Preparing your artwork to screen print.
There are three artwork techniques commonly used for this type of printing: Trap, Knockout and Overprint. The Trap technique is when the bottom color “bleeds” under the top color, ensuring no gaps are left from inaccurate printing of the second color (when the so-called “registration” between the colors is “off”).
Screen printing is not always an exact printing technique, especially when printing onto fabric surfaces; for this reason the Knockout technique is rarely used, as it relies on printing a color precisely in a gap left on the bottom color. The third technique, Overprint, is the easiest to achieve as the top color prints directly on top of the bottom color; often this produces a new color, as the top ink color is not always opaque.
SETTING UP YOUR FILES FOR LASER CUTTING
For us to laser cut your file we will need to be supplied with a vector file, it’s the only format the laser cutter recognises,
WHAT IS A VECTOR FILE?
A vector file is a graphics file that contains a vector image, rather than a raster, or bitmapped, image. Shapes and lines make up vector graphics, which are fully scalable images, while raster images are made of pixels and cannot be scaled up without going burry.
Vector files can be created in programs such a Adobe Illustrator, Corel Draw, Inkscape (free) or Autocad (+ lots more). There are lots of tutorials on the internet to show you how to use these programs.
CREATING YOUR VECTOR FILE
The first thing you should do is decide what material you want to cut your designs from, this will dictate your document size - (checkout our materials page for material sheet sizes). Set your file up to the sheet size your materials comes in. You don’t have to order a full sheet of designs, this is just the maxiumum size it can be (see betow for how to best setup your partial sheet).
Draw your design using red, black and blue (explained below) The laser cutter only accepts 3 colours from your files: black = etching, red = cutting and blue = vector etching. Any other colours supplied in files will be ignored.
http://onlinelasercutting.com.au/setting-up-your-file.html
Embossing is accomplished by applying pressure with male and female dies that fit together and squeeze the paper. The pressure will create a 3d raised effect.
You can emboss a logo, a large title or any shape you want. Embossing on a blank or colored surface is called "blind embossing". Embossing used with hot stamping or spot uv is also possible and creates a nice effect.
Important
Embossing involves a separate stage in the production process, after any varnishing and laminating. Because it requires a separate press run, the embossing can be a little bit offset with the printing area. Please keep that in mind when creating the artwork. It is not a good idea to emboss small text or small design element. You will get better results if you emboss bigger elements or if you do blind emboss.
Embossing will create a reversed mark on the back of the paper. If you want to avoid that, you may want to go with debossing.
SETTING UP FOR EMBOSSING.
Embossing is accomplished by applying pressure with male and female dies that fit together and squeeze the paper. The pressure will create a 3d raised effect.
You can emboss a logo, a large title or any shape you want. Embossing on a blank or colored surface is called "blind embossing". Embossing used with hot stamping or spot uv is also possible and creates a nice effect.
Important
Embossing involves a separate stage in the production process, after any varnishing and laminating. Because it requires a separate press run, the embossing can be a little bit offset with the printing area. Please keep that in mind when creating the artwork. It is not a good idea to emboss small text or small design element. You will get better results if you emboss bigger elements or if you do blind emboss.
Embossing will create a reversed mark on the back of the paper. If you want to avoid that, you may want to go with debossing.
How to setup files for embossing?
When you setup files for embossed business cards, you need to create a separate file called a mask file. This file will be used to determine where the embossing will appear. The mask file must be exported in CYMK and must contain only one color : 100% black (C:0, M:0, Y:0, K:100). The black area will represent the embossed shape.
WHAT COLOUR MODEL TO PRINT WITH?
ILLUSTRATOR
- Make certain you open any new document in CMYK color mode. Yes open in CMYK, don't switch to CMYK if you opened an RGB document by mistake. Many things in Illustrator are dependent upon the document color mode. The Swatches, symbols, graphic styles, brushes, are all built to match the Document Color Mode. Switching color modes mid-stream does not change these items. Only opening a document in the proper color mode generates library items in the proper color mode. If you have work in an RGB document and need to print it, Copy/Paste to a CMYK document and then adjust coloring as needed. Do not simply change the Document Color Mode.
