How much resolution is lost with keystone?

[ks-man]

My projector got installed yesterday and the projector that was chosen for me does not have any lens shift. This means we need to use the keystone adjustment to fix the image and due to the size of the screen and placement of the projector the keystone adjustment is pretty massive (almost the max it will allow). The projector has a native resolution of 1920x1200. Is there any way for me to measure the amount of degradation of the image?

I'm trying not to get too hung up on this as the image still looks very nice but it is pretty disappointing to know that my current image is softer than it otherwise could be.

[Joko]

I recall researching this and as I remember the degradation can vary depending on the projector. I have no answer but your best bet is a post on projector central.

[ks-man]

I'm actually now thinking that my projector does have lens shift. The installer tilted the projector down to the screen but reading this it sounds like I'd be better off having it pointed straight and trying to manually "shift" the image vertically down. I'm pretty new at all of this but from reading the net it sounds like if this is possible it is much better than angling the projector down and using keystone.

Does that sound correct?

[Joko]

I believe lens shift is a better option, yes. I will defer to more knowledgable folks, but I would definitely use lens shift over keystoning.