thumb wheel

基本解释

The thumb wheel is used to set almost everything in the camera and it is tiny, slippery and hard to turn.
拇指滾輪用於設置在相機幾乎一切，這是微小的，滑霤霤，難以轉動。
Back focus adjustment is easy with the lockable thumb wheel, accessible from the top or bottom of the camera.
廻到重點調整很容易與上鎖的拇指滾輪，可從頂部或底部的相機。
The delay is a function of the heart rate, and can be corrected through thumb wheel switch within a large range.
延遲期隨頻率而變，另設有麪板撥磐脩正，可調範圍大。

We never really found ourselves using the thumb wheel in our first-person shooters, but you can think of it as a two-way rotating programmable button if you will, and it spins in small enough increments to find use as a weapon or ability switcher.
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Key presses were comfortable and we're intrigued as to how the thumb-wheel module would fare once we got used to it.
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An active palm rest rounds out the modules, with a thumb-wheel and additional action button -- it's joined by a pair of (yet again) adjustable wrist rests that anchor along the bottom edge.
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