23CII diffusion bulb

[zachsilvey]

I thought the 23CII was a condenser enlarger but when I took a look around the one I picked up today it has a florescent bulb with an aristo power ballast. It this how it came from the factory or has this been converted.

[BetterSense]

I think it has a cold-light head installed on it. Some 23C enlargers have condensor lenses in the top; mine has no condenser lenses but it has a grey plastic diffuser just above the filter slot, and an incandescent bulb.

[zachsilvey]

Mine has the same grey plastic diffuser, the previous owner must have put in the cold head. Is this a good thing or a bad thing. Or will it not make much of a difference.

[dances_w_clouds]

I haven't see many posts on the comparison of the two different light sources. All three of mine have the bulb with the diffuser plate so I have nothing to compare it to. I have been thinking of getting a cold head just for comparison purposes. I have seen one in the Craigslist in my area but haven't responded just yet. I am sure there will be posts to follow for the advantages and disadvantages of either one.

[BetterSense]

On the diffusion ones, does it matter what position you place the upper bellows at? I know it's so you can focus the condenser heads, but on a diffusion head I don't see how it matters so I always just put it all the way down on the theory that it will be faster (brighter) that way.

[dances_w_clouds]

I see what you are saying but it just seems wrong. There must be a reason behind the adjustments on the light head. Mine seems to work quite well on the settings that are on it. There is no settings for the 6 X 4.5 negs I use but I just put it closer to the 6 X 6 marking than the 35mm . But I guess if all else fails, read the instructions.

[Agamennon2000]

confused....Do I have to use an enlarger bulb or can I use a regular light bulb?

[MattKing]

confused....Do I have to use an enlarger bulb or can I use a regular light bulb?

Enlarger bulbs:

1) tend to be more consistent as to light output;
2) tend to have more frosting and more even frosting;
3) tend to be more consistent about having their filaments near centre; and
4) don't have writing in the wrong location .

Many enlargers require bulbs designed for particular voltages, particular wattages (??) and particular bases.

That being said, some enlargers do work with some ordinary bulbs, but you shouldn't count on it.

Matt

[BetterSense]

Also, the rated life on proper enlarger bulbs is shockingly low. I just bought a PH140 (I think) for my 23C and it says only 50 hour life.

[ann]

don't panic about the life of the bulb

we have several enlargers in the lab that use the standard enlarger bulb and i can't remember the last time i had to change one, and i mean years .

with a cold light head the light source sits as close to the negative stage as possible.