Image adjustments not functioning

[alanesq]

Hi,

I am using one of the cheap esp32-cam modules from eBay with the ov2640 camera. Arduino IDE v1.8.12 with the ESP32 board manager v1.0.4 (running on Linux Mint).
The image adjustments such as brightness, contrast etc. have little or no effect and eventually seem to lock the device if I adjust several of them.

BTW - I would be very interested if you know why this is happening as I am also having similar problems with a sketch I have recently created and it seems it may be a common issue when using the ov2640?

[SouDGitHub]

Got some crashes and artefacts on my modules and I thought it could be my sketches (using platform IO)
Then tried bitluni sketches to check if camera is working well (I didn't make timelaps project before because I didn't know how to change the web page... plz bitluni tell me how to !!!!!!)

I changed tonight the clock frequency to 10 MHz and it solved all my artefacts and crashes... Give a try !

I can now correctly print good pictures to the common thermal printer with my algorithm ;)