close-up work maximum depth of field
Hello. I am shooting a close-up photo with a 4x5 sinar. I have a choice of 3 lenses, 90, 150 and 210. I need to fill the frame with an object roughly the size of an orange and I want to get as much depth of field from front to back on all sides of the object (so tilts and swings are irrelevant as far as I can tell.) I can shoot f64 since I am working with strobes.
I am TRYING to avoid using the 90mm. since I want to minimize distortion as much as possible.
As far as I can tell from using a depth of field calculator: http://www.rbarkerphoto.com/DOF2.html (pretty great resource) I essentially have less than an inch of DOF with any of my lenses.
Are there any tricks or advice on this or am I limited by the nuances of the medium?
Many thanks as usual for your thoughts on the matter.
Best,
Serge
close-up work maximum depth of field
Are there any tricks or advice on this or am I limited by the nuances of the medium?
No, you are limited by the laws of physics.
There are a number of things you can to do get a more acceptably sharp print. You can back off and not fill the frame (that is, get farther away from a 1:1 magnification). You can use smaller apertures (DOF will improve, but sharpness will actually decrease). You can print smaller. Etc.
It won't matter which lens you use - at a given magnification, DOF will be the same for all lenses as you found from the DOF calculator.
Without knowing more about what you are trying to acomplish, that's about all I can tell you.
close-up work maximum depth of field
if the object is a cube then tilts and swings are not irrelevant.
If you can only see one face of it then required dof would be very little.
if the object is a sphere then the dof only needs to be 1/4 the diameter of the sphere, unless the object is transparent (glass).
i.e. the shape and substance of this theoretical object may well require less dof than you think and tilts and swings may well help out but without knowing then all advice is guess work.
So what is it?
close-up work maximum depth of field
Bruce said it.
I gather you want to shoot a relatively deep object at a magnification on the order of 2:1. Short answer, as Bruce said, you can't get it all in focus and stopping down to f/64 will lose more sharpness than it gains.
For a longer explanation of what can and can't be done and how to do what's possible, buy a copy of Lester Lefkowitz' book The Manual of Closeup Photography. Out-of-print, available used through, in alphabetical order, www.abebooks.com, www.addall.com, www.amazon.com.
close-up work maximum depth of field
it occurs to me that the effective aperture will be vastly reduced at 1:1 magnification. Question is, will this increase effects of diffraction? Probably. Since f64 will be closer to the optimum sharpness of a 210 lens than a 90 lens, then the 210 may give better actual dof rather than theoretical. I'm just thinking aloud here so anyone with better lens theory than me might like to comment. They might also like to comment on whether the dof field calculator includes that in the maths.
close-up work maximum depth of field
Do you actually need to fill the frame? Remember, you have a tremendous amount of film here. If the final result will be printed, then don't bother filling the frame, just go for best sharpness.
close-up work maximum depth of field
Serge:
If the object you're photographing is opaque, you might consider scanning light photomacrography (a.k.a. "zero-perspective" imaging). You get high resolution and unlimited depth of field by passing the subject through a narrow beam of light while the shutter is open. There used to be an expensive commercially available system for this kind of illumination called the Dynaphot, but some people have improvised their own; see
http://www.modernmicroscopy.com/main.asp?article=60
I have read descriptions of using three Ektagraphic projectors with slit apertures for light, and a relatively cheap motorized stage to move the subject through the light beam. It requires some trial and error, but the results can be spectacular (see the fly head photograph near the end of the Modern Microscopy link).
Good luck.
-- J. Packer
close-up work maximum depth of field
If anyone can tell me how to get dof figures out of this software I would appreciate it.
www.winlens.de/en/wl43_intro.html
thanks
close-up work maximum depth of field
Found it. Its part of "show extra information" . i.e. check box for this should be on.
close-up work maximum depth of field
you can also shoot several sheets at different distances from the object, then scan them, put each in a separate PS layer and erase all the out-of-focus portions from each image. It is important that you move the entire camera-set-up (or your orange), and do not change focus on the camera. There is also a program called auto-montage, not cheap (3 grand or so), that does the same thing. I think there are also routines for NIH image to do that kind of a thing on the cheap side.
Daniel