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Gerry Harrison
3-Sep-2006, 09:13
Hello Gents ( and I'm sure a few Ladies ),

I'm very new to LF...so new I have not taken a shot at this point..still accumulating all the gear required to launch..80 % there. The mind starts to work while the waiting takes place so here is one question I need resolved in regards to the close up capabilties of a LF lens.I have a Schneider Symmar-s 210/5.6..the bellows I'm sure would make closeups possible..but what can I expect from this lens in this area. I have a Cambo SC-2/NX 4x5.

Thanks again Gerry

Ron Marshall
3-Sep-2006, 10:30
You will need 420 mm of bellows for 1:1. It won't be quite as sharp as a macro lens that is optimised for 1:1, but you won't see a difference if only making small enlargements.

Are you planning a shoot at Butchart Gardens?

Donald Qualls
3-Sep-2006, 14:21
For whatever it's worth, it's actually *easier* to shoot macro with a shorter lens, because you don't need as much bellows. I can easily do 1:1 with my Speed Graphic using a 135 mm lens, and I originally mounted my 105 mm Agnar with the thought of shooting some 2:1 images. Also worth noting, most process and enlarging lenses, sometimes reviled for camera use because they aren't optimized for infinity focus, will be significantly better in the range from 1:10 to 1:1 (even as close as 10:1 in some process lenses) than a landscape-optimized photographic lens. For instance, a Componon might well outperform your Symmar-S for distances of a few feet or less...

Very important if you get closer than about 1:2 (image half life size) that you remember to include "bellows factor" in your exposure calculation -- add one stop at 1:2, two stops at 1:1, and 4 stops at 2:1. If you're using transparency film, you'd be ahead to recaculate the effective aperture based on the actual bellows draw relative to the infinity focus position -- multiply nominal focal length by aperture on the scale to get effective aperture diameter, then divide actual focal length (determined by adding the bellows draw needed to focus) by that effective aperture to get the new relative aperture.

Any 4-function solar calculator (weighing 1/4 ounce) can handle the necessary math, but there are also methods of doing this by using an object of known size temporarily in the field at a known distance, and measuring its image on the ground glass before looking up the correction in a table specific to your focal length.

Colin Robertson
3-Sep-2006, 14:27
Okay- as you rack out the bellows the image gets dimmer and dimmer. SO- search this site for the 'quickdisc'. Its a free download you print out. Part one is a disc you include in the shot, and part two is a 'ruler' with which you measure the size of the disc on the ground glass. It gives an instant exposure factor correction. Genius. Just remember to take the disc out of the shot before exposure. . . .

Ernest Purdum
4-Sep-2006, 15:54
Since you already have the lens, try it. I think you will be pleased with the lens performance whether it is the theoretical optimum lens for the purpose or not. There are so many other factors that affect the image quality in close-up work that I wouldn't consider anything else before giving what you have a good try. If it were an obvious inappropriate choice like a radically asymmetrical speed lens, that would be different.

By the way, Schneider claimed it a suitable lens for close-up work.

bruce terry
4-Sep-2006, 17:33
And once you have generally focused and framed your subject close as you wish, move the entire camera/tripod combination forward/backward to fine-focus. Incredibly easier, once you find a secure way to move your three-legged beast.

JW Dewdney
4-Sep-2006, 21:21
Since you already have the lens, try it. I think you will be pleased with the lens performance whether it is the theoretical optimum lens for the purpose or not. There are so many other factors that affect the image quality in close-up work that I wouldn't consider anything else before giving what you have a good try. If it were an obvious inappropriate choice like a radically asymmetrical speed lens, that would be different.

By the way, Schneider claimed it a suitable lens for close-up work.

I'll second this statement - and summarize differently. For all practical ways of working, you will MORE THAN LIKELY find there to be no perceptible difference in quality between this and a very expensive, high-end macro lens. I'm not joking.

Capocheny
4-Sep-2006, 23:15
Gerry,

If you need a versopm of the "QuickDisc"... email me off-line and I'll send you one.

Cheers