Assessing sharp focus on the GG require a good loupe (4x to 7x, more is not better), good dark cloth and a learned skill. Practice, Practice, Practice as with any developed skill this will be difficult initially and will improve with time and development.
Bernice
Originally Posted by JohnF
You are welcome. If you use my method, the focus will probably be right where Doremus' method will land you. I believe my way is just a visual way of doing the same thing (as I have not had the scales on my cameras and I learned about that method late). I have used the method Doremus mentioned with the 11x14 to help get me very close...that much real estate is not easy to manage.
To aid my eyes, I have racked the focus in and out to help judge when something is in perfect focus on the GG. But f64 and be there!
"Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China
Thanks Bernice and Doremus - really helpful. Now to get back to that tree. Oh, it has started a week’s worth of rain here in the north of England. Guess I am going to have to set up some indoor focussing challenges!
So a little indoor practice today. I fixed a centimetre scale to the bed of my Wista 45DX, and estimated the distance between near and far focus on the scale.
For near infinity far distance, I moved the focus to 1/3 way in, and for macro focus half way, assessing the effect as aperture stopped down in stages, as described above. It did, of course, work very well as you all suggested. Very satisfying. Also added in some swing and tilt on a receding wall. It is starting to feel more intuitive. Thanks once more, one and all.
With the "near-far" focus technique, you should always position the focus at a point on the (nice new) scale you have on your camera bed halfway between the near and far extremes. It makes no difference if you are working close or far.
The whole "focus 1/3 into the scene" method is used with actual camera-to-subject distances and is really just an approximation of where the plane of sharp focus is positioned anyway. So, if you've got a 4mm focus spread, you'd position the focus right in the middle of that, i.e., at 2mm in from the extremes.
I use Wista DXs and SWs too, FWIW, and use the engraved lines on the brass rail as reference marks on my scales.
Best,
Doremus
There are limited controls available for controlling DOF. View cameras have one that smaller formats lack, and that is camera movements.
My experience is not everyone's experience; my work isn't what everyone does. And all the rest of the disclaimers. That said, I found that for me there were just four main ways to control DOF. My order of preference:
1) Camera movements. First thing I would do is place the plane of exact focus where I wanted it to be. The art in this is defining the concept "where I wanted it to be" for your own work. It's often not intuitively obvious, and it takes practice -- but mostly learning how to do this takes a lot of film. The more photographs you make, the better you get at it. It took me hundreds of sheets of film before I felt like I really understood how to use camera movements. But every photographer learns in his/her own way and own time.
2) Aperture. Once the plane of exact focus is established, I pick an aperture that will give me sufficient DOF (on *both* sides of the plane of exact focus). Depending on the composition and what I want from it, I would often go an extra stop. I determined a long time ago that diffraction was nearly meaningless for me in LF, but things being in focus and/or out of focus could make or break an image. So I was always willing to stop all the way down if that's what the image needed. Group f/64 wasn't wrong. Just sayin'.
3) Perspective. Said another way, where you place the camera. I hardly ever positioned a camera with DOF in mind; only the image mattered.
4) Lens choice. For a given camera position and subject position, shorter lenses give you more DOF than longer lenses. That said, I hardly ever did this -- I always wanted to keep cropping to a minimum.
Within this limited palette of controls there is a huge range of possibilities.
Bruce Watson
But you left out the most important step.
Learn what point to focus on.
That is perhaps the most difficult thing. Many an LFer starts out thinking that the plane of exact focus needs touch the main point of interest in the photograph. But if you make enough photographs to learn how movements work, you sooner or later disabuse yourself of that idea. It's hard for newbies (and not a few oldsters) to wrap their heads around the concept: Just because it's the central point of interest of the photograph doesn't mean it intersects the plane of exact focus. Or is even all that close to it. Can be, but doesn't have to be.
Bruce Watson
“4) Lens choice. For a given camera position and subject position, shorter lenses give you more DOF than longer lenses. That said, I hardly ever did this -- I always wanted to keep cropping to a minimum.”
Bruce, it’s easy to take for granted that a wider Angie lens gives more DOF, but in reality, at the same aperture and the same magnification, all lenses have the SAME DOF. So if you use 90mm or a 300mm, if the subject fills the frame exactly the same amount, DOF will be the same, though perspective differences caused by different angles of view will be obvious.
This is an important understanding when you are attempting closeup work in particular, often overlooked.
Another suggestion is to look under the dark cloth with your loop and carefully look at the area in focus as you stop down the lens. For all practical purposes, the view gets too dark beyond F 16.
Adjust your point of focus accordingly.
Be a contrarian when necessary and stop down to f 45 or more if it gives you the image you imagine.
Pdm
Leslie Stroebel publishes the following table in the latest edition of View Camera Technique.
Distance ration is the ratio of len’s to near focus and lens to far focus, and focus fraction is the ratio of travel of the lens on the camera bed from the near point as a fraction of the total travel from near to far points:
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