How often should the D25LT be standardized? Follow

FAQ: "We have two D25LTs and currently we perform the following tests as described in the user manual."

· Standardization every 4 hours

· Color Check and Short Term Stability every month

· Lamp Check quarterly

· Long Term drift and signal level annually

Since we have a very small spec for color (L: 59-74 and a:0-6) can we re-standardize the units once weekly instead of every four hours? We do not expect significant color changes, so it seems excessive to standardize every 4 hours."

Standardization on the D25LT takes 15 seconds so it is not an onerous procedure but you are probably overdoing it given your product tolerances.

Standardization is a reminder process for the instrument, forcing it to match bottom-of-scale (black glass) and top-of-scale (white tile) standards and correcting for any minor drift in the instrument over time.

You can set the reminder (System Maintenance/Preferences) to whatever interval seems appropriate for your application, but a week is too long.

Given your generous tolerances, you could make it 24 hours and that would be fine.

If a user has a tight set of product tolerances, such as a couple of units, once every 8 hour shift would be good.

For the tightest product tolerances of tenths of a unit, use a 4 hour standardization interval.

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