Pentax Adaptable Wide Angle Lens
Related Faq
Q
Q: Can the filter avoid the black cross phenomenon?
A
Answer: By design we can avoid the use of the filter in non-wide angle lens will not have dark corners, if your focal length is less than 24mm still may back to produce. 
Q
What is the vieweing angle of the camera?
A
Hi, thanks for your inquiry. It comes with 180° wide viewing angle. 
Q
What lens hood will work for this filter?
A
I have the 77mm version of this and I am NOT able to use a lens hood on my Canon 17-40mm wide angle once the filter is on. I haven't tried putting on the hood first and then trying to screw on the filter yet. That's not to say that all lens hoods won't work but for me it does not under the scenario described above. 
Q
Does this fit a Tamron 77 wide angle lense?
A
you said (Tamron 77 wide angle lense?) the lens info can't be right! do you have the full name of the lens. 
Q
The filter can avoid the black cross phenomenon?
A
By design we can avoid the use of the filter in non-wide angle lens will not have dark corners, if your focal length is less than 24mm may still return to produce. 
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