Power Supply; Loading Of The Battery; Programming Comparator 100; Entry Of The Determined Exposure Value - JOBO Comparator 100 Mode D'emploi

9. Service
10. Scope of delivery
2.

Power Supply

The JOBO Comparator 100 is powered by a 9V
battery (Not supplied with unit). After loading
the battery and switching on the unit, the Com-
parator is ready for operation.

2.1 Loading of the battery

The following batteries can be used for the
Comparator: e.g. Duracell NN 1604/6 LR61/9V
or equivalent types of other manufacturers. A
sliding cover on the back of the unit gives
access to the battery compartment.
3.

Programming Comparator 100

Note: During programming and during all mea-
suring processes the safelight and all other dar-
kroom illumination must be off. The photocell
will respond to any light. To program the Com-
parator you must first make what you consider
an ideal print without using the Comparator.
The exposure values (enlarger height, F-stop of
lens, paper grade and exposure time) must
then be used to program the Comparator for
future use. The JOBO Varioformat Easel and
Test Printer are valuable aids in determining the
exposure values.

3.1 Entry of the determined exposure value

for selective (spot) measurings for B/W
The enlarger height and lens aperture should
be the same as for your ideal print, and the
negative for that print should be in the negative
carrier of the enlarger. Turn on the enlarger.
11
Turn off all darkroom light. With the main switch
, turn on the Comparator. At this point one of
the two red LED triangles will be lit. The time
scale dial is set to the exposure time you
used for your ideal print. Place the Comparator
on the easel or baseboard so that the lightest
part of the projected negative that still shows
some details is covered by the measuring cell
. Choose this spot as close to the center area
of the negative as possible. With the Compara-
tor in place, turn the adjustment knob
the balancing lights change from a red tri-
angle to the green center LED. Individual set-
tings can be noted on the white border in pen-
cil. After that do not change the position of the
adjustment knob anymore.
Your Comparator is now set for the paper you
have been using. It is <programmed>. Now you
can determine exposure time required for an
unknown negative used with this paper.
3.2 Entry of the determined exposure value
for full area (Integrated) measuring with
B/W and color
The diffuser supplied with the Comparator
should be placed under the enlarging lens in
the light path of the projected negative/slide.
The entry of the exposure value should then be
entered into the Comparator as described in
3.1 above.
until
12