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View Full Version : Accuracy: Hand-held or Digital Refractometer??


redmarble
05/09/2011, 06:24 PM
Upgrading... Would I be better off with a hand-held refractometer, like DD, Vee Gee, or Premium Aquatics than the Milwaukee/Hanna Digital Seawater Refractometer?

Aren't the hand-held ones more accurate?

The Milwaukee Digital Refractometer says that it's accurate to 0.002 (Milwaukee Link (http://www.milwaukeetesters.com/MA887.html).)

Anybody knows the specs of the DD, since I can't find the accuracy of it? Is it the same as that of the Vee Gee's, 1.0
0.001, Vee Gee Link (http://veegee.thomasnet.com/item/salinity-refractometers/stx-3-salinity-scale-optical-refractometer/43036-2).


Why would I want to buy the Milwaukee Digital Seawater Refractometer besides ease of use? Are hand-helds more prone to human error?


http://www.livingrock.co.uk/acatalog/dd_refractometer.jpg or http://www.novatech-usa.com/core/media/media.nl?id=1179&c=ACCT119126&h=e04a4c3c57a097a78ed9 VS http://premiumaquatics.com/prodimages/millw/MIL-MA887.jpg

muffe
05/09/2011, 06:30 PM
Hydrometer IMHO. For the same reason a sundial is more accurate and reliable than a modern Rolex :)

bertoni
05/09/2011, 06:56 PM
A hand-held refractometer calibrated with a calibrated saltwater solution should be fine. I preferred using a conductivity meter, but both are fine for our purposes. I would avoid the Milwaukee, since it's not very accurate, even if it manages to live up to its specs.

I haven't used the refractometers that you listed. Mine is an inexpensive model from an online vendor, and it seemed fine.