D2/cold head, settings?

[PeteZ8]

I picked up a D2 with a cold head, 4x5 negative carrier, and 150mm lens today off of Craigslist for a song.

I tried it out tonight and I'm struggling a little bit with settings. This thing is BRIGHT! f/22 for 10 seconds seems to be in the ballpark for an 8x10 on RC paper. 10 seconds is still short to me should I want to do dodging and burning, as well as being hard to get fine control over exposure. I do have one more stop on the lens but I'm concerned about sharpness stopping down all the way.

Also, is there any way/need to use Polycontrast filters on these? I'd like to add a little more contrast to the prints. I use a PCS-150 for 35mm so controlling contrast is easy. On Ilford paper just turn down the blue and turn up the green; done!

 

[David A. Goldfarb]

The orthodox way of using VC filters with a cold light head is to use filters that go under the lens. I believe Ilford still makes a set with filter holder.

The unorthodox way, which I use on my D-II, is to use 6" filters right on top of the negative carrier, held down by the head.

Do you have the Aristo Hi-D head? That's what I have, and it is indeed bright. I highly recommend using a compensating timer like the Metrolux, which can give accurate exposure times to 1/10 sec. Lacking that, you could put an ND gel (an ordinary lighting gel will do) between the bulb and the diffuser, and just remove it when you print big or otherwise need more light, but if you're printing on VC paper, see what kinds of times you get with a filter in place first.

 

[PeteZ8]

Thanks for the reply. I contacted the seller and I am going to pick up his digital timer on Monday. He also had the arm for the PC filters.

The seller had a room FULL of equipment... this could get dangerous!

 

[PeteZ8]

As luck would have it, I stopped at my local camera shop and someone had dumped an entire D2 (condensor) with all the goodies. Copy stand, some type of tilting negative holder to correct schiemflug errors, Yankee tanks, etc. Managed to grab all of the 6" PC filters, a .1 second incriment timer, Beseler color drum (for my roller), and a few other gizmo's for $30. I think they just want darkroom stuff gone I may go back and raid the box again next payday!

Thanks again!

 

[David A. Goldfarb]

That perspective correction neg stage is handy and not easy to find.

 

[PeteZ8]

Thanks David! It looked like a very handy gizmo.

They have a ton of parts, if anyone is looking for neg carriers, lens cones, or a copy attachment let me know. I'm sure they will be mroe than happy to let them go for virtually nothing. The copy attachment looked brand new, and they had some brand new neg. carriers too. I'll probably stop in there again on Saturday.

 

[Ronald Moravec]

Aristo makes a dimer good for 3+ stops.

Expose a piece of 4x5 film to a white board keeping it out of focus. It becomes a ND filter for the top of the neg carrier.

 

[PeteZ8]

Excellent tip Ron! Thank you.

BTW someone asked earlier what cold head is on the machine, it is an Omega II cold head which actually brings up another question. Why are there TWO power cords on the head???

 

[David A. Goldfarb]

One power cord controls the light, and one is a heater. The heater will keep the bulb warm and reduce the ramp time when you turn the bulb on and off. It's not as good as a compensating timer, but it's much better than nothing. The bulb plugs into your timer, and the heater stays plugged into the wall all the time while you're printing. It's a good idea to leave the bulb on for about 15 minutes so the whole system warms up before you start printing.

 

[PeteZ8]

Thanks David! I forgot to plug in the 2nd cord last night and had a few very inconsistant prints, it was driving me nuts! It did get better after 4 or 5 when I guess it warmed up naturally. After I plugged it in all the problems seemed to go away. Now I know why! I had figured it had something to do with consistancy; ie voltage regulator circut or something. Now it all makes sense.

I will try the 15 minute warmup too, great tip!

 

[Christiaan Phleger]

If you can find it, ZOne VI made a Cold Light Stabilizer, which has a extra plug outlet for the heater and a sensor for the head, also has a dimmer so you can fine tune it. I've tuned mine so that most average negs from the main film I use processed my most used developer at the avg temp for the usual time gives a mostly correct print at 5.6 (sharpest F-stop on that enlarging lens) for 10 seconds at 8x10. I use a light meter on the base board at the 8x10 height and record the settings on a piece of tape on the stabilizer, so I'm able to recall the settings if they shift or drift, but the head output is remarkable steady. I have an Aristo V54 bulb.