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coops
21-Jul-2008, 20:12
Recently got a nice use Tachihara 4x5, my first ever film camera, and had a few shots drum scanned. The distant areas of the image were not as sharp as I thought they were, and am a little confused as to how to focus. I shoot landscapes.
A few tutorials I did read required the rear standard be tilted back a little, but I don't think this camera does that. I think I understand the concept of the Scheimpflug principle, but doing it is driving me nuts.
Of course I live in Florida and it must get to be 175 degress under the blackcloth and my glasses fog up, but I am willing to keep at it but would like to hear what steps you guys to get the best focus.

Cheers

Glenn Thoreson
21-Jul-2008, 20:31
I rarely use any camera movements for landscape photos. A depth of field chart for the lens you're using may be helpful. Barring that, find your principal object of interest, focus on that aand stop down to at least f/16. No principal object in the scene? No problem. Focus about a third of the way into the scene and stop down. You will find you need to stop down to smaller apertures with large format than with small formats in order to get the depth you want. Stops of f/22 and smaller are the norm for a lot of things. Tilting the back affects perpective. Tilting the front will affect the close object focus as much as anything. You still need to stop that lens down. Have fun! :D

Bill_1856
21-Jul-2008, 20:37
Forget Scheimpflug! Just get a good loupe to check the ground glass, and close the aperture down far enough to give the depth of field you want.

coops
21-Jul-2008, 20:55
Forget Scheimpflug!


Who?? Thanks guys, good advice. I am trying to make things more difficult than they should be.

Jon Shiu
21-Jul-2008, 22:51
Hi, the tachihara does have tilts on back. Loosen the two knobs that allow the back to tilt and push them out of the zero detents with your thumbs. Just practice a while and you'll get it. It really is kind of a fun thing when you realize you can get near and far in focus at the same time!

Jon

Bill_1856
22-Jul-2008, 02:44
http://bobatkins.com/photography/technical/dofcalc.html

Ken Lee
22-Jul-2008, 03:59
Practice indoors, using near/far objects on a table top. Some times, you will want to combine tilt with other movements.

In this image (http://www.kenleegallery.com/html/tech/KitsBarn.htm), made with a Tachihara and a 150mm lens, it was necessary to use some tilt, swing and shift - in order to get everything in focus. If you look carefully, you see that the camera is actually looking off to the right, not straight ahead. The plane of focus goes from the lower left-hand corner, to the upper right-hand corner. I put the grass in focus at one extreme, and the building in focus at the other. Stopping down to f/22 was enough to bring the rest into focus.

The image was shot at f/22, to use the best aperture (http://www.kenleegallery.com/html/tech/rodenstock150detail.htm) of the lens, rather than stopping down all the way. That's why we go to the trouble of carrying these cameras around: they give us view camera movements. And we some times pay good money to get good lenses, which generally perform best a few stops from wide open - not past their limit of diffraction. f/64 may be fine for contact printers, but not always ideal for the rest of us.

Once you get the "swing" of it, you will have a lot more fun. You want to practice enough so that when you're in the field, it's second nature. When shooting the image above, I had to perform all of the movements in quick time, since the light and the fog was changing rapidly. That was not the time to learn about the camera, but rather to be shooting.

Instead of a loupe, a pair of strong reading glasses on a string, can be very handy, and not as easy to lose, misplace, or drop. They just hang from your neck, there when you need them. You can get them at an affordable price, at your local pharmacy.

Adam Kavalunas
22-Jul-2008, 04:44
Who ever says to forget movements is ridiculous. There are 2 main advantages to shooting LF, a large film area, and movments. Throw one away, and you're wasting half the camera! I use a Tachi. Loosen the back knobs, hold the back of the camera with your thumbs, pull in the rear guides towards you, like you're trying to pinch the guide and the back together, and it will release and allow you to tilt the back standard forward and backward. I also recommend getting a good loupe atleast 4x and checking the GG before you take your shot to make sure that as much as possible is in focus (if that's your goal).

Adam

svlindbe
22-Jul-2008, 04:46
Instead of a loupe, a pair of strong reading glasses on a string, can be very handy, and not as easy to lose, misplace, or drop. They just hang from your neck, there when you need them.

Ken, I have a pair of reading glasses. My experience is, they are more useful on my nose than dangling from my neck... :-) It is possible I have missed something, but I find it easier to view the whole focusing screen (4x5") at once for evaluating sharpness than using a loupe. A pair of glasses for short distance focusing are very useful.

Svein

Bill_1856
22-Jul-2008, 05:31
Who ever says to forget movements is ridiculous.

That's strange -- I don't FEEL ridiculous.
Have a look at Coop's excellent wildlife portfolio, with its superb use of selective focus. I don't think that he needs to consider the formulistic Scheimpflug approach to depth of field, since he obviously has already developed a more than satisfactory visual approach.
Landscape photography, particularly here in Flat Florida, doesn't take a lot of "movements." If, in the unlikely event that stopping down isn't enough, then just a couple of degrees of front tilt with the lens, or back tilt with the film is all which is ever required (neither of which is easily available on my Crown Graphic).

