Beam size thin?

I noticed a lot of video and pictures of 445's with a really fat beam... take a look at this beam... it is a 445nm M140 with 405-G-2 Glass Lens.

I know the video isn't great... but you can see some of the beam... it seems really skinny compared to some i've seen here? Are there special optics or maybe just different camera exposures? the clover shape in the background is my driver heatsink... 3 pennies ground smooth and thermally adhered to the driver.. the pennies get REALLY hot so I guess it's working!

The beam looks like this - so if you film it from the top you see a fat beam. If you film it from the side, then you see a thin beam. It also depends on the focus. If it's focused to infinity it will look fatter than if it's focused to a point a foot away.

I don't know how you can tell a difference from a video like that. Anyway if the guy is burning stuff, he's probably not using a collimated beam, but rather just focusing down onto a spot so there isn't really a good comparison here.

"focused to infinity" does that mean that the focus ring is tightened all the way to the right?

viking said:

"focused to infinity" does that mean that the focus ring is tightened all the way to the right?

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It means it's focused such that the beam is best for pointing at objects far away.

You can't depend on the focus knob to tell you anything about how the beam is focused. The focal point of the optics could be in front of the lens, at "infinity", or even behind the lens so that the beam is always diverging.