- Turn on Overprint Preview in the view menu (if it isn't already on).
- Ensure Document Raster Effects setting (Effect Menu) is set to 300ppi
- Ensure all linked or embedded raster images are in CMYK format at 300ppi (as well as other Photoshop requirements)
- Ensure all blacks are accurate. Whether using rich black or greyscale black, ensure objects are correct. And for heaven's sake change the preferences to always display and always output blacksaccurately. I dislike Adobe's default settings. They are a recipe for error where print production is concerned in my opinion.
- Ensure you have proper bleeds for any full-artboard projects.
- If using spot colors and transparency, stop. Don't. If you need transparency, then convert all spots to CMYK otherwise don't use transparency (other than clipping and opacity masks).
- For Illustrator-only projects it can, at times, be beneficial to simply rasterize entire artboards and save as a CMYK .tiff. This depends greatly on the artwork. However with really complex vector illustrations it can ensure printing is correct. Obviously when doing this you loose any spot color so it's only an option when working with CMYK.
- While not required, using Global swatches for CMYK colors can be very helpful. You can double-click a Global swatch and change its color build to change all colors in the artwork. This only works with Global Swatches.
- Use the Flattener Preview to verify the artwork will flatten as expected. You may need to expand appearances or flatten pieces of art on some occasions. I just recently had to rasterize a masthead to assit a print provider in outputting it properly.
PHOTOSHOP
- In general, Photoshop merely requires you to ensure the document is the proper resolution and the color profile is correct. If you've calibrated your system properly there's traditionally little more to worry about for straight CMYK projects.
- If using filters or items which require RGB mode, then work in RGB and convert to CMYK as the final step before outputting the image. This step is dependent upon proper color settings.
- For 6 or 8 color, or any spot color project there can be other concerns depending upon inter-application workflows. For example, if you are using Spot colors in Photoshop and also using those same spot colors in Illustrator or Indesign, you'll want spot color channels in Photoshop. This is so upon output all spots are on the correct plates. I won't go into the creation of spot channels in Photoshop since, that in itself, is an entire topic.
- If taking a Spot channel Photoshop document to Illustrator, you need to use the DCS2 format when saving so Illustrator can properly read the spot channels. If going to Indesign from Photoshop, you can use .psd, .eps, .pdf, or .dcs2.
- There are other things which may need addressed - color correction of photos is a big one, especially photos containing people. However I feel that too is a topic unto itself. There are tricks, for example, people should generally have 3% more yellow in their skin tone than they do magenta. This prevents a "rosy" appearance for people.
- ensure you have proper bleeds for images.
INDESIGN
- Again ensure the preferences are set to always display and output blacks accurately
- Placed raster images should be 100% and not rotated within Indesign. If you need to rotate an image or scale it, then note the degree of alteration, go back to Photoshop and apply those alterations and reimport the image. For optimum output all placed raster images should not be scaled or rotated. In all fairness, this is one of those items that has some wiggle room. A minor adjustment probably won't cause any real issues. However large scaling and rotations of placed raster images can effect the output of those raster images.
- Turn on Overprint Preview in the view menu.
- Ensure you have proper bleeds for pages.
- Always a good idea to run Preflight before exporting to PDFx. This will show any missing fonts or RGB images or other issues.
