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View Full Version : tachihara back not straight, is this normal?



bukaj
28-Sep-2013, 15:45
I just recently purchased a Tachihara 4x5 from KEH. The brackets that control sliding the back appear not to be straight. Since this is probably best explained with pictures, see the attachments below. If I start tightening the knobs after sliding the back forward, it doesn't remain parallel to the lens plane (see first photo). I can force it to be straight, but I'm worried that over time the brackets might break. One of them is already loose. You can also see in the second and third photo that the brackets themselves aren't straight with the camera.

Tachihara owners, does your camera have this problem? Is it fixable? I have contacted KEH and am awaiting a response, but want to see if there may be another solution to fix this problem.

Thanks.

lenser
28-Sep-2013, 16:24
I'm not at all certain that this is the problem, but with every tracked view camera that I have ever owned, I've accidentally run one side or the other off of it's track. More times than not, when I've put it back on, I've engaged the wrong tooth which gives the same appearance as photo 1 and results in exactly what you describe.

In my case, the solution was to repeat running it off and fiddling with the other side's position until I could match the loose side in perfect alignment and then back both of them onto the track. It may possibly be that simple.

Good luck.

Leigh
28-Sep-2013, 16:56
This is the rear "shift" feature of the camera.

You adjust each side independently, then lock the adjustment by tightening the small thumb screws on the black metal plate.
The two adjustment thumb screws are not on a common shaft because there are sliding components between them on the base.

If you have to force anything, those thumb screws are probably already tightened. You must loosen them to adjust the back.

- Leigh

Jon Shiu
28-Sep-2013, 17:03
As you suspect, it is not normal for the rear standard to get crooked when you tighten down the knobs, and forcing is not needed in a normal camera either.

Also, I usually use the back standard all the way back or all the way forward, depending on the lens focal length being used, ie 210mm or 90mm. Of course, you can position the front standard on its rail also.

Jon

lenser
28-Sep-2013, 17:08
Leigh,

I used to own a TOKO which has somewhat similar rear shift features. All of these photos seem to show the shift plates matching up in their proper zero position.

Take another look at the position of the bottom of the sliding units for the track in photo 1. A close look shows that the left one is farther down the track (one or two teeth worth) than the one on the right. That is what I based my suggestion on as it seems that the whole base of the rear standard is shifted off by those one or two teeth being out of position.

Obviously you are correct in that it can be corrected by activating the rear sift controls, but that still leaves the camera out of alignment if bukaj wants the zero positions to be accurate for a starting point.

Leigh
28-Sep-2013, 17:20
I used to own a TOKO which has somewhat similar rear shift features. All of these photos seem to show the shift plates matching up in their proper zero position.
Take another look at the position of the bottom of the sliding units for the track in photo 1. A close look shows that the left one is farther down the track (one or two teeth worth) than the one on the right. That is what I based my suggestion on as it seems that the whole base of the rear standard is shifted off by those one or two teeth being out of position.
I agree that the first photo is not square, but neither are the adjustments.
The black plate visible above the wood is definitely higher on the right side.
I think the difference between the right and left adjustments accounts totally for the angular offset of the back.

In the second photo the adjustments are equal and the back is square.

The OP mentions "forcing" the adjustments.
There is some slop in any such adjustment system. I think that's what you see in photo #1.

- Leigh

lenser
28-Sep-2013, 17:39
Leigh,

Agree on the second shot that the track adjustments seems to be perfect on each side, which I am still trying to reconcile with my theory,
but rock back and forth between one and two and you will see that in one, the right side of the camera is higher above the wood simply because the photo (one) is not take on the square as was the photo two so it's the image that is tilted out of square, not the features of the camera.

Question. On my old TOKO. the back swing was made from two matching base plates so that when it was zeroed, the edges matched, and when in an active more, they spread open on a central pivot. Not having handled a Tachihara in probably twenty years, I'm trying to remember if they used the same sort of design. The position of the tightening screws would seem to indicate that as it appears to operate on a curved slot track on the top plate as did the TOKO.

Please correct me if there was another system in operation.

Leigh
28-Sep-2013, 17:52
Agree on the second shot that the track adjustments seems to be perfect on each side, which I am still trying to reconcile with my theory,
but rock back and forth between one and two and you will see that in one, the right side of the camera is higher above the wood simply because the photo (one) is not take on the square as was the photo two so it's the image that is tilted out of square, not the features of the camera.
I think the difference in position is a correct representation of the camera geometry, not a photographic anomaly.
As such it would fully explain the problems the OP is experiencing, given that the components are being severely stressed.

His statement: "I can force it to be straight, but I'm worried that over time the brackets might break." indicate the locks are not loose.


Question. On my old TOKO. the back swing was made from two matching base plates so that when it was zeroed, the edges matched, and when in an active more, they spread open on a central pivot. Not having handled a Tachihara in probably twenty years, I'm trying to remember if they used the same sort of design. The position of the tightening screws would seem to indicate that as it appears to operate on a curved slot track on the top plate as did the TOKO.
My TOKO, which I sold a year ago, worked the same way, with the rear swing about a central pivot.

The Tachihara is different. The locking plates on each side are independent. One is attached to the base and one to the back on each side.
They are completely separate metal assemblies. No central pivot exists.

- Leigh

Jon Shiu
28-Sep-2013, 18:06
The sliders are not supposed to be independently adjusted on the 4x5, but adjusted in tandem, maintaining straightness. (The 8x10 model has a different mechanism).

Jon

Leigh
28-Sep-2013, 18:14
The camera under discussion appears to be an 8x10.

The fact that the two sides are in different positions in the first photo confirms this.

- Leigh

bukaj
28-Sep-2013, 18:21
The focus rack is completely independent of this adjustment so it's not an issue of one side being on the wrong tooth. It only moves the front standard of the camera. As is the swing for the back. The swing is centrally pivoted on the black plate you see behind the knobs.

This photo (http://www.fotofachversand.at/shop/components/com_virtuemart/shop_image/product/Tachihara_4x5_in_4b9a406dd8fcb.jpg) shows another view of the camera. The cams/switch looking things in the back are loosened to adjust the swing of the camera. The knobs below are simply for sliding the back standard back and forth. There are no teeth or gears for this movement. There is some play, but it only moves front to back with no other movement when those knobs are loosened.

This photo (http://farm4.static.flickr.com/3003/2632739642_b7830067c3.jpg) shows the camera with the rear standard slide forward. The rear bottom knobs are the only thing that needs to be loosened to move the rear standard.

I've been using a 90mm lens which requires me to move the back standard forward using this adjustment. The first photo was tightening down the two knobs and letting the back fall into place. The left bracket is sitting lower than the right side bracket. I took off the ground glass/film folder but you can see that the rear standard is not parallel with the base of the camera. This is not due to the photo not being perfectly straight on. The second photo was taken after I had to twist the back while tightening the knobs to force the back to be straight. The third is a close up of one of the brackets that guides this movement. If you look closely you can see it's not parallel to the camera itself. It seems like the brackets themselves are crooked.

I hope this is clearer than my original post. I can take some more photos if that will clear anything up.

Thanks.

bukaj
28-Sep-2013, 18:22
This is a 4x5 camera.

Leigh
28-Sep-2013, 18:31
This is a 4x5 camera.
Completely different camera from the 8x10 discussed above.

It would have helped if you had included that information originally.

- Leigh

bukaj
28-Sep-2013, 18:35
It is stated in the original post.

Leigh
28-Sep-2013, 18:46
Hmmm. Yes it is. I didn't see that when I read the post originally.

- Leigh