John, I want to do the same thing! I did a Google search and came up with some good scales. I want one that is battery operated as well. http://www.derbychamp.com/ProductDetails.asp?ProductCode=B105&C...
This a link to a relatively cheap scale. Good luck and let me know what you find!
When Bruce and I weighed the fish at Richmond Mill we used the smallest Boga Grip that weighed in quarter pound increments...certainly getting us in the ballpark but not the total picture of accuracy either. Some of our fish could have been a few ounces heavier, or lighter, than what the Boga said.
At Piney Run Park, where I have been the weighmaster for several dozen tournaments over the past ten years, I have always used a certified digital scale that weighs in 1/100 th of a pound and cost about 400 dollars...way too much for the average giller, but neccesary for tight tourney competition where prize money, and possible state-record catches, may occur.
The largest bluegill ever weighed on that scale from Piney Run was a 12 1/2 incher that weighed 2.48 pounds and was weighed by my former supervisor and angling partner Loren Lustig. These highly sophisticated and expensive scales still have to be placed on a level surface and 'zeroed out' between the weighing of each fish in order to be accurate...some thing we can't always do in the field and battery power can also be an issue. if the charge is weak.
I agree...it sure would be nice to have an accurate scale that didn't cost an arm and a leg.
I take 'em home and use my wife's electronic kitchen scale :-) It sets tare off weight and is accurate enough for baking and such, which is good enough for me. Battery powered, it could be used in the field of desired.