today I bought an Omega D5 enlarger, with a 3-lens turret. I want to make sure it's parallel in all aspects, from lens to neg carrier to enlarging surface. How can this be done most effectively. I have searched the forums for a while, but cannot find good advice.
Try here. Click on the "ask Harry" tab. This guy knows everything useful about the Omega enalrger and has parts for many models.
John Douglas has a downloadable catalogue for the D5 & D3 in PDF form.
He also offers a lot of photo related info.
I use a small laser scope from an air rifle. It can be adjusted in two axis and sets firmly on the baseboard. I then put a mirror on the lens and the negative stage and adjust until the spot reflects back on its self. Works well and cost about $20. There are commercial devices that do the same. You can adjust the beam for perpendicular by rotating the laser - if the spot doesn't move it is correct.
I had a D5-XL and used the "zig or zip align" tool (I think it was called)... it was a mirror based system... I don't use the D5 anymore but still have that device, let me know if you want more info and I'll pull it out from where ever it might be and get back to you...