4x5 focus?

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I set it up for the first time last night the Cambo 45NX with a 150mm rodenstock lens. I was in my basement and picked a subject about 15 feet away to focus on, this is where I get confused. I could not focus on the item?? I moved the camera closer to this object and then I could focus, but at longer distance, I could not get the camera to focus. It seems the standards could not get close enough together to focus, I even remove the tripod collar to a different position so I could get the standards almost touching but still no luck??

Am I right in assuming the standards come closer together to focus on farther away objects?

I'm sure I'm missing something here? Can anyone help me out? > >Joe

-- Joe Tasse (jst@tassestudios.com), January 18, 2001


Joe, at 15 ft, you only need 155mm of bellows draw, you should have no problems focussing...it could be lack of light? Yes, the standards require greater seperation as objects get closer, at infinity an 150mm lens will use 150mm of bellows draw.

-- Bill Glickman (bglick@pclv.com), January 18, 2001.

Your logic is sound, focusing at infinity brings the standards closer together for a given focal length. Anything closer requires greater draw.

Squash the standards as close together as the focusing rail will allow with the tripod block removed and all movements centered or "zeroed" out and measure. If the distance from the ground glass to the lensboard cut-out (measure with the ruler or yardstick in the camera, centered on the ground glass) is much greater than 150mm than you will have to get a bag bellows or recessed lensboard. That or something is amiss.

150/165 mm is "normal" for 4 X 5 and I'd have thought the Calumet 45NX would focus a normal lens at 15 feet without having to switch to the bag bellows. However it does have a 21" bellows according to their on-line catalog. They list the minimum extension as 1 &7/8ths, but that must certainly be for the bag bellows. Even so, it suggests that with the tripod block out from between the standards you have plenty of room to bring the standards together.

Is it possible that the standards have been switched somehow? i.e. with a modular design that can be taken apart almost completely, could a previous owner/user accidentally put things back in such a way that it is functional but not correct? You bought it used? Is it complete? Try calling Calumet at 1-800-Calumet

Otherwise, are you sure the lens is mounted properly to the lensboard? Try taking the camera and lens to to a window or outside if it's warm enough and focus on a distant light source or tree branch.

-- Sean yates (yatescats@yahoo.com), January 18, 2001.

Joe, Both of the standards on that camera should be on the rail so that the rods that stick up are behind the center pivot point. You may have the front one backwards. The knob that allows "swings" will allow that front standard to swing 180 degrees so that the rods would be forward also. Is your tripod mount the one with 2 knobs. Those are long and only used with 8x10 cameras normally. You shouldn't have any trouble with a normal bellows focusing a 150. 90's get tight and you'll start wishing for a bag bellows. You'll be able to make tack sharp pictures with your combo. Hope this helps. Jim

-- Jim Galli (jimgalli@sierra.net), January 18, 2001.

WOW, I feel silly. The front standard was on backwards! Thanks for all the help guys


-- Joe Tasse (jst@tassestudios.com), January 18, 2001.

It's a very easy mistake on that camera. The modular design of the cambo is a true wonder - it is configurable in all sorts of ways. Nice camera.

-- Erik Ryberg (ryberg@seanet.com), January 18, 2001.

Try putting a small light source the same distance from your camera and see if you can bring it into focus. Basements can be pretty dim places. I'm wondering if the possibly small amount of light available in your basement makes it difficult to discern the edges on which sharp focus normally depends. Do you have problems focusing on objects at the same distance outside, where there's more light?

-- neil poulsen (neil.fg@att.net), January 19, 2001.

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