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Andy Beattie
14-08-10, 01:23 PM
When using a polariser on a DSLR should I compensate exposure or not?
Would all photos taken with a polariser on have the same reduction in exposure or am I better off bracketing for each situation? :confused:

TIA
Andy

wave
15-08-10, 09:23 AM
Hi you will see about 2 stops difference but your ttl metering will sort that out. What you should see is the stand out blues in the sky and reflection from water.
There a great explanation of it here
http://www.whatdigitalcamera.com/techniques/camera-skills/mastering-your-camera/446696/polarising-filter-introduction.html

Andy Beattie
15-08-10, 07:01 PM
Thanks for the reply wave, I've been using polarisers for well over a decade and understand how they work, but I've recently upgraded from 35mm to DSLR and was wondering if technology would compensate for the lack of light, and as the article states "you'll have to compensate accordingly" I guess it doesn't... so I'll bracket my shots as the light entering the lens will differ depending on the filter's rotation ;)

wave
16-08-10, 03:30 PM
Hi I used mine yesterday and the ttl metering seemed to work ok the picture seemed just fine. Hope this helps

Andy Beattie
17-08-10, 09:01 PM
Hi wave, I sorted the solution :D

Yea the TTL will adjust the exposure accordingly to a filter being fitted, but with a polariser it under-exposes (mine's by 1.5 stops) so you still have to compensate for the lack of light reaching the sensors or your pictures will be under-exposed (OK it's only 1.5 stops, but it's still under-exposed) ;)