Limiting current draw on a camera battery charger
Many chargers use a fancy charging method called pulsed or burp charging:



(from http://www.mpoweruk.com/chargers.htm)

A high current is used to charge for a certain pulse length, and after, the battery receives a short discharge pulse. Effectively, this increases the charge speed, however, this method depends on certain calculations for the optimal voltage and current to charge with.

If you change the input current and voltage of the charger, you can't expect this to work properly anymore, which may harm the battery and/or increase the charge time.

Therefore, it would be the best not to use these devices together, but to get a power supply rated for 1.5A. 

However, if you bought these items together, there's (almost) nothing to worry about. Many devices get hot during normal use (especially wall warts). And if it booms, you have your warranty.