Colour matching

Colour matching

Colour matching

If colour is critical, please provide a proof for us to match to, and ask for a hard copy proof. We ALWAYS recommend that clients provide proofs to match if colour is critical, and recommend that clients with colour critical job ask for a hard copy proof.

In some 20 years of pre-press we have never relied on what is shown on screen. We have owned $40,000 calibrated monitors in the past and still have no faith in anything but a CMYK breakdown for matching specific colours. Even then you need to have an accurate printed reference to match to as well — such as a Pantone Process book. There are many Pantone Books available. Consider purchasing a ‘PANTONE color bridge coated’ book.

Digital prints are good and getting better all the time, but when it comes to calibration ‘out of the box’ with no operator intervention we have yet to see or use one that is truly accurate. Tweaking by an operator always seems to be needed. ‘I know my Epson printer at home tends to do this . . . ’ — enough said!

Skin-tones are the worst. A few percentage points of one ink in any direction can throw the cast off altogether.

Be aware that our presses are regularly calibrated to industry standards. We, along with most printers pride ourselves on producing quality, predictable, repeatable colour. From time to time however, customers are surprised that the colour they were expecting is not what they received. If colour fidelity is critical, a number of steps can be taken to increase your chances of getting exactly what you want.

1. If the job is colour critical, it is a very good idea to ask for hard copy proofs. We charge $50 for hard copy proofs. If the colour revealed by the proofs is not what you expected you can make adjustments to your files and resubmit them. You can then ask for another hard copy proof, or a PDF proof. We will not bind or apply any coating to hard copy proofs as the main purpose of a hard copy proof is to check colour. It is unnecessarily expensive to ask for a hard copy proof if your main concern is the accuracy of the text — you can print out a PDF proof, which will normally cost you nothing — for such purposes.

2. You can provide us with hard copy prints prints and ask us to match them. In most cases it is possible to tweak the colours on a press to match supplied art work. If it is not possible, then we will advise you. Supplying us with hard copy prints is perhaps the best way to ensure you get the colour you want.

3. You should always convert files to CMYK from RGB before sending us the files, then check to see if there is any colour shift when making the conversion. You can then go back into the CMYK file and make colour adjustments. For instance, you will sometimes find that deep blues have turned a little purple. You can go a long way towards fixing this in an image editing package such as Adobe PhotoShop. You can can open the image and reduce the amount of magenta, perhaps increase the amount of cyan a smidge, and maybe add some black to restore the depth of colour. When converting from RGB to CMYK, it is very important to use the correct colour profile in the conversion. If you are printing on coated gloss or satin paper, use the profile ‘Coated FOGRA27 (ISO 12647:2:2004)’. Do NOT use any Japanese, US, Uncoated, Newsprint or Web profiles.

4. Computer monitors should be calibrated. This is critical. It used to be a very expensive process, and possible only with hideously expensive monitors, but these days there are a few monitor calibration tools available that are not expensive. One of the best devices is a small piece of equipment called a Colormuki which will do a lot more than calibrate monitors. For instance, you can read the colour off a hard copy print and replicate the colours in your page layout software. Another inexpensive device, although not as capable, is the Pantone Hue PRO

One of the most common problems with uncalibrated monitors has to do with brightness. Most people run their monitors too bright. If an image appears correct on a monitor that is too bright, it will print darker than you expect. Another problem occurs when the contrast between light and dark in the monitor is too great. You might adjust a picture that appears correct on a very contrasty monitor, only to find it reproduces rather dull and flat, without the punch you were after. A calibrated monitor will overcome these problems.

5. When printing out proofs, you should not depend on an inkjet printer for colour accuracy unless you can calibrate it. The chances are your office printer will not have any calibration tools. Calibration is usually carried out by printing a calibration sheet supplied with the printer, and consisting of a great many colour patches. The patches are then read by a colour spectrophotometer connected to the printer, which compares what was printed with what should have been printed by a perfectly calibrated printer. Then any adjustments required are automatically made to the printer. Such facilities are available only on high end printers, and are quite expensive.

6. View your had copy proof in daylight conditions, not in yellow incandescent light. The lighting conditions under which you view your proof can make an amazing difference. Try this experiment. Open a file on your calibrated monitor and compare it with the printed product, printed from the file you are viewing. Firstly, compare the two in daylight viewing conditions, ideally in the middle of the day, ideally on a sunny day, and with the monitor reasonably close to a window with daylight pouring in. Then draw the blinds, turn on incandescent lights if you have them and repeat the process. You will find the printed product look darker and more yellow. If the printing company has done the job correctly, then the hard copy compared to the file viewed on the calibrated monitor under daylight conditions should be almost identical

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