How do you correct verticals

Following on the previous post on verticals...

I took my super speed graphic out this weekend for my first foray into correcting verticals on an old building downtown. As it turned out I couldn't fit the whole building in my frame (but that is another story). As this was my first real attempt to play with the rising front on this camera, it was interesting. I had a hard time deciding if all the verticals in the shot were in fact vertical if one was. I.e. I line up the closest corner of the building on the edge of my ground glass since I don't have any grid or anything else to use. Then I panned around to check the other verticals. They looked vertical when they were on the edge but not necessarily when they weren't. This was probably a trick of the eye.

What method do others use to align verticals? I can't imagine that there would be anything wrong with using the edge of the frame, but then again these LF cameras never cease to amaze me at how complicated they can be for such a simple idea! Thanks.

One thing that you know is that a building is straight and plumb. If you adjust your GG using a bubble level to make sure that it is the same, then it will be parallel to the face of the building and your verticals should be correct. Then use the rise and falls to compose.

Are you sure your tripod was perfectly level? If it wasn't, panning will introduce tilt, which would cause the effect you were seeing on the ground glass. I know that my old tripod head has a bubble level on the bottom of the head which made it easy to level the tripod.

If you shoot old structures, you can't actually always count on them being straight and plumb.

I've drawn gridlines on my groundglass so I don't have to rely on the edge of the frame.

Make sure the tripod is level, so that if you pan with the head in the neutral position (you may also want to mark the neutral positions on your tripod head and camera for quicker setup), the camera stays level. I start with the camera level, checking the rail (if I'm using a monorail camera) and the front and rear standards along both axes.

I try to correct first with front rise (or rear fall, if you have it). This produces a more natural result than with rear tilt alone, which only corrects verticals in one plane, like tilting the enlarging easel or using PhotoShop's "perspective correction" tool. If I run out of front rise and still have more image circle, I might add some indirect front rise if necessary by tilting the camera up and applying front and rear forward tilt in parallel to compensate.

If you get your lens board and film plane parallel with the surface of the building, then you're doing about as well as you can. A bubble level is very useful in this, although you can eyeball it pretty well if there are parallel lines on your ground glass. And then, if you print the shot, you can fiddle a little more under the enlarger if needed.

Level

KenM said:

Are you sure your tripod was perfectly level? If it wasn't, panning will introduce tilt, which would cause the effect you were seeing on the ground glass. I know that my old tripod head has a bubble level on the bottom of the head which made it easy to level the tripod.

Click to expand...

I think the light just went on. I did not make sure my tripod was perfectly level, and being that it was a sidewalk, this is probably what I was seeing. One more reminder to myself to slow down!! Thanks.