Wheel on side of lens

[Alan Parks]

I have a Goerz Dagor 12in lens I use on an 8x10 camera. It has an Ilex "#4 Acme Sycnhro" shutter. On the side of the shutter is a wheel that has "0 Red, 5 WH, 2 0 Blu, 23 Yel" printed above it. As I spin the thumb wheel I can make out small colored dots on it. Next to the wheel is a silver lever. Does anyone know the pu rpose of this wheel and labels? Alan

[Chauncey Walden]

It's the sync delay setting for flashbulbs.

[doc]

Hi Alan, I have the same setup, and I don't know how to use it either. I wonder if someone could elaborate on the fine points of making photographs with this device. David

[Tony Brent]

It's been a while since I fired one of those off, but I would be willing to bet the numbers refer to milliseconds of delay. 0 for X sync, and different delays for different flashbulb types. (A common setting was about 20 ms)

[Michael S. Briggs]

S. K. Grimes has an explanation and photograph on his web site on the page "Ilex Acme and Universal shutters", http://www.skgrimes.com/ilex/index.htm As other posters stated, it sets the flash synchronization, specifically the number of milliseconds the flash is fired before the shutter opens. For electronic flash you want the zero setting. A rather strange aspect is that in order to obtain flash synchronization, you must cock the shutter twice, using both the regular lever and the lever above the synchronization setting.