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Again, sorry about the irrelevant content for those who are not in my lecturing class. This is just a place to store our lectures so that students can refresh their memories. This is part 2 of the 13th August 2008.
Again, many website visitors probably won’t find this content terribly relevant or easy to follow. I’m putting up some long audio files which are recordings of my lectures for Certificate IV design students. Basically as a refresher if they need to re-listen. So sorry to everyone else who finds it boring…
As promised in the last post I’m going to talk about what to do when you get colour management messages from Photoshop.
You open an RGB Image and there is a profile already attached.
What do you do? You want to Use the Embedded Profile. This will facilitate the most accurate conversions later, since if it has the correct profile attached (a very good chance it does) it is going to tell the Colour Management Module the most accurate data about the RGB file. So if there’s a profile already Use the Embedded Profile!
You open an RGB Image and there is NO PROFILE attached
Hmm This is fun! OK, maybe not. Well you have to take a guess with this one. Click on the Assign Profile and select a profile. Perhaps start with Adobe RGB (1998) since it’s common. Or alternatively sRGB IEC. Check the box that says “and then convert document to working RGB”.
Click OK, and check the results! Does the colour look OK? Does it look washed out, or do the colours change abruptly (posterization)? If they do, chances are you chose wrong (sorry try again). You could however while you have the image open. Go to File>Edit and check whether or not there is any information under “camera data 1, or 2″. If it was captured with a digital camera, chances are it’s either sRGB IEC or Adobe RGB (1998). Worth a try any way.
If you select the wrong profile, you soon see why it’s so important that you get the correct profile. And how much affect good profiles have.
You open a CMYK Image and there is an Embedded Profile Attached
Same as the RGB workflow. You want to Use the Embedded Profile. This will provide the most accurate conversions later on in the piece.
You open a CMYK Image and there is NO EMBEDDED Profile.
Ok, Don’t hate the messenger. But this is probably worse than if an RGB image has no profile. The reason is, CMYK Destination Profiles have Total Area Coverage and GCR/UCR issues to be concerned about. These control the amount of ink on the paper and also the amount of neutral colour replacement with black ink. (grays can be made up with a combination of Cyan, Magenta & Yellow. Replacing with black reduces problems)
So you could try finding out the original destination profile by asking the person who supplied the image to you. Very slim chance of getting an answer, I’m afraid. Or you could take an uneducated guess and perhaps select “U.S. Web Coated (SWOP) v2″ which is usually a photoshop standard profile. Chances are it was separated using that profile.
Now it’s obscured on this screen shot but I would recommend Checking the box that says “and then convert document to working RGB”. This gets it into a known state and as long as you embed the profile, can provide accurate conversions later.
Continuing on from the previous post, I’m going to continue talking about some of the reasons why I have recommended these Colour Management Settings for Adobe CS3 applications. We’ve started with Photoshop CS3’s settings because simply there are more to choose from.
In this post I’ll be talking about the Colour Management Policies. For a refresher I’ve included a picture of the area in the Colour Settings that I’m referring to below.
Why Do I recommend Preserve Embedded Profiles for RGB
When an image has been captured or converted to a known colour space based on a colour profile, the colour profile KNOWS the most about the colour contained within that RGB file. You could say it knows it intimately. Since it has this ‘intimate’ knowledge it can give the Colour Management Module the most accurate information during converions. So I recommend that you Preserve Embedded Profiles so it facilitates the best conversion.
Why Do I recommend Preserve Embedded Profiles for CMYK
Following along the same vein as the RGB, it’s still very important to Preserve Embedded CMYK Profiles since later you may need to do a conversion to another CMYK colour space. Or perhaps even back to RGB for re-purposing. So having keeping the Embedded Profile will again facilitate the most accurate conversions.
Why Do I recommend Convert to Working Space for Gray
There are not very many grayscale ICC profile’s in existance. Many of them are created by stripping out the CMY channels from CMYK profile and leaving just the black channel. We did this when we selected the GRACoL2006_Coated1v2.icc profile for our Gray Working Space. Nice practical feature that Photoshop has there. Grayscale is really only used for press output. So converting to the Gracol profile working space is perhaps a little more practical since GCR and Total Ink issues are non-existant for grayscale printing, but are more serious for full colour work. Besides it’s possible to convert to another grayscale profile later, as long as you save the profile with your image.
Why all the notifications
Well basically so that you can make the right decision for each colour managed situation you face. I’ll be covering that in the next post!
OK, there are going to be some people who may not agree with my recommendations here since you can’t please everyone. Once people work a certain way, they can be adament that any other way is completely ridiculous. For example, some people hate Quark Xpress, because they’re so used to Indesign as a publishing system. (personally I’m used to Indesign so I prefer it). And Quark Xpress veterans can sometimes hate Indesign - because it’s not Quark Xpress.
But I’m offering up this as a recommendation on how to setup your colour management in Adobe CS3 applications for professional print production. (Designing for print)
Note: You can decide to run with the default Adobe settings if you prefer. It’s not the end of the world if you do. Again this is just my recommendations. I will start with Photoshop CS3’s settings because there are more settings involved with Photoshop.
