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Topic #152: How to Use Photoshop to Create Puzzles
By Teresa K (fasstar)

#1: Teresa K (fasstar) on Feb 20, 2009

Using Photoshop to create puzzles

About Photoshop

Photoshop is a graphics editing program that is sold by Adobe. Sorry, it’s not free. I have Photoshop 7 that I bought many years ago. There are newer versions, but I think these instructions should be basic enough to apply to any version. You can probably achieve similar results using free paint programs, but I use Photoshop, and that is what I will describe here.

Make a background grid:

Open a new puzzle of the size grid you want. A popular size is 40x40. Before filling in any pixels, take a screen shot (hit the key that says “Print Screen”). This will put the image of your entire monitor screen onto your computer’s clipboard. Open Photoshop and create a new file. Photoshop will automatically make it the same size as your clipboard image. Paste the clipboard image into the new blank image. Set view to actual pixels size. Crop the image to just around the outside edge of the grid. Flatten image. Save the image and name it something like grid40x40.jpg. Or, you can cheat and download the grid I already made: http://come-over.to/Play/PBN/grid40x40.jpg

Choose a suitable photo:

This is not all that easy, as there are very few photos that you can turn into a good quality puzzle. After several attempts (and failures) you will eventually figure out how to spot a workable photo or image. Watch for good contrast with an even ratio of dark to white, and not too much shading.

Prepare the image:

When you find a desirable photo or image on the Internet, copy it (so it will be placed on your computer’s clipboard). With Photoshop open, click on “new.” Again, Photoshop will automatically choose the dimensions of the image you copied. Paste the image. Change it from color to grayscale. Play around with the brightness/contrast settings (click on Image, Adjustment) to get as much contrast without losing clarity. You want just black and white, no gray. You can also play with the threshold function. I may use contrast or threshold or both. You can also use the Pixelate Filter (Mosaic). Some methods work better than others, depending on the image. The next step is optional, try it and see how it works for you. If the puzzle is to be 40x40, then crop the image so it is perfectly square, then change the image size to 40x40 pixels.

Put it all together:

Open the image file named grid40x40.jpg. Copy and paste the black and white image on top of the grid. Now you can adjust the black and white image to fit on the grid. Click on Edit, Transform, Scale, then click and drag the corners of the black and white image layer to fit properly over the background grid. Now adjust the opacity of the image layer so you can see through to the grid. The opacity option is on the Layers window. I use about 50% opacity. Make sure the image lines up right with the grid. Flatten the layers then save the image as a jpg file. Print it out and use it as a guide for creating your puzzle. After you make your beautiful puzzle, use the checker to find out that it is not solvable, then spend several hours editing your puzzle. Sometimes you just have to delete and start over. Not necessarily with a different image, but using different sizes and options to get a different rendering. Good luck!
#2: Jan Wolter (jan) on Feb 21, 2009
Some pbn puzzle websites include tools that automate a process like this - converting an image into a puzzle. I suppose I could do that. It's a larger hunk of work.

There is a free alternative to photoshop. It's called "gimp". It's powerful but has a weird interface. There is a version called "gimpshop" that more nearly duplicates photoshop. I've never tried gimpshop myself.
#3: Steve Johnson (swjohnson12) on Feb 21, 2009
Instead of changing the layers opacity, just use the Magic Wand to delete all the white color (you need to make a copy layer 1st - then shut off the original layer. The only thing left to show is the black. Then drop that on a grid.
#4: Teresa K (fasstar) on Feb 21, 2009
Actually, I like to see all the grid lines for easier counting and to save on ink.
#5: Adam Nielson (monkeyboy) on Feb 25, 2009
Sounds like some cheating going on there... LOL J/K.
I will stick to my own. It all sounds very technical anyway. Thanks for the info, Teresa.
#6: Jota (jota) on Mar 6, 2009
I hope to have the time to try it sometime, thanks!

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