Recommandations for a 6x17 roll film back for 5x7 camera

[Ginette]

Hello,

It is my intention to try a 617 roll film back on my ShenHao HZX57-IIA with a graflok back.

Can I have some advices from members who uses thoses backs:
-ShenHao SPC617 Roll Film Back https://www.badgergraphic.com/store/cart.php?m=product_detail&p=3711 (6x17 only)
-Dayi 617 Film Holder for 5X7 camera http://www.bhcamera.us/dayi617back-57camera.php or on ebay http://www.ebay.com/itm/270862787997 (with 6x14 and 6x12 masks)
Both are 600$, are they worth this price?
-I know about the Canham 6x17 Motorised Roll Film Back but it price is 2x the cheapest ones.
I suppose that thoses 3 backs will fit on the ShenHao. Feedbacks will be appreciated.

I know also that the cheapest way is to make an half-slide! How do you do a clean cut, on the router?

Thanks for the info.

[richard brown]

The canham back is twice the dollars and a serious pain in the ass. Don't know the dayi...... but have a shen hao 617 camera and the back looks great. I think it is your best bet .

[Michael Alpert]

I know also that the cheapest way is to make an half-slide! How do you do a clean cut, on the router?

All you need is a utility knife and a steel straight-edge. I made a part-slide with a 4x10 proportion, resulting in one negative per sheet of film, with a large blank margin on the sky edge of the negative (the bottom of the ground glass). The slide took ten minutes to make. I used the rest of the dark-slide to make a mask for my ground glass. The slide is easy to use, I like the less-elongated 4x10 proportion more than 6x17, and I process all of my negatives together, using the same equipment and method. Once you use a dark slide, you'll quickly learn if you actually see the world in a panoramic sort of way.

[Cesar Barreto]

I'm not trully happy about 2 Shen-Hao 6x17' backs I bought, since both are scratching my films and one is clearly out of focus. They're prompt to correct those issues at the factory, but I was also thinking about giving the Canham a try, although Richard comments are actually new to me. How come this turns to be a PITA? Could you please say another couple of words about it? Thanks, in advance.

[vinny]

The first shen hao back (6x12) was way out of registration compared to any fidelity film holders I own. I returned it after wasting lots of film for a new one which is spot on. The shiny edges around the gate reflect on onto your film (now made black with a marker) and I never get the full useable area w/o a bit of cropping. The canham's do come up here used on occasion and I've not heard anything negative about them until the above post.

[Ginette]

Thanks Michael, I will try to cut one.

It look like you have to be lucky to find a good roll film unit at the first time!
Any feedbacks for the Dayi and its masks?

[Cesar Barreto]

Hi, Ginette.

I also have a Da Yi 6x17cm camera and suppose this back for 5x7' cameras must follow the same basic design. It works fine, but maybe you may find the need for some "improvement", just like fixing some light leaks, tightening loose screws and so on. Mine has seen some hundreds, maybe thousands of films and already shows some ageing effects and I'm considering buying a new one. The masks are somewhat crude, but they do what they're supposed to, so it hasn't been any source of trouble so far.

[richard brown]

My experience was that with the canham, the 9V battery doesn't last long and the motor seemed to drag even with a fresh battery as if the motor did not have enough juice to keep tension as well as advancing the film. Turned out the problem was the levers that locked the two halves together had to be backed off with an allen key or they were too tight. When I backed them off, the unit did not seem as tight. I don't know why a mechanical film back wasn't tried but Keith Canham is brilliant (and a great guy) so he likely had a good reason. The Horseman 617 back used by Ebony and Horseman seems a better idea. I had a vpan 617 and the film holder while heavy, it was a nice unit for that camera. If the weather improves I will get out with my shen hao 617 in the next few days and see how it works. I think the old shen hao 617 backs that attached to a 4x5 camera may not have been built as well..... I know that my new shen hao is far better than my old one build wise. As for scratching on that shen hao, my friend here in town bought a brand new linhof 6x9 roll film holder (big bucks) and it had metal filings in it that scratched his film. Hadn't been properly cleaned at the factory. No guarantees. I still have my art panoramic 617 which is the simplest and the best!