Simple focus questions

[Meekyman]

Hi Folks,

New to LF cameras so please be patient with me!

I have read the LF guide to focusing the view camera and been on a one day introductory workshop, so understand and have put into practice the idea of using tilt to get good back to front sharpness. So, armed with this I trotted out to a wood yesterday with the aim of actually taking a few photos but came back really frustrated as I found it very difficult to focus, nigh on impossible in some situations.

Obviously, in the wood there were many trees! I came actross one composition with a yellow leaved tree sandwiched between bare trunks in the distance with a pair of bare trunks forming an "L" shape, framing the photo, in the foreground. Focused nicely on yellow leaved tree in the distance, could focus on horizontal part of pair in the forground, but much as I tried I could not get all the vertical "L" trunk in focus. OK, maybe this was impossible to focus with movements and I just had to stop down a lot...tried that, but not better, so move on....what could I have tried?

So, next composition, trees in distance with line of trunks leading towards the focal point. This time I place the nearest vertical trunk so it was not occupying the whole of the vertical, but still hard to focus. I tried a little swing as well as tilt and just became a mess.

I'm going to set up a whole lot of jars and bottles on my dining table and practice, practice, practice focus but maybe I just set myself too hard a task for a beginner?

Graham

[ic-racer]

Whenever the front and rear standards are not parallel there is LESS depth of field. Many difficult depth of field problems can be navigated by ensuring front and rear are parallel and stopping down based on the focus spread using popular DOF heuristics.

http://img.photobucket.com/albums/v670/ic-racer/2012/DOF-1.jpg

Image ©Harold M. Merklinger from Focusing the View Camera.

[Lenny Eiger]

I have read the LF guide to focusing the view camera and been on a one day introductory workshop, so understand and have put into practice the idea of using tilt to get good back to front sharpness. So, armed with this I trotted out to a wood yesterday with the aim of actually taking a few photos but came back really frustrated as I found it very difficult to focus, nigh on impossible in some situations.

Obviously, in the wood there were many trees! I came actross one composition with a yellow leaved tree sandwiched between bare trunks in the distance with a pair of bare trunks forming an "L" shape, framing the photo, in the foreground. Focused nicely on yellow leaved tree in the distance, could focus on horizontal part of pair in the forground, but much as I tried I could not get all the vertical "L" trunk in focus. OK, maybe this was impossible to focus with movements and I just had to stop down a lot...tried that, but not better, so move on....what could I have tried?
Graham

Graham,
First of all, welcome to the world or large format. This has been discussed to death, but the first thing to take a look at is the presumption that f22 is any sharper than f45. This might vary a little from lens to lens, but most here would agree that the difference is minimal, if not miniscule. If you want some depth of field, close down....

You have to realize that large format attracts different types of photographers. Some are interested in the extra tonality one gets with a large negative, others are engineering types that do their best to achieve some sort of perfection. They plot charts, do all sorts of experiments that are quite helpful to the rest of us. When shooting tabletop, that stuff is critical, but going outside is another matter.

One of the things people first do when they discover the zone system is they try and push its limits. They usually shoot an indoor shot with a bright window in it. There is no way to solve that much of a difference between the quality of light inside and the light outside. If they succeed, whether by development or Photoshop, they have to realize that the photograph was about this and not about something deeper. Technical exercises are not that interesting to the rest of us. It appears you may have been doing the same with depth of field...

These things all work, but within reasonable limits. Everyone shoots differently, but I don't use swings and tilts on every shot, probably only a third. Every once in a while its useful. The better strategy is to focus about a third of the way in to your shot and close the lens down. Then you won't have the "came back really frustrated" scenario. You will at least have your photo, and over time you will learn where the edges are.

Best of luck,

Lenny

[Vaughn]

I photograph in the forests quite often. It can be a fun challange to bring a little order from chaos. But swings and tilts are difficult to use because of all the blasted trees! If it were not for all the trees, photography in the forest would be a breeze!

But once I have the general composition settled in, I set up and level (approx) the camera, get it on the GG (and sometimes it ends up very different then originally thought), then I'll check the back tilt to get the trees pointed where I want them to point, then check the front tilt to bring everything back into relative focus. I'll check that third redwood back and make sure it is sharp from roots to 100' up the trunk...that tells me I got the GG and the lens zeroed out. I might use some front tilt if I have something close in the foreground -- but because this throws the upper portions of the trees out of focus, I'll have to make sure that they can be brought back into focus when stopping down. Occasionally some front swing can be used for the common good.

It is a little tougher to do in the lower light of the forest, but I start closing down the lens, paying attention to the out of focus areas. If I have placed the plane of focus in the 'right' place and tilted it just right, then as I close down the lens, I should see the depth of field expand evenly. That is, the closest thing should come into focus at the same fstop as the farthest thing. If the foreground comes into focus at f16, but the background at f32, then perhaps I should consider focusing a little further out and have them both come into focus at f22. Or perhaps a little more or less tilt, and see how the top and the bottom of the image come into focus together.

