[IronPen]

Hi. I just can't figure out why, but on my MacBook Pro at home, scrolling in Mail.app, Safari, and Chrome all jump immediately with no 'visible' scrolling. Hit the spacebar and, BAM!, you're seeing the next page. However, on my MacBook Air and MacBook Pro at work, both visibly show the page scrolling by. I prefer the former. I've looked at all of the 'scroll' settings in the OS in Preferences and they seem to match what I have on my MBP at home. Any ideas?

[P]

No, but if you use Page Down instead it will always jump one screen down.

[IronPen]

The same 'visible' scrolling occurs on my work machines. I may need to create a video to show what is happening. Basically, on my home machine, page up/down & spacebar jump immediately; I don't see the content of the page scrolling quickly by. I page up or down and immediately I'm seeing the next page. Whereas on my work systems, I see the page content quickly scrolling by. In Firefox, all of my machines exhibit the behavior I want, so maybe you can use FF and see what I mean, assuming you haven't customized it from the default behavior. It pages up and down one page at a time without showing you the content during the operation.

EDIT: This video describes what is happening on my machine at home, but using Firefox as the example since I am at work.
https://dl.dropboxusercontent.com/u/.../scrolling.mov

[Spheric Harlot]

Smooth scrolling turned on in the General or Appearance System Preferences?

[P]

I mean if you push the Page Down button, it will always jump and never scroll.

[IronPen]

Originally Posted by P 

I mean if you push the Page Down button, it will always jump and never scroll.

Not on my work Macs. The behavior with the Page Up/Down buttons behaves the same as the spacebar, as shown in the video. I wish I knew how to get my work Macs to scroll like the machine at home.

[IronPen]

I finally found out how to change the spacebar scrolling behavior in MacOS (OS X) thanks to a web search.

To get the spacebar to cause the page to jump rather than visibly scroll, try disabling the animations for scrolling by running:

defaults write -g NSScrollAnimationEnabled -bool false

To view the setting, run:

defaults read -g NSScrollAnimationEnabled

Once set, the output should be 0 (zero).

After setting, relaunch applications.

[Curiosity]

Why not just drag the thumb (the sliding part) up and down?

[IronPen]

Originally Posted by Curiosity 

Why not just drag the thumb (the sliding part) up and down?

Mainly because that is slower and more cumbersome in many cases than hitting the spacebar. There are numerous ways to scroll, but I prefer to keep my hands on the keyboard, so hitting the spacebar is often preferable to reaching for a mouse or using the trackpad.