I have been shooting for just under 2 years now and my fundamentals in normal exposure are solid. However since acquiring my first speedlite day before yesterday this has changed the exposure game for me somewhat.

In my experimentation over the last few days I have found that in P mode (which I NEVER use in my regular shooting) everything works pretty much on full auto and exposure on the camera works well hand in hand with the flash. However when I shoot in my usual Av mode I don't find the flash E-TTL jumping in to compensate for under exposure. Basically the camera seems to meter the exposure as it normally would -as if I had never mounted a flash.

* Do any of your have any tips for getting the camera to meter correctly with flash in Av mode?
* Also, is it possible to select the manual flash settings via the camera body as opposed to on the flash directly? I only found FEC settings but nothing for 1/1 1/2 1/4 etc...

Settings I am using;
* E-TTL
* Hi Speed Sync on flash
* Spot metering on camera and using AE lock on a brighter part of the frame ( I tried evaluative but it didn't make a difference)

Gear;
450D + 50mm f/1.4 + 430EX II

I really want to understand this properly since my 'poverty wizard' kit is arriving this weekend and I'm absolutely glued onto the strobist lighting 102 series at the moment!

Thanks for any help
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