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1. Re: Very basic question on CMYK percentages and the printed output
Mike Gondek2 Jun 20, 2011 8:35 AM (in response to TCarp)Every output device will print differently. You can even output to the same exact device a week alter and get different output, because any factors that chaneg such as humidity, temperature can also affect the color.
If you have control over choosing colors, than using solid colors rather than screened percentages can give you more color consistency. A 100k background color would look more similar than a 50%k background across multiple output devices.
Color profiling can get you more consistent color, but that requires hardware (Spectraphotometer) to scan a test print, and generate a color profile that you attach to your files.
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2. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 20, 2011 9:18 AM (in response to Mike Gondek2)I'm not looking for getting color consistency from day to day as much as I want to understand what habit to get into so what I print on my home laser is reasonably close to what I'll get at the office supply shop. Or, perhaps better, is to get a color sample page(s) printed at the copier/printer so I have it as reference.
I'm assuming "solid" means 100% for C, M, Y, and K. Sounds like 8 choices which seems pretty limited.
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3. Re: Very basic question on CMYK percentages and the printed output
emil emil Jun 20, 2011 10:18 AM (in response to TCarp)No, solid means one can of ink will be used for printing instead of four inks Cyan, Magenta, Yellow, and Black. Solid or in other word spot color will print more consistently using different presses and media because the perfect mixture of four colors is not always so perfect while using one ink rules out mixing imperfections.
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4. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 20, 2011 10:44 AM (in response to TCarp)Your 'very basic question' breaches on a huge subject. In fact it's not basic at all.
Your laser printer can give similar colour results to offset on semi matte white stock but there's no reason to suppose that it will unless everything has been very carefully calibrated. For example what looks good at your end may look terrible when it's printed on newsprint. Under normal circumstances you will need different colour setups and colour profiles for different paper stock. The two processes (office laser and offset printing) are so dissimilar that you must learn a lot about printing and colour separating to be able to get things right. These days many printing works prefer to do their own colour separating, so picture files especially should be delivered in RGB. My advice to you is to work in close co-operation with your printer whenever possible. If you're not sure about something, ask. Never trust your in-house laser for accurate results.
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5. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 20, 2011 12:50 PM (in response to Steve Fairbairn)Steve
I'm very much aware of the depth of this subject. I've gained an appreciation for its complexity as I've dabbled in it over the years.
The target printer is not offset. There won't be anywhere near enough volume to justify. I'm assuming the output will be to laser. I don't have the capability at home to print on paper greater than legal so need a place that can. Perhaps these places are called "copy centers" so I'm assuming they take my PDF files (or whatever format they accept) and send them to the laser printer portion of a high-end copy machine. I've had them run one set to see the color and clarity as a start.
I'm going to meet with them again this week. The last time we talked he mentioned their equipment has "vector" capabilities and, since much of the output is vector, I'll figure out how best to align to their capabilities. Although the map output will come from a GIS tool, the color "learning" will, I assume, apply to AI.
I'll be interested to see the differewnces in color between my home laser and what the copy center produces.
Do the cautions on spot color change knowing the output is intended for laser?
Tom
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6. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 20, 2011 2:20 PM (in response to TCarp)If you are not going to print with offset, spot colours are out of the question.
The best you can do is to compare the two laser printers carefully. Print out a colour scale from your machine and compare it with a printout of the same scale from the commercial machine. Following that you will either have to recalibrate your own machine to match the commercial machine (or vice versa if the commercial guy can be persuaded to change his settings).
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7. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 20, 2011 8:09 PM (in response to Steve Fairbairn)Thanks Steve
In fact it will be somewhat easier than that. I'm not trying to get the colours ("colors" for us colonists) of my laser and the copy center laser to match. I'll adapt the color scheme used in the maps and AI documents to that of the center.
Am I correct in assuming these devices can print our their color palettes? I'll take a look at my user manual.
This may be the recommendation I was looking for behind my original question.
Tom
[EDIT] Maybe I'm getting closer to know the right question to ask.
Are there concerns like there are/were about web-friendly RGB colors for CMYK? Or, do I just select a color scheme I like, code the CMYK in the app, and then test how it looks on the laser printer? Or, do laser printers have a set of CMYK color codes it "prefers" or produces better?
Another thought is to put together a CMYK color wheel, print it on the target laser, and then select the colors (and scheme) I like? Since there are a whole bunch of CMYK combinations, is there a good subset to put in a color wheel for testing?
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8. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 21, 2011 2:34 AM (in response to TCarp)At last we have a colonist who admits to being one! I don't trust myself to write colonial English consistantly which is why I keep to the other version :-)
Yes, I think most lasers can print out their own colour palettes. All the same I think it is probably best if you make your own test sheet to get an accurate comparison.
