Originally posted by RXrenesis8 With macro it doesn't work out quite so daintily. With a lens like this one of the primary reasons for buying it over a 50 or 100mm 1:1 macro is its greater working distance.
Yes it is. If you target the exact same pespective with a FF and 150mm lens then you get the exact same working distance as apsc and 100mm. Look at as magnification to print not lens magnification.
Originally posted by Digitalis I own a 100-300mm f/4 and it is very good, and very useful zoom range - I wonder what sigma was thinking when they discontinued it. I also own the 180mm f/3.5 APO EX Macro and again, it is an excellent lens...I doubt I will update to the current 180mm f/2.8 the difference between f/3.5 and f/2.8 isn't nearly big enough to deliver any meaningful advantage.
They probably couldn't support sales of the 100-300 and 120-300 so decided to drop the low end one as many FF shooters desire the 2.8 aperture. Was the 180 3.5 ever made in a OS version? Could be why they dropped it because with the design it couldn't be implemented. The 150mm and this new 180mm could... Lets face it Nikon and Canon are the driving forces for lens design from third parties. Nobody is designing lenses specific for Pentax except Pentax. All the versions for Pentax are just a retrofit from the Canon and Nikon designs. But doing the retrofit still has to be justified because it is an added cost. If they think to make it economical they need sell twice what would actually sell in real life they won't. More would sell for Pentax if they had a FF because Pentax doesn't have a good selection of FF lenses currently for sale. And there isn't a large enough surplus of them in the used market like for the 645D...