Any difference between tv and aperture?
 

When I use TV, if I magnify to the cameras capacity the f stop changes from 1.8 to 2.8.

Other than not being able to control the f stop doing this is there any fundamental difference between the TV and Ae mode?

and also
If exp + is adding gain, what is exp - doing? Closing the iris? Thus changing the shutter speed value right?
Sometimes it seems the camera is bringing the shutter speed down as opposed to adding sensor gain aswell, is this correct?

Another thing
Does cinemode stay consistant. I set the exposure but when zooming in and out the shutter speed and f stop are constantly changing.

Using "Tv mode", which is better described as shutter priority, you set the desired shutter speed, the camera selects an appropriate aperture for correct exposure. It will also increase gain in poor light.

Using Av mode, which is better described as aperture priority, you select the desired aperture, and the camera then selects an appropriate shutter speed for correct exposure.

The camera also rotates a variable neutral density filter in the light path to avoid extremes of aperture in Tv, or shutter speed in Av.

If you have an SD card in the camera, half pressing the PHOTO button with exposure lock selected via the joystick will show you what the selected aperture and shutter speed are.

This is normal for most cameras when you zoom in or out.... it just means that the lens
is not a constant aperture lens with zoom.

aRghh this camera is a nightmare.
Whats the deal with me setting f2.8 it adding 9db without me even touching gain and then me filming in the exact same conditions a day later and it filming with 0db?

Another thing. If I have exp set on, the gain levels won't change, the image will stay consistantly at the same settings right?

The camera defaults to auto, and takes its best guess at what's needed to get the best exposure. If you fix shutter and aperture, it will move gain around to try to get it right.

Check the manual - there is a way to fix everything - gain, shutter, aperture. Can't remember what it is.

It's a consumer camera; slightly illogically, you generally have to pay more money to get a camera that makes you do it all yourself.

Yes! Its the same as a standard slr lens being 55-200mm zoom with a minimum f-stop of 3.5-4.8 As you zoom through the lens, it cannot be open as much. Only the $1000+ lenses have zoom above 200mm and maintain an f-stop of 2.8 all the way through.