I agree, looks like the start of a shed.
If you are worried about the wattage of the bulb, be more concerned about what temperature it is at the basking area. You should have a quality temperature gauge that you can use to check the basking area temperature, and mid cage/ambient temperature. Failing that, hold your hand in the backing area for several minutes and if the back of your hand is too hot, its likely too hot for your chameleon too.
Veiled/Chamaeleo:
day basking spot up to 96.5F/36C (Non breeding females and Juveniles hottest spot should be kept at a lower temp, closer to 80F)
day mid-cage / ambient range 70-80F/21 -26C
night to a low of 60F/15.5C (Juveniles only down to 68F)
Panther/Fucifer:
day basking spot 90F/32C (Non breeding females and Juvenile basking spot should be kept at a lower temp, closer to 80F/26C)
day mid-cage/ ambient range 70-80F /21 -26C
night to a low of 65F/18C (juveniles only down to 68F)
Jacks / Jax / Chamaeleo jacksonii
basking 82F (75F for juvies)
Ambient temps in the low 70s
night 60F