I just developed a negative last night that I had exposed the day before on a friend's property. It was a matter of picking just the right place for the plane of focus, and closing the lens down. The image was a small recently cut opening in the forest with a trail -- a jumbled mess that was challenging.

It was a 4 min exposure at f64 (didn't need f90) on FP4+. I did not have a watch, so I had to guess, but got talking to my friend, so it might have been 10 minutes...well adjusted for reciprosity failure...LOL! The neg looks great! Developed for carbon printing. I have one more to develop...I tried again to make it 4 min, but got to talking again and helping to fold up some tarps...and it might have been 15 minutes, but the light was dropping, too. So, there are some interesting possibilities...I could hold back on the development and get a nice negative for platinum printing.

[Chuck P.]

A good exercise in using tilt that brings home the concept quite well IMO, is to put a short object, maybe a flower pot, on the floor, say 10 feet from the wall---on the wall should be photograph or painting. At wide open aperture, now try to bring the center of the floor object and the center of the wall object in focus at the same time by using tilt, stop down till the shorter floor object and wall painting is completely sharp from top to bottom. Like you see in the diagram, when the lens is tilted, the DoF cone is shallower nearest the lens, hence the need for the foreground object to be shorter. In a forested environment i.e., highly 3-dimensional, tilt can be problematic, unless there is a lot of clear space between what you want sharp in the near elements and what you want sharp at the far elements.

[C. D. Keth]

Another demonstration that I did in school goes like this:

Get a full sheet of newspaper, some string, some tape, and a big sewing needle. Thread a piece of string through each corner of the newspaper and tape the string to the ceiling and the floor so it suspends the newspaper at an angle other than parallel to the floor and ceiling. The exact angle doesn't matter. Set your camera up and, wide open, use tilt to bring the whole sheet of newspaper into focus. Note how much of the string above the newspaper is also in focus and place pieces of tape at the points where the string appears to go soft to your eye. Stop down a stop and take note of the string that's in focus and do the tape thing again. Do it again and again until you're at the smallest stop. By looking at the string that is in focus at each stop, that helps enormously to be able to visualize exactly what you are doing when you tilt or swing a lens and stop down, or don't.

[Simon Liddiard]

Hi everyone,

As a LF beginner I am very grateful for Meekyman starting this thread, not to mention everyone who has responded! I find this forum to be consistently helpful.

Cheers,

Simon

[Meekyman]

Thanks everyone for your thoughts and time.

I guess I got myself wrapped up in the idea that tilts and swings could sole everything! I'd read that tall objects in the foreground running through to the background are tricky to focus with tilts and swings and you just have to place the focal plane in the "right" place and stop down, like a smaller camera without tilts and swinsg.....well guess I just experienced that! As it was my first real outing with the camera, guess I just wanted an easy life!!

I have Jack Dykinga's book at home and there's a photo in that where you have a tree canopy sweeping across the foreground with a river running diagonally across and autumnally coloured trees in the background. I guess here, tilts and swings would be detrimental too? I guess I have to learn to spot compositions where tilts/swings would be advantagous and where I'm better off without them?

Thanks for all the suggestions....I'll definitely play with the flowerpot/painting on the wall idea.

Cheers

Graham

[Vaughn]

Graham, I can remember just about tying bellows of the 4x5 (Calumet rail) into a knot trying to photograph. Finally I would realize what I was doing. I would zero everything out and do the minimal movement I really needed. Have fun!

Vaughn

[Chuck P.]

I guess I have to learn to spot compositions where tilts/swings would be advantagous and where I'm better off without them?

That pretty much says it, IMO.

[ImSoNegative]

I photograph in the forests quite often. It can be a fun challange to bring a little order from chaos. But swings and tilts are difficult to use because of all the blasted trees! If it were not for all the trees, photography in the forest would be a breeze!


Love It!! lol

[rdenney]

Some images need a strategy for placing the focus plane so that it makes it possible to stop down enough to get the needed depth of field. This one, for example, required a very long time for me to find the right spot, but then the camera was positioned where it was difficult for me to put my eye up to the loupe so I had to take frequent rests to keep from dripping sweat on the ground glass.

http://www.rickdenney.com/Island/loftstairssaltbox2012.jpg

The camera is pointed straight down, and I used a bit of downward lens tilt and right swing, looking for sharp focus at the middle of the top stair, the middle of the stair halfway down, and the middle of the bottom stair. But I still had to stop it down to f/45 to get the rest of it sharp. The key is that the scene presented a desired focus plane--that plane that approximately skims the stair edges. A couple of times I zeroed the movements and started over because I was working against myself.

