Battery and Cal information on the 310T
The 310T, as a transmission densitometer, is designed to measure densities up to 5 or 6. Reflection densitometers top out at about 2.00. The statement that the calibration point should be about 1.5 is correct for a reflection densitometer, but for a transmission densitometer the calibration point is about 3.00.
The problem with holding the calibration is due to a dead battery in the unit. The clock stopping is caused by the same problem. THe battery is located inside the unit and is fairly easy to access, but the battery is soldered into the unit. Although a pain when you want to replace it, ithis allowed the battery to last effectively for about 3-5 years! Someone fairly handy with a soldering iron can remove and replace it themselves.
THe battery and a calibration reference are avaialble. The part number for the battery is FE15-09 and costs $31.59. The calibration reference part number is 31968 and costs $41.00. The unit can still be repaired and recertified through X-Rite for $480.00. They would replace the battery, provide you with a new calibration reference and recertify the unit. If other components or systems need to be replaced, it would all be done for this price.
Call X-Rite to set up the service at 888-826-3046. You can buy the calibrationr reference on line at
www.xrite.com. Just go to the online store.
Pragmatically, holding the calibration value is a convenience but not a necessity. Turn it on, let it warm up for about 5 minutes and calibrate it. The units are designed to stay on for hours at a time as that is how labs used them, constantly. As was stated in anohter post, the calibration reference has a number of steps on it. Always use the step marked CAL or Calibration to actually calibrate the unit. Use the other steps to check the linearity of it. If the values are +/- 0.02 or 0.03, you are fine. Keep in mind that density on a denitometer is just like neutral density filters for the camera. Ever 0.30 increase in density means you lost 1/2 the light (or is a full stop change). It is a logaritmic relationship.
If it were mine, I would get a new calibration wedge and that's it. If you are going to be using it a great deal of the time, then the flat rate repair to get it completely checked out and back into full working condition is the way to go.
Good luck and have fun!
I recently received an X-Rite 310T. It arrived without the calibration wedge, but I have a film of approx. D=3 to calibrate it. My question is: Should the 310T retain calibration values when switched off, but left plugged in, or does it have to be recalibrated each time it is turned on (and allowed to warm up for a few minutes)? When switched off it looses the calibration information. It retains the time/date information for a few hours, but the clock stops when turned off, and resumes when it is powered up again. The on-line instructions say that it should be recalibrated once a week. Does this mean it has to be keep on 24/7 (seems it would burn out the lamp pretty fast)?
Thank you.
Clarence