The longer focal length lens didn't allow me to get closer !greenspun.com : LUSENET : Large format photography : One Thread |
I'm quite confused. I have a 14" Red Dot Artar in a barrel and recently purchased a 19" Red Dot Artar in a barrel. I have a Calumet C-1/C-3 that I thought had a 30" bellows draw, but the camera only allowed the bellows to draw at 22-23".Anyway, when using the 14" lens, I wasn't able to get as close to my subject (I do still life photography), so I purchased the 19" thinking that I could get in closer. But I noticed that I can't get any closer to my subjects and focus well. Why? Am I totally confused about lens optics? I thought the longer lens would allow me to get closer. I'm disappointed.
Any suggestions? Do I have to go to a 500 - 600mm lens?
Thanks for any help.
Ron
-- Ron Whitaker (rgwhitaker@yahoo.com), October 16, 2000
The longer the lens, the greater the draw required to close-focus.
-- Jack Chase (jgchase@tenet.edu), October 16, 2000.
One of the peculiar things about close up work with a view camera is that the image magnification keeps changing as you attempt to focus. What can make it easier is to move the whole camera toward or away from the subject. Fortunately, you can do this to a degree with the C1/C3. By loosening the two knobs that clamp the camera to the base, you can slide the whole mess back & forth. Just make certain the base is screwed tight to the tripod head and that your head is up to the task of supporting an unbalanced load. My Majestic 1400 works real well in this regard. As to your bellows length problem, I'm puzzeled. I have a 19" Apo Artar on my C1 and have easily done 1/2 life size with it. As far as closeup work with short lenses goes, I just did some 1/2 life size with a 203 f7.7 Ektar and had no problem at all. I could have gotten even closer with ease. Try moving the whole camera and see if that helps. And let us know how you make out.
-- Robert A. Zeichner (razeichner@ameritech.net), October 16, 2000.
Ron, yours is the second C1 I've heard of with a "short" extension, so I guess it may have been somewhat common to replace a worn bellows with a shorter one, or Calumet delivered some of these beasts with shorty bellows. Who knows?A 14" lens extended 21" gives you 1:2 magnification, or an image of an object measuring 16"x20" on the 8"x10" ground glass. The situation is worse with the longer lens, i.e., you won't even get to 1:2.
I'm saving for a Wisner 8x10, because I've gotten spoiled by 21" on my cheapy 4x5 rail...
-- John O'Connell (boywonderiloveyou@hotmail.com), October 16, 2000.
Ron,You seem to be saying the draw is restricted by the camera rather than the bellows? I don't mean to ask an insulting question, but you are aware that the rear rail, the one that folds up, has an inner extension, right?
There should be three sets of knobs back aft, one for the rear frame or standard, one for the tripod block, and one for the inner extension. When run out all the way backwards, you should have 34" of draw, measured from the center of the g.g. to the edge of the lensboard opening.
-- Sean yates (yatescats@yahoo.com), October 16, 2000.
At 1:1 (lifesize) the bellows extension is twice the focal length of the lens. This means that the image circle diameter is doubled as well,(and the aperture number is doubled too! ie. f/11 becomes f/22).
A 150mm LF lens will easily cover 10" x 8" at lifesize or greater, and needs only a 12" bellows draw.
You can work out the coverage from the rule-of-thumb formula; D = F *(m+1). Where D is the diameter of the image circle, F is the focal length of the lens, and m is the magnification (0.5 for half lifesize, say).
Why not get a 300mm Symmar or similar 'standard' lens for 10 x 8? This gets you to about 3/4 lifesize, and has bags of coverage for camera movements.
-- Pete Andrews (p.l.andrews@bham.ac.uk), October 17, 2000.
Simply put, to get closer when your camera or bellows limits you, you need a SHORTER length lens, not a longer one.
-- Charlie Strack (charlie_strack@sti.com), October 17, 2000.
Hi Ron, like Sean said, you seem to state you have bellows, but the camera won't let you extend them? Did you loosen the two black star knobs and extend the upper rail track all the way back? Best, David
-- david clark (doclark@yorku.ca), October 17, 2000.
Ron, Everything has been said only just one more word, given the same bellows length, shorter focals give bigger reproduction ratio, When using long lenses you might not be able to get close and focus Good luck
-- Andrea Milano (milandro@multiweb.nl), October 18, 2000.