Rebel Stenlight review

[Mark620]

I thought that the light had to increase 4x (not 10x) to perceive the 2x increase?

You are right about this, I was only thinking about the math...how an exponential curve works.

I should have added "without turning on the lights" to my original posts. So, to re-phrase the question...how can you tell the difference between the two lights if they are sitting side-by-side without turning them on? Is there a visual difference?

It is not possible due to the optic(culminator) being in the way.

[rlboyce]

Resurrecting an old thread here...

Does anyone have any sources for this claimed exponential effect in vision regarding light intensity?

[LukeM]

This is what I was able to dig up by looking through old CPF threads.

http://en.wikipedia.org/wiki/Stevens%27_power_law

http://en.wikipedia.org/wiki/Weber%E2%80%93Fechner_law

[rlboyce]

Thanks!! That's exactly what I was looking for. Reading the Wiki articles, it would appear that this is more of a concept with some supporting evidence as opposed to being thoroughly tested and verified. Also, it seems that many individuals' perceptions will deviate significantly from what the theory would predict. Nevertheless, this possible logarithmic effect is something to keep in mind in the future and gives me something to pay more attention to.

[Jeff Bartlett]

Speaking of heinously old threads where I had no idea what I was talking about, it's worth noting that the "premium" iteration of the Stenlight has continued to improve steadily in terms of light output and efficiency since this article was published. My wife's Stenlight, purchased in mid-2010, is noticeably brighter than my 2008 version; eventually, it will probably make sense for me to seek a second upgrade, since the unit itself has served me very well over the years.