In my experience it is usually the very faint and very dark ends of the colour scales that have the most discrepancy between machines.
So make a scale of each colour (C,M,Y,K) with 5% increments.
You might also try a smooth gradient of each colour from 0% to 100% so that you can see whether the printer produces any significant banding or steps.
You can expect a step at the dark end of the scale where the dots squash into each other and you need to know where the breakoff point at the light end is.
It may also be necessary to make colour scales running both vertically and horizontally. Some machines produce varying results depending on the direction the paper goes through the machine. This shouldn't happen but sometimes does.
The question about RGB is probably irrelevant for a laser (though not so for an ink jet). At any rate you definitely don't need to bother about web-safe colours – they are only for screen use, not print, conceived originally for people who only had a 256-colour monitor. Such folks are difficult to find these days :-)
Your test sheet might look something like this:
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9. Re: Very basic question on CMYK percentages and the printed output
John Danek Jun 21, 2011 6:47 AM (in response to TCarp)This is a very technical issue. I'll give you my take on it. But, basicly, if you are not in a demanding color environment ( which you are not ), then you can get away with using this formula: 20-40-60-80-100 in all CMYK percentages. Trouble arises when you delegate colors below 20% and above 80%. Some lasers and paper combinations may have difficulty with below 30 and above 70. This all depends on life of the printer, its resolution, and paper used.
"Obviously, I can set the CMYK combination to any % for each color in both GIS and AI. Are there some percentages or combinations that work better than others or will they all print well? I'm not askiing a color scheme question, but more of a technical one."
As posted above, some printers are mated with Postcript 3 RIP's and multiple color cartridges ( i.e., Epson 3880, HP Designjet 130 ) in order to be able to print low and high percentages. Your average document printer cannot match their gamut.
"For example, I have a color laser at home. Will it differentiate between c=24% and c=25% (even if my eye couldn't)? Will I get the same visual using c-37%, m=44%, y=79% and k=62% on my home laser as I will on the production printer (at my local office supply store)?"
Those percentages are mid to upper mid range and should print similarly. Laser's cannot match inkjet's ability to print color more believably. Now, you are talking about a 1% deviation between a 24% and a 25%. At that range, the printer will probably be able to print the 1% difference, but it is undetechable and renders the discussion moot. Is it an accurate 1% or is it .885%, or is it 1.3125%? Only a densitometer would be able to tell.
"For now I'm assuming I can use any CMYK formula I want. I'm also assuming (although I don't know why) that the printed output will/can look different on different printers (my home laser, my local Staples or Kinko). This means I do the final color correction at the print store.
Am I headed in the right direction in my thinking?"
Even the Kinko's guy does not know the percentages his printer can reproduce and which it cannot. You're thinking is somewhat correct. However, I would work inside your biggest limitations ( i.e., prep for the laser ). Then, you will be cutting your work in half. If, at some point, you can open the checkbook and drop $1400.00 for an Epson Pro 3880 ( 17x22" ) Graphic Arts Edition ( with the Efi XPress RIP, then you can prep for a wider gamut that can be matched anywhere ( a similar printer is used ).
Tom
"[EDIT] After some more reading it appears my assumption that I can use any % and still expect no print issues is not right. One web article shows the color picker can indicate a color that is "out of gamut" which apparently means it can't be printed exactly as specified. Since I'm new to the terminology, I must admit I thought the gamut was specific to a device. How would AI know anything about the equipment being used for the final print (other than the printer setting I have in my pc)? Time to read more about gamut."
Yes, much reading to do. Unfortunately, there are colors that are difficult to print. I'm not going to confuse the issue with Spot color generation. Many claims about printer resolution are not true. The inkjet device is only capable of printing a certain resolution based on print head technology. Hence, there is an inherent limitation on output gamut. However, to compensate for certain limitations, printers expanded their color cartridges to compensate and open the gamut up a bit more. Like I said at the beginning, you're asking a very technical question eventhough it seems basic in nature.
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10. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 21, 2011 8:25 AM (in response to Steve Fairbairn)Thanks John and Steve
(Steve, admitting to be a Colonist puts you in charge doesn't it? I could use a break from being the big kid on the block.)
Between the two of you and your posts I've advanced my understand enough to take the next steps. I'd built a color sample page some time ago for my inkjet printer and web work (Visibone inspired). I'd actually started building something similar for CMYK. It's based on the Pantone color bridge that contains a bit over 1,100 colors (of the 100 million possible CMYK) combinations. For the short term, I'll follow your advice and build a 5% increment color sheet with some color ramps to augment.
