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View Full Version : How to Consistently, Quickly Parallel a Field Camera?



Andre Noble
31-Aug-2012, 07:27
I like to shoot architecture requiring perspective control with my Toyo Field 45 AII (http://www.bhphotovideo.com/c/product/63767-REG/Toyo_View_180_224_4x5_45AII_Metal_Field.html) because the camera is compact and transportable. But it's really not designed for the cause.

Although it's a real pain - and I still don't have a technique to insure front lens board plane and film plane are parallel - I would like to continued because buying a dedicated architecture camera is not feasible now.

Anyone who uses the Toyo Field 45 AII or similar camera have a system for assuring parallelism quickly?

PS: I have a laser alignment tool I use for enlarger, if that might be of use.

Joseph Dickerson
31-Aug-2012, 07:45
Andre,

This is a common problem, most folks that I know will carefully align the front and back or the camera and then place some indicators so that it's easy to repeat the alignment. The indicators can be small pieces of tape with alignment marks, magic marker, although your camera being black makes this a poor choice, even a couple of small dots of finger nail polish will do the job.

I that doesn't work with the Toyo, it's been many years since I owned a 45A, should never have sold it by the way, measure the top of the front stage to the rear stage when the camera is aligned and make a note of the distance. It should be consistent.

JD

Vaughn
31-Aug-2012, 08:17
I just go by the image on the GG. Seems like most of the time the landscape is not parallel to either my lens or film plane anyway.

I suppose one could just set the camera up straight on to a large blank wall, focus wide open and move the front standard until the whole wall is in focus, then mark one's rails or whatever at this 'zeroed' point.

B.S.Kumar
31-Aug-2012, 08:48
I don't know about your Toyo Field AII, but my Wista's front standard has a detent at the zero position, and of course when the back is flush against the body there is no problem aligning both planes to be parallel. I've used a number of Wista and Technika cameras over the years, and it has never been a problem. If your camera doesn't have a zero detent, you could use the laser alignment tool to mark a zero point. Also the Wista groundglass has a grid, helping to make sure everything is aligned properly.

Kumar

Peter De Smidt
31-Aug-2012, 10:15
They Toyo field cameras do have detents. You could check them with an accurate level, calipers...

lenser
31-Aug-2012, 10:38
A simple angle finder from the hardware store (in the section with levels) should do the trick easily. All you do is set the back for perfect level, then place the angle finder on that to assure 90 degrees, then go to the front stand and repeat to the same 90 degrees.

chassis
31-Aug-2012, 14:33
I have a Toyo 45AII and can confirm the following detents:

Front shift
Front swing
Front tilt
Rear tilt
Rear swing

The detents work if the camera bed is level. If the bed is tilted then you will need a method such as a measuring tape/rule to ensure alignment.

Doremus Scudder
31-Aug-2012, 17:09
You are obsessing unnecessarily. The position of the back, and only the back, is what controls rendering of parallel lines (or distorting them, if you like).

Set up your camera so that the back is leveled front-to-back and side-to-side (I do it in that order, using a level and then visual alignment with the ground glass grid). This will get your verticals straight. Then pan to get your horizontals as you wish them (assuming that the pan doesn't misalign the verticals, in which case you'll have to get them straight again), and you're good to go.

Take care of the lens stage positions when focusing, using swings and tilts to get the plane of sharp focus where you want it. No need to make sure it is parallel with the back.

I do lots of architecturals with wooden field cameras and this works just fine.


Best,

Doremus

ic-racer
31-Aug-2012, 17:54
I

PS: I have a laser alignment tool I use for enlarger, if that might be of use.

I use two methods and double check each.
1) Laser Method: you actually can use any laser pointer, you don't need a Versalab but if you have it you can use it.
a) Set camera on tripod and remove the lensboard. The camera does not need to be level or plumb, but all the movements need to be at the zero detents. Shine the laser at the film back. Horseman has a shiny side of the fresnel there so it bounces the light back and make note where in your room the laser beam is shining. (other cameras require a piece of optical glass at the film plane; did your Versalab come with a 4x5" optical glass for this purpose?). You can move the camera around on the tripod so the beam shines back at a convenient place (it does not have to point exactly back at the Versalab center unless you want it to).
b) Now mount the lens with a microscope slide on the front rim of the lens. Zero the detents so the beam bounces off the microscope slide and shines to the same place as before. Double and triple check, mounting and un-mounting the lensboard, etc. until happy.
2) Optical test for wide angle lenses: Put a pice of tape on your focus knob. Focus an object on the horizon at the far right of the ground glass with a high power loupe (this will be very challenging with some cameras and some loupes and very wide lenses but the wider the lens you can use, the better you can set the detent). Note exactly where the focus knob is. Swing the camera on axis until the same object is now on the far left of the ground glass. Re-focus on the object. Now check the focus knob to see if it is back in the same place. Repeat as needed to get a good idea if the front lens swing detent is indeed correct. If not re-adjust it. Keep notes of which way you swung the detent because it is a little non-intuitive to know which way the detent needs to be swung to rectify the focus being a little too far in or out on one side.

Anyone that needs to know where the detent adjustments are on a Horseman FA, let me know.

PS: I would not use a lens 90mm or greater on a 4x5 camera without detents. 8x10 cameras are different. Even with a low power loupe or no loupe you can tell if the front is not centered as your are composing in the field. Though, when I get my 75mm Hypergon for 8x10 (ha, ha, ha!), I may report back that it is impossible to use on my present 8x10 camera with no front detents :)

Mark Barendt
31-Aug-2012, 18:13
You are obsessing unnecessarily. The position of the back, and only the back, is what controls rendering of parallel lines (or distorting them, if you like).

