Using imported images in Ultrafractal

When I set this blog up I was asked about how I created the images for it. I promised that I would explain it. This is me trying to follow up with that commitment. This isn't meant to be a step by step tutorial. It's more of a high level view of what I do. I am assuming that you know how to use an image editor like Photoshop and you can use Ultrafractal.

There are 2 image importing tools, that I know of, that that will create an Ultrafractal coloring formula out of images. They are Bring it in and Sprite. I'll focus on Bring it in.

Prepare the image

The first thing that you have to do is to come up with an image and get it ready to be imported. I snapped this picture while shooting butterflies (with my camera) at an exhibit at the Pacific Science Center.



I like to use imported images the same way that I use trap shapes. To create a "trap shape" I needed to pull the flower out of its original background and place it into a transparent background. I did that by selecting the area that I wanted to keep and then doing a copy-paste of that area into a new image that had a transparent background.

The trick is to do the selection from the original image. In this case it was easy to use the Photoshop magic wand tool to pick the red. It grabbed everything but the dark center. I used the lasso tool to add the dark center to the selection. Most of the time it is not that easy. Usually extra chunks of the image are copied and pasted in to the new image and need to be erased.

Prior to the copy and paste I usually like to feather the selection by a few pixels to smooth out the edges.

Then copy the selection and paste it into a new image that has a transparent background...

Save the image in a format that will preserve the transparent background, like as a PNG.

The size of the imported image is an important consideration. If you are going to render a large fractal for printing, the imported image can start to pixelate. I like to import the largest image that I can, keeping in mind that each pixel is mapped into an array in the UF coloring formula. This sucks up a tremendous amount of computer memory while using the formula in UF and slows down the system response time.

Bring it in has the advantage of allowing you to import larger images. I haven't used Sprite in a long time but it didn't seem to handle large images very well.

Create the Ultrafractal UCL

You have your PNG image and it's time to fire up Bring it in...


Make sure that the new UCL is created in your My Formulas folder. Give the new UCL a name like "hib.ucl". This is like creating a folder like "dmj". The Name is the name of the formula inside of the UCL. Be sure to select one of the two V3 templates. In fact, before closing Bring it in, create a second formula and place it in the same UCL by changing the template to the other V3 template and changing the Name.

Use the UCL in Ultrafractal

Now it's time to fire up UF and start using your new UCL


You went through a lot of effort to create an image with a transparent background so that you could take advantage of that transparency in your fractal image. The two V3 formulas have different approaches to create the transparency. Formulas created from the Standard-NonDirect-V3 template need the base color to be transparent (shown above) as well as an area of the gradient. Formulas created from the Standard-V3 template only needs the base color to be transparent.

Be sure to set the "Color by..." parameter to "Last Z" or "First Z"

You might need to adjust the "Trap Alpha Threshold" parameter

I like the formulas created by Standard-NonDirect-V3 template. It somehow allows you to use the gradient to change the color of the imported image. The gradient is linked to the image trap through the "Choose Index By?" parameter.

Mark put some very handy image filters into the formulas. They're worth playing with.

It goes without saying that you should adjust the size and rotation of the image trap so that it looks good.

Also take advantage of the "Start Iteration" and "Skip some Iterations" to turn off some of the traps.

Feel free to comment or ask questions here or in the forum