Wista VX with 5x7 adaptor back

[andrew gardiner]

Hi there, I am attempting to use my new 5x7 adaptor back on my Wista VX. I'm trying to make portraits with a 210 Sinaron S which supposedly has a very adequate image circle of 310mm. With all my results so far I am getting soft, black, obscured areas at the ends of the image which extend in about 5-10 mm in on both sides. Are these the bellows? Does anyone have any ideas on how I might solve this issue? ( There is a small light leak also on the left hand side which I seem to have resolved subsequently). When I shoot landscapes focussed at infinity or thereabouts the edges of the image are normal.

Best

Andrew

89279

[Vaughn]

Looks like shadows of the bellows.

Set up the camera like you did for the above image (same focusing distance)...open the lens (using the same f/stop) as you did for the portrait. No film holder. Now look thru the lens -- you should be able to see the edges and the corners of the GG without the bellows intruding into your view/line of sight.

You might need a way to pull the front of the bellows forward.

[andrew gardiner]

Thanks Vaughn, could you elaborate on your thoughts about pulling the front of the bellows forward.

Andrew

[Vaughn]

Some LF cameras have a tab on the bellows (towards the front -- often about 5 or more folds in) that has a ring on the end that can be attached to the a hook or stud that is on top of the front standard. When hooked forward, the bellows get pulled forward that number of folds.

The Crown View (brown bellows) would be an example:

http://www.largeformatphotography.info/graphic-view/

Another way around it, is to clip a fold with one of those heavy duty paper clips, like this one:

http://depositphotos.com/5780115/stock-photo-Paper-clip-or-bull-dog-clip..html

Then run a heavy duty rubber band through the 'handles' of the clip and then hook the other end of the rubber band over the front standard. The is Richard Ritter's way on his big cameras.

[andrew gardiner]

How amazing! Thanks very much for that insight Vaughn. I wish I had time to experiment - I'm off on a big trip tomorrow and slightly nervous about trying it out. Does one have to be careful damaging the bellows?

[Bill_1856]

Using the 5x7 extension back on my 4x5 Nagaoka causes shadowing on the long dimension for any lens 240mm or longer. The problem is the rear opening, not the bellows, making it a 5x6 (Paul Strand's preferred size). It's really a pain, since my favorite lens for that format is 10."

[Ed Bray]

Just for info, the Canham MQC has a small strip of velcro (soft side) on the folds about 6 folds back, it also has a small length of hook side velcro attached to the front standard, depending on how you join the two parts it gives a fair bit of flexibility.

[andrew gardiner]

Using the 5x7 extension back on my 4x5 Nagaoka causes shadowing on the long dimension for any lens 240mm or longer. The problem is the rear opening, not the bellows
Are you sure? I only ask because on my 210 the image is fine when focussed on a far object which must mean it's down to the extension of the bellows.

[Mark Tweed]

Andrew, Bill is correct in his statement about the internal dimensions of the 4X5 camera and how they restrict full illumination the 5X7 ground glass/back when employing longer lenses. Below is a discussion taken from Q-Tuan Luong's website where his addresses this very problem with a Tachihara.

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The 4x5 Tachihara as a 5x7 camera:

For $300 you can purchase an extension back which replaces the 4x5 back. This back looks like a wooden cone with a 5x7 spring back, weights 1.4 lbs and is rather bulky (more than the camera itself). Wista also makes these adaptors specifically for the backs of their DX and SP (a different model for each).
Plus: This equipment is the lightest way to get into 5x7, and one of the cheapest, apart from using B&J and so on. A B&J costs about the same price than the 5x7 back. It weights two times more. The Kodak and Corona camera don't have full movements, as well as some Deardorffs. The Wisner and Caham are nice but cost $2500. This 5x7 combination is lighter than most 4x5 cameras, including the Zone VI and the Wisner. You have also a good multi-format ability (an important thing for me, since I did not know first which format I would prefer). The switch between the 4x5 and 5x7 is almost as fast as switching between horizontal and vertical (not taking into account the readjustments). You just change the back.
Minus: The big drawback is that the internal geometry of the camera remains 4x5, thus there is a lot of limitations on the movements and long lenses that can be used. The limitations listed are not too bad for wide angle landscape photography.
When using short lenses (eg 120), the lens has to be in the camera. Therefore, there is no possibility of shifts, plus you have to use an awkward front standard configuration, plus the tilts are limited to the back. Lenses shorter than 120mm can't be focused at infinity due to the box+body+bellows+front standard not compressing to the flange focal length.
When using longer lenses, the problem is that since the extension is a cone joining the 5x7 back to a 5x5 square, to avoid vignetting by the internal elements of the camera, the lens has to lie inside the cone. This is not a problem for the large border , but definitely one for the small one. It means: no extension longer than 260mm. In particular you cannot even use a normal 300m with the 5x7 back (but a 360 telephoto works). A 300mm on the 5x7 is the equivalent of a 60mm for a 35mm camera, thus this is pretty short.
With tilts, you have to be quite careful to avoid vignetting. I have found that with the 120mm (horizontal and moderate vertical) it is OK, but with the 210mm I cannot get enough vertical tilt in vertical format. Shifts are also extremely problematic.
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I hope this is helpful.

Mark

[Bill_1856]

Are you sure? I only ask because on my 210 the image is fine when focussed on a far object which must mean it's down to the extension of the bellows.
Andrew, it's fine with a 210mm lens -- only when it gets to a 240mm does it shadow.

[Michael_qrt]

Are you sure? I only ask because on my 210 the image is fine when focussed on a far object which must mean it's down to the extension of the bellows.


It sounds like a 210mm lens will be fine at infinity but when focused to portrait distances it is not. This is to be expected as the actual extension of a 210mm lens is most likely greater than 240mm when focused to portrait distances. This then causes the back opening to shadow the edges of the 5x7 sheet with your extension back.