I'll probably have more questions after I work with the copy center.
Tom
P.S. Although my RGB comment was only an analogy, I need to think as to why its relevant for injets (which I also have at home). I haven;t had need to change the color cartridges for some time since the laser is now my default printer. It may be the printer used RGB cartridges. Your comment is also interesting about the difference in vividness between the laser and inkjet. My only problem with the inkjet (other than ink cost) was that the ink smeared.
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11. Re: Very basic question on CMYK percentages and the printed output
emil emil Jun 21, 2011 10:26 AM (in response to TCarp)Color management was designed to address exactly issues like this but if you don't have it in place, in your situation I'm not sure if you can afford it because I don't think at places like Kinko they color profile their printers. But in ideal situation or if you find a place where they do, this is how it works - using a color measuring device like colorimeter or spectrophotometer, you calibrate your monitor to a known state and then create a color profile that describes how your monitor displays color values. Using a printed color measuring device like spectrophotometer, the end device (printer) is calibrated and color profiled. You obtain the color profile of the printer and assign it to your document in Illustrator. With your monitor color profile installed in the System, Illustrator will simulate on your monitor how the end device (printer) reproduces colors. So you can choose colors limited to the color space overlapped by both the printer and your monitor or if you choose colors outside of the target color space they will be converted to the closest equivalent using rendering intends specified by the user.
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12. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 21, 2011 10:40 AM (in response to TCarp)P.S. Although my RGB comment was only an analogy, I need to think as to why its relevant for injets (which I also have at home). I haven;t had need to change the color cartridges for some time since the laser is now my default printer. It may be the printer used RGB cartridges. Your comment is also interesting about the difference in vividness between the laser and inkjet. My only problem with the inkjet (other than ink cost) was that the ink smeared.
The point is that inkjet printers work better with RGB input. They translate RGB to CMYK with their own built-in software. Sometimes they don't even print with CMYK but use in-between colours as well. Some have 6 or more ink cartridges. A CMYK file wil tend to be dull on an inkjet because the colours need to be translated to RGB and then back again to the printer's CMYK-or-wotever. If the colour range (gamut) isn't there in the first place you can't expect an inkjet to invent what you think ought to be there.
Laser printers on the other hand use CMYK ink powder and a heat unit for melting it onto the paper (same as with a photocopier). The ones I have used have PostScript software. This means basically that CMYK is better for input than RGB because the colours don't need to be translated. So the colour percentages in your CMYK artwork should print correctly if the machine is correctly calibrated.
The CMYK gamut is considerably narrower than the RGB gamut, so you can expect loss of intensity compared with RGB. See what happens when you change a brightly coloured image from RGB to CMYK in Photoshop. There are a lot of colours that simply can't be reproduced satisfactorily in CMYK. But if your artwork is already in CMYK you don't have to worry. Read more about this on sites like http://dx.sheridan.com/advisor/cmyk_color.html
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13. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 22, 2011 6:43 AM (in response to emil emil)Thanks for the post. Color management is certainly a "black hole". I can imagine that it's a huge deal to professionals. My needs have considerably less ramifications.
Tom
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14. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 22, 2011 6:50 AM (in response to Steve Fairbairn)That explains it very well. My inkjet has 6 cartridges. It's actually a photo printer and does an incredible job when printing photos on photo paper.
It would be nice to be able to fix the ink somehow although my needs are driven more by the paper size. The cheapest alternative for the volume I have appears to be copy centers which means laser.
I've actually created a color sample sheet like the one you recommended. I'll run it on my laser (and inkjet) just to see the differences. The real run will be when I have the copy center print it. Since I'm not looking for exact color matching, it will probably be enough for now.
BTW, thanks for the link. One of the reasons I post in the Adobe forums is because the participants are so helpful for an amateur like me.
Tom
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15. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 22, 2011 10:17 AM (in response to TCarp)Pleased to be of assistance :-)
The information I gave you is of course very sketchy, just to give you an idea of what you are up against.
Colour management is far too vast a subject for a forum like this, so do any reading you can.
Oh yes, and one thing I forgot to mention: If your computer asks if you want to "Embed ICC Profiles" the rule of thumb is YES for RGB files and NO for CMYK files.
Colour profiles are really only useful if you need colour consistancy when translating RGB files to CMYK.
If they are embedded in CMYK files they can have adverse effects on how the Rip (Raster Image Processor) defines the colours. An embedded profile might cause a colour cast (depending on the rip). The first time I saw such a cast I spent a lot of time tracking down the culprit, and it turned out it was indeed an embedded profile.
