Bellows extension requirements for close up ‘Blurred tip of nose’ wide open portrait

Hi all,

I’m new to large format camera and trying to figure out the focal length and bellows extension requirements for close up full head and shoulders with ‘Blurred tip of nose and ears’ wide open portrait shot. For the Rodenstock 210mm f5.6 Sironar-N lens, would 350mm bellows extension enough for shots like that? Would 250mm bellows extension too short for that?

I’m thinking of getting a Chamonix hs-1 (bellows 50~250mm) or h1 (bellows 60~350mm) and a suitable portrait lens.

Many thanks in advance.

I would think (almost) any lens will give you that affect. A 210mm lens on a camera with 350mm bellows extension should do it. 250mm of bellows may not be enough to get the dramatic shallow depth of focus you desire, with a 210mm lens, but with a 150mm lens it should be enough.

Hmm. Something doesn't compute here. With a 210 mm lens, 350 mm of extension gives magnification of ~ 0.75. At that magnification an adult's head and shoulders won't fit on 4x5 film.

With a 210mm lens at typical portrait distance and open to f/5.6 , the depth of field will be rather shallow: you can search the web for depth of field calculators to see the exact number. The trick is to come in close and open the lens wide. Hold your subject steady or even the slightest movement will spoil the effect.

Required bellows extension depends on focal length, subject distance and desired magnification. You may find this page helpful: http://www.kennethleegallery.com/html/tech/bellows.php

I use a 210mm for portraits and 250mm won't be quite enough. You can shoot portraits, but I have always found it distracting to shoot when you are at the end of your bellows extension. It always feels like you are having to limit your creative choices because of the shortcomings of your equipment.

Quote:

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Originally Posted by Ken Lee

With a 210mm lens at typical portrait distance and open to f/5.6 , the depth of field will be rather shallow: you can search the web for depth of field calculators to see the exact number. The trick is to come in close and open the lens wide. Hold your subject steady or even the slightest movement will spoil the effect.

Required bellows extension depends on focal length, subject distance and desired magnification. You may find this page helpful: http://www.kennethleegallery.com/html/tech/bellows.php

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I don't know if the OP found it helpful, but I sure did, thanks!

To the OP's question, first, what's "head and shoulders" for you and your intended subject? About 1/5 life size? I.e.: for a 4x5" piece of film (actual image size is about 96x120mm), a 1/5 life size works out to be 5x the size of the piece of film, or just a bit under 20x25" (480x600mm). That seems to be a good guess for a somewhat tight head and shoulders shot. From Ken's "How much bellows do we need" for 1:5, that's 210/5 + 210 or 252mm, so the 250mm extension camera is just a bit short. A 1:5.5 or 1:6 "head and shoulders" shot would just work, though.

The 350mm extension gives you lots more options, especially should you find later that you prefer a 240/250mm portrait lens (I use a 250/4.7 Fujinar or a 250 Imagon for many portraits, and have 365mm of extension on my camera).

Thank you all. I really appreciate all your input. I may go with the H1 and get the Rodenstock 135mm Sironar-N lens for landscape and Rodenstock 210mm Sironar-N lens for portrait...or Hs-1 with just one Rodenstock 150mm Sironar-S lens for both landscape and portrait. The bellows calculation is a bit confusing but I will figure it out. Happy shooting!

Part of the reason it may be confusing is there is no standard definition of "blurred", the amount of blur that is wanted has to be judged by eye using the lens and subject, estimates made in advance can't eliminate the uncertainty of how much blur is enough? It may be necessary to go 8x10 if the blur that you want can't be found with 4x5.

8x10 Kodak 2D, 90mm Nikkor f/8 at ,12 inches from nose. Extension and correctioln . . .a LOT!

Blurry enough?