« on: Today at 04:28:50 PM »
That's... sort of the opposite of what I was trying to explain, heh!
The projected image gets physically larger, hence acting like a zoom if you were to collect the light projected on to a 24mm x 36mm selection at the centre of the projection - the entire image is enlarged, you'd be collecting much fewer photons but the image is optically "zoomed in" and very sharp, sort of like a variable aperture zoom
Ok, then what's the different between your way vs say, extension tube? tele-converter? APS-c sensor? cropping in PP?
Either way you are cropping into the image circle, digitally or optically, which will inevitably reduce sharpness. If optically cropping does not reduce sharpness when a 2x TC won't give you any worse image quality compared to no TC, which is not true. You can't divide resolution without facing softness.