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yuexiachou29
22-Mar-2015, 20:30
I've had problem in focusing three subjects that are not on the same focal plane.
Like the drawing below, person 1,2,3 are lined up in 2 rows. I can't get 3 subjects in focus on one image.
If I want to have deeper DOF, I can change the f stop, but in reality it doesn't like that.
131304
What kind of camera movement should I do in order to make these 3 subjects all in focus?

thank you.

My large format camera bible is not with me, otherwise I'd look it up.

thanks.

Michael Clark
22-Mar-2015, 20:41
I assume these people are standing up vertical, you picture has them lying down (horizontal). If persons 2&3 are at the same distance from the camera and person #1 closer and is between the other two there is no movement that can bring them all in the same focus plan. Only using a smaller f stop to increase depth of flied can you get every one in focus.

yuexiachou29
22-Mar-2015, 20:46
"using a smaller f stop"
I tested it out with digital camera and it doesn't seem work out well.
in your experience, how well does using smaller aperture play?

OR i could take 2-3 shots and make sure everybody is covered.
then compose these images together in post?

Michael Clark
22-Mar-2015, 21:04
When I say smaller f stop it means the aperture closes to a smaller opening, which will increase your depth of focus, allowing hopefully all three people to be in focus. All so the sorter the focal length of the lens the more depth of field it will have. Finding a book on basic view camera use would make it more clear than I can explain here.

Michael Clark
22-Mar-2015, 21:24
Sorry yuexiachou, reading your post it seems to me you know what depth of flied is, but with this arrangement of people I would depend on using the smaller F stop to get good focus . I know very little about digital cameras.

vinny
23-Mar-2015, 05:07
Based on your posts, you might want to read the articles here on using a view camera as well as watching some youtube videos. This is very basic stuff that may be hard to comprehend w/o someone demonstrating it.

ic-racer
23-Mar-2015, 06:30
http://www.largeformatphotography.info/how-to-focus.html

Lenny Eiger
23-Mar-2015, 09:00
Smaller apertures work very well in large format cameras. It is very different from digital cameras.

My lenses do excellent work all the way to f45. Most digital camera lenses are optimized for the low end and have a fair amount of diffraction going on and you go up the scale... You shouldn't compare them.

Lenny

tgtaylor
23-Mar-2015, 09:45
If your camera is center tilt, then focus on the near (1) and tilt for 2 & 3 - if they are in rows, then the row is equidistant from the lens. That said 3 may be further out than 2 in which case you would stop down for 2. If your camera is base tit, then it would be the opposite of above.

Thomas

Peter Lewin
23-Mar-2015, 10:52
If your camera is center tilt, then focus on the near (1) and tilt for 2 & 3 - if they are in rows, then the row is equidistant from the lens. That said 3 may be further out than 2 in which case you would stop down for 2. If your camera is base tit, then it would be the opposite of above.
Thomas
To add a small proviso to Thomas's suggestion: By using tilt to get the three faces into focus, the focus plane is no longer perpendicular, it is angled, so while the faces may be in focus, the individual's feet or lower torsos will probably be out of focus. No matter how you position the focus plane, you need to shut down (i.e. choose a higher-numbered f-stop) to gain depth-of-field.

tgtaylor
23-Mar-2015, 21:12
Peter is right about stepping down. In practice I always focus at the widest aperture and then step down to the taking aperture. It's a good idea to look thru the GG when stepping down to make that determination rather than just stepping down to some pre-determined aperture without looking.

Thomas

tgtaylor
23-Mar-2015, 21:28
When posting earlier this morning I was thinking that maybe a slight swing would be in order if, say, 3 was further out on the row than 2 even thou the distance to the row line would be equal. But since I wasn't behind the camera I discounted that for purposes of brevity. So, maybe, and I stress maybe, a tad of swing would be more appropriate. What do you think?

Thomas

Doremus Scudder
24-Mar-2015, 00:53
You guys are just confusing the issue here.

In the scenario posited by the OP, there are no camera movements that will get all three subjects in the same plane. Depth-of-field is the only help here.

In essence, there are two planes in the scene that would both need to be in focus. Movements allow one to position one plane-of-sharp-focus, but not two. One could get two of the three people in the same plane, but never all three (unless you were shooting from directly above, in which case you could get the tops of all the heads in the same plane; I don't think that's what the OP is after here though...). So stopping down is the only available tool.

That said, the placement of the plane of sharp focus in order to take best advantage of depth-of-field is crucial. In this case, it should be parallel to the plane of the two people in the back row and halfway between the near person and the two people in the second row (hope that's clear...).

Further, to clarify "halfway"; the thing to do is focus on the far plane, note the position of the standards, then focus on the near, note the position of the standards and then split the difference by positioning the standards at the midpoint between the two distances. The amount of focus spread will determine the optimum f-stop. To find the best f-stop, you need to have tested a lot or read the following: http://www.largeformatphotography.info/fstop.html

Best of luck to the OP,

Doremus

Tobias Key
24-Mar-2015, 02:00
All you could do is stop down, or rearrange the group so swing is possible. In other words have them moving further away from left to right or have one close on the left and two further away on the right. Having one subject close and in the centre scuppers all opportunity for movements.

tgtaylor
24-Mar-2015, 09:39
Here's a somewhat similar situation:

http://spiritsofsilver.com/yahoo_site_admin/assets/images/Mission-Church.58223427_large.jpg

IIRC I used front tilt and stopped down so that the cross in the foreground (1), trees in the mid-ground, and church with bell towers (2&3) were sharp throughout. This is a salt print to the actual print is not as sharp as it would had I printed it as a SG on glossy paper.

Thomas

tgtaylor
24-Mar-2015, 09:46
Here's another one:

http://spiritsofsilver.com/yahoo_site_admin/assets/images/Windjammer.58224111_large.jpg

As you can see, everything in this image is sharp from the foredeck and mast in the foreground, the rigging along the port and starboard sides, to the rear deck entryway along with the rear deck. Again, tilt and stopping down worked.

Thomas

Heroique
24-Mar-2015, 10:06
...rearrange the group...

I'd ask the front person to take a couple steps back.

Or the two back people to take a couple steps forward.

As you give these instructions, say you want to make sure everyone looks handsome.

Doremus Scudder
25-Mar-2015, 03:22
Thomas,

Nice photographs! I especially like the square-rigger.

As to your use of tilt for such subjects: Yes! A lot of people would just stop down in such a situation, but given that there is a lot of foreground in front of the mast that you want to keep sharp, a small amount of tilt places the plane-of-sharp-focus in an optimum position to get the most out of depth-of-field.

I don't think this was the OPs situation, but it points out a very important aspect of using camera movements; that of getting the plane-of-sharp-focus at a minimum distance from all the elements in a scene that you want to render sharply. The check for me is always focus spread. I tilt or swing to place the plane-of-sharp-focus at what I believe to be the optimum location (by choosing focus points in the scene to focus on) and then check by using focus spread. The amount of movement that gives the least focus spread between "near" and "far" elements in a scene is always the best.

Again, great prints!

Doremus

tgtaylor
25-Mar-2015, 15:08
Thanks Doremus .

When I first got into LF, setting-up a plane of focus was confusing for me. For me 3 points determine a plane and I don't believe that the author of the LF intro book that I bought by Stone or Stewart differentiated between base and center tilt cameras. I remember trying the hyerfocal method that I used so successfully with a Pentax MF camera but it didn't pan out for that shot and haven't tried it since with LF. Nowadays focusing on the near and far and stopping down for everything else has been the answer for me so far.

Thomas