Top 5 Printmaking Tips,Tricks,Techniques – June ’11(from Breathingcolor.com)
By Paul Morales on Jul 01, 2011 11:44 am
In this article we will discuss the most frequently asked questions when troubleshooting prints that did not come out properly. If your print has head strikes, banding, or inaccurate color look here…
1. My last print has head strikes. What caused this to happen and how can it be avoided?
Head strikes- When the print-head comes into contact with the media being printed. This appears as smeared ink in a particular spot on the print. Head strikes can be caused by several things. To understand what a head strike is, let’s first address what causes this to happen. If the head height (or platen gap) is not set properly to accommodate thicker media, this could cause a head strike. If there is a strong curl to the media you are printing on, this could also cause a head strike as the media surface may be raised inside the printer. Though more common on a solvent printer, if the media is not loaded correctly the pinch rollers can cause the media to skew or create waves in the media. These waves could come in contact with the print-head causing a head strike. To combat these issues, a simply approach can be made to avoid/eliminate head strikes:
- Check the thickness of your media and raise the platen gap/head height accordingly.
- If the media has a strong curl to it, feed the first few inches to avoid the curled leading edge.
- On a solvent printer, be sure to adjust the heaters according to the needs of the media. Too much heat in the earlier stages of the print may cause the media to buckle. This is especially true with adhesive vinyl and heat sensitive materials.
2. My black and white prints have a Magenta/Cyan cast. How can I fix this?
Usually when this happens it is assumed that the ICC profile being used is not accurate. Sometimes this is the case. But in other cases you could have missing nozzles in the print-head. With regular printing and down time (without any cleaning procedures completed), every printer will get clogged nozzles over time. In some cases, you may have an entire channel clogged and therefore not printing. This would absolutely cause a color shift on your prints as black typically is printed with a process (using Cyan, Magenta, Yellow and Black ink versus only Black ink). If all of your nozzles are firing and you’re sure that you have a working profile, check the file in Photoshop. If you see the cast on screen you can convert the file to grayscale and save a copy. This eliminates the color values in the file and allows the profile to interpret everything in the image as black or shades of black. If you still see a color cast, chances are you may need a new ICC profile. It’s always good to calibrate your printer and insure a perfect nozzle check before creating a profile as this will insure accurate output from the profile.
3. My print shows visible banding. How can I get rid of it?
Banding- When print head passes don’t line up properly and create lines in the print. When the passes overlap this creates dark lines. When there is a gap between the passes this creates white lines. There are 3 main types of banding that one might see in a print. Most people refer to lines in the print as banding. But the appearance of the lines will tell you not only what is causing the banding but also how to fix it. First off, these lines typically appear left to right when standing in front of the printer. Dark lines or white lines are caused by inaccurate feeding of the media being loaded. A standard print-head pass covers 1 inch (8 pass=8 print-head passes to cover 1 inch of media). If the media is not fed properly the head passes could be overlapping each other or be too wide to line up properly. When the passes are overlapping, this causes dark lines going across the media. When the passes have a gap between them, you will see white lines in the print. This is actually an absence of color! To adjust this quickly and easily, run a feed adjustment on your printer. This function comes standard on almost every Epson, Canon and HP printer and is typically performed on the printer console itself. Missing nozzle- A nozzle that is clogged and not firing. Deflecting nozzle- A nozzle that is firing but not at the correct angle. A deflection can be created by a partially clogged nozzle that affects the angle of the ink being fired. One other cause for banding has actually been described above: missing nozzles. But deflecting nozzles can also cause banding. Most nozzle prints are in a stair-step pattern when looking at each individual nozzle. Any nozzles you see that are firing but out of this pattern are deflecting. A light cleaning will normally take care of this, but if you find multiple deflecting nozzles in one color (and a cleaning does not correct them) run a small print with a solid color that best represents the nozzles in question. For example, this is most common in the black ink channels so run a small print of solid black and this should correct the firing of the nozzles. This type of banding is usually only noticeable in 1 particular color (dark areas caused by black deflecting nozzles; a red area could be a combination of Magenta and/or Yellow). Examine your prints closely (or with a loupe/magnifier) and you can correct these issues once they arise.
4. My print has noticeable ink artifacts in certain colors. How can I adjust this?
Ink artifacts- Any un-natural color output including: patches of color appearing blotchy; ink pooling; over-saturated tones and highlights; and blown out areas. These issues are usually caused by an excess of ink saturation. Each media you print on has a certain amount of ink that it can handle before there is too much. Various ink artifacts are most noticeable in solid colors. The green swatch above shows ink pooling in the weaves of the canvas. Be sure to use an appropriate media type that outputs only the necessary amount of ink for the particular media. If there is no media type that handles this perfectly, experiment with adjusting the Color Density (for Epson). Lowering the color density will effectively lower the overall ink load until you have a setting that works. This setting can be found under the Paper Configuration window in the Epson driver.
5. My print has lost detail in shadows and dark areas. How can I fix this?
If you notice a loss (or lack of) detail in shadow areas or dark areas of your print, first make sure that you have the proper ink load applied (see above tips). If the media settings are good, it may be time to get a new profile. The ICC profile controls how color is output, but it will also smooth out gradients, brighten up darker areas and tone down lighter areas of the print. At Breathing Color we offer free custom ICC profiling for all of our products. If the existing profiles you have are no longer giving you the results you need, or you just purchased a new product and want a profile, give us a call today and we can take care of it! If any of the above tips remind you of an issue you’ve ran into with your prints, please post a comment below.
Learn From The Experts: Marcus Bell <http://nikimedia.us2.list-manage1.com/track/click?u=973c9f54da7cd1ec2f2b76d47&id=49f0e7e0f4&e=4375497794>
Top 5 Printmaking Tips,Tricks,Techniques – May ’11 <http://nikimedia.us2.list-manage.com/track/click?u=973c9f54da7cd1ec2f2b76d47&id=229c7c8cd9&e=4375497794>
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Learn From The Experts: Michael Gilbert <http://nikimedia.us2.list-manage.com/track/click?u=973c9f54da7cd1ec2f2b76d47&id=39bb2f5ed5&e=4375497794>
Padded Cores for Canvas Rolls: You asked, we listened. <http://nikimedia.us2.list-manage.com/track/click?u=973c9f54da7cd1ec2f2b76d47&id=74c726b48b&e=4375497794>