Quote Originally Posted by neuroanatomist


How was it too far? Your Tamron is a 17-50mm, meaning you should be testing at 50mm and about 4 feet. For the 70-200mm at 200mm, that's 16 feet from the chart. Also, I'm not sure where the 300% crop comes from...



I may have a misconception about the "% crop" terminology. I was trying to match the photos given in the directions by showing +/- 20mm range. When I'm trying to fill my screen with that, PS is telling me I'm zooming in ~260% or so. Maybe "zoom" doesn't equal "% crop"??? [^o)]


When I "zoomed in" the photo I took 4ft away @50mm with Tamron 17-50mm, the photo is very pixely (I shoot raw, only convert to jpeg at the last stage from the tiff files).


I shoot with a 300D Rebel, and it's 6mp isn't quite up to the cropping challenge


Tamron 17-50mm shot 4ftaway.


[img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.39.83/Tamron-17_2D00_50mm-_4000_50mm-4ft-away.jpg[/img][img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.39.83/Tamron-17_2D00_50mm-_4000_50mm-4ft-away-_2800_extreme-zoom_2900_.jpg[/img]








These are for Canon EF 70-200mm f/4 USM shot 10ftaway (couldn't go 16. I hit the wall [:^)])


[img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.39.83/Canon-EF-70_2D00_200mm-_4000_200mm-10ft-away.jpg[/img][img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.39.83/Canon-EF-70_2D00_200mm-_4000_200mm-10ft-away-_2800_extreme-zoom_2900_.jpg[/img]