Power points aren't mine unless otherwise stated. (◠‿◠✿)

1. Colony Counter

2. Colony counter

3. Colony counter
• A colony counter is an instrument
used to count colonies of bacteria or
other microorganisms growing on an
agar plate.
• An instrument designed to
conveniently count or assist
counting colonies of microorganisms
on a plate containing a gelled growth
medium.

4. Colony counter
• One variety uses a pencil-like rod with a metal
tip, which is connected by an electrical
connection to the gelled growth medium; when
touched to a colony on the plate, the completion
of the electrical circuit causes an increment of 1
unit on the readout of the colony counter.

5. Early counters
Recent counters
• Early counters were merely
lighted surfaces on which the
plate was placed, with the
colonies marked off with a felttipped pen on the outer
surface of the plate while the
operator kept the count
manually.
• More recent counters attempt
to count the colonies
electronically, by identifying
individual areas of dark and
light according to automatic or
user-set thresholds, and
counting the resulting
contrasting spots.

6. (for the automatic colony counter)

7. 1. Place the
Petri-dish
on the colony
counter
2. Count a Petri-dish by clicking the count button
on the software.

8. • 3.The results will be displayed indicating the
number of colonies.

9. The Recent Colony Counter
• The automatic colony counter has the ability to
separate the image of combined colonies for the
user to magnify each colony.
• The recent colony counter is connected to a PC.

10. For the old/digital colony counter

11. The Old Colony Counter
1. Place the colony counter on the lighted surface
with the colonies marked off with a felt-tipped
pen on the outer surface.
2. Keep the count manually

12. Comparison
Recent
Old
• Is indeed faster and easier to
use
• More efficient for observation.
• Hard to use
• Manual counting
• Not so efficient compare to the
recent