Join John Derry for an in-depth discussion in this video Changing bristle spacing, part of Photoshop CS5: Painting with the Mixer Brush.
The Spacing slider is very important.…This adjustment has a great deal of bearing on the performance of your brush.…If spacing is too fine, your brush performance will suffer.…You'll need to look for what I call the 'sweet spot' to match your system's…performance with an acceptable brush performance.…Now, I like to think of the Spacing slider as a performance throttle, and to…show you this, I'm going to use my Right Bracket key here to enlarge this brush,…because I want to get a brush that actually has a bit of lag in it.…
And we may need to really go out of our way to make that happen on this fast system.…Let's just try it here. Okay.…You can see there's a little bit of lag in this brush, and this is artificially…large, but it will get the point across.…If I adjust the Spacing upwards, now let's undo and try it again, you can see…that brush is now a real-time brush.…However, we're starting to get some artifacts from the fact that ultimately…these are a series of individual brush stamps that are spaced close together, to…
- Understanding the axes of motion with a Wacom tablet
- Choosing a brush shape and Bristle Tip
- Adjusting brush angle
- Loading color and control the behavior of the Mixer Brush
- Modifying surface texture
- Simulating the texture of canvas
- Saving tool presets for brushes
- Creating a painting from a photograph
- Painting from scratch with the Mixer Brush
Skill Level Intermediate
Q: What factors affect how well the mixer brushes in Photoshop perform? Does document size (i.e. 72dpi vs. 240dpi) affect the performance of the brushes? How can I maximize brush performance?
A: The recordings for this tutorial were generally done at a standard screen resolution, but a real-world situation will often require higher resolutions. For example, offset printing generally dictates files at 300ppi (pixels per inch). Inkjet printing is often discussed in terms of 240ppi. For web-based viewing, imagery at 72ppi is considered acceptable. You can easily determine the pixel resolution of an image by multiplying the size in inches by the above ppi (pixels per inch) factors.
Let's use a typical real-world size as an example: 20" X 24". This is a common photographic print and frame size.
72ppi = 1440p X 1728p = 2,488,320 pixels
150ppi = 3000p X 3600p = 10,800,000 pixels
300ppi = 6000p X 7200p = 43,200,000 pixels
Note that each of these resolution factors quadruples the total pixel count.
It is the amount of pixels being manipulated that dictates both application and brush performance. With this in mind, we can state that performance decreases as image pixel size increases. There are three primary factors that affect an application's ability to handle large pixel-based manipulation.
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