I was just playing with my test lens kit and I’ve noticed something really strange.
I need about -2.25 SPH and -0.75 CYL for close up. (Just for context)
The axis of the CYL is 170° (nearly 180° which is key for what I’m about to show you).
So looking only through a SPH lens I see directional blur (of course). Picture 1
But whenever I start to tilt the lens upwards Picture 2 the directional blur start to disappear until it is gone completely.
The same thing applies whenever I tilt my head upwards and look through the bottom part of the lens. Picture 3
I don’t know how exactly CYL works behind the scenes but I assume I was able to emulate a CYL correction when tilting the lens upwards at around (180° which is pretty close to my axis - 170°).
But why is this important? Well, because my computer screen is below eye level, The bottom part of the screen is crystal clear unlike the rest which makes it harder to work out my differentials… Any input would be appreciated, would love to start a discussion about this!