My budget for lenses isn't much more than $1200... I love the look of the Nokton along with the fact that it'll fare well in low light, but I want to get a decently fast wide lens as well. Is there any reason why I couldn't just plop a .45x adapter on the end of this lens and have myself a 50mm and 22.5mm equivalent in one lens...
Yes it would be very soft especially in the corners, and the distortion would be horrible.
Have you tried several wide angle adapters with the Voigt 0.95?
try a VERY high end 0.45x wide angle adapter like this one: http://16x9inc.com/shop/cart.php?m=product_detail&p=34
Yes. All soft at the edges. Sony, Canon, you name it. They are not designed for large sensors.
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