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How to increase brightness in smaller steps?

I have a Lenovo Thinkpad T60 running Oneiric. According to the files in /sys/class/backlight, I should be able to adjust the brightness level to a number between 0 and 7 (and I am able to do this successfully in terminal using

echo 4 > /sys/class/backlight/acpi_video0/brightness

). However, when using the keyboard button (Fn+Home, Fn+End), the brightness levels adjust by increments of three. For example, if the brightness is all the way up at 7 and I press the button once, it lowers to 4, then again to 1, then 0. I would like to change this so that it changes in increments of 1. E.g. It starts at 7, lowers to 6, then 5, and so on. Ideas?

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marked as duplicate by Tom Brossman, devav2, hexafraction, Jorge Castro, Eliah Kagan Oct 9 '12 at 0:32

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

I researched this awhile ago, but there seemed to be no easy solution. The reason, as I vaguely remember, it skips is that FN+* is getting sent twice for a hardware-related reason. Basically, the keyboard event is sent twice and the brightness always increments by 2 levels. – Hemm Sep 28 '12 at 4:52

I'm not sure about those numbers, but on my HP laptop I used xbacklight to change my brightness. The brightness varies between 0 and 100 and pressing the brightness up/down keys changes the brightness by 10. I wanted something like five, so I mapped a key to the command

xbacklight -inc 5


xbacklight -dec 5

You might be able to use this as a workaround to your problem.

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Anyone mapping keys to this should add -time 0 -steps 1. Otherwise, xbacklight applies fading by default - which seems to really wind up your (or at least my) CPU when 'scrolling' brightness by holding down the key. I'm talking all cores rising from 45 to 60 degrees, over just a few seconds - best avoided... To be fair, I'm using 1% increments - where fading is even more pointless than normal - but still, don't tax your CPU if you don't have to. – underscore_d Oct 18 '15 at 23:10

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