Colour Seperation

[coza]

Thanks Gary for the great effort and help.
I am trying to get extra drums the RISOGRAPH machine we have just bought and I would like to bring in color in my printing.
I should have brought this up in the begining and mentioned the digital printing capabilities of RISO
On more complex illustrations than your sample Gary, the tricky part is the copy setting on the machine itself.
I have tried some samples but with little joy.
I was hoping we would be able to go further than CYMK so even if it means investing in a further one or two extra drums would be worth it
and they are expensive...lol!!

From what I remember Albacore is right,
you mainly work with Spot Colour Cartridges, unless you have an updated CMYK Riso machine.

I made up Ads for a guy who ran a 2 Col A3 - Riso sometime ago - he was using Coreldraw as his graphics program.

If I remember correctly, all we did was work in 2 colours on the page for proofing purposes, then - when it was time to print we would simply create another 2 separate pages, cut and paste the separated colours on each of those pages, turned everything to 100K, then sent them through to the Riso using it's Printer Driver, with the pages matching the colour drum on the machine for each of the colours. Thinking about it now, you could possibly do it in 2 separate layers on the page.

The paper plates were made for each colour, and off things went on the run in hope for no jam along the way.

What have you tried so far? How many colour heads do you have on your Riso? How tight will the registration be in the colours, I used to spread/choke things manually a bit to close a few gaps that could occur.

I have not seen or have any experience with a CMYK Riso machine, but I believe they do exist, would love to know the LPI they can produce on the plates they use.

[qibla]

Thanks guys for the response.
Now I am also learning quite a few things here.
Yes I do have black, green and red drums for burning the skins - masters - but for a full color photograph for example I need to understand how best to seperate the different colors for best quality.
For other graphic designs spot colors is fine.
There is a RISO HC5500 which does the whole job but quite pricey.

[qibla]

Ok got it! Good for me!!...lol!
http://paperpusher.ca/guide_to_printing/