MetroLux One Instructions, middle

Calibration

NOTE: Before you calibrate, a probe must be installed in your light source. See installation instructions.
To operate MetroLux with your enlarger, you must introduce the two in a ceremony we call Calibration. Every enlarger has a 'standard' light output. What we need to do is determine the standard light output from your enlarger and inform the MetroLux. Please follow the next steps closely.
EXAMPLE: Hold down the 'Units' key for one second until the Cal LED is lit. The #1 LED (calibration #1) on the right side should also be lit. If not, roll the memory by pushing the 'Memory' key. With each push the display goes from #1...#2...#3... #4...and back to #1 again.

Turn on printing lamp by pressing 'Focus'. (Coldlight people, allow lamp to warm up...five or ten minutes).
Push 'Start'. You are now calibrated. Be sure that LED #1 is lit. Leave the Cal mode by pushing 'Units'. You may never have to calibrate again. More details about calibration are given in Advanced MetroLux below.
One last note about the calibration number. The optimum number is between 10 and 127. If the calibration number falls outside this range, accuracy suffers and MetroLux may make mistakes.
Write your calibration number down. True, MetroLux does have non-volatile memories, but it's still wise to protect yourself from darkroom gremlins.
Should you get a number less than 10, there are three possibilities: the probe is not plugged into the back of MetroLux, your lamp is not warmed up, or the probe is not seeing enough light. In the latter case, you'll have to move the probe. For numbers greater than 127, the probe is seeing too much light and is too close to the source (and is probably too hot).

Advanced MetroLux

Exposure Memories #1, #2, & #3

MetroLux has three of its memories dedicated to exposures. This gives you three different exposures to work with without constantly changing the memory. There are many ways to use these three. Our favorite is to keep the base exposure in Memory #1, the test strip exposure in #2, and our proofing exposure in #3. If all these memories are troublesome, #2 & #3 can be masked. See Custom Code Numbers.

Relative Exposure Control: The Percent Function

When would you use the percent function?

To apply dry-down factors.
The dry-down effect is best explained in The Print by Ansel Adams, page 82.
To wit: most photographic printing papers become slightly darker as they dry, most noticeably in the highlights of the print. To determine the value of this dry-down effect, expose a normal print . If it looks good wet, print another 5% lighter. As it dries it will match your wet print. (Nominal dry-down factors range from 1 to 11%.)
To have MetroLux apply this predetermined dry-down, press 'Memory' key until the % LED is lit. Using the 'Down' key, set the display to 95%.

Press the 'Memory' key again until the #1 LED is lit with your printing 'time' displayed. The #4 LED will also remain lit reminding you that your exposures will now run 5% shorter and the metronome will beep 5% faster. Whenever the % factor is other than 100%, the % function LED remains lit as a reminder.

The % function affects ALL exposures, in Lux or Seconds mode, Focus or Start (exposure). Before work on another negative begins, it is important that the % function be reset to 100%.

To incorporate 'fudge factors'.

You'll notice that the % function has a very large range---50 to 200% (plus or minus one f/stop.) This is much more than necessary for dry-down compensation. Why the overkill?

Consider the negative printed regularly. It would be nice to always use the same exposure for making that print -- regardless of the paper's type, grade, serial number, or age. You would simply pull the negative from your file, transfer the notes from your prior printing into MetroLux, and make the print.
But say you desire an enlargement 20% greater than the notes on your negative sleeve dictate. Use your original exposure with a 120% factor.
Or say you are unhappy with a print made on #3 Oriental. Too flat? Whip out the box of #4, plug the predetermined emulsion speed difference factor into the % function, and print the compensated print.

More Calibration

If you have a second lamp, with a photo sensor installed, it is possible to store its Calibration number in Memory 2.
EXAMPLE: You use a coldlight but sometimes print with a tungsten light. You've already calibrated your coldlight in Memory 1. Now calibrate your tungsten in Memory 2.
To use Memory 2, press the 'Memory' key until LED #2 is lit. Calibrate as with lamp #1.

Remember, when entering Cal mode, whichever calibration number is displayed, 1 or 2, that is the one you were using. Whichever memory is displayed when you leave the Cal mode is the Calibration number you will be using. You cannot leave the Cal mode without being in Memory 1 or 2.
For those of you using two light sources with one MetroLux, there are ways of configuring the wiring so that plugging and unplugging of light sources and probes can be eliminated. You will need a Y-adapter for the probes. See the list of options at the end of the instructions.

MANUAL CALIBRATION

A second way to enter the calibration number is to input directly using the 'Up/Down' keys. With the lamp off, run the display to the calibration number you want. Again, you are limited to numbers between 10 and 127. This feature can be handy if you want the beeps to come at longer or shorter intervals...other than the approximate one second interval achieved through calibration. Say you'd like the beeps to come at two second intervals. To do this, double the calibration number.

