John Ferguson
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Registered: Jul 19, 2003
Total Posts: 1493
Country: United States
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 Re: Yet another alternative to ExpoDisc | |
Did a quick unscientific comparison using generic white coffee filters compared to my expodisc. Pointed at spotlight in kitchen and took one aRBG RAW shot. Brought RAW files into C1 to see what it said the white balance was in P mode aRBG.
Using Expodisc: 3900K -2 tone balance F2.8 1/45 sec
Two coffee filters: 4300 -1 tone balance F3.5 1/90
Three coffee filters: 4075 -2 tone balance F2.8 1/60 sec
Before taking the RAW files I tried two .jpgs, one using two coffee filters and one using the expodisc. PS CS showed that two coffee filters let 12% less blue light through than the expodisc. This compares fairly close to the RAW findings of two coffee filters which show about a 10% difference. Using three coffee filters narrows the difference to about 5%. This is far better than pringles lids or coffee can lids that I have tried in the past.
While I am sure that there are differences in brands of coffee filters and 50 trials averaged would give you a more accurate result, I think that if you used three coffee filters to set your custom white balance, you would be within 5% of what an expodisc will give you. Is that small difference worth the price of an expodisc? Only you can answer that. But one thing for certain, three coffee filters is a WHOLE lot better than AWB, a pringles lid, or a coffee can lid.
Anybody want to buy a like new 72mm expodisc? :eyes:
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