Light level question

[RogerS]

I'm trying to measure the effectiveness of some sun netting and have an app that makes my phone behave like a Weston.

If the camera setting goes from a speed of 1/1000 sec in direct sunlight down to 1/60 with all else being the same, is that a reduction in light of ...what? 1/1000 > 1/500 = 50% reduction 1/500 > 1/250 = another 50% reduction so we're at ...oo'er...my brain now starts to hurt.

 

[9fingers]

One sixteenth? not that I know anything about camera settings/film
Not sure what your source of confusion is
1/60 =16.7mS
1/1000 = 1mS

Bob

 

[RogerS]

That works, ta. Confirms my own thinking (finally)

1/1000 > 1/500 reduces by 50 %
1/500 > 1/250 of that gives 25%
1/250 > 1/125 of that gives 12.5%
and finally
1/125>1/60 of that gives 6.25%

16 * 6.25% gives 100 !!

 

[9fingers]

That works, ta. Confirms my own thinking (finally)

1/1000 > 1/500 reduces by 50 %
1/500 > 1/250 of that gives 25%
1/250 > 1/125 of that gives 12.5%
and finally
1/125>1/60 of that gives 6.25%

16 * 6.25% gives 100 !!

I think working in fraction of seconds does not help. Convert to mS and all becomes clear

Bob