View Full Version : 1919 Zeiss Amatar CLA?

Sven Schroder
19-Mar-2007, 13:32
Hello all

Here is something I've never come across before, slow speeds that are about a stop fast rather than slugish, the shutter in question is an ICA badged dialset compur 2 in which the amatar is mounted. It sounds as if the geartrain (if thats the right word) is worn, as you cock the shutter and on release. Will a CLA sort it out? or do I look for a replacement shutter? It feels as if it will need new parts. I've been using a shorter 135mm version and enjoy it prompting the purchase of a longer 165mm but this shutter is not trustworthy.

Any related experience? Any advice?

Thanks and Regards


Gene McCluney
19-Mar-2007, 13:43
Dirt or gum or dried oils on the slow-speed gear train of leaf shutters can absolutely make the slow-speed settings run fast. Consider...as you set the lens to slower and slower speeds a spring-loaded gear train is allowed to extend out further and further from start position, and as the shutter fires, a mechanism pushes this gear train back to start position, the length this gear train runs is what determines the speed. If the gear-train doesn't fully extend, due to gummy gears, then the speeds will be too fast. But, bear in mind that the accuracy of all your shutter speeds on most leaf-shutters is also dependent on the tension of springs, and springs weaken over time and have to be re-tensioned. A CLA should solve both problems.

Sven Schroder
20-Mar-2007, 02:11
Thanks Gene

That makes sense, just something I'd never come across before, having fixed a number of rim set compurs with "Tuiteka's Shutter Repair Fluid" a solvent of some sort, but the Amatar will be off for a Pro-CLA.

Thanks again

Gene McCluney
20-Mar-2007, 06:57
It has been my experience that older shutters that use an air piston to control slow shutter speeds can get slow when dirty, but all leaf shutters that use a gear train for slow shutter speed timing can go either fast or slow when dirty depending on how the gear train is designed. It seems almost all leaf shutters use spring pressure for determining the "fast" shutter speeds.