A while ago I asked advise on this board from people using various fish-eye lenses, which of them was better, becuase I planned to buy a suspiciously cheap one from ebay.
Here is the discussion
Now I can say that I made an experiment: my cheap (about 30$ including delivery) Bower fish-eye macro arrived and I even made few shots with it. Here is my impression.
This "lense" resembles a big fillter consisting of several parts and is to be used on top of a normal lense. I use it with Canon 400D camera and Tamron 18-200mm (it's already a bit extreme, but works fine on travel and studio). The fish-eye's thread size is 58mm and to fix it with Tamron's 62mm thread I use an extension ring (7$ more).
Altogether the construction can be autofocused, which is interesting. Because when I tried to use this fish-eye (with another extension ring) on my Canon5DMarkii and (don't laught, please) Canon L 50mm1,2 lense, it couldn't focus at all, even manually.
The minuses of using this cheap fish-eye compare to decent and more expensive real ones are the following:
- the image becomes small, because it crops a piece out of a crop.
- the quality of image made with a decent lense is, of course, higher in general.
But I discovered pluses, too.
- on some angles my cheap fish-eye makes a funny natural blur effect, at the same time a part of an image still remains sharp. At this case the image is quite large (all croped matrix is used) and almost doesn't requre post-processing.
- without much risk it gives the possibility to try fish-eye effect before making desision if you really want to spend money on an expensive new lense or you don't use it too often.
So, my opinion - it's not bad to have such a toy. Variety inspires.
Here is how the lense looks and how it shoots :) Some of it's images are already approved on DT. Next time I'll try to do more :)