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06-02-2011, 12:58 PM   #1
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Fisheye lens

Are those $50 0.5X lens adapters any use at all? I'd like to experiment with wide angle but don't really want to invest any money in a new lens right now.

06-02-2011, 01:56 PM   #2
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QuoteOriginally posted by kinsale Quote
Are those $50 0.5X lens adapters any use at all? I'd like to experiment with wide angle but don't really want to invest any money in a new lens right now.
I have tried them using an already wide lens, such as a 24 or 28mm.

the two I tried both suffer badly from lateral CA, and also barrel and moustache distortion.. to the point where I would consider them only for 4x6 print use.

However, and here is the real catch. I have been playing lately with pentax photo lab and CA correction in Pentax Photo Lab. It works differently than corel PSP X3 which is my usual processing package.

In Photo Lab, it rescales each color with different magnification re-alligning it tro properly correct the CA and retain detail sharpness in the corners and edges.

I need to go back and do some more testing, but it may be that with correction applied as a first step in PP, I may have a different conclusion. It would require a lot of PP for each shot however.
06-02-2011, 03:10 PM   #3
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Paper weights (Opteka). Even the "good" (Canon) ones.
06-02-2011, 03:13 PM   #4
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QuoteOriginally posted by SpecialK Quote
Paper weights (Opteka). Even the "good" (Canon) ones.
+1 - they suck!

06-02-2011, 04:42 PM   #5
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They suck on still pictures. If you want wide pictures that suck, they're just the thing. They're OK with video. But they are NEVER worth US$50.
06-02-2011, 05:30 PM   #6
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If you really want a low cost fish-eye lens, be prepared for a little compromise. The 12mm is quite wide, but it is fixed focus (not really much of a problem) and not as sharp as the Pentax 10-17mm. This is the cheapest true fish-eye lens that I know of. Sells around $100 on ebay.
The Strange Case of the 12mm Fisheye
06-02-2011, 06:16 PM   #7
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QuoteOriginally posted by gp1806 Quote
Mine, branded as Vemar, is misaligned and won't reach infinity focus, even after I shaved down the T2 adapter, even at f/16. I can use it for fishy close-ups and nothing else. Well, as a paperweight too. It has just three Waterhouse (fixed) stops: f/8, f/11, and f/16. I recommend it only for masochists.

The most reasonable fishy deal is the Zenitar 16/2.8. Slightly fishy on an APS-C sensor; it defishes to ~12mm. It's notably faster than the DA10-17 at 16-17mm (f/2.8 vs f/4.5) and pretty damn sharp. AFAIK it can still be had for a bit under US$200. The DA10-17 is slower, much more flexible, and rather more costly.

Last edited by RioRico; 06-02-2011 at 06:23 PM.
06-02-2011, 09:11 PM   #8
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There's the Spiratone or Kenko (and other brands) 180 degree fisheye adapter, also known as a 0.15X fisheye adapter, also known as the eye of Hal from 2001. That can sometimes produce good results. Others report better luck with it than I've had, in truth.

06-02-2011, 09:50 PM   #9
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QuoteOriginally posted by Nick Siebers Quote
There's the Spiratone or Kenko (and other brands) 180 degree fisheye adapter, also known as a 0.15X fisheye adapter, also known as the eye of Hal from 2001. That can sometimes produce good results. Others report better luck with it than I've had, in truth.
Oh yes, the Kenko 180. I've mounted it on a few short zooms. It produces a full-circle image below ~40mm, and a frame-filling image above ~60mm. (The exact results vary between host lenses.) I've found that the host needs to be stopped WAY down, and even then the image edges aren't exactly sharp. But it's not as terrible as the 0.5x adapters.
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