It may sound like a silly question, but i assumed that 50i meant 50 frames per second interlaced.
However, when i hookup my Sony Z1 to the PC and start capturing with CapDVHS, it tells me it's actually 25fps.
I'm a bit new to HDV, could someone shine some light?

Don't worry, it's not a silly question.
The "i" in 50i means it's an interlaced format.

It is referred to as 50i because there are 50 interlaced FIELDS per second.
2 interlaced fields make up 1 frame.

So 50i equals 25 frames per second, or fps.

These designations got popular to avoid confusion once progressive shooting became common. That way we don't confuse 25fps interlaced with 25fps progressive (50i vs. 25p).

Thanks.

I gues it will take some time before standards become completely standardized, like Avid-editing systems who use 25i instead of 50i.

G's

It's just the terminology that's confusing. 25i means exactly the same as 50i.

I've wondered about this! Thanks for the question and explanation, you guys.

(For Dylan: "You see, my mule don't like people laughing. He gets the crazy idea you're laughin' at him. Now if you apologize, like I know you're going to, I might convince him that you really didn't mean it.") :)