View Full Version : Crop Factor


Dennis Vogel
December 27th, 2013, 12:52 PM
I understand how the crop factor for the GH3 effectively doubles the focal length of a traditional SLR lens making a 25mm lens into a 50mm lens. What I'm not certain about is whether that holds true for lenses made specifically for micro 4/3 lenses.

In other words, does the Panasonic Lumix G Micro 4/3 LEICA 25mm f/1.4 lens work as a 50mm "normal" lens on a GH3? Or is it really a 25mm wide angle?

D

Bob Richardson
December 27th, 2013, 03:08 PM
Micro-four-thirds lens manufacturers do not engage in any conversion/tricks in stating the focal length, fortunately.

Any name-brand "25mm" lens on the GH3 is indeed a 25mm focal length, and can be considered roughly equivalent in actual field of view to a 50mm lens on a full-frame camera like the 5D.

Kevin McRoberts
December 27th, 2013, 03:10 PM
A 25 is a 25 is a 25... due to varying crop factors amongst camera bodies, lenses are always listed by their actual focal length instead of their "full frame equivalent," which would just confuse everyone the minute they tried to use it on a different sensor.

Dennis Vogel
December 27th, 2013, 05:04 PM
Kevin and Bob,

Thanks for the replies. Things are as I thought they would be. A 25 is a 25 but works effectively as a 50 on a GH3. I want a "normal" 50mm prime so I'm going with the Leica 25mm f1.4.

D

Bruce Foreman
December 27th, 2013, 05:46 PM
Dennis,

You'll find that to be an excellent choice. If you use it as we had to use the "shifty fifty" in the 1950's on until zooms became popular, you should find it to be one exceptionally useful and flexible lens. Plus it has an outstanding reputation for sharpness, very good contrast, and good color tones...Even wide open.

I have one of these and love it.

Dennis Vogel
December 27th, 2013, 10:44 PM
Bruce,

I've read good things about here and elsewhere. Glad to hear it is as good as it sounds.

D

Ron Fabienke
January 2nd, 2014, 10:12 PM
Hold it steady, not stabilized but a sweet lens. I have one as well.

Dennis Vogel
January 5th, 2014, 10:28 PM
Rob, thanks for the tip.

I sprung for it last week. It arrived on Friday but I haven't had a chance to try it out yet. With its speed I'm hoping lack of stabilization won't be a problem, especially for day time use. I'm hoping it will open up some opportunities in low light that none of my other Panasonic lenses can deal with at reasonable ISOs.

D