DOF calculator for a Chamonix

[bomzi]

I recently purchased a Chamonix 045N2. This is my second 4x5, the first being a lovely Sinar F2. The Chamonix is fantastic (my shoulders and back are rejoicing!) but I am missing the Sinar's extremely helpful DOF Calculator (also missing the swing and tilt but I tend to use that less).

I looked through this thread on how to make one for the Chamonix but I don't like the idea of attaching a plastic film can to the camera:
http://www.largeformatphotography.in...-045n1-cameras

How are other Chamonix users dealing with this?

Also, would the method indicated in the thread above work as a flat card? So you focus to the far point, place the card with the DOF markings on something that doesn't move, then focus on the near point and read off the number?

I hope this makes sense. I'm also considering buying a Rodenstock DOF calculator.

[vinny]

Magnetic strips they sell in a roll. Or rare earth magnets. Both stick to the stainless steel rail.

[Preston]

"(also missing the swing and tilt but I tend to use that less)."

Changing the subject just for a moment, but to which swing and tilt are you referring to?

I have an 045N-2. It has front swing and tilt (and shift), and rear swing and tilt. If you're referring to tilting the back toward you, there are two slide locks at the bottom of the back, one on each side. If you slide those inboard, you can tilt the back toward you. Similarly, there are locks at the bottom of the front standard. Slide those inboard and you can tilt the lens.

--P

[ic-racer]

I recently purchased a Chamonix 045N2. This is my second 4x5, the first being a lovely Sinar F2. The Chamonix is fantastic (my shoulders and back are rejoicing!) but I am missing the Sinar's extremely helpful DOF Calculator (also missing the swing and tilt but I tend to use that less).

I looked through this thread on how to make one for the Chamonix but I don't like the idea of attaching a plastic film can to the camera:
http://www.largeformatphotography.in...-045n1-cameras

How are other Chamonix users dealing with this?

Also, would the method indicated in the thread above work as a flat card? So you focus to the far point, place the card with the DOF markings on something that doesn't move, then focus on the near point and read off the number?

I hope this makes sense. I'm also considering buying a Rodenstock DOF calculator.

I just have a single mark on the knob and eyeball it. One hour = f8, three hours = f32, etc. If you want to use a 'flat card' scale you can mount it on the focusing rail (maybe with a magnet or velcro, so you can move it to zero it).

[C. D. Keth]

I don't. I use the ground glass to tell me what is and isn't in focus.

[bomzi]

Yeah these magnets sound like a great idea. I guess I'll have to adapt the circular DOF scale to a flat card first.

[TXFZ1]

Yeah these magnets sound like a great idea. I guess I'll have to adapt the circular DOF scale to a flat card first.

The DOF article on the front page has a flat card scale for 4x5, 5x7, 8x10, 11x14.

David

[dave_whatever]

The problem with a flat card on the bed is for wide lenses the difference in extension you're trying to measure is very small and hence doing it that way can be very imprescise, its much better on the focus knob for wide lenses.

On my 045F1 I've attached a scale to the back edge of the carbon base board by the knob but its not ideal. I need to come up with a better solution really.

To whoever said just use the ground glass; nice idea but in my experience if you,re stopping down to f/22-45 area in low loght, even with a maxwell screen its pretty hard to determine the point at which acceptable sharpness/focus is reached. Much easier and more reliable to use a DOF scale. The first time I added one to a large format camera was a revelation to me, suddenly I no longer had to just guess what aperture to use having focussed and applied tilt etc.

There's also the issue that what might appear to be acceptable focus on the glass through whatever loupe you carry in the field could easily then not be acceptable when scanned or enlarged to a large print size later on. Whereas, a DOF scale can be calculated to balance max sharpness and losses due to diffraction and be a max sharpness to aim for to cover you for big prints later (see the kenrockwell dof scale article, probably the only valuable thing on his site).

[Eric Woodbury]

I'm with ic-racer. The pitch on my Chamonix is 10mm/360 degrees. I have the DOF numbers on a tiny piece of paper taped to the side of my camera. 0.7mm spread is f/16, 1.3mm is f/22, etc.; doubling ever stop. It would be easy for Chamonix to add this feature with, as a minimum, markings on the focus knob. --EW--

[StoneNYC]

I don't. I use the ground glass to tell me what is and isn't in focus.

Agreed.

To be honest I don't understand how this works... Wouldn't you need a different scale for each lens? I've just never found these useful, even shooting smaller formats I never used the scale on the lens, I mean unless you're actually going out and using a ruler to measure, you're still estimating anyway...

I also don't have trouble using the GG at f/22 or f/45, in fact I was just outside in the dark at night and focussing and checking depth at f/32, just use the loupe and I can still make out what's clear from the light off the snow from the white mini-lights. 2 minute exposure kind of light.

Unless you're doing product, and then why would you be using a field camera anyway...