Photoshop CS3 Colour Space Settings
Photoshop CS3 Colour Management Policies
Photoshop CS3 Conversion Options
Advanced Controls
Now to see what it looks like in Photoshop, I’ve included a screen shot below.
Why Adobe RGB (1998)
RGB colour spaces are almost always larger than a destination CMYK colour space. That means the RGB colour space can produce more colour than the CMYK colour space. Since CMYK is the Destination, this poses a problem. What about the colours which are outside CMYK Colour space? Well they have to be shifted in one way or another. Shifted to the closest colour in the CMYK color space. This means that two separate blues in your RGB file, now look the same once converted to CMYK. The larger the RGB space & Smaller the CMYK space the more noticeable the effect is. The colours that are most effected a the pure Red, Green & Blues. The vibrant colours suffer the most.
Adobe RGB (1998) is not too big for an RGB space. This means it reduces the effect of the colour shifting
when converting from RGB to CMYK. This is a good thing for print production. Now the other good thing about Adobe RGB (1998) is that it’s balanced well. It doesn’t over-perform in the Red or the Green more than the blue. Vice Versa. That means no one RGB primary (red, green or blue) is going to ’suffer’ any more than the others. So that’s why Adobe RGB (1998) is commonly used in print production workflows.
Why GRACoL2006_Coated1v2 as the CMYK Profile
The GRACoL profile was created from a series of press runs done on multiple printers sites (as is normal for any standard profile). The presses were run and the press sheet was calibrated based on a new methodology for achieving an established international print standard. Basically it’s the print standard that is gaining the most popularity since it is easier to understand and implement for printers. So I suggest using this profile since it’s based on that standard. More likely to be relevant to more printers for the best result.
Why load the GRACoL2006_Coated1v2 under the Gray Working Space
The reason we do this, is that grayscale is basically just the black channel out of CMYK. (The ‘K’). If more printers are likely to be running to the Graycol standard than this will relevant for their black Work.
Why run 30% dotgain for Spot Working Space?
Spot colours are a different beast altogether. These are custom mixed inks, but still to a standard. However different ink manufacturers have different strength pigments. Also, sometimes mixing the ink by hand by the printer is not as stiff as if it has been pre-mixed by the ink manufacturer. In my experience printers have to run a thicker film of ink in order to get the correct spot colour match. This increase the amount of dotgain and results in screens getting darker. So I put a nice large dotgain value of 30% to compensate for that gain.
This might not be that relevant to all our visitors, but this post has a link below with an MP3 attached of me lecturing on Colour Management. Mainly talking about how profile to profile conversions work. Why do we need to do CMYK>CMYK Conversions. Recommendations on how to set up your colour management settings in Adobe CS3 and what to do when you get Colour Profile warnings from Photoshop.
For students who need to go over what I’ve said, it may be helpful. (That is if you can stand listen to me a second time : )
Oh sorry about the ‘ruffling’ sound. It’s the MP3 recorder moving in my shirt pocket. I’ll look into getting a clip of some sort for the next lectures.
Pratical Colour Management MP3 (includes ramblings)
This is a 77 MB file and it’s an hour and a half long.
Rest of the afternoon’s lecture.mp3
This one is 57 MB MP3 file and it’s just over an hour long.
I always believe it’s important for people involved in the printing industry to understand basic colour theory. So I am writing this blog post as a resource to some really great sites which will help any one interested in learning about colour theory. Some friends from the printplanet.com forum have helped me with tracking down some really great sites and downloads. So many thanks to those guys!
Just a little bit to start you off with…
Yes it really does sound impressive doesn’t it? I’ve been telling my friends and peers about it all week. Ha ha. I’m sure they’re getting sick of me telling them.
Well it’s something different anyway. I’ll be teaching a classroom of 8 design students how to prepare their files for commercial print production. I’ve got 8 sessions to teach, each being 3 hour stints per lesson. This is spread out over 8 weeks. So one lesson per week. That’s not much to attempt to teach a 4 year trade to completely new students.
So it’s going to be a challenge. I’m going to need to teach in a very fast paced, condensed manner which means I need to make every bullet count. This in turn is forcing me to dig deeper into industry resources to find out the absolute best practices available and teach them that. The best theory resources which cover the most relevant issues.
So it’s forcing me to sharpen up a bit and get my teaching/lecturing skills honed. Of course this is probably one of the most boring blog posts you’ve ever read, but it’s just an update on what’s happening.
I’d like to crack open our fresh new blog with a little exciting news. Your business cards don’t have to be boring! Yes that’s right. You can get some seriously funky business cards on our site.
We’ve been working tirelessly day (and night - believe me) getting some really cool business card templates up on our site and attaching some pretty ‘out-there’, ‘insano’ images to them.
Man you can have some fun with it! In fact Lyn Hollands posted the other day, how much fun she was having creating customers business cards with the new system!
One particular visitor had so much fun she emailed us and said, “That was the best 5 hours of my life”. I was kinda concerned that she was having difficulties with the site but she said, “No no, there was so much to choose from, I just kept experimenting”.
So it’s cool to see that a few people are excited about it. So YOU don’t have to have boring old business cards any longer!
Just click here to start experimenting with funky business cards! woo hoo! Have fun!
