I recently ran into this exact problem. I made a contact proof and was very pleased with everything about it. It was "love at first sight." And that is a look that is difficult to get out of your mind's eye once it has set in.
Then when I went to print, the enlargement fell short of my expectations based on what I saw in the proof.
I discussed this at LFF and ROL saw one weakness in my Red Cones shot, soft background - likely because I used a relatively wide aperture f/8, focused closer than appropriate for infinity. This was not evident on the contact print. But it stands out as a defect on an enlargement. You might see this as a reason to recommend shooting 8x10 and making contact prints.
I take it as a reason to "never" make contact prints, or small prints (unless that is the intended finished size). Then I won't be disappointed (because of these differences) by the enlargements.
In a practical sense, I do that. I make most of my prints at 11x14 and if they don't look good they get filed away.
If they do look good, I am done.
I like that part of the plan.
looking through this, this post is helpful for me...
thanks... although the op didn't ask this, i'm sure he does find it very helpful as well.
Thanks everyone for your answers, they have been very informative and I definintely feel that I've got a little more to "stand on" when it's time for my next printing session.
There were some questions asked that I feel I should answer. I am indeed using paper from the same box, and I use the same filtration for both the contact sheet and the actual print, and I process in the exact same way.
Someone mentioned that an unfiltered light from a dichro head does not equal to using a grade 2 contrast filter. I read the "Controlling Contrast" PDF on ilfordphoto.com which claimed that a grade 2 filter should correspond to a 0 filtration setting on my (130M max) Durst Enlarger. I must admit to being a bit confused though, as the PDF had two tables, one for single colour filter settings, and one for double, and I'm not quite sure what the difference is, is this for different types of dichro heads?
The day after I wrote this post I went back into the darkroom and made a (roughly) 5"x7" print from the same negative. To me it looked a bit better, I think the very apparent grain might have had an effect on my perception of the 9"x12" print, but I also think a higher contrast grade would yield even more improved results.
I've also cleaned my lens as suggested, with the help of a rocket blower and an Ilford cloth, it was fairly dusty and looked like it had a fingerprint on the front element. I'm going to the Stockholm Photographic Museum tonight to look at a exhibition on Helmut Newton, so I won't be able print, but hopefully I should have time for a printing session during the weekend, during which I'll try out of some of the remedies suggested.
Thanks once again for your help, much appreciated!
Double filtering and single filtering have the same effect on the paper for a given grade, final prints should theoretically be the same either way.
Single filtering is simple but it requires you to adjust aperture or time with every filter change. Just like when you add a filter in front of the camera lens.
Double filtering allows you to keep the enlarger aperture and time settings more constant. The filter theoretically remains the same density. For small changes it can be quite handy, say to go from grade 2 to 2.5 dial in the filter and print, no new test strips.
I use single filtration because it has become really rare for me to need to adjust away from grade 2 when printing and because I find that with every contrast change I like a different exposure setting anyway and I use an enlarger meter to set exposure so its no streatch to reset aperture or time for whatever reason.