Thermal imaging and fixed vs. adjustable focus

Can anyone here offer advice on which is best, and perhaps why, that fixed focus might be better than adjustable focus, for a thermal camera that will primarily be used to characterize & document PCBAs during DVT? Thanks…


I expect most of the typical arguments for fixed vs. adjustable anything would apply, which generally boil down to flexibility/adaptability vs. ruggedness and cost.

In terms of imaging focus deals with distance to the subject, which in turn relates to field of view. Fixing the focus fixes the distance to the object, and thus the field of view; there’s no moving the object closer to see finer details or further away to get it all in the picture. Not a bad thing for things like assembly line inspection or comparative operations where one would like to limit possibilities of things going out of adjustment, but not very adaptable.

Now if one’s speaking of fixed focal length rather than fixed focus, that’d be a somewhat different issue, translating more or less into the concept of “zoom”.

What’s “best” will vary with any individual application’s priorities and variables. You pay your money, and take your choice…

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Thanks Rick. That was helpful. You confirmed what I was feeling & thinking.