Brightness difference between the Elmo ST1200D / ST1200HD M&O

[Matthieu van der Sluis]

I recently bought the ST1200HD M&O.
The ST1200HD is a very quiet machine compared to my ST1200D and it runs like new.
Realy nice, how you can switch and regulate the sound of both channels.

Only the ST1200HD version is less bright than the ST1200D
i switched the lamp, but that's not it.
What can be the cause of this?

Can it be a setting of the Shutterblade?

[Dominique De Bast]

Did you check if both projectors are set on the same voltage ? As said previousely, the projectors were set in the factory at a higher voltage than the domestic one, to protect the lamp. In Europe we used to have 220 volts at home (now, it's 230 but can be 240), so the projectors were set at 240 volts. Some people changed the setting (so, for Europe, they put 220 volts instead of 240 volts).

[Steve Klare]

Hi Matthieu

Dominique is correct: a different voltage setting can make a big difference in brightness (-lamp life too.)

Something else I saw once that made a difference was the cleanliness of the back of the lens. I noticed my ST-1200HD was dimmer than my ST-800s, even with the same lens, and despite the 150W lamp in the '1200 vs the 100W in the '800.

I took the lenses out and noticed there was this fog of emulsion dust (-and maybe other nasties) on the rear element of the '1200's lens which made a big difference once I cleaned it off with a cotton bud.
(-'twas kinda' disgusting!)

There can be internal fogging of lenses too. Have you tried swapping lenses?

(BTW, are they the same type lens in the first place? "f1.0, f1.1, f1.3"...etc.?)

[Matthieu van der Sluis]

Yes both uses a Braun f1.1 11-30mm lens from two Visacustic projectors in a v. Eck Elmo lensadapter.
I swapped them, but that didn't changed.
i cleaned the lenses in the lampholders and on both projectors they are cracked in two, but almost invisable.

[Matthieu van der Sluis]

Thanks, for the help.

Yes, the old ST1200D is on 220V, while the ST1200HD is in 240V
How do I change that?
Normally I can put in a flat screwdriver.
Is that under the cap?
Do I first unscrew the left and right screw, or does it come off the circuitboard than?

I like the brightness of the ST1200D and do not care about buying an extra lamp for €9,99
Shall I change the ST1200 to 220V too?
Or will it ruin my projector much sooner?
I do care about ruin my projector.

[Rob Young]

Hi Matthieu. I'm hoping that your new ST1200HD is the one we discussed regarding the rubber shutter in another thread? If so, I'm so glad that it runs well. These can be fabulous, robust projectors.

I will leave the voltage settings to the more knowledgeable, but one thing to check is the contacts on the lamp holder.

If your ST1200HD is like mine, then the lamp fits by pushing the 2 lamp pins into spring loaded brass contacts on the lamp holder. It is worth checking if these are clean and not oxidized.

ONLY DO THIS WITH THE MACHINE UNPLUGGED! Try spaying a little contact cleaner into the contacts on the lamp holder and cleaning with cotton buds, or very, very mild sand paper. It is tricky, as there is only a fine gap between the spring loaded contacts. I used to push a piece of paper under the lamp holder when doing this to catch any debris. Then clean off the machine and try a new bulb.

I have seen even new bulbs with slightly oxidized pins. Some bulbs, even though "new" are older stock and the pins look dark instead of a shiny silver colour. It is worth giving these a light sand paper before installing.

The contact between the lamp pins and the Elmo type spring loaded contacts in the lamp holder is vital. I had mine not even firing up a lamp when they get oxidized.

The split in the protective glass between the lamp and gate is normal. It is there to prevent the glass breaking when getting hot / cold.

There are also adjustments for aligning the lamp holder on the ST1200HD, but try the above first.

[Matthieu van der Sluis]

Yes it is that projector and it is like new.
in the back,... everything is still shiny.

To change voltage I have to take out that cap.
It has 3 pins on the other side, that goes into the holes that corresponds to the right voltage.
The opening on the side shows the chosen voltage after pressing the pins in again.

I've tried 230V first, but I realy like the brighter picture of 220V.

I will now check and clean the pins and holder, cause the ST1200D wins still, but ever so slightly.

[Rob Young]

Matthieu, have a look at page 6 of the manual as well;

Elmo - Projector - ST1200 - Service Manual (super8-welt.de)

This describes moving the lamp holder to obtain the best brightness.

Let us know how you get on.