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  1. #21

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    Takes all the thought out. Jbrunner's site has one like it too. Screw the math. There are also tables available on the net to print. SOme folks just like math. Not me.

    http://www.southbristolviews.com/pic...ic/SBVCALC.pdf
    Technological society has succeeded in multiplying the opportunities for pleasure, but it has great difficulty in generating joy. Pope Paul VI

    So, I think the "greats" were true to their visions, once their visions no longer sucked. Ralph Barker 12/2004

  2. #22
    markbarendt's Avatar
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    Definitely relax and have fun.

    Be sure to try a portrait where the head nearly fills the frame. First time I tried this my brain flipped the image upright, way cool!

    Try this link for bellows factor compensation;

    http://www.salzgeber.at/disc/disc.pdf
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  3. #23

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    It's not that difficult, folks! It's easy to figure bellows factor to within 1/3 stop. We'll take an 8x10" camera with a 12" lens.

    Let's assume that calculating within 1/3 stop is as accurate as your exposure is likely to be or need be in any case.

    At infinity, the distance between the film plane and the aperture diaphragm is 12".

    If you're focusing at a relatively close distance (say 6 feet), you extend the bellows beyond 12". Measure the distance between the film plane and the aperture diaphragm. Let's say it's 16".

    The inverse square law tells us that a bellows extension of 24" (twice the focal length of the lens) will require two stops of exposure compensation (intensity of the light is quartered). 18" of bellows extension (1.5 x focal length) will require 1 stop of extension compensation (intensity of light is halved). Our 16" of bellows extension is about 2/3 of the distance between 12" and 18". We need 2/3 of a stop bellows compensation. 14" would give us 1/3 stop compensation. You can make a chart very quickly this way if you need.

    14" = +1/3 stop
    16" = +2/3 stop
    18" = +1 stop
    20" = +1 1/3 stops
    22" = +1 2/3 stops
    24" = +2 stops
    28" = +2 1/3 stops
    32" = +2 2/3 stops
    36" = +3 stops* (* the math whizzes in the group will say that this is not entirely accurate, since the inverse of three times the focal length squared is 1/9th the light transmission and not 1/8th. Open up a smidgeon more.) I figure your camera probably doesn't have more than 30" of extension, so you're probably safe using this chart. If you're doing extreme closeups, use the measuring system in the download provided above. It's more accurate.

    The math is not that tough. I never got better than a "B" in math after I was introduced to algebra.

    Peter Gomena

  4. #24
    markbarendt's Avatar
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    It's even easier with the things Mark and I suggested.
    Mark Barendt, Ignacio, CO

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  5. #25
    Michel Hardy-Vallée's Avatar
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    OK, here's how I'm going to stop worrying and learn to love the bomb: this PDF is a simple chart I calculated in Excel for a 300mm, based on the formula Ian C passed.

    There are two important thing to remember: at 300mm we have infinity focusing, so no bellows factor. At 600mm we are at 1:1 reproduction ratio, which needs 2 stops compensation. Beyond that, it's all tight macro work.

    Which means that for any non-macro work with a 300mm, I should expect at most a 2 stops correction. Negatives being negatives, minute errors will not be dramatic. Still, what I did in my chart is to put in bold every 1/3 of a stop increases.

    So, armed with a measuring tape (or the camera's, since it's a monorail), I do a quick check of bellows length, match with my chart, and I can adjust exposure within 1/3 of a stop.

    The next time, with a different lens, I just have to recompute my table.
    Attached Files
    Using film since before it was hip.


    "One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11

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  6. #26

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    Bring some snacks. When I try my first 8X10, I had my breakfast and go out. After carrying camera and film case about 25 lb, three lenses in a bag about 15 lb, tripod with gear head and a two screws stable bar under the camera over 10 lb. After two shoots and some move around I feel very hungery. I have jump back to my car and go for lunch.

  7. #27

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    Think of your outing with an 8x10 as like being on a date with Famke.

  8. #28

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    And now you have no worries.

    Enjoy your 8x10. It is an experience like no other.

    And plan your field shoots to be close to your car.

    Peter Gomena

  9. #29
    Michel Hardy-Vallée's Avatar
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    Hmm... 8x10 snacks.....
    Using film since before it was hip.


    "One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11

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  10. #30
    Michel Hardy-Vallée's Avatar
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    Alright, back from the long Easter weekend with 25 shots, and not even a single screwup! I guess knowing how to meter and develop films really pays off!

    The resolution from the prints is just INSANE. When you look at the 8x10 from a normal viewing distance, you think "hm, sharp" but when you put your nose to it, you suddenly fall into the print. What's more, the gradations are perfect, and the tonality is puddingly rich. It pushed me to order a pack of Lodima paper to try contact printing on AgCl.

    The 300mm lens turned out to be mildly telephoto, so that even at close range there was no bellows factor to worry about. HP5+ was exposed at EI 250 (spot readings), and given a good 15 minutes in HC-110h. Negatives all print beautifully on ILFORD MGIV RC at grade 2, sometimes 1.5. We did landscape (orange Lee filter, behind the lens because the front element of the 300mm Symmar-S is so damn big!), portrait (red filter for the ladies, none for the lads), and still life (a powerfully ugly lamp that caused many focus challenges).

    Working with a monorail in the field is rather challenging, since you can't easily put the camera on the ground in a safe position, but by working in a team of two, the travails were supportable.

    What's more, I have to repeat the inevitable truism: large format slows you down, and makes you think harder about your pictures. The efforts required prevent you from taking pictures that you find only mildly interesting. You focus more, and are more critical: if a scene does not reach a particular personal threshold of quality, you just forget about it. My Rolleiflex never felt so small, nor so lithe.

    I'm also quite pleased by my relative success with intuitive Scheimpflug. Most photos were shot around f/32, but using a bit of tilt did help, and shift also proved quite helpful in adjusting composition.

    The bug bit me; remains to see how I will let it eat me over time. I think I would love a (relatively) light 8x10 field camera, a normal-ish lens, and a few holders to do contact prints...

    Oh, and I think I will ask Elevator to print me a 16x20 from a neg, too...
    Using film since before it was hip.


    "One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11

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