Since starting this thread I have tried another roll of 35mm Efke 25- all close ups of rusting metal and peeling paint on an old door- chosen to show up the film's sharpness. I developed the film in Rodinal and have just made some 6 x 9 inch prints on a Leitz Valoy.
I am much more impressed with the results this time - sharper than before, though I don't know why as I've not done anything different this time.
I do like the overall look of Efke 25 so rather than try Pan F, which some of you have said is no sharper, I plan to stick with the Efke, but perhaps try different developers.
Thanks again to everyone for your helpful comments.
Alan Clark