This one is in the same room, turned around and pointed away from those stairs. No tilts would do any good here--the scene presents no single focus plane--getting the floor sharp would kill the ceiling and vice versa. But I did use just a touch of left swing to get the window frame and the pot on the table both sharp, and stopped down (to f/32) to get the rest. That move was obvious and easy--one minute.

http://www.rickdenney.com/Island/loftsaltbox2012.jpg

(pardon the magenta cast--I'm fixing this batch that was tainted by a whacked monitor profile. I just linked the image here; it will correct itself when I replace it at the source.)

The question you ask is whether there is a plane of sharp focus that would make an easier starting point to get the needed depth of field by stopping down. Often, there is no aperture small enough to get the needed depth of field without applying tilts or swings.

One might read the responses and conclude that tilts and swings are a toy for those who like to fiddle and not a useful tool outside the studio, while others might imply that movements should make it possible to never stop down more than f/16 or f/22. Neither of those assertions work across my experience.

But poles and tree trunks look wrong if they are not uniformly sharp or unsharp. So, in a forest, I would probably reject using tilts out of hand--whatever plane I would be seeking would likely still be vertical. But I would not reject using swings. I would decide which two tree trunks needed to be in the focus plane, swing to achieve that, and then stop down from there. Two parallel lines (as in, tree trunks) define a plane. Three may not fall on one plane, however.

If find it generally easier to apply too much movement as a starting point and then back off until I get the focus plane I want. That has always seemed less fiddly than working up to it and being afraid to go too far.

Rick "noting that short lenses are particularly fiddly" Denney

[Bill_1856]

One of the great advantages (and sometimes disadvantaes) in shooting LF is that when the lens is stopped 'way-down, even though you are well into the range of diffraction, prints will still appear quite sharp. Generally, if you need lots of DOF, then the best way to get it is to stop down the aperture as much as you need.
It's also necessary to point out that when "movements" are used, only a very few degrees (venerally less than 5 degrees) will do the job -- no need to reconfigure the camera like a pretzel.

[Heroique]

Vaughn, I hope you’ll allow me to name your poem “Focus in the Forest,” though you might have a better title:


Focus in the Forest
--by Vaughn

If it were not
For all the trees
Photography in the forest
Would be a breeze!

BTW, I’ve also taken the liberty of forwarding it to the Pulitzer committee for poetry.

;^)

[Vaughn]

Yeah. I'll let you know when the Pulitzer folks get a hold of me.

Sand dunes are another place where it is hard to photograph. All my prints tend to look grainy. Eureka Vally Sands Dunes (Death Valley NP) are pretty neat...a bit sandy, though.

Pretty straight forward front tilt with this one...and no trees.
Near the top of the Eureka Valley Sand Dunes
Gowland 4x5, Caltar IIN 150/5.6. TMax 100 probably, HC110
16x20 Silver Gelatin print

[Meekyman]

Thanks everyone for your contributions, especially Rick with your examples.

Cheers

Graham

[Meekyman]

Hi Folks,

Just wanted to say that after some practice at home, I returned to the same woods/forests this past weekend found focussing much easier and walked away having taken three photos! My first large format photos with my own large format camera!!

Cheers

Graham

[Chuck P.]

Congrats!

My final thought on focusing, while tilt affords the opportunity to bring near (generally shorter objects) and far (generally taller objects) elements in focus at the same time, it also limits DoF because DoF gets narrower closer to a tilted lens. So, in all cases, DoF can be maximized with an untilted lens, but never tilting the lens is not always the most efficient use of DoF (a Merklinger paraphrase). This is why I always look first to see if I can get away without using any tilt. But it has also become easier for me to recognize, rather quickly, when tilt is going to be needed, and even swings.

Keep per-severing!

[Randy]

Graham, I had posted a thread on the forum a while back, as I had some focus questions also. Take a look (http://www.largeformatphotography.info/forum/showthread.php?96075-Depth-of-field-question).

[Meekyman]

Hi Folks,

And received the processed images back.

I am even more surprised....exposures seem good (even 16 second one counted in my head with velvia 50), focus is good and I like them! OK, never, ever be good photos bearing in mind this was more of an exercise in getting used to trying to focus very three-dimensional pictures but given me confidence that my camera and secondhand holders work well. Confidence to keep on going and try to take some decent images!

I like!

Graham

[C. D. Keth]

Sand dunes are another place where it is hard to photograph. All my prints tend to look grainy.

Well quit focusing on all that sand and it won't be grainy! ;)


Graham: Glad your first outing is looking good. The only real way to get the hang of a view camera is to practice a lot. Slow down and allow yourself to think about what you're doing. Before long, the technical stuff will be pretty automatic and you'll be able to feel your way through a picture more than think through it. I wouldn't be afraid to stop far down when you need to, either. Yes, "diffraction blah, blah, blah" but a good picture ever so slightly less sharp than it could be is still a good picture.