A raster image is made up of thousands of circles, and based on their size and proximity to one another the image can look like a full-picture without a large loss in quality. Black and white, monochrome, or full-color posters are possible, and the price is pretty cheap too. Aside from borrowing a paper-cutter, including all supplies, I made a full-color nine foot diagonal poster for $50, and a black & white one for $26. This project requires some patience and precision, it took me around four hours to produce the final poster used in this guide.
I hope you learn and have fun in following this instructable, and produce some really neat pieces of art!
Step 1: Supplies and Costs
This is the image that will become your new poster. Though it can be any size, for the best results, I recommend a size of at least 720 pixels wide. Though your image does not need to be simple, I advise against highly intricate pictures, since the rasterizing process loses fine-details.
The Rasterbator (Free)
The Windows program that takes your digital image and processes it into a rasterized Adobe PDF for printing.
White Poster Board ($2 per three 22"x28" boards at Michael's craft store)
In this guide, I needed five poster boards for my 6 1/2' poster, so $4.
Thumbdrive or CD-R ($Peanuts)
You likely already have these, or know someone who does. It only needs to hold a 10MB-100MB PDF file.
Spray Adhesive ($6)
It's glue in a spray-can. You may need to be 18 or older to purchase it.
Printing Service ($5-50)
I used Kinko's Office Print and Copy, which charges $0.53 per color page. Black and white is $0.12 per page. For the poster in this instructable, at 32 sheets, the cost was $17. Your printing service will print out the PDF from your thumbdrive or CD. Note that Kinko's is meant for office copies, and doesn't have very accurate color. Local print shops can produce higher quality images, though price varies.
Clear 3M Packaging Tape ($4)
Purchase the thicker tape if possible, it's easier to apply without bubbles or folds.
Paper Cutter and/or Scissors ($5-50)
The paper will not be printed directly to the edge (called full-bleed printing), and has a thin border about 1/8" from the edge of the paper. We will need to cut along this border for every page, so a paper-cutter is extremely helpful. Scissors can be used in isolation (though it takes much longer), and help clean up bad paper-cutter cuts. I borrowed one from a friend who is a high-school teacher.
For hanging the poster to the wall.
1/2" Grommet Kit ($9)
Used for making stamped holes in the poster, to better nail it to a wall.
Step 2: Rasterizing Instructions
2. Open Rasterbator stand-alone or the online-version, and you will be asked for your source image. Select your JPG image.
3. If you live in the United States, select "Standard Paper Size" US Letter (216x279mm). I suggest portait mode. Europe more often uses A4 sized paper.
4. Select the size of your image, a larger poster entails a higher cost and more work, though an immense poster can be very rewarding.
5. I suggest using a dot size of 3-4mm for anything fifteen feet and under, as this allows for more fine resolution and easier lining up of pages than the default size of 10mm. Generally, larger images use larger size dots, smaller images use smaller dots. Select Black (and White), Monochrome (Custom Color), or Full-color (Multi-color) by your preference.
6. Check "Draw Cutout Line" as we will need it to line up our pages properly.
7. Select Rasterbate to produce your rasterized PDF file.
Step 3: Printing
Step 4: Trimming the Pages
Some tips for the paper cutter.
1. Cut slowly to prevent ruining a page. If one page is destroyed, it will have to be reprinted, so cut carefully.
2. Don't try to cut more than one page at a time. Attempting to cut multiple pictures with the paper cutter will always produce uneven cuts.
3. Use a short-burst pressing action to prevent page curling, dropping maybe 1/2" an inch per press, rather than one continuous cut. By intermittently pressing your hand down on the handle of the paper-cutter, you produce more cutting force with less horizontal pushing force, and are able to stop cutting if the cut goes off-angle.
4. Very slightly brace and move the paper in the direction of the cut to prevent buckling. You can also tilt the page from side to side to keep your cut in alignment.
Try to keep the pages in order, and once you get through this step, we will finally get to build the poster.
Step 5: Taping the Poster Boards
The poster-boards have two sides, gloss (shiny) and matte (dull). I apply the initial structural tape to the gloss side, and the final tape to the matte side (which the pictures will be glued on top of). The structural tape begins with aligning the boards along their edges, and applying three evenly spaced strips of packaging tape over the gap. A single full strip of the packaging tape is then placed over the joining edges. Then the boards are flipped over, and a single perfectly flat piece of packaging tape is placed over the joining edges on the matte side.
To determine how many poster boards you will need, calculate the width of your poster against the width of the boards. Then lay out one row and one column of pages to see if there is enough room. In a picture example, the eighth page goes beyond the width of two boards. Continue expanding this process until you have the proper amount of area to begin applying your pages.
Step 6: Spray, Align, Glue
Spray a light amount of adhesive for a few pages at once (I spray in four-page chunks). When spraying, you don't want there to be a pool of adhesive, as this will soak into the picture -- just enough to lightly cover the area. When applying a page, use only the edges so you can line up the raster dot grid until it is perfect. To an extent, you can slide the edges of some pages under or over others to minimize white excess edge lines. When laying down a full page, smooth it out with your fingers so no air-bubbles form under a page. Continue this process until all of your rows are complete.
Since the adhesive spray carries and goes nearly everywhere, when necessary, go scrub your fingers so they aren't covered in glue and carpet fibers.
Step 7: Trimming the Excesses
Step 8: Grommets (Optional)
A grommet kit should come with a wooden cutting block, a hole cutter, brass male and female grommets, grommet setting block, and a punch.
1. Position your cutting block under the paper on a hard surface, place the hole cutter about 3/4" from the edges and hit it with the hammer a few times.
2. Place a male grommet in the setting block. Then lay the hole in the paper over the grommet.
3. Place a female grommet on top of the paper, insert the punch, and hit it with the hammer. It takes quite a few hard whacks to get a flat grommet.
I suggest installing five grommets, with three along the top edge, and two in the bottom corners. The final picture illustrates the pattern.
Step 9: Hanging the Poster & Results
Place a nail in the center top grommet and drive it into the wall. Since the poster is so lightweight, you don't need to worry about placing it into a stud - drywall works fine. Now you can tilt the poster until it is straight, I suggest asking a friend to help, then drive in nails on the other corners.
There are a few photos of posters I have made in the images section, accented by my custom house lighting.
Now you have a work of art that will greet any guests who enter your home.
Have fun, good luck, and enjoy!
If you have any ideas or suggestions for improving this instructable, I invite you to share them so I may improve the guide to become more helpful. I would also love to see any posters you produce from following this guide, as well as receive constructive criticism or comments.