Different media can reproduce a different range of colours (known as the gamut of the medium) So your screen can do a decent flourescent green, but can't do a deep black, and most printers are the opposite.

Screens use Red, Green, Blue (RGB) lights added together, Printers use Cyan, Magenta, Yellow and Key black (CMYK) usung a subtractive mix. (Traditional printers can also inks of a specific colour for spot colour, but that requires expensive plates to be made) The range of colours that can be reproduced is known as the colourspace.

A profile is a way of accomodating the quirks of the output device. When a set of numbers is converted into an output, the exact colour depends on the shades of the components used by the device. The profile is a way of converting the numbers so that they come out at the intended shade. The ICC standardise the file format for these.

I use a monitor profiler so my monitor displays realistic colours, and I am pretty certain that if a photo looks a certain way, when I have it printed at the photoshop it will come out just the same.

Adobe RGB is a neutral non device specific profile that Adobe products use and embed in certain output files so that printers know which colour is which.

Tim G tells me that Lulu aren't very consistent at printing colour, so that may be why they aren't fussed about profiles - their printers aren't good at honouring them.

How essential is it that you get exact shades? Unless you are doing photos, does it matter?

As for bleeds put your picture fully ioverlapping the bleed area, but keep any important detail safely away from it. When the pages are trimmed, you will get size variations of 1 or 2 mm typically. If you put the picture up to edge of page, but not the bleed area, you might get some of the picture trimmed off, but equally you might end up with a very thin white margin. By printing in this area (known as bleed area) the vaguries of trimming don't result in white bits. The alternative is to have a decent white margin all round your pages.

Lulu's trimming can be erratic depending on printer location and so on. As such even bleeds delivered to their specs can fail (see Covenant's early printings).

Somewhere in the FAQ it also used to mention that they prefered an RGB (ie screen) colourspace for reasons best known to themselves. No idea if this still holds.

-Matt

Realms Publishing

Arise thee, oh thread of LULU Fu.

Unless you have a colour calibrated monitor then it will not accurately show colour. Unless you have a colour calibrated printer then it will not accurately print colour.

Things like colour covers are also affected by the card stock and colour. Bright white ppaer displays colour differently than matte white or a creamy white. David has noticed this recently on his Solipsist printings, for example.

I think he preferred the LULU paper (a cream, almost) and cover.

Thanks for the useful comments and the link to the thread.

I shall go and Digest them some more!

---
Dom Mooney
http://www.bits.org.uk/
http://www.powerprojection.net/

I did indeed like the colour of the LULU paper Gregor, though the weight was much lighter than Fidlar's. The book is perhaps 75% of the thickness from LULU as it is from Fidlar.

http://www.solipsist-rpg.com/ - http://cubicle-7.com/starblazer/