about oly 45/1.8mm ane PL 25/1.4mm

I personally don't stagger my focal lengths by more than 100% unless there is no way to avoid it. Personally I like going roughly every half a stop in angle of view.

So for me an ideal setup is 12, 17, 25, 42, 63mm. Since they don't make all of those, I am happy with 12, 17, 25, 45, 75.

As of right now I have the 14/2.5, 17/2.8, 25/1.4 and 45/1.8. My next purchase is the 12/2 and then maybe the 17/1.8 or 60/2.8 macro. I need something wider angle.

That said, specifically on the question of 25/1.4 and 45/1.8, one is not really a replacement for the other. The 25/1.4 is much more versitile, especially indoors. My 25/1.4 tends to be more of a walk around lens for me if I think I am going to be taking people pictures (14 or 17 if I am shooting more architecture or landscape). I'll bust out my 45/1.8 for specific portraiture or more detail shots and it a wonderful lens that I could not live without, but it probably gets a third of the action that my PL25/1.4 gets.

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