Jack Fisher
22-Jul-2008, 07:05
My dark cloth is black on one side and white on the other. Using it with the white side out reflects some of the heat.

Brian Ellis
22-Jul-2008, 08:14
First, your camera does have back tilt. If you think it doesn't then you need to spend some time learning what your camera will do before you start making photographs. Your camera has back tilt and swing and it has front tilt, swing, rise, and fall, which are all the movements you need for landscape and most other purposes. It doesn't have front or rear shift (not sure how Ken made his photograph with a Tachihara using shift, maybe I missed something in his message) which I never found to be a problem, I just moved the tripod.

Second, by far the best and easiest method IMHO for focusing a LF camera (and determining the optimum aperture to use to get the depth of field you want) is described in the article about focusing written by Tuan in the articles section of this site, which I'd suggest you study carefully. The basic concept is to focus on the nearest object that you want to appear sharp in the photograph, then focus on the farthest object that you want to appear sharp, then set the front standard half way between them (assuming you're focusing with the front, which you will be since a Tachihara doesn't have rear focus capability). Use a depth of field table to determine the optimum aperture to use to get the depth of field you need, which is determined based on the distance your front standard moves when focusing on the near and far objects. It helps to tape a paper or cloth milimeter ruler along the side or top rail of the camera so that you can tell how far the front moved when you focused on the near and far objects and where the mid point between them is.

If you don't have a depth of field table handy, here's an easy way to remember the appropriate aperture without consulting a table. If the standard moves approximately 1 mm use f11, if it moves approximately 2 mm use f22, if it moves approximately 3 mm use f32, if it moves 4 mm use f45, etc. These numbers are based on the Linhof depth of field table plus one additional stop in case you want to enlarge beyond the 8x10 print size on which the table is based.

A few other points: I never liked the suggestion to "just look at the ground glass." That may be fine in bright light but when you're in dim light and trying to check depth of field at smaller f stops you won't be able to see well enough to know what's going on. I also didn't like the suggestion to "focus a third of the way into the scene." With landscape it's usually impossible to know where a third of the way is, plus that doesn't work well even if you can figure out where one third is because how far into the scene you should focus varies depending on the focal length of the lens you're using. Finally, IMHO the absolutely worst way is to just fiddle around until you get the camera focused as best you can and then stop way down to insure that you have enough depth of field to make up for any focusing errors. Among other problems, that "method" usually leads to unnecessarily small apertures and therefore unnecessarily long exposures plus perhaps giving rise to diffraction problems if you're making big enlargements.

Glenn Thoreson
22-Jul-2008, 12:04
I'm pretty much in agreement with Bill-1856. And I don't feel ridiculous, too. The majority of my 4X5 is done with a Speed Graphic. I use the front rise to eliminate unwanted foreground and that's about it. I seem to be able to get nice photos without all the other things. And Coops, if you need near and far in sharp focus, all you need to do is focus far and (front) tilt near. It's easy. Keep juggling back and forth until it looks right to you. It doesn't require much front tilt to do it. About 5 degrees or so will do it. I think I'll go join the f/64 group, now. :D

E. von Hoegh
22-Jul-2008, 12:50
Recently got a nice use Tachihara 4x5, my first ever film camera, and had a few shots drum scanned. The distant areas of the image were not as sharp as I thought they were, and am a little confused as to how to focus. I shoot landscapes.
A few tutorials I did read required the rear standard be tilted back a little, but I don't think this camera does that. I think I understand the concept of the Scheimpflug principle, but doing it is driving me nuts.
Of course I live in Florida and it must get to be 175 degress under the blackcloth and my glasses fog up, but I am willing to keep at it but would like to hear what steps you guys to get the best focus.

Cheers

Use a focussing loupe and pay attention to all of the groundglass!. If the groundglass is in the right place, and it's sharp on the Gg, it will be sharp on the film as well.

Sheldon N
22-Jul-2008, 13:44
Having a drumscan done and then viewing the images on your computer at 100% is about the most stringent method for finding focus errors. If you are looking for critical sharpness using this method, stopping down alone is not going to accomplish this for near/far compositions. You will either have insufficient depth of field or you will have loss of sharpness from diffraction due to stopping down too far.

I would recommend getting a good loupe such as a 6x and focusing very, very carefully on the ground glass. Get both the desired near and far points of the composition in perfect focus simulaneously, and keep in mind how to most efficiently use the "wedge" of focus you get with the scheimpflug approach. Then stop down to a reasonable figure (f/22-f/32) to get sufficient depth of field for your shot.

Try getting something like a BTZS focus hood that is white on the outside to help you keep cool while focusing. Hold your breath while under the darkcloth to keep things from fogging up as much as possible.

coops
22-Jul-2008, 21:21
Thanks for all the great feedback, I appreciate it. I do have a better focus hood on the way and a better loupe, and will try all the suggestions.
Thanks again

Allen in Montreal
26-Jul-2008, 10:12
Thanks for all the great feedback, I appreciate it. I do have a better focus hood on the way and a better loupe, and will try all the suggestions.
Thanks again


When I started using a view camera, I found this very helpful, you may want to do something similar, at least for the short term.

