EDIT: I tried installing Photoshop CS6 instead, thinking maybe my system was just not good enough to cope with the fancy new Photoshop CC, it made no difference – I still got horrible lag after doing everything below and using the brush for five minutes. Then I found a solution, which I don’t understand but works. As soon as the lag re-appears, click over to another application, it doesn’t matter what, and click immediately back to Photoshop. The lag is gone. I don’t know if this is because I’m using Windows 10 or a shitty Dell laptop, either way, it’s the only solution that works. And even then, it’s more of a bandaid than a cure.
Photoshop CC (‘Creative Cloud’), especially the 2018+ version, suffers from terrible brush lag on Windows. Here are some things to do to try and solve this, though for me the brush lag comes back after a while, so I regularly have to restart the program.
(And remember to restart the program after each change).
- Switch off Smoothing (平滑) in the Brush Palette.
- Make sure you’re using all available Scratch Disks ( Edit (编辑) > Preferences (首选项) > Scratch Disks (暂存盘)), this is what Photoshop uses when it runs out of RAM.
- Edit (编辑) > Preferences (首选项) > Performance (性能) > change the Cache Level (高速缓存级别) to ‘1’ and the Cache File Size ( 高速缓存拼贴大小) to the minimum (128k).
- Edit (编辑) > Preferences (首选项) > Performance (性能) > click on ‘Advanced Settings’ (高级设置) under Use Graphics Processor (使用图形处理器) > change the drawing mode to basic(绘制模式 > 基本).
More drastically, you can try:
- “Reset Preferences on Quit” from Preferences > General, then restart your system.
- Rename the “Adobe Photoshop CC 2018 Settings” folder in your machine ( on Windows : C:\users\<your name>\AppData\Roaming\Adobe\Adobe Photoshop CC 2018\Adobe Photoshop CC 2018 Settings). (After doing this, Pen Pressure stopped working so I had to reinstall the driver to get it back.)