Again, trying to normalize on what things look like when shot with a 35mm sensor is irrelevant. If you have two camera phones with similar sized sensors and foc

Again, trying to normalize on what things look like when shot with a 35mm sensor is irrelevant. If you have two camera phones with similar sized sensors and focal lengths, an f1.5 lens is almost a full stop faster than an f2 lens. Yes, the resultant SNR is worse on a small sensor but fstops are a ratio of focal length to aperture size not a measure of DOF or SNR. The f1.5 lens will have narrower DOF and let in more light. F1.5 is an accurate way of marketing the lens. Like I said before, trying to normalize different aspects of images and the resultant quality by trying to make f-stops something they aren't only confuses and obscures what is actually happening and prevents sensible discussions of camera systems. The 35mm equivalent focal length is used just to give an idea about FOV. I wish they would just give us the angle of view in degrees instead. Then maybe people would stop trying to mangle what fstops means in regards to DOF, the amount of light the sensor sees, SNR etc. Compare similar sensor systems, stop trying to cram one into the other.