Originally Posted by leeturner
First of all, if your color head does not have a density filter built in, you can reduce the lamp output by switching to a less powerfull bulb. There are 250 w, 100 and 75 w bulbs avail. of the same design. Downrating is safe (the other way is not, as the current is much higher and heat also came into play)
If this proves insuficient, you can insert a piece of white translucent Perspex above or under the light mixing box in order to reduce lamp output. It's cheap, and esay to install and to change. Inspect it often because with heat, this material becomes yellow and will change the filtration unexpectedly.
Next, without filter, you've got a quite grade 2 exposure, but the paper's speed if greater (see Ilford fact sheet for your paper). As a filter is put into the light path, it will absorb power so the light reaching the paper will be weaker, provided the filters are not worn out. (be carefull if you open the head for cleaning not to put things like WD40 on them, it will destroy the fine metallic deposit making them filters... Been there, done that...)
And go to Mr Butzi web site (or others) and calibrate your dichro head to get proper grades with your setup. Print a grade/filters conversion table and you will have a speed matched head perfect for printing. You can calibrate it for every paper you use, different manufacturers have different "grade" meaning...
Last but not least, consider printing with plain under the lens filters. If your enlarger head is not sturdy and stable, moving from one filter setting to another (say for burning in) during a print session will move the head and ruin the current print. It is much easier to change a filter in a filter holder than to ensure your head doesn't move during dial in. If your lens has a front filter thread, you can put a Cokin or Lee filter holder on it and use this as a filter holder for Kodak, Fuji or Ilford filters. Buy the under the lens type or the Agfa ones. They are made to go above or under the lens.