Gast
Hello,
Does anyone have any experience with Dipse laboratory balances, or specifically with the "Dipse-XL 500" model?
Many thanks in advance for your help.
Thomas Hoppe
cfb_de
Hi Thomas,
Go ahead and buy it, and have faith in it. High-precision laboratory balances (e.g. Sartorius) are many times more expensive. The linearity of these budget models is only there if you’re willing to believe it.
On the other hand: do you really want to weigh your photochemistry down to the milligram? If so, you’d be very, very optimistic about your other sources of error in the lab.
If you want to weigh *precisely*, you should ensure that the balance maintains its accuracy within the range of 0.1g to 1000g (+tare!). Otherwise, the only way to work with true precision is to weigh each component for your homemade solution individually into measuring flasks and top them up with freshly distilled water at a defined temperature (usually 20°C). Then remove the required quantity and transfer it to the measuring flasks for the solution... But you probably don’t prepare photochemistry that way, do you? So, this old trusty scale will do. We used to call such devices (top-pan balances) ‘pig scales’ back in the day. And even today, now that I’m a chemist helping to develop cars, lab technicians are constantly surprised at how much a tiny error of 0.1g can add up to.
In photography, however, that doesn’t matter at all. The error in temperature measurement is far more significant. And when developing film, adding the wrong amount does more harm than the summer sunshine. You can just add the sulphite with a tablespoon, whatever takes your fancy. Five grams more or less makes no difference.
Best regards,
Franz
