Are Source 4s getting harder to bench focus?

[kicknargel]

I was trying to solve the problem that one of my Source 4-on-a-stick spotlights (with HPL 750s) was significantly dimmer than the other. In trying to bench focus the dimmer one, I determined that I needed deeper penetration of the lamp. But I discovered that the penentration was maxed out--the lamp holder was up against the stops inside the fixture. I find in general I bench Source 4s with the maximum penetration in the range. It seems to me that these lamps are shorter than they used to be.

Am I imagining this?

For what it's worth--the brighter one had an Oshram and the dimmer one had an Ushio (shoot, it might have been the other way around). I put an identical lamp in the dimmer one--the problem got better but not all the way. I guess I should try switching the caps and see if the problem follows them.

 

[Footer]

You could have had X lamps in which burn longer but have a lower color temp. You could have had a 120v lamp and a 115v lamp. You could have had two different wattages of lamps. You could have had a dirty fixture. you could have had a cap that with a lamp that was not properly seated. You might had a lamp camp that is not properly seated in the fixture. You could have had a fixture with a reflector that is flaking. The list goes on. The only real way to tell is to swap around caps. The source4 has one of the worst bench focusing mechanisms ever in my opinion.

 

[church]

I have also experienced problems with S4s. I have one fixture where I cannot get the bench focus correct. The intensity is good but one shutter is not focused. When yo push in the shutter you get a double image of the shutter but no hard cut-off of the light. I have never seen this before in over thitrty years of lighting using fixtures from many manufacturers.

I have tried everything: swapping the cap, swapping the lamp, installing a new reflector, changing the lens tube, rebuilding the shutter assembly etc. - no success. I called the ETC technical people multiple times and we tried different ideas and eventually we gave up. I have decided I just have one fixture that cannot be bench focused/set-up to allow all four shutters to be used.

There is much I love about S4s but there are some things ....!

I should add I only buy Osram lamps and only one type so it is not a lamp issue.

 

[icewolf08]

I have also experienced problems with S4s. I have one fixture where I cannot get the bench focus correct. The intensity is good but one shutter is not focused. When yo push in the shutter you get a double image of the shutter but no hard cut-off of the light. I have never seen this before in over thitrty years of lighting using fixtures from many manufacturers.

I have tried everything: swapping the cap, swapping the lamp, installing a new reflector, changing the lens tube, rebuilding the shutter assembly etc. - no success. I called the ETC technical people multiple times and we tried different ideas and eventually we gave up. I have decided I just have one fixture that cannot be bench focused/set-up to allow all four shutters to be used.

There is much I love about S4s but there are some things ....!

I should add I only buy Osram lamps and only one type so it is not a lamp issue.

You realize that the standard set-up for a source 4 has the shutters in three different planes. Therefore, by definition, you shouldn't be able to have them all in perfect focus at the same time. Now, it sounds like your issue goes a little further than that, but I thought it was worth mentioning.

 

[church]

You realize that the standard set-up for a source 4 has the shutters in three different planes. Therefore, by definition, you shouldn't be able to have them all in perfect focus at the same time. Now, it sounds like your issue goes a little further than that, but I thought it was worth mentioning.

Unfortunately you are correct the problem is way beyond the shutters being in the four planes. It has driven me mad because I now hate using this particular fixture becuase I know it is the "runt of the litter". It is also problematic because I am reluctant to hire out the fixture because I know it has this problem which means it is not paying its way. Ultimately I may end up having to scrap it for parts which is quite frustrating for a fixture that is still not depreciated for tax purposes. Oh well!

 

[mstaylor]

This will sound dumb but have you swopped the shutters around. I haven't had this issue with a S4 but I have with older style lights, 369Qs and others. I don't remember what about the shutter that was causing the problem but it was the shutter, not the light, burn spot maybe.

 

[JD]

I have also experienced problems with S4s. I have one fixture where I cannot get the bench focus correct. The intensity is good but one shutter is not focused.

"I have one", that is the interesting part to me! Yes, there is a spacing error, but this would show up on every light. You have swapped caps and tubes, so there isn't much left to the fixture other than the gate and the reflector. Since you have had it apart and rebuilt that section, with special attention to the problem, we can almost assume that the problem is not in the gate. That leaves the reflector not much else. Have you tried moving the gate parts to another light?

Really interesting! Let us know what you find.

 

[church]

"I have one", that is the interesting part to me! Yes, there is a spacing error, but this would show up on every light. You have swapped caps and tubes, so there isn't much left to the fixture other than the gate and the reflector. Since you have had it apart and rebuilt that section, with special attention to the problem, we can almost assume that the problem is not in the gate. That leaves the reflector not much else. Have you tried moving the gate parts to another light?

Really interesting! Let us know what you find.

If I think about it the only thing I have not tried is to seperate the gate from the barrel and try a different gate assembly (shutters and plates only) I will try that.

 

[kicknargel]

Not to re-hijak the thread, but I'm still interested in whether other people find that to bench focus a S4 they are maxing out the penetration, and sometimes need a little more. Have HPLs gotten shorter (or at least filaments closer to the base)?