- Do not use rich black for small "body copy" text. If body text is black, just use 100% K. (this would hold true for Illustrator as well if you are using that as a layout application with smaller text.)
http://graphicdesign.stackexchange.com/questions/16512/prepare-a-design-for-cmyk-printing
IMAGE RESOLUTION
Bitmap images contain a fixed number of pixels, usually measured in pixels per inch (ppi). An image with a high resolution contains more, and therefore smaller, pixels than an image of the same printed dimensions with a low resolution. For example, a 1‑inch‑by‑1‑inch image with a resolution of 72 ppi contains a total of 5184 pixels (72 pixels wide x 72 pixels high = 5184). The same 1‑inch‑by‑1‑inch image with a resolution of 300 ppi would contain a total of 90,000 pixels.
For imported bitmap images, image resolution is determined by the source file. For bitmap effects, you can specify a custom resolution. To determine the image resolution to use, consider the medium of final distribution for the image. The following guidelines can help you determine your requirements for image resolution:Commercial printing Commercial printing requires 150 to 300 ppi (or more) images, depending on the press (dpi) and screen frequency (lpi) you’re using; always consult your prepress service provider before making production decisions. Because commercial printing requires large, high-resolution images, which take more time to display while you’re working with them, you may want to use low-resolution versions for layout and then replace them with high-resolution versions at print time.
In Illustrator and InDesign, you can work with low resolution versions by using the Links panel. In InDesign you can choose either Typical or Fast Display from the View > Display Performance menu; in Illustrator you can choose View > Outline. Alternatively, if your service provider supports Open Prepress Interface (OPI), they may provide low-resolution images to you.
Desktop printing
IMAGE RESOLUTION
Bitmap images contain a fixed number of pixels, usually measured in pixels per inch (ppi). An image with a high resolution contains more, and therefore smaller, pixels than an image of the same printed dimensions with a low resolution. For example, a 1‑inch‑by‑1‑inch image with a resolution of 72 ppi contains a total of 5184 pixels (72 pixels wide x 72 pixels high = 5184). The same 1‑inch‑by‑1‑inch image with a resolution of 300 ppi would contain a total of 90,000 pixels.
For imported bitmap images, image resolution is determined by the source file. For bitmap effects, you can specify a custom resolution. To determine the image resolution to use, consider the medium of final distribution for the image. The following guidelines can help you determine your requirements for image resolution:Commercial printing Commercial printing requires 150 to 300 ppi (or more) images, depending on the press (dpi) and screen frequency (lpi) you’re using; always consult your prepress service provider before making production decisions. Because commercial printing requires large, high-resolution images, which take more time to display while you’re working with them, you may want to use low-resolution versions for layout and then replace them with high-resolution versions at print time.
In Illustrator and InDesign, you can work with low resolution versions by using the Links panel. In InDesign you can choose either Typical or Fast Display from the View > Display Performance menu; in Illustrator you can choose View > Outline. Alternatively, if your service provider supports Open Prepress Interface (OPI), they may provide low-resolution images to you.
Desktop printing
Desktop printing usually requires images within the range of 72 ppi (for photographs printed on a 300 ppi printer) to 150 ppi (for photographs printed on devices up to 1000 ppi). For line art (1‑bit images), make sure that the resolution of your graphics matches the resolution of the printer.
Web
Web
Web publishing Because online publishing generally requires images with pixel dimensions that fit the intended monitor, the images are usually less than 500 pixels wide and 400 pixels tall, to leave room for browser window controls or such layout elements as captions. Creating an original image at screen resolution—96 ppi for Windows–based images, and 72 ppi for Mac OS–based images—lets you see the image as it will likely appear when viewed from a typical web browser. When you’re publishing online, the only times you’re likely to need resolutions above those ranges are when you want viewers to be able to zoom in for more detail in a PDF document, or when you’re producing a document for printing on demand.
PRINTING ARTWORK
A composite is a single-page version of artwork that corresponds to what you see in the illustration window—in other words, a straightforward print job. Composites are also useful for proofing the overall page design, verifying image resolution, and identifying problems that may occur on an imagesetter (such as PostScript errors).
This last section i have researched about how to generally print something is pretty basic but i think it will be important to include in my print book for the preparation stage.
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