Read upward. Your question has been answered.But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.
At some point you have to employ experience. Photography is not a lab experience.
.
Read upward. Your question has been answered.But that brings me back to how does one determine focus, from film plane or diaphragm, or a different point.
At some point you have to employ experience. Photography is not a lab experience.
.
Hyperfocal focusing is not exact enough for it to make any real difference if you measure from the lens or the film plane etc
Thanks for giving a link to the spreadsheet. I set the focal length to 90 mm, used blur circle = .1 mm, looked in the f/22 column. Hyperfocal distance is 12.08' as you reported. I set that in one of the focused distances, got near and far limits of DoF as 6.99 and 44.30 feet respectively for that focused distance. Spreadsheets are handy that way, one plugs numbers into the right cells and others recalculate to conform.
Schneider uses a blur circle, conventionally called Circle of Confusion, of 0.100 mm for 4x5. This will barely allow contact printing, won't allow enlargement. Remember that the amount of blur that can be tolerated in the negative depends on how much it is to be enlarged.
Do you have any books on LF photography or optics? If not, you'd do well to get at least one good book on LF photography and study them. You'll learn more from any of them than by asking questions here. The two that are most recommended here are Steve Simmons' Understanding the View Camera and Leslie Strobel's View Camera Technique. Both are available through sellers who list their wares on, in alphabetical order, abebooks.com, alibris.com, amazon.com, ... at very reasonable prices. Interestingly, the French LF forum recommends Jim Graves' A user's guide to the view camera.
I'm not sure which book on optics offers a good combination of price and usability. You might want to look for Arthur Cox' Photographic Optics. Rudolf Kinglake's A History of the Photographic Lens is sometimes touted here but the last time I looked it was hors prix. His Lenses in Photography might be helpful and less expensive.
I own a copy of Ansel's three books but I will try to get my hands on your recommendations. Thank you.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Technicians have formulae for DOF. Photographers also have to consider their subjects and how the image will be presented. The dreamy nudes of Anne Brigman certainly didn't demand meticulous attention to DOF. In some of Edward Weston's macro-photographs, an extremely small aperture masked the limits of any calculated DOF. We have to balance science with art.
I've solved my issues by just stopping down to f32.
Worthy of printing and taping to the camera or meter...
But just to play devil's advocate, if one in the field insists on determining DOF, precisely and accurately, down to the nearest decimeter – let alone centimeter or millimeter – how much art is it going to take to "balance" this?
I applaud this K.I.S.S. approach, but just be sure that f/32 doesn't become an auto-pilot switch.
Well for this particular subject matter f32 is necessary for my artistic vision. I don't like the idea of 8-17 minute exposures though so that's a tradeoff In will need to see if I can live with.
Bookmarks