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16. Re: Very basic question on CMYK percentages and the printed output
medicineheads.no Jun 22, 2011 11:19 AM (in response to TCarp)Just to be on the safe side, be sure your document is in the chosen color space.
>file >Document Color Mode >CMYK of RGB. Set to RGB you can write all the CMYK values you want - but they will be "translated" back to RGB color space and visa versa.
- I don't think this was mentioned.
Will I get the same visual using c-37%, m=44%, y=79% and k=62% on my home laser as I will on the production printer (at my local office supply store)?
Another thing which is intrinsic in these postings, the reason the colors will vary, is that even printed on different color lasers with CMYK "inks" it may not be the same type or manufacturer of those inks. Hence there are at least three large standards for the printing press: American, European and Japan CMYK. And two (or more?) large companies working with colormatching in printing, Pantone for the western world and Toyo for Asia.
Then there are the companies making ink for desktop/professional printers, and the companies making inexpensive replacement cartridges for those machines.
A Rose is a Rose is a Rose - except in color.
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17. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 22, 2011 2:24 PM (in response to medicineheads.no)Another thing which is intrinsic in these postings, the reason the colors will vary, is that even printed on different color lasers with CMYK "inks" it may not be the same type or manufacturer of those inks. Hence there are at least three large standards for the printing press: American, European and Japan CMYK. And two (or more?) large companies working with colormatching in printing, Pantone for the western world and Toyo for Asia.
Very good point.
A Rose is a Rose is a Rose - except in color.
The trick is to Think Pink and keep your eyes open :-)
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18. Re: Very basic question on CMYK percentages and the printed output
Larry G. Schneider Jun 22, 2011 3:25 PM (in response to Steve Fairbairn)Most easily done with "Rose" colored glasses.
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19. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 23, 2011 7:17 AM (in response to Steve Fairbairn)So am I to assume as a simple "colonist" that the more complex the topic the greater the chance of humour (humor)?
I've just taken a class on GIS. Now there's a group of folk with a need for a joke or two (or a lot more) to maintain sanity.
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20. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 23, 2011 7:46 AM (in response to TCarp)Yep. Some of these threads tend to get wildly sidetracked. Here's one:
http://forums.adobe.com/message/3666724#3666724
Frequent posters get to know each others' quirks quite well.
In this one Jacob's in Denmark, Peter (who calls himself tromboniator 'cos he plays the fiddle or something) is in Alaska and I'm an ex-Brit working these past 40 years or so in Iceland of all places.
So now we just have to work out which of us are the colonials, which are the backwoodsmen and which are the imperialists.
Funny old world :-)
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21. Re: Very basic question on CMYK percentages and the printed output
Wade_Zimmerman Jun 23, 2011 8:27 AM (in response to Steve Fairbairn)steve fairbairn wrote:
Pleased to be of assistance :-)
The information I gave you is of course very sketchy, just to give you an idea of what you are up against.
Colour management is far too vast a subject for a forum like this, so do any reading you can.
Oh yes, and one thing I forgot to mention: If your computer asks if you want to "Embed ICC Profiles" the rule of thumb is YES for RGB files and NO for CMYK files.
Colour profiles are really only useful if you need colour consistancy when translating RGB files to CMYK.
If they are embedded in CMYK files they can have adverse effects on how the Rip (Raster Image Processor) defines the colours. An embedded profile might cause a colour cast (depending on the rip). The first time I saw such a cast I spent a lot of time tracking down the culprit, and it turned out it was indeed an embedded profile.
Not entirely true, eventually the file will have a profile assigned to it when the printer sends it to the imagesetter to make the negative and if they give you their profile then you use and embed that profile. If you adjust the color and it is different from their profile and they convert then there may be a difference since you did not embed the profile they will not know. So the best policy is to obtain the profile from the printer and send them the cmyk file with their profile embedded. Unless of course the printer says not to do this and of course if you are working with spot colors then then there is no profile.
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22. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 23, 2011 8:58 AM (in response to Wade_Zimmerman)Yep Wade, I know, but I didn't want to complicate the issue for the purpose of this discussion which is based on Illustrator output.
Omitting embedded profiles in CMYK files is the general rule all the same, at least in my neck of the woods.
The thing is that in an increasing number of countries, printing companies prefer to make their own colour separations.
In this country (Iceland) it's over 90% of printing firms.
We send final artwork in the form of pdfs from InDesign (not Illie) with CMYK graphics and RGB images. We have been advised not to make the pdfs straight from Illie because once you embed images in Illie they take on the same colour gamut as the file itself. Linked images don't work properly and usually split up during the pdf-ing process, leaving visible (and printable) horizontal white lines through them. This has caused endless trouble at the printers and a lot of extra work at the artwork end. Using InDesign you can make satisfactory pdfs without embedding the images, and no white lines.
