Chapter 4; phototransistors reversed?

Hi,

In chapter 4 for the color mixing lamp project, as per the instructions we need to connect the long leg of the phototransistor to power and the short leg to ground (along with the resistor).

However in my case only the reverse setup seems to work i.e I get readings from the phototransistors only when I connect the short legs to power and the long leg to ground.

Has anyone experienced similar behavior or I might be doing something incorrectly?

thanks for the help!