How to install your SEL LED.

First remove the old bulb/battery tube, this is not needed anymore.  Some SEIs have a stud in the battery compartment see below for details.


Balance the SEL LED on top of the NEGATIVE end of the cell, the non pip end.  Don't panic if you get it backwards it just won't work, no damage will be done.


Simply insert all the way in and replace the cap.

To use, turn the rheostat on the bottom of the cap fully clockwise then it is just as normal except there is no calibration process.  Indeed the meter may not move at all and is now redundant.

The SEI LED leaves me adjusted to my SEI, yours may be different, to adjust the output of the SEL LED there is a trimmer on the PCB.

Do a few tests, get a value for any offset, this may only be 1/3 stop or so.

The way I adjust mine is to find a surface that is evenly lit, artifical light is best, it is stable.  Measure it using the SEI, note this figure, adjust the trimmer a bit, re measure the surface and keep on adjusting untill the new reading is the correct amount different from the first reading.

The trimmer, clockwise for dimmer, this has the effect of increasing the reading on the SEI.

There are some SEI Photometers with a stud in the battery/bulb compartment, this stud needs to be removed.

If your tube has this hole in it there may be a stud in the battery compartment

Here it is, simply remove the three screws and withdraw the ring and stud with a pair of tweezers, it is best to keep the SEI meter down during this to save the photocell dropping out.

Just undo this screw and re insert the ring, getting the screws back can be fun, I use some BluTak to hold them onto the end of the driver.