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Graybeard
31-Aug-2012, 15:46
I have a pretty Korona 5x7. The overall cosmetics are very good (no exaggeration); it has what appears to be a new bellows; and I have the rear extension track with a stamped number that matches the numbers stamped on other parts of the camera. I estimate that it is a fairly late model as it has front swings, tilts, shifts, and the hardware which secures the lensboard is the later type. As I mentioned, pretty nice and a pleasant camera to use.

When locked down, there is about 1mm of wobble at the top of the front frame; I'd prefer that the lash wasn't present but I can work around it. The rear frame must wobble about 4mm when the advance knobs are locked down; I find this excessive. I don't see any means to remove that lash from the mechanicals. The play seems to be in the guide slot on the side of the rack.

My present solution is to use a softwood wedge between the rear frame and the track to secure everything once I've found the working position for the rear frame. Not an elegant solution, but it does work and the wedges are pretty inexpensive.

My questions are:

Do other Gundlach owners face a similar problem?

If you have similar wobble in the rear frame how are you dealing with it?

Is there an adjustment or mechanical solution that I'm missing?

Thanks in advance; all comments are welcome.

BradS
31-Aug-2012, 15:51
I had a lovely 5x7 Korona some years ago. It was much like what you describe - pretty but wobbly. I believe they're just that way.

sully75
31-Aug-2012, 18:15
I have a similar Kodak camera and it does not lock down very well. I use it because it's big and wooden and people love it, since I try to do portraits of strangers, they react well to it.

But as far as locking down, I'd have to go with a monorail camera. The focusing knob is terrible and I wonder if the focusing gear is hand made. It's not precise at all.

CP Goerz
31-Aug-2012, 18:31
If you go to film holders.com Alan makes a stabilizer kit, Eddy Weston used a similar set up which you can see him with in some pics. Essentially its a rod that attaches to the front and rear standards holding them stiff and in a fixed position so there's no wiggle.

Ron Stowell
31-Aug-2012, 19:03
I also owned a beautiful Korona 5x7 that didn't get used much because of the wobble.
I now have an Ansco 5x7 that is very secure.

Peter Gomena
31-Aug-2012, 21:54
My Korona 8x10 was really loose, especially the rear standard. The hardware seemed a bit flimsy for the job. It was a good "starter" camera, good enough to convince me 8x10 was overkill for anything I wanted to do with a view camera.

Peter Gomena

Steven Tribe
1-Sep-2012, 05:21
The system - rod(s) and locking fixtures front and rear standards - pre-dates Weston.
I enclose a photo of a tailboard reisekamera (18x24cm/ 1900) which has the fitments on both sides.
It is, of course, much easier engineering when the front and rear standards have exactly the same size. The locking fixtures turn to allow adjustment.
Works very effectively in the field.

Peter Gomena
1-Sep-2012, 12:07
Hmm, Steven's post reminds me there is somebody who sells a modern equivalent rod stabilizing kit. I can't find it in my browser's bookmarks, but he's out there.

Peter Gomena

John Koehrer
1-Sep-2012, 12:54
see pst #4. :)

TheDeardorffGuy
1-Sep-2012, 14:36
A mm? You're kidding! really a mm? I metal camera might go 3mm. Leave it alone. Take some pics. Say a box of film. see if you can tell.

C. D. Keth
1-Sep-2012, 14:45
Works very effectively in the field.

Until you need a little bit of swing.

Graybeard
1-Sep-2012, 14:58
Thank you all for the replies.

My practice of a wedge under the rear frame would seem to be the best for me.

The rods that were mentioned wouldn't be a solution on my camera as the thing to which one would fasten the rod, the front standard, also has some wobble. If the two frames were joined by the rod(s) the would move in unison (admittedly only to the extent allowed by the frame with the least lash).



I also owned a beautiful Korona 5x7 that didn't get used much because of the wobble.
I now have an Ansco 5x7 that is very secure.

I have an 5x7 Ansco as well and my experience with it is the same as yours. With everything locked down tightly, the Ansco is quite rigid.

Steven Tribe
2-Sep-2012, 01:53
"Until you need a little bit of swing."

Not with a tailboard camera!

"If the two frames were joined by the rod(s) the would move in unison (admittedly only to the extent allowed by the frame with the least lash)."

Again, a tailboard camera has the rigid front standard. It is also not a question of the weakest link determining absolute stability as the locked front standard/rods/rear standard will reduce the underneath flexibility of the standards with the base.

Graybeard
2-Sep-2012, 05:02
My camera, the one with the wobble, doesn't have a fixed (rigid) front standard. One can focus with either the front or rear frames and both frames swing.

Steve Hamley
3-Sep-2012, 18:17
Wind stabilizer from Alan Brubaker

http://www.filmholders.com/wskit.html

Also try the View Camera Store to see if they have them in stock.

BUT, 1mm? Really? My 8x20 Korona is far worse, and you'd swear the thing could never take a sharp image, yet it does so time and time again. Try it as-is and look at your negs closely, you may well not need to do anything. BTW, I've always felt some cameras were too rigid and vibrated like a tuning fork with big shutters.

Cheers, Steve

John Kasaian
3-Sep-2012, 18:41
"If itsa gonna fly, itsa gotta be flexible."
---Leonardo da Vinci

lab black
3-Sep-2012, 18:43
Alan's kit is extremely functional, as previously mentioned. His typical stabilizer bar fits in bushings in the top of the front and rear standards. He recently designed an additional lateral kit for my ULF that goes from the bottom of the rear standard to the top of the front standard. In concert with his standard kit, the additional stabilizer is a welcome addition that I highly recommend.

unixrevolution
4-Sep-2012, 10:25
I am a newly minted 8x10 owner, and my Korona 8x10 wobbles just a tiny bit, but that's because the runners that go in the rail slot were loose and badly misaligned. Bending one back into shape and tightening the screws fixed it. I have since used teflon lube on all the parts of the camera that slide against each other and she's smooth as butter and quite tight now.

Harold_4074
4-Sep-2012, 11:39
I'm not familiar with the Korona, but I would imagine that it is like a Kodak 2D: the rail clamps are brass that has been bent to form tabs that run in grooves in the wood. The clamping action is crosswise, so there is nothing to lodge the tabs on an upper or lower surface of the rail or groove. Because of the short span of the clamps and the height of the front standards, it takes very little play in the grooves to permit a considerable movement at the top of the standard. On the other hand, too little play and wood expansion due to humidity can bind up the system.

A trick that sometimes works in situations like this is to use a narrow strip of shim stock, wrapped around, glued, or soldered onto the brass tab. A good automotive supply store (or, better, McMaster-Carr) will supply brass in incremental thicknesses starting at 0.001 inches. It can be cut with ordinary scissors, and trial and error may let you find a good compromise between lack of play and free sliding. One advantage of this fix is that, carefully done, it is reversible without damage to the camera.

I hope that you don't find the grooves to be tapered, so that a good fit in some places causes binding in others!

Steven Tribe
4-Sep-2012, 12:51
Now that is a very good idea. I even have a whole box of formed flat bronze (not brass) spacing pieces made for oversizing bearing shells in crankshafts which can be cut to the right size! The system would work on tailboards where the rear standard tabs run in an outside groove in the geared track.

Whilst the central rod system from Alan looks very useful (alumininium rods are stiffer than brass - and weigh a good deal less than bronze) I couldn't help smiling at the following:

"The Wind Stabilizer Kit was invented a few years ago..."

Should be:

"Wind Stabilizers have been a proven accessorary for users of large format cameras for over a hundred years. Now available in lightweight aluminium."