Lamp Intensity Monitoring

If you were wondering what happens when MetroLux is in Cal mode-Memory 3, wonder no more. This function displays the lamp intensity as monitored by the probe. It is a real-time readout of the light source intensity. It is the number that MetroLux would store in Memory l or 2 if you were to proceed with the calibration procedure. This number is directly proportional to the intensity of the lamp. If you're using a cold light, you may notice this number change dramatically as your lamp warms up.

Custom Code Number

When MetroLux is in Cal mode-Memory 4, some adjustments can be made to your Lamp Controller. You can: (1) turn the beep off, (2) hide Memories, and (3) control LED brightness.
{Notes inside these brackets refer to the Custom Code Number chart below.}

Beep {B}
Turns the beep off. {B is beep on, dash is beep off.}

Memory {M}
With this adjustment, a push of the 'Memory' key will toggle between Memory 1 and Percent, bypassing Memories 2 and 3. This is convenient when using only one printing exposure. {M is all memories, dash is Memory 1 and Percent.}

LED Brightness {1,2,3,4}
There are four levels of brightness for the LED display. {3 is standard and factory set. 4 is one level brighter. 2 is dimmer. 1 is very dim.}

Your Custom Code Number

Decide on the set-up that you'd like, look up the corresponding bold number in Table 1, and enter the number as explained below.

EXAMPLE: Let's say you'd like the Beep on but want the Memory to toggle between #1 and %, and the LEDs dimmed a little.
Keep the Beep...that's a B. Toggle the Memory...that's a dash. Dim the LEDs...that's a 2 on the end. Get the order correct. Look up 'B - 2 ' below.
Here it is again in table form.
function choices example
Beep B - B
Memory M - -
LED Brightness 1 2 3 4 2

Custom Code Number Selection.
If we take 'B - 2' below, we can look up the custom code number. Going down the list we find that it is equivalent to 13. This is the number we wish to install in Memory 4 of the Cal mode.
In the Cal mode, go to Memory 4. Enter '13' into the display using the 'Up/Down' keys. (See Figure 7.) Simple. The lamp need not be on.

Cal Mode, Custom Code Number

00 - M1
01 - M2
02 - M3
03 - M4
04 - - 1
05 - - 2
06 - - 3
07 - - 4
08 BM1
09 BM2
10 BM3
11 BM4
12 B - 1
13 B - 2
14 B - 3
15 B - 4

Table 2. Custom Code Numbers

Jot down your favorite custom code numbers for future use. This can save a lot of time later. (The 'factory set' custom code number is 11.)

Memory Reset
The table below shows the location and use of all seven (7) memories in MetroLux, their names, and their factory preset value (bold numbers). You may reset these numbers at any time. To do so, turn on MetroLux while depressing the 'Units' key. Pressing the 'Start' key places the numbers into non-volatile memory. If you want your old numbers back, turn off MetroLux before pressing the 'Start' key. When you turn MetroLux on again, the original numbers will still be there.

Cal Mode Printing Mode

# 1 Calibration 1 (16) Lux/Sec 1 (1.6)
# 2 Calibration 2 (16) Lux/Sec 2 (1.6)
# 3 Light Intensity Lux/Sec 3 (1.6)
# 4 Custom Code # (11) Percent (%) (100)


Very Early MetroLuxes (serial numbers a little larger than 923)

These MetroLuxes don't have a power on reset. Here is how to tell if you have one these 'very earlies'. Go to the Custom Code area and see if the range is 0 to 15 or 0 to 127. The latter is a 'very early'. Fear not. These work fine, but have spots for features that were never incorporated. The Custom Code numbers are the biggest problem and I don't have the table anymore (It is in an old Mac computer. If you have a table and could make a copy for me, that would be slick.)

Here is how the old table worked. There are four controls: count by tens/halves, one or three time memories, beeper on or off, and 4 brightness levels.

Brightness levels change every count. 3 is brighter than 2 is brighter than 1 is brighter than 0. This repeats all the way up to 127. Brightness is bit 0 and 1 (if you know the binary here).

Bits 2 and 3 don't control anything and thus everything repeats with these bits.

Bit 4 is the Beeper on/off. So the beeper is off from 0 to 15 and then on from 16 to 31, etc.

Bit 5 is the Memory, either one or three. Memory is all on from 0 to 31 and only one from 32 to 63, etc.

Bit 6 is the count by 0.5 or 0.1 settings. Counting by 1/10 with the custom code number from 0 to 63 and counting by 1/2 from 63 to 127.

The old factory settings on these units was 20, but I like 23 for brighter LEDs.

If the unit acts weird, make sure the percent is between 50 and 200.

Thanks to Paul Rice for this lesson with older Metrolux units.