1. Which has better magnification, 1:2.5 or 1:5? Is 1:5 considered bad for 45-175x? Can I simply add macro adapter or close up filter to improve the situation?

2. Is it possible to tweak the settings of my G3 to match the jpeg output of Olympus? Do u have a formulae to set it?

__________________
E-PM2, PL45/2.8, 14/2.5, 45-175x, FL360, Nikon bodies & lenses.

1:2.5 is better than 1:5. 1:1 is macro.

__________________
Olympus E-3 | Olympus E-PL2 PEN | Olympus E-PM1 PEN | Zuiko ED 50-200mm f/2.8-3.5 SWD | Zuiko 14-54mm f/2.8-3.5 | Vivitar 100mm f/2.8 Macro | Carl Zeiss Sonnar 135mm f/2.8 | Konica Hexanon 50mm f/1.4 | Konica Hexanon 85mm f/1.8 | G.Zuiko 50mm f/1.4 | Zuiko 35mm f/3.5 Macro | Zuiko 25mm f/2.8 | KMZ Jupiter-3 50mm f/1.5 | E.Zuiko 200mm f/4 | Zuiko 75-150mm f/4 | Olympus EC-14 teleconverter | VF-2 and VF-3 Viewfinders | EMA-1 Mic Adapter | Olympus FL-36R and FL-50R speedlights

cyclopsphoto.ca

It's a ratio. 1:2.5 = 40%, 1:5 = 20%, 1:1 = 100%.

__________________
EM5; 9-18, PL25, 100-300 and some others.
(also, 6D + RX100)

What if I fix a raynox 250 macro adapter to the lens? What would be the magnification roughly?

__________________
E-PM2, PL45/2.8, 14/2.5, 45-175x, FL360, Nikon bodies & lenses.