Battery Chargers Perplexes Me.

Ever notice all the different ways manufactures make battery chargers behave?  These two simple NiMh Chargers, dim the one light when the battery is done.  But it doesn't do it that way for all my new batteries just some of them.  Which is why it perplexes me.  It was also interesting to figure out the best way to take a picture of these.

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