Are Chamonix WP Holders Compatible With Seneca Back?

[Scott Sharp]

I have a Seneca Whole Plate (6 1/2 x 8 1/2) format view camera. An Improved Seneca View, circa late teens to early 1920s. Vintage Whole Plate film holders are nearly impossible to find as most WP camera owners know.

The Chamonix WP holders look like a good option. Any idea if they are compatible with the Seneca GG back or if Chamomix can make holders that are?

Thanks, Scott

[Oren Grad]

If you can provide measurements of your back, I can check for you. I need the width of the opening for the holder and the distance from the far stop to the beginning of the locking groove.

[Roger Thoms]

Scott asked me to post the measurements since his camera is in the shop. My WP Seneca is a City View Camera, should be the same as Scotts Improved Seneca View.

The width of the opening is 7 7/8" and the distance from the far stop to the beginning of the locking groove is 9 1/8"

Roger

[Steve Hamley]

My Chamonix WP holders are 7-13/16 wide, and 9-3/16 to the start of the rib. They're also made to the Eastman standard, so if an Eastman holder fits, so will the Chamonix.

Another option is AWB holders, but they're pricier. I'd rather have the standard dark slides and pulls on the AWB. And if you send your back (or measure it), Alan will ensure the T-distance is correct.

Cheers, Steve

[Oren Grad]

I get 7 13/16" wide and 9 1/4" to the start of the rib on my Chamonix holders.

However, the Chamonix holders are not designed to exactly match the Eastman holders. The Eastman holders are a bit smaller - the one I have in hand at the moment is 7 3/4" wide and 9 3/16" to the start of the rib.

This seems like a small difference, but it can be enough to matter. For example, my Eastman holders will fit my Rittreck WP back, but my Chamonix holders won't - they're just a hair too wide.

[Richard K.]

I'm curious about how the T-distances compare. Has anyone measured this for the holders and also for the back(s)? I once bought an 8x20 Korona and included holder (couldn't tell the brand) off by 1/4" !

[Scott Sharp]

Measuring my two WP size Eastman Glass Plate holders, they match Oren's Eastman holders. Eastman measurements: 7 3/4 " wide and 9 3/16" to the start of the rib. The Eastman WP holders do fit the Seneca back.

Looks like the Chamonix WP are slightly larger though not by much (1/16th) and could probably be modified to fit the Seneca back. Does anyone actually have a Chamonix WP holder they are using with a WP Seneca camera?

Good question on the T-distance comparison. Anyone checked that?

[Oren Grad]

Looks like the Chamonix WP are slightly larger though not by much (1/16th) and could probably be modified to fit the Seneca back. Does anyone actually have a Chamonix WP holder they are using with a WP Seneca camera?

It might not be necessary to modify anything. My Chamonix holders fit fine in my Eastman backs because there's a fair amount of wiggle room between the Eastman backs and holders.

[Roger Thoms]

The Grove on my Seneca back is 7/32" wide, how does that compare to the width of the rib on the Chamonix holder?

I also measured the T distance on my back and it is 7/32", if someone could compare that to Chamonix holder.

Roger

Roger

[Scott Sharp]

Oren,

Would you measure the T-distance on your Chamonix holder?

Thanks, Scott