Crop Factors and Nifty-Fifties... at DVinfo.net

Steven Bills · May 2nd, 2012, 03:05 PM

Hello fellow GH users!

So I've had my GH2 since July and I wanted to clear something up. I bought a Canon 50mm 1.8 EF lens (the 100 dollar one) a while back expecting to get a nice, relatively "normal" looking shot. What I got looked a lot longer than 50mm.

Well, I came to find out about crop factors, and how they affect different lenses, specifically focusing on the GH2. I found that the crop-factor for the GH2 (please correct me if I'm wrong) when compared to full frame is roughly 2X.

Therefore, does this make my nifty-fifty equal to a 100mm lens?? If so, do I effectively have a 100mm f1.8 lens (or whatever f-stop I want it to have by fixing it to my XSi and setting the f-stop there, and then taking it off and putting it on my GH2?)??

Thanks for the help!

Steven

Jeff Harper · May 2nd, 2012, 06:30 PM

Yes you have what is effectively a 100mm lens. If you're into using third party lenses, look at FD lenses instead of EF lenses, you can at least change exposure on the barrel of the lens. You can find Canon FD 50 F/1.4 lenses for under $100, FWIW.

For a 50mm equivalent the Panasonic 25mm F/1.4 is a nice lens, and the Panasonic 20mm which costs even less, as I'm sure you know, is a great value also.

Kevin McRoberts · May 2nd, 2012, 06:31 PM

You have a 50/1.8.

On the GH2, it gives an approximate equivalent field of view to a 100mm. Its max aperture is still f1.8. Its depth of field equivalence vs. full frame is about f4 (which is good or bad, depending on your needs and desires).

Don Litten · May 2nd, 2012, 06:51 PM

It's still worth having IMO. I have one that's dedicated to my Canons and one on an adapter with the aperture, dedicated to the GH2. It's still 1.8 and sharp as a tack.

The focus ring does suck though.

If you're looking for a 5o prime, see if you can find a Pentax A 50mm 1.7. You'll never look back.

John Wiley · May 3rd, 2012, 04:44 AM

Yes, you get the angle of view of a 100mm lens.

But what you have is not a 100mm f/1.8, it is a 50mm f1.8 with a cropped view. The two things are very different - a true 100mm f/1.8 would have a much shallower DOF.

Steven Bills · May 3rd, 2012, 07:49 AM

Quote:

Originally Posted by Don Litten

If you're looking for a 5o prime, see if you can find a Pentax A 50mm 1.7. You'll never look back.

Will I need any special adapters for it, and will it come out being 50mm instead of 100??

Don Litten · May 3rd, 2012, 09:04 AM

You will need an adapter and the FOV will be different. But as said before, it's still a 50mm 1.7.
I'm not sure you'll find a legacy prime in 4/3 micro and IMO, they are some of the best lenses available at any price. (My opinion)

I use them on the Canons and the GH2 and use the Canon EOS lenses on the GH2 as well.

I'm testing a Sears Zoom today that I got at a yardsale for $3.00. Looks unused and the reviews say it's good at 5.6 or below and is GREAT for Macro work. Time will tell but it opens a new world in video.

May 2nd, 2012, 03:05 PM	#1
Steven Bills Regular Crew Join Date: Sep 2006 Location: Vineyard, Utah Posts: 192	Crop Factors and Nifty-Fifties... Hello fellow GH users! So I've had my GH2 since July and I wanted to clear something up. I bought a Canon 50mm 1.8 EF lens (the 100 dollar one) a while back expecting to get a nice, relatively "normal" looking shot. What I got looked a lot longer than 50mm. Well, I came to find out about crop factors, and how they affect different lenses, specifically focusing on the GH2. I found that the crop-factor for the GH2 (please correct me if I'm wrong) when compared to full frame is roughly 2X. Therefore, does this make my nifty-fifty equal to a 100mm lens?? If so, do I effectively have a 100mm f1.8 lens (or whatever f-stop I want it to have by fixing it to my XSi and setting the f-stop there, and then taking it off and putting it on my GH2?)?? Thanks for the help! Steven

May 2nd, 2012, 06:30 PM	#2
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	Re: Crop Factors and Nifty-Fifties... Yes you have what is effectively a 100mm lens. If you're into using third party lenses, look at FD lenses instead of EF lenses, you can at least change exposure on the barrel of the lens. You can find Canon FD 50 F/1.4 lenses for under $100, FWIW. For a 50mm equivalent the Panasonic 25mm F/1.4 is a nice lens, and the Panasonic 20mm which costs even less, as I'm sure you know, is a great value also.

May 2nd, 2012, 06:31 PM	#3
Kevin McRoberts Major Player Join Date: Jun 2008 Location: Charlottesville, VA Posts: 700	Re: Crop Factors and Nifty-Fifties... You have a 50/1.8. On the GH2, it gives an approximate equivalent field of view to a 100mm. Its max aperture is still f1.8. Its depth of field equivalence vs. full frame is about f4 (which is good or bad, depending on your needs and desires). __________________ Freelance pudgy bearded lighting camera operator www.mcbob.tv

May 2nd, 2012, 06:51 PM	#4
Don Litten Major Player Join Date: Jun 2010 Location: Richmond Va Posts: 400	Re: Crop Factors and Nifty-Fifties... It's still worth having IMO. I have one that's dedicated to my Canons and one on an adapter with the aperture, dedicated to the GH2. It's still 1.8 and sharp as a tack. The focus ring does suck though. If you're looking for a 5o prime, see if you can find a Pentax A 50mm 1.7. You'll never look back.

May 3rd, 2012, 04:44 AM	#5
John Wiley Trustee Join Date: Oct 2008 Location: Byron Bay, Australia Posts: 1,155	Re: Crop Factors and Nifty-Fifties... Yes, you get the angle of view of a 100mm lens. But what you have is not a 100mm f/1.8, it is a 50mm f1.8 with a cropped view. The two things are very different - a true 100mm f/1.8 would have a much shallower DOF.

May 3rd, 2012, 09:04 AM	#7
Don Litten Major Player Join Date: Jun 2010 Location: Richmond Va Posts: 400	Re: Crop Factors and Nifty-Fifties... You will need an adapter and the FOV will be different. But as said before, it's still a 50mm 1.7. I'm not sure you'll find a legacy prime in 4/3 micro and IMO, they are some of the best lenses available at any price. (My opinion) I use them on the Canons and the GH2 and use the Canon EOS lenses on the GH2 as well. I'm testing a Sears Zoom today that I got at a yardsale for $3.00. Looks unused and the reviews say it's good at 5.6 or below and is GREAT for Macro work. Time will tell but it opens a new world in video.