I picked up a mid sized address book, replaced the letters with key quick cheat sheets.

B became Bellow Draw and I worked out and transcribed the bellows factors for all the lenses in my bag.

D became a home made Depth of Field chart.

F became filter factors, for all the filters I use.

And so on. It is very handy little reference book to have in the field, and even more so in the beginning. I still use mine as I use the camera only occasionally and some of these tables are far from being burned into my memory. :mad:

Leonard Evens
26-Jul-2008, 17:57
You've gotten lots of advice, most of it good, some of it not so good, and certainly with all that you've been told, you may be confused.

Brian Ellis gave you the best advice advice by far. You should read the article he referred you to at lfphto.info, but his summary pretty much told you what you need to do. Let me say it once again. Focus on the nearest thing you want in focus, note the position of the standard on the rail, then do the same for the furthest thing you want in focus. Then focus halfway in between. You don't have to get it precisely right. His rule for determining the proper f-stop is fine too, but it may lead you to stop down a bit too far. He is using a more stringent criterion for sharpness than I consider necessary. My rule is to multiply the focus spread by ten and divide the result by two. So, for a focus spread of 3 mm, you would stop down to 30/2 of about f/16. Brian recommends f/32, which will work better if your pictures are going to be examined by people who like to get up close and examine detail. But if you do what he said, you won't go wrong.

I also agree with Brian that you can't necessarily rely on the ground glass to see what is in focus after you stop down. Even in relatively bright light, few people can see much of anything beyond f/16 to f/22. One way to help is to use a 4 X or stronger loupe, but that may lead you to stop down perhaps as much as two stops more than you have to. (The explanation for why that is true is too hard to explain here.) In landscape photography you usually don't want to stop down any more than you have to because every extra stop requires doubling the exposure time. If anything is moving in your scene, such as leaves rustling in the wind, that will produce some blurring in the image.

But there is another approximate rule that can help you when you want everything out to infinity (very distant points) to be in focus. That is often the case for landscapes. In such cases, doubling the f-number halves the near distance that will be in focus. So if everything is in focus from say 30 feet to infinity when you stop down to f/11, you can be reasonably sure everything will be in focus from 15 feet to infinity if you stop down to f/22. Unfortunately, it is much more complicated in general.

As to tilting the back, generally speaking, you shouldn't do it, unless you know what you are doing and you have some specific aim in mind. Keep in mind that tilting the rear standard back is the same as turning the entire camera upward and then shifting the frame up. Tilting the rear standard down, is equivalent to tilting the entire camera downward and then shifting the frame down. Both lead to distortions of shapes. For example, if you tilted the rear standard back in a landscape, vertical trees would tend to converge towards one another.

It is best to keep the back vertical, and tilt the front standard when appropriate. But you should wait until you throughly understand what to do with both standards in their default positions before trying that. Then do some studying. I would be willing to bet that if you think you understand the Scheimpflug Rule, then you don't. Most beginning view camera photographers think that the Rule gives you much more than it actually does. To be used properly, it must be combined with the Hinge Rule, but I won't go into that here.

Finally, let me comment that the one third into the scene rule is nonsense for any landscape in which you want everything out to infinity to be in focus. What, if anything, is one third of infinity supposed to mean? The fact of the matter is that there is precisely one case in which that rule applies, and it is not one often encountered in landscape photography. About the only useful insight you might gain from it is that for scenes with many distant points of interest, the rear depth of field will be significantly larger than the near depth of field, but almost never twice it.

Good luck.

CG
26-Jul-2008, 21:49
One more vote for the value of using a loupe to really see what the focus looks like. Especially if you are planning great enlargements. The loupe will mercilessly reveal whats fuzzy - before you trip the shutter.

Practice does in this case make perfect. Without intending to use any film, just set up a camera and focus it on near / far combinations of subject matter, then turn the camera in another direction and focus on something else, and just do it over and over. If you practice enough, you'll get faster and more sure of what you are up to.

It usually only takes a tiny tip of the front standard to get things right. The enormous movements one sees in texts on the extreme ranges of view camera movements are rarely if ever used.

C

Leonard Evens
26-Jul-2008, 22:21
Let me add some more words of caution about using a loupe. First, as I noted previously, if you use it to judge depth of field as you stop down, you may end up stopping down too much, thus making subject movement more of a problem. But even before that, you shouldn't use a loupe much more powerful that 4 X. The reason is that under too much magnification, you will be looking at the surface of the screen rather than the scene itself, and you will actually find it harder to focus.

I had special reading glasses made for me which allow me to look at the gg from about 6 inches. This gives me the same perspective as looking at an 8 x 10 print from about 12 inches. Since I use the near point, far point method outlined by Brian, that is more than good enough for accurate focusing, and I almost never need higher magnification. I seldom have focusing problems. I also have a 3.6 X loupe, which I sometimes use in tricky situations, and I have a 7 X loupe, which I almost never use.

One thing you might consider in getting a loupe is whether or not it can be tilted. A loupe with that capability is much easier to use near the corners and edges, which can sometime involved critical detail. I believe that Sylvestri makes such a loupe.