I assume you already have the Canon Adapter tube that would support such a lens. The tube supports 52mm filters/lens.
Most conversion lenses have a native mounting thread.
Then they use step-up rings to fit other size mounts.
What this advertisement does not tell you, is the size of the mounting threads on their lens.
This is important to know.
Based on the price, I suspect that it has a small thread size, something like 37mm. This means you will get the lens and an adapter that changes 37mm to 52mm.
Such a small mounting size can result in vignetting of your pictures. i.e. dimming or clipping of the corners.
Here is an example ad for a conversion lens. Note that it tells you the native mount size. Which in this case is 52mm. Even this lens can be fitted to other cameras by using step-up/step-down rings.
http://buyporters.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=PCS&Product_Code=19-1056&Product_Count=&Category_Code=
So, when shopping for such a lens, find out the native mounting size. If it is close to your thread size, it can be altered with adapter rings.
If it is not close to you thread size - pass it by.
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Im looking for a wideangle fisheye-type lens on ebay and im not sure which to buy or not. Could any of you aid me on what brand or lens to get? I asked 4 different stores if the lens adapter (for the wide angel lens) is actually 52mm, because thats what my camera takes. im afraid they would send me a 47mm or something because they usually dont have a pic of the adapter and never the size.
(im not trying to sell the item)
would
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=30066&item=3880158299&rd=1&ssPageName=WDVW
be a good lens to buy?

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