Set up your camera so that the back is leveled front-to-back and side-to-side (I do it in that order, using a level and then visual alignment with the ground glass grid). This will get your verticals straight. Then pan to get your horizontals as you wish them (assuming that the pan doesn't misalign the verticals, in which case you'll have to get them straight again), and you're good to go.

Take care of the lens stage positions when focusing, using swings and tilts to get the plane of sharp focus where you want it. No need to make sure it is parallel with the back.

I do lots of architecturals with wooden field cameras and this works just fine.


Best,

Doremus

+1

Andre Noble
31-Aug-2012, 19:30
A lot of good ideas here. Thank you everyone for taking the time. I will check my Toyo to see if it has adjustable zero detents for front lens stage tilt. Ive had this camera for 13 years and I don't know :) If yes, will try out ic-racer's ingenious suggestion.

thanks again everyone for taking the time. Andre

John Kasaian
31-Aug-2012, 19:43
Just remember what its supposed to look like:)

Mark Barendt
31-Aug-2012, 19:45
Andre,

Are you trying to solve a focusing problem or to square the lines on the film or ?

Andre Noble
31-Aug-2012, 23:25
I'm trying to shoot architecture requiring perspective control efficiently. That extra time for "focus near tilt far" can be a drag not to mention unsafe in urban areas (police security criminals)

Andre Noble
31-Aug-2012, 23:28
Just remember what its supposed to look like:)

The camera or the detent? :)

Mark Barendt
1-Sep-2012, 05:40
I'm trying to shoot architecture requiring perspective control efficiently. That extra time for "focus near tilt far" can be a drag not to mention unsafe in urban areas (police security criminals)

The point that I think Doremus and I know I'm making is that getting the lens board perfectly parallel with the film plane may not be (in fact probably isn't) that important for normal architectural work.

When the Toyo 45A opens up and the standards are swung up to their stops and locked, the front and rear standards are parallel. No extra work required.

Attach the lens, point at the subject, level the camera, focus, insert the film, and shoot.

All the verticals should be vertical without any convergence.

Front rise and fall is just a matter of using the slider in the front standard, everything remains parallel, no change in the verticals or even focus.

Swinging just the rear standard of the camera adjusts the horizontals on the film but does not change the focus at the center of the film. The edges right and left though will fall out of focus.

You could at this point simply stop down and shoot, using aperture to bring the entire scene back into a range of acceptable focus.

Here's the important points.

Swinging the front standard/lens-board left or right to match the rear does not affect the geometry of what the film sees and even the focus in the center should remain darn close, swing is simply a focus refinement that swings the plane of sharp focus in the scene one way or another and allows you to focus on a certain plane within the scene at a larger aperture but that comes with the corresponding shorter deth of field.

Unless the subject is flat and the only thing you want in focus is that flat surface, say the facade of a building and you want the walls behind the facade and the street in front of the facade out of focus, swinging the lens isn't critical because you will have to stop the aperture down anyway.

Most architectural shots require deep depth of field so front swing to perfect parrallel isn't normally a concern.

Even if you do need a fairly short DOF eyeballing the front swing is probably going to work very well.

John Kasaian
1-Sep-2012, 07:03
The camera or the detent? :)

The camera. You probably already know what your camera looks like when squared---make it look like that each time you open her up. Visible detents, if you will. Learn to trust your eyes.

Brian Ellis
1-Sep-2012, 07:15
I'm trying to shoot architecture requiring perspective control efficiently. That extra time for "focus near tilt far" can be a drag not to mention unsafe in urban areas (police security criminals)

You control perspective by the camera position.

Mark Barendt
1-Sep-2012, 07:24
You control perspective by the camera position.

I have a feeling that Andre is actually talking about squaring up the lines in the composition rather than the view/perspective from a given point.

Bob Salomon
1-Sep-2012, 07:35
1: Buy a very good, small level that can fit flat on your lens board.
2: Set up your camera where desired.
3: Set the level against your ground glass and adjust the back till the bubble is centered.
4: Set the level against your lens board and adjust the front standard till the bubble is centered

Your lens is now parallel to your back.

But this will not gusrantee that the building is level to the camera.

Brian Ellis
1-Sep-2012, 08:14
I have a feeling that Andre is actually talking about squaring up the lines in the composition rather than the view/perspective from a given point.

That's what he said in the original post. But then he talked about "perspective" and having too little time to "focus near tilt far." So I really don't know what he's talking about. It just seemed like a good idea to point out how one controls perspective, as opposed to controlling the plane of focus.

Andre Noble
1-Sep-2012, 08:35
Low and behold - there ARE adjustable detents on the Toyo 45AII!

PS Brian, and Bob. Yeah spirit level in order to parallel film plane to vertical - check.
Now with my front lens board already pre-parralled to rear GG - and hence also to vertical (with aid of fine tuning zero detent before hand), then I know I only need to raise front lens board per building height, focus, expose, done, close and run.

I haven't shot architecture since I was in Long Beach this winter and some dude (yes dude) complimented my rear end when I was focusing on the GG under dark cloth. :confused: Downtown Long Beach.

C. D. Keth
1-Sep-2012, 15:01
... and some dude (yes dude) complimented my rear end when I was focusing on the GG under dark cloth. :confused: Downtown Long Beach.

Your last long beach experience was better than mine. The last time I was down there somebody threw a glass bottle at me while I was under the dark cloth.

Drew Bedo
3-Sep-2012, 19:48
I have used a small (6") T-Square on my 4x5 Zone VI.