TTL-level camera with MAX3232 installed - is that really TTL-level or an RS232-level?
The uCAM came in two different versions (it's now obsolete and superseded by the uCAM-II) - a TTL version and an RS-232 version.

From the datasheet:


  The uCAM is available in 2 models that offer different versions of its serial interface. The uCAM-TTL has low voltage serial TTL levels which can be directly interfaced to a micro-controller and the uCAM-232 has a RS-232 voltage transceiver that can be interfaced to any host system COM port such as a PC.


It looks like you have the RS-232 version.