Colour profiling medias

[Robert Lambie]

ricahrd at raccon graphics has setup a company that sells profiling software john. for the life of me i cant remember the name, but calling raccoon graphics should shed some light..

personaly i think rodney gold mentioned about tweaking settings in already made profiles for say vinyl is easier. not saying i have a clue how to go about doing this 100% correct.. but did go through some precedures recently with dropping and increasing ink output, speed, pases etc and i think i can start to see where he is coming from. 🙄

[John Cornfield]

Yeah you can tweak those things but i think you are starting from a point where the maximum level of ink that the media can take on four colour lay down. So the minute you adjust down the way you loose density and get a washed out image go up the way and you get drying issues. Profile sets the optimum ink level and then adjusts for the various settings to get the maximum quality for each dpi profile. I beleive this is where the skill comes in to it.

We have bumped up and down the ink levels when printing on fabric/flag materials to stop pooling/bleeding.

I find the vinyl profile on onyx for md5 just a little light and would not want to drop it down more and i don’t think it will take much more ink.

Just fishing on the boards to get a straight answers to my profiling questions as i am getting a little hacked (hot) off that i am not getting the best from my equipment.

[Rodney Gold]

Profiling is fairly complex and unless you are doing giclee type work for photographers etc and really want to run a color calibrated workflow , it can be achieved easier.
You use densitometers , screen calibrating spiders etc to linearize the material and set up a colour workflow , a good system will cost 2k+. Its a 2 part thing , firstly to otimise the media and printer and secondly to calibrate the computer system to show what you are going to get.
If you are going that route , then you have to aim the output of your machine at the real high end of the market. Giclee printing is sort of archival/museum VERY high quality output. Problem is 2 fold , the 4 colour machine cannot get the tonal gradation or even come close to the colour gamuts required and worse than that , the output of solvent or eco-solvent printers is not color fast for appreciable times , no where near what the archival or art print industry require. Neither can you print on a lot of papers/substrates that are used .
Essentially what you first want is a sort of What you see is what you get scenario. (WYSIWYG)
The way to do this is download a colour chip chart , you can either download from http://www.pantone.com (under support I think , there is a huge Panton EPS chart you can DL and print) or go to www. rolandgga.com , under support go to your printer model (soljet/sp300) and DL the colour chip chart there , and print it.
All you do thereafter is use your monitor controls to match what you see in your rip preview to the printed output , or match your customers colours to the printed output.
Profiling using densitometers etc depends on your RIP , it has to support the particular densitometer etc. That’s one of the reasons I would rather use Colorip (WASATCH) Rip than any other , it uses standard ICC profiles (some rips have proprietory ones) and it supports just about any profiling device. The Help files with this RIP and Wasatch’s web site help files are rather good at explaining all this and good in terms of color theory and how it all works. http://www.wasatchinc.com
I beleive that the Cadets and grenadiers are not “allowed” to use colorip (rolands oem version of Wasatche’s softrip), but if you get a copy (version 2.1 is the latest) it will work and will give you a ton of profiles to play with too – just tweak em to suit the solvent based machines.
There are a huge amount of factors that can be adjusted when tweaking a profile and determining ink loading
halftone method , dot size , total inks , color seperation rules (very powerful for profiling media) , head speed , drying times , color correction curves , ink limiting , rendering intent etc etc.
When we get a good media , we stick with it. We only use 2 medias for white vinyl , grafityp s22p (similar to 181 , polymeric) as our “cheap” media and Starrex (x-film) 5-7 yr cast polymeric as our premium stuff. Both are pretty pricey per sq meter but print beautifully and the extra price per sq m is more than made up for by the fact that you can print right EVERY time. The cost of media etc is actually not much of an issue , its printability and suitability is.
Using profiling equipment WILL save a huge amount of time experimenting with various settings however , but fiddling around often teaches you a lot more , cause and effect stuff , and gives you a better understanding of color workflow.

[Robert Lambie]

andrew and i were messing around best art of today tweaking profiles.
what youjust said about better understanding of how it works is certainly coming to light.. i think we acheived allot just by having a play with different vinyls.

[Chris Wool]

rodney have you any idea whots happened in ver 2.1 as i get odd spurious colours croping up mainly from bitmaps ver2b iam sure did not show them have you noticed or just me.
chris

[Rodney Gold]

I haven’t seen that at all.
With 2.1 you must just re save your old profiles , IE just load it , change something ever so slightly and re save
Are you working out of Corel?
I suggest changing all bitmaps to cmyk in Corel as well , and exporting as a cmyk. Or alternatively , take a bitmap you import and change it to a bitmap (again) in corel (time consumig and it makes big files)
Check to see if its a Corel problem too , easiest way is to take the bitmap you used that gave you odd colours and just bring it into the RIP (it accepts jpeg etc) and see if it exhibits the same problem.
Can you post an image of the spurious color?

[Chris Wool]

its just noticed on two jobs done on 2b before : customer said whots these little mouve bits they wernt on the last ones ok though same file just re riped in 2.1 i will go back in to 2b on the other machine and see if i can find a difference in the profile thought i had put in same alterations

chris
ps just noticed marked improvement with avery mp13000 profile ink adjusted been using spv-g gloss slight alterations which in 2b very nice

[Chris Wool]

also heard that bp are moving away from troup rip might be hearsay though