ericmark
01-05-2016, 04:23 PM
I bought this Opteka 0.2X Super Wide Fisheye Lens adaptor second hand from a lady I know it's not that often I need more than my 18mm with standard lens and I have been stitching with both CS5 and Hukin both reasonable so was doing this on the cheap cameras standard lens is 52mm so fitted straight on.
However focus seems to be a slight problem I have found centre is spot on but to the sides not very sharp. However realised that often it will not fit direct onto camera lens often one needs an adaptor ring so thought maybe too close.
Tried fitting the circular (not really circular) polarising filter between the adaptor and original lens this seems to work well and up to now can only test with inside photos and it seems better. What I want is to test outside just wonder if able to reach infinity?
At 18mm the result is a circular image zooming out to 35mm I get full frame with any item at sides curved as one expects. Zoomed out to 55mm the results compare with lens without adaptor set to 20mm.
So looking at rectangular image no corners cut off it about doubles my angle of view. Getting the fish eye round look then about 4 times area but this is really just an effect rather than any good for general photography.
Camera is a Pentax K10D host lens is the standard Pentax SMC DA 18 - 55mm. CCD size 23.5 x 15.7mm
I have a fixed 28mm lens for full frame camera, but 55mm filter thread, however holding the adaptor against the lens there is about the same corner cut off as with the 18 - 55mm set at around 28mm so corner cut off is not due to host lens being designed for a cut down sensor.
It does what I want but a little upset about focus outside where edges were not sharp. Not simply focus picture of local pond very noticeable but picture of crib in camera club and seems nearly A1. Since lady has a Canon not Pentax I do wonder about the space between adaptor on host lens and if adjusting this using empty filter rings may correct it?
Has anyone else used these adaptors?
However focus seems to be a slight problem I have found centre is spot on but to the sides not very sharp. However realised that often it will not fit direct onto camera lens often one needs an adaptor ring so thought maybe too close.
Tried fitting the circular (not really circular) polarising filter between the adaptor and original lens this seems to work well and up to now can only test with inside photos and it seems better. What I want is to test outside just wonder if able to reach infinity?
At 18mm the result is a circular image zooming out to 35mm I get full frame with any item at sides curved as one expects. Zoomed out to 55mm the results compare with lens without adaptor set to 20mm.
So looking at rectangular image no corners cut off it about doubles my angle of view. Getting the fish eye round look then about 4 times area but this is really just an effect rather than any good for general photography.
Camera is a Pentax K10D host lens is the standard Pentax SMC DA 18 - 55mm. CCD size 23.5 x 15.7mm
I have a fixed 28mm lens for full frame camera, but 55mm filter thread, however holding the adaptor against the lens there is about the same corner cut off as with the 18 - 55mm set at around 28mm so corner cut off is not due to host lens being designed for a cut down sensor.
It does what I want but a little upset about focus outside where edges were not sharp. Not simply focus picture of local pond very noticeable but picture of crib in camera club and seems nearly A1. Since lady has a Canon not Pentax I do wonder about the space between adaptor on host lens and if adjusting this using empty filter rings may correct it?
Has anyone else used these adaptors?