Aristo D2-Hi

I recently acquired an Aristo D2-Hi cold light head for my Beseler 4x5 enlarger. It comes with a Beseler (MX) adapter which consists of the circular adapter for the enlarger carriage and a filter drawer. The adapter has 3 screws around its perimeter to press against the "canister" of the cold light and hold it at the proper distance from the negative. So my questions are:

• What is the proper distance from the negative for the cold light?
• The frosted glass disk that diffuses the cold light is "loose". How should I affix it to the rim of the cold light casing so that it does not fall down into the gap created by the filter slot?
• The bulb emits a very white light which is different from the cyan cast I have seen on other cold lights. How can I tell which bulb I have as I hear the the V54 light is the best for VC papers?

Thanks.

My Aristo tube has the number printed on it.
Edge illumination will fall off rapidly as the diffuser or light source is raised from the negative. I'm not sure of the mechanical constraints on that system, but I'd consider getting it as close as possible without being in focus.

Not sure why the glass is loose like that.

I have this head on my Omega D-II, and I quite like it. Mine has a V54 tube, and I suspect yours does too, if it's of recent vintage and the light looks basically white.

The diffuser should be resting pretty much directly on the negative carrier (or perhaps the filter, which should rest directly on the neg carrier, since you say you have a filter drawer between the light source and the neg carrier), and the light housing should be resting on the diffuser.

I'm not sure what the mechanical setup of this head is with the Beseler adapter. Could it be that the diffuser actually drops below the filter drawer, and the filter goes between the bulb and the diffuser? That would be ideal if it does, and then you would position the light housing as close to the filter as possible.

Jerold, I have a Aristo D2 lamp with a V54 bulb on my MXT. There are a few similarities with what we have, so maybe I can help a bit.

When I was wrestling with light falloff with my MXT and a Beseler Dichro 45S, I found out firsthand that diffused light sources need to be as close to the negative as physically possible. Like David says above, get the diffuser as close as you can; even if it almost touches the negative carrier.

Not sure about the canister/collar for your cold light - but for what it's worth: My cold light fits in a Aristo-made aluminum collar that adapts it from the Omega D series to the Beseler M series. The plastic diffuser that came with my Aristo lamp goes inside the collar and rests on the bottom of the adapter, and the lamp goes on top of the diffuser directly. No screws, shims or spacers of any kind. The plastic diffuser is a fraction smaller than the inside of the collar. It does rattle around a bit, but there's no danger of it falling out either. Once the collar/diffuser/lamp is in the enlarger it doesn't move.

If the color of the light really is white, what you probably have is the W55 bulb. Bulb types from Aristo: www.aristogrid.com/spd.htm

Thanks for the info. I don't have a chance to test these things out for awhile but will post back when I get a chance.

I looked at the lamp with a manifier. It is a V54. Is that a proper bulb for VC printing?

Yes, that's the one.

Well, I am making some progress. With the advice here, I figured out that the frosted diffuser glass drops down to the bottom of the adapter and simply rests inside the adapter ring by gravity. The three screws in the adapter ring are used to friction the cold light housing so that the bulb is positioned just above the slot for the filter. That way the filter is between the bulb and the diffuser so it is a convenient VC cold light source.

The adapter leaks light like a sieve out the top but I can deal with that by using black tape, etc.

Now my problem is figuring out the filter drawer. I wonder if there is supposed to be a filter holder. It is easy enough to slide the 6x6 inch VC filter into the slot. The problem is that the filter is square and the back side of the adapter is circular. I could simply cut the filter to the circumference of the circle on the distal portion of the filter, but either way the distal portion of the filter will sag. I assume that the sage will let some unfiltered light pass through or "leak" and might cause uneven illumination through the diffuser.

Does anyone know if a filter holder exists for the drawer? The adapter is labeled Beseler MX. It look like the Aristo adapter for Beseler except that it is black metal, has a taller "collar" which contains the three thumb set screw, and a flip-up door over the filter slot.

I suppose I could try to make my own out of mat board but cutting the radius would be a major frustration.

i ended up getting below the lens filters -
polymax ... they weren't too expensive ..