wide angle converters
 

Is it possible to use these with the 7d? I know, better to get the Tokina, but for video use, where sharpness is not paramount, a screw on adapter would be efficient and cheaper. Any stories?

they are VERY soft

You can get teleconverters that go between the lens and the body for increasing effective focal length, but as far as I know, there's no such thing as a decent wide-angle adapter in the EF still photo lens world... image softness and vignetting being the culprits. Best solution is to get a dedicated wide-angle lens.

So I realized I have an inexpensive WAD made by Vitacom. it's the DSLR HD-Pro Digital .5x wide angle lens. I use it on a JVC HD100.

Here it is on and off a Tamron 28-75mm 2.8 lens in ambient light. No flash.

It really is ironic, the wide angle adapter is made for fixed lens cameras so they can get increased range to mimic the more expensive SLR. The whole idea of a SLR is to interchange lenses.

Independent lens manufacturers exist to give cheaper alternative lenses for SLR cameras.

I'm not feeling the irony. What if you don't want to spend $600 for a WA lens? An adapter makes a lot of sense and saves a lot of cents for that person.

A cheap secondhand wide-angle SLR/DSLR lens would be far wiser to buy than any adapter in my opininon...and the image quality in most cases would be far better.

the problem is there doesnt seem to be any cheap wide angle old manual lenses (from what i could find at least) once you take into account the crop factor.. When I looked into it all i could find was a Nikon 13mm that goes for about 15,000$ second hand!

I'm interested in how you get on Brian as I was also curious about the adapter solution

It all depends on how wide you want go. A full frame 15mm or 17mm or 18mm is still quite wide in 1.6 crop.

thats true.. in my case i have the 17-55 though so i was looking for something a bit more extreme

The 15mm full frame Sigma is a decent lens. It is true that you have less options in full frame old MF lenses when you go wider than 15mm, and extreme wide beyond that tend to have curved or bowed images. That is just one of the reasons why I prefer 5D and D3s over the 7D.

This 15mm?
476101 Sigma 15mm f/2.8 EX DG AutoFocus Diagonal Fish-Eye Lens for Canon EOS Cameras

We're back to $600 glass again. I'm just not seeing any economically priced W/A primes out there. And again, we're talking video out here, not still photography.

Yes, it's still a 15mm times the 1.6x crop.

There are plenty of used 15mm lenses on Ebay every week going for well under $600. Many sell for $200-$400 depending on condition, and you'll also not need the latest AF version so could do with the older MF versions which go for even cheaper. Also look at the older MF lenses from other brands and buy a cheap Canon bayonet adapter.

Yes, you are still not ultra-wide...but the Tokina and Sigma ultra-wide options need not be bought for $600.

For example you can simply get the TOKINA AT-X 124 PRO DX 12-24mm F/4 zoom which now sells for very low prices if you look around - $200-400 depending on condition.

Just how much do you actually want to spend? If it is $50-150 and don't mind soft edges and degraded images, then I suppose an ad-on wide adapter might be OK.

Lots of people are using the Tokina 12-16.