Originally posted by Marc Sabatella OK, so what do you think of it? Have you tried it with and without the rear filter?
I tried it first with moon photos, then a few shots of mountains from the back yard, and some bird photos. The moon photos don't look much different than with my 400mm lens and cropping. The mountain photos were a poor choice of subject/shooting location because there's like 30-40 miles of atmosphere between here and there. The already lower contrast just gets worse. The bird photos were not terrible, but my technique is still a greater influence than the lens quality.
I haven't tried it with the skylight filter; it doesn't look like the previous owner did either.
In general, I prefer my Tokina SD 400mm f5.6 and possibly cropping, but the Tokina is about 3x the weight and twice as long. I would never travel with this lens, so I keep the Vivitar for its portability potential (unrealized, byt you never know!).