreaded zone X but rarely you will get texture.

domenico Foschi
5-Mar-2008, 19:05
I apologize, somebody did mention paper flashing....:o

srbphoto
5-Mar-2008, 19:13
I have had great luck with flashing and have been able to pull detail out areas that would have been impossible to burn. Of course, the info has to be in the negative.

When I use this technique I leave the neg in and open the aperature wide open. I will use a #5 filter (when using multigrade). If using graded paper I will (usually) go up 1 grade. Then I create a test strip to get the exposure right. I will do selective burning this way as well.

Capocheny
5-Mar-2008, 22:23
If I remember correctly from Per Volquartz's workshop... you can also pre-flash the film in your holders.

I can't recall the exact technique but, perhaps, someone who has attended one of Per's workshops will be kind enough to post the information here.

Cheers