SpudFiles

I want to make a clear chamber for experimenting on things under pressure (food items, plants etc), however, I'm unwilling to shell out large amounts of money for clear PVC.
Ideally it would be akin to a drinks bottle, except it needs a much wider mouth. I was thinking mayonnaise jar, but I don't know if they're airtight, and I would constantly work about little knock causing razor shrapnel to go flying :S

The mayonnaise jar wont do it.
You could also just use a piece of pipe with an endcap and bolt/epoxy a thick plexiglass plate on the other end. You can only view it from one direction though.
Or manage to connect an endcap adapter to the bottom half of a coke bottle.

I know you don't want to spend the extra money, but it is going to help you out in the long run.

Disclaimer...I've never checked for clear pvc, so I cannot say if this would be less costly.

How about a steel chamber with a cheap web cam and light mounted inside? Add a plexi "blast shield" to protect the camera (put the light on the other side of the plexi or all you'll get is a reflection of the light.)

My .02

clear PVC would probably be the best and easiest option...

This isn't a really serious project, hence my not wanting to spend much.
"in the long run" doesn't really come into it, as I'm sure I'll bore of it quickly, it's just supposed to be a fun little experiment to satisfy my curiosity and £35/m (shortest length available) is quite a lot!.
I suppose I could superglue a threaded adapter on a bottle, I'd worry about how well the to plastics would stick though.

The steel chamber sounds viable, but it's probably not far behind the clear PVC in terms of effort/price. I was thinking of a more ghetto-y solution with more readily available parts.

regular PVC/webcam?