Ok, so I have now got myself some inkjet transparencies and have created some digital negatives, I knew that the exposure time would be different but its like night and day!
Oiled paper = around 10 minutes
Transparencies = around 1 minute
Yes thats right, 1 minute per print, I tried a print at 10 minutes and 5 minutes and both were overexposed massivly, I have put the timer on basically the minimum that the face tanner can go on and its pretty much spot on, I will take a photo of one of the prints, its amazinly sharp, high contrast, really nice colour and no mess or contamination on the print.
The inkjet transparencies aren't that cheap, but printing 4 on an A4 sheet its not too bad, I think it works out at something like 25p a sheet but these negatives will last and they really are amazing to look at - this would still be cheaper than a large format negative so I am happy
I might get myself one of those exposure timers that cuts the power off making it slightly easier to get the exposure right, I might also create a colour chart with a gray scale and then expose it at different times to see at which point the best contrast is attained.
I am amazed at the sharpness of the print though, its even on rough watercolour paper but you can tell its sharp.