Luc shutter issues

[fatherdougal]

Hello,

I read up on the Luc shutters on the forums and found it very interesting, so I bought one for my barrel lenses. I just received a luc shutter that supposedly was in working order. However, I have run into a couple of problems and would be very thankful if anyone with more experience would like to share their thoughts!

On instant mode and manual mode the blades fully retract. However when using bulb mode the blades will only open 80% or so. Is this normal behaviour?
I also noticed some light leaks (see the attached picture) at the edge of one of the shutter blades. Is this a common problem and do you think it would be fixable by sending it in for a CLA?
I've also attached some additional pictures for you too see if there are any obvious problems apparent that might help in fixing these problems.

Looking forward to hear your thought!

[Jody_S]

Assuming you've tried with a long-throw cable release, I think your shutter may have excessive wear. There must be some slop in the pins at the edge of the blades, or else someone has assembled it incorrectly. It's a very simple mechanism, anyone should be able to service it if it is improperly assembled, but there are no replacement parts of course.

[Robert Opheim]

Repeating what Jody says above; As far as the blades only opening 80% - that probably would be caused by the cable release (length) throw. You need a very long cable release throw for this type of shutter. I don't see the light leak that you mentioned in the photographs of the shutter. There can be light leaks between the LUC type shutter and the lens - It needs to have a tight fitting gasket of some sort. I have used rubber washers or even rubber bands with my shutters.

[Havoc]

I don't see the light leak that you mentioned in the photographs of the shutter.

First photo, edge of the shutter blades at about 1h position. There is another smaller one at the edge of the shutter blades between 10h and 11h.