It seems that whenever I use the Oly 60mm Macro, the ISO increases very fast, at least faster than I am used to with other lenses. E.g. when I shot a flower in my livingroom this morning with the 60 on f/2.8 the shuttertime was 125 and ISO 2000. When I did a similar (about similar distance) shot with the Oly 45 on f2.8 the shuttertime was 100 and the ISO 800. When I repeated this with the Oly 14-150 on 60mm and f5.4 the shuttertim was also 125 and ISO was 2000. Does this have got something to do with the fact that it is a macro lens?