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Ross Schuler
19-Feb-2002, 21:17
Hi I am very new to Large Format and I would like to know if I set my lens to F 4.5 and focus on the foregroung so it is sharp and then set my lens to F 32 to t ake the picture with some front tilt will the entire foreground and distant back ground be in focus in a landscape. I just ordered a copy of Simmons book to help me understand camera movements and focusing. Any help on this subject will be a ppreciated My lens is a 90mm 4.5 Ross

Steve Gangi
19-Feb-2002, 21:35
That is sort of what I do but not exactly. I focus and tilt with the lens wide open, and then I insert the film holder, stop down the lens and shoot. The details depend on your camera. If it uses base tilt, you use the little poem "focus far, tilt on near, then fiddle around till all is clear" or something like that. If your camera has axis tilt like mine, I focus at the center of the screen, and then slightly rack the focus back and forth while tilting until it's all sharp. Just remember, a little tilt goes a long way. Watch the ground glass, remember to lock down before inserting the film, and you'll be fine. It's faster to do it than to describe it. By the way, you won't necessarily need to use f32 all the time.

Douglas Gould
19-Feb-2002, 22:49
Ross,

I have Simmons' book, and have found it to be very well written and easy to understand. Your question will be answered in the book. I too am new to 4x5. I'm sure there are more thorough books, and more in- depth books, but as far as easy to read/understand, you'll be happy with this purchase.

He covers the movements of the camera and their effects/use quite thoroughly. I just read Adam's "The Camera", and ol' Ansel sure can go on about a subject. Simmon's gives you the same info in one third the pages.

So, I haven't answered your question, but help is on the way!

Doug Paramore
19-Feb-2002, 23:48
Ross: With the 90mm, you can focus about 12 feet in front of the camera and at f32 everything will be in focus. With wide angle lenses, you need to focus closer due to curvature of field of focus. If you don't "focus in", the center may be sharp but the edges will be soft. For longer focal length lenses, I usually focus about one- third of the way into the scene and then use lens tilt to bring the whole into focus. You may need to touch up the focus. I prefer to use rear tilts when shooting with a high horizon. Focus on the distant objects, then tilt the back of the camera to about verticle. This is, for me, the fastest method and the foreground near objects are made slightly larger. I like this effect for the feeling of depth it gives. Welcome to large format photography. It is a wonderful world.

Regards,

Lukas Werth
20-Feb-2002, 19:15
Sorry, but I have to disagree with the other answers. Focussing a 90 mm lens may work, to a certain degree, by just fiddling around, but for really sharp negativs you first of all need a magnifier to check, and you have to understand how the tilt (or swing) works. Simmons' (otherwise very helpful) book does not explain this properly, as I know from own experience. My beginner's mistake was to use too much tilt most of the time. Articles on this website may help; I learned focussing properly and in reasonable time from Harold Merklinger's book (check his website).

Mike Mahoney
20-Feb-2002, 21:02
Welcome to LF photography. You would set your lens to the widest aperture to give a brighter groundglass image for initial focusing, and recheck at the actual shooting aperture with a loupe and darkcloth.

You can make the whole focus and movements thing as hard or easy as you like ... Merklinger is certainly the hard way, perhaps made easier with a masters degree in math, although his website used to contain short video clips which are helpful.

Remember this little ditty .... " Focus on the far, tilt for the near, then focus and tilt 'till all is clear ". In your example, focus on the distant horizon, then tilt the lens panel foward, or the film panel backward to acheive focus on the near object. Bottom line is it isn't rocket science, and after a few hours behind the groundglass actually seeing the effect of movements, you'll get the hang of it. Others take a much more measured approach. Try simple first, and if you're not happy with your results, change your shooting method.

The Simmons book you have ordered is often mentioned as an excellent source, as is Strobels " View Camera Technique "

Perhaps the most valuable LF resource is this forum ... the archives are a goldmine of information, and the members helpful.

Steve Gangi
20-Feb-2002, 21:09
I neglected to mention a focusing loupe, but that is correct. A loupe makes a difference in final sharpness. I cheat some. Being so nearsighted, I stick my nose to the glass, and don't need a loupe until just before the film goes in ;) I didn't mention H. Merklinger, because he goes more into the heavy math and physics and not everyone is ready for that. For a quick rule of thumb, with a normal (150 or 160mm lens and 4x5 camera and let's say about 5 1/2 to 6 foot height and a level landscape, about 4 or 5 degrees tilt should be pretty darn close.

Lukas Werth
24-Feb-2002, 06:32
Just another clarification, before this thread goes into the archives: Merklinger is certainly also a very good help in case you have sleeping difficulties. I could not rehearse his math. BUT: it gives you a very good possibility at hand to focus any view camera very effectively with a minimum of movements in a minimum of time, and it tells you what is important, and why it is. The crux is the hinge rule, which says, in a nutshell, how much tilt is needed for a certain focal length for the plane of focus to pass in a certain distance below your camera. It takes some practice to estimate the best distance in any situation to get everything sharp before and behind the plane of focus (Merklinger has something to say about this, too), but once mastered, the days of fiddling around are largely over.

I normally tilt the front standart, and I taped a list of the necessary tilt degrees on each of my lensboards. But the method can be easily adapted for back tilts, as well as for swings (Merklinger even explains, at least basically, what happens if you tilt and swing at the same time).

I have read Stroebel's book, and I don't share the enthusiasm for it. It is a much more effective sleeping pill than Merklinger, and has little to say about focussing in practice.