Attaching a mm scale to a wood field camera

**Dan Jolicoeur** · 19-Apr-2006, 18:01

Again; A $20 digital caliper from harbour freight. I chopped off the jaws, but not necessary for this application. You can use it from behind the camera as a depth gauge. Focus on the near press zero. Focus on the far, reposition half the distance, and select your f stop from the focus spread. It is not over kill, it is fast accurate, and indispensable once you get use to using it. With the jaws off it fits anywhere in you pack and weight is little. It can be used mounted to the side or hand held from the front or from the rear.
Give it a try,

**Brian Ellis** · 19-Apr-2006, 18:01

Ralph Barker said: "Ideally, the 0 point on the attached scale would stay constant in relation to the film plane within the back standard, so a direct measurement from the position of the front standard could be taken."

Ed should perhaps tell us why he wants to put the scale on his camera. I assumed the reason he was doing it is that he wanted to use it as an aid in focusing and in determining the optimum aperture, i.e. to focus on the near, look at the mm scale, focus on the far, look at the mm scale, position whichever standard you're using midway between the two positions, etc. etc. (a common method discussed in greater detail in Tuan's article on this site about focusing the view camera). If that's the purpose there's no need to start at a zero point because all you're interested in is the difference in mms between the near and far focusing positions. The actual numbers don't matter , i.e. it doesn't make any difference whether you start at 0 or 10 or 85 or any other number, all you care about is how many mms there are between the two focusing positions and where the midpoint between them lies.

**David Karp** · 19-Apr-2006, 18:09

I use a mm scale for the reason Brian describes. I made one for my Crown Graphic and for the back focus on my Walker Titan SF by printing a mm scale that I found on the Internet and laminating it using Avery self adhesive laminating sheets. I attached this to the camera using double sided carpet tape. Works great so long as there is space on the camera and a reference point available for measuring the movement when you focus from far to near. I keep the f/stops that correspond to the various distances on a laminated note card that I can print out from my computer. I keep a couple in my backpack in case I lose one. It would also be possible to stick this information to your lensboards so that it is always available.

**Ed Pierce** · 20-Apr-2006, 07:21

Thanks all for your helpful responses.

Brian, you are correct in that I'm looking to use the scale for determining optimum focus point and aperture.

Ralph, thanks so much for your insightful comment. It makes a lot of sense to attach the scale to the rear focusing rail with the zero point under the film plane, and mark a reference point on the front focusing rail. That way I can always get a direct reading of bellows extension if I want it. Now why didn't I think of that??? Of course, any tilts will throw off a direct reading but it will still work for my main purpose.

I'm hesitant to tape or glue anything to the camera as it does get wet. Ideally I'd like to find a metal scale and attach it with screws. Any ideas on this?

For bellows extension factor, I have a cloth tape which I've marked up with the required changes in exposure for my various lenses. One side of the tape is for the 4x5 and the other is for the 8x10. To use it I just hold it up from the film plane to the front standard- works well.

**Andy Jones** · 21-Apr-2006, 21:25

I made something like you are describing when I got started in LF . I don't always use it, only in "limit" situations. It has distance scales for the three lenses I have as well as hyperfocal distances at several apertures. My main use, as others suggest, is focus spread readings and sometimes bellows extension (My notebook has the tables for factors)

This will take you to a pic - it is on an Ebon45S.. http://www.fototime.com/185EE92499CA845/orig.jpg

**Andy Jones** · 21-Apr-2006, 21:30

Ed, This ruler just slides under and between the standards as necessary but slips out when not needed and goes in the bag, it's not much longer than the QuickLoad back. Obviously it would be too long to attach permanently but the bent up end makes it easy to positively align with the film plane. (In case you were wondering, yes I still use the loupe to confirm focus and don't rely on this :-) )