I'm on Illie CS3 but as far as I know (correct me if I'm wrong) this issue has not been addressed in CS5, so it's still a problem.
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23. Re: Very basic question on CMYK percentages and the printed output
Wade_Zimmerman Jun 23, 2011 9:19 AM (in response to Steve Fairbairn)You are correct!
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24. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 23, 2011 2:52 PM (in response to Steve Fairbairn)Just wanted to let you know I got a print of the color samples at the copy center today on all the 11x17 papers they use. This means I now have a good sample that, even with some variations that would occur on that laser from day-to-day, it's close enough for what I'm doing.
An interesting wrinkle: although 99% of the print outputs will be on the laser, a couple will be also plotted which, in the case of the copy center, is inkjet. Good that I learned that there would be differences in color between laser and inkjet. When the time comes to plot, I'll get a color sample from it and do any color correction I need.
Nice to have both a laser and inkjet at home to run some comparisons.
Tom
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25. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 23, 2011 3:14 PM (in response to TCarp)Glad things are working out for you.
Get them to print your test sheet on their inkjet and you'll see how much difference there is.
What you call a plotter I call a commercial inkjet (they usually have 6 print heads and prefer RGB input).
Maybe yours is colonial terminology?
To my way of thinking a plotter is a gadget that draws with a pen using x-y co-ordinates and a mechanism somewhat resembling that of an old-fashioned drawing board like we used to use in those pre-computer days of cut fingers and rotring pens with nosebleeds.
Modern plotters are also used to cut out self adhesive vinyl, in which case the roll of material is pulled back and forth between rollers and the knife moves from side to side.
Not that it matters.
The funny thing about this job is that the more you know, the more you discover there is to learn.
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26. Re: Very basic question on CMYK percentages and the printed output
Jacob Bugge Jun 24, 2011 8:18 AM (in response to TCarp)TCarp, Steve, others,
A very nice, long thread.
Over the latest days I have tried to get it read, but never succeeded until now, owing to my trying to get to the last ragwort standing.
Peter has not read it (in full) yet.
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27. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 24, 2011 10:28 AM (in response to Jacob Bugge)Although I take far more than I give to these forums, it's always my intent to leave a trail of learning for those who may not have the experience (like me) that many of you do.
For me, as a non-professional, sometimes its just figuring out the question and the Adobe forums I've posted to have a lot of patient parties willing to post. Over the years I've learned a great deal in forums like AI, IL, Acrobat, Photoshop, and DW just to name a few.
Tom
[EDIT] In the spirit of learning, let me list some of the "gems" I got from this thread (again for a non-professional).
Create a color sample page and get it printed on the target print devices.
Recogninze that there will be variations when things change (like the paper being used) so test as many variables as possible. I saw this when I went in for my most recent print test when I asked they print on all 11x17 papers they would normally have available. Even little bits of "sheen" differences cause some colors to shift.
Laser and inkjet will produce different color results and what some of us call (perhaps inaccurately) a "plotter" can be a large inkjet printer
If I think of more I'll do another edit.
Tom
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28. Re: Very basic question on CMYK percentages and the printed output
TCarp Jun 24, 2011 10:34 AM (in response to Steve Fairbairn)Thanks for challenging my use of the word "plotter". I don't think this is colony-speak, just laziness on my part.
I'm not sure I can describe a plotter (ala Boeing Engineer use for example). What I saw available at my copy center might better be described as a large media inkjet. The technician even opened the ink cartridge area on the device and, like my home inkjet, it has 6 color cartridges. When I realized that it was an inkjet, I asked the question most important to me which was "does the ink risk smearing". The answer, of course, was yes. He even ran one of my laser outputs through a 3-mil laminator so I could see what laminating would do (i.e. how stiff) knowing that I may want to laminate the "plots" when done. Since only a very small fraction of the maps being produced I'll want on large media, it will be something I just need to include in the workflow (and budget).
Tom
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29. Re: Very basic question on CMYK percentages and the printed output
Steve Fairbairn Jun 24, 2011 12:01 PM (in response to TCarp)"does the ink risk smearing". The answer, of course, was yes.
Yes, because ink jet inks are water based.
You must never touch a newly printed sheet, especially if the substrate is shiny.
Always laminate.
I've done a lot of exhibition display work.
Once the printer forgot to laminate a panel and the whole thing was ruined while the guys were hanging the stuff up.
The exhibition was in China, so there was no way of getting things put to rights before the opening.
The customer got a discount at the printer's expense.





