Image contraste in raw and film mode

Sorry for my english. I don't speak very well.
I just bought A black magic cinema camera and i have a problem : the image in raw is ok on the LCD monitor (flat) but when i transfert the file on my computer it's automatically contrast as in video mode... I can't have a flat raw image !!
It's ok in prores hq in film mode.
Can you help me. Maybe my mac config is not good i have a imac last 2011 12go ram, amd radeon 6970hd 1go...
I will have an other one with nvidia graphic cards 2go and 32 go ram maybe it will be ok what do you think?
I have already update the firmware on the black magi web site but it doesn't work. I don't understand...

Thanck you !!

I recommend you post this (or an admin moves it) over to the Cinematography section of this forum. That's the place where the experts in this are.

By the way - how are you looking at those Raw images? You have to color-grade them with the free version of Resolve that comes with the camera.

RAW is NOT flat. This thread will help explain what is going on:
viewtopic.php?t=11446