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Old 10-08-2012, 23:15   #47
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Join Date: Nov 2006
Location: Florida's Left Coast
Posts: 7,734
Wow, I went away for a couple of hours and 25+ posts showed up before me.

I am generally a fact-checker from way back, but it is so grossly uncommon for anything costing $22 to have an actual accuracy of .02gr that no checking was deemed necessary.

However, the specs don't claim an accuracy of .02gr, they claim a resolution of .02gr. tkglazie, your original post claimed that the scale "measures to .02grains". Measures to (?), accuracy, resolution, and precision are all different animals. Take a look at this article, especially the Real-world Example at the bottom of the page that cuts to the chase:

The other parts of this page demonstrate how manufacturers hedge on precision and accuracy, by claiming good scores for resolution. Built in weighing algorithms may help perpetuate the illusion to the scale's end user. Repeatability and reliability are also mentioned regarding actual precision.

I too would like to prove-up actual accuracy and real precision, and therefore repeatability and reliability in such an economical package - but fear it won't measure up (no actual pun intended).

Of course, normal reloader's check-weights don't go down to .02gr, mine starting at .5gr.; so how we check the Gemini is unknown. There is another related page "Testing a Digital Scale" which seems to give correct procedures for accurate testing if you have the time and patience:

If I am found to be wrong, I most definitely would owe you an apology, but I am not yet convinced. My statement was actually made to convince ADK to choose wisely regarding which random posters to believe and I fear I was somewhat insensitive in the way I did that and apologize now for the insensitivity of my 'sell'.

Kitty N.
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