Lumix G 20mm f1.7 or Voigtlander 25mm f0.95
 

I'm looking at getting a fast ~50mm prime. I can't decide between these two. Obviously the Panny lens is much cheaper, but apparently there's a vignetting problem. From what I've read at f0.95 the Voigt isn't all that sharp and should be stopped down, defeating the purpose of having such a fast lens. I like the fact that there are no electrical components to the Voigt. I like being able to adjust the aperture on the lens and focus without the MF Focus Assist. What's the verdict between these two lenses? Thanks!

The Voigtländer Nokton 25mm f/0.95 is sharper @F0.95 than the Canon EF 50 mm f/1.2L USM @F1.2 and sharper @F1.4 than the Leica D Summilux 25 mm f/1.4 @F1.4 . And @ F2.8 is the resolution record holder @ over 82 lpmm . BTW it is also much sharper than the Lumix G 20mm f1.7 .

What is the distance for infinity focus when wide open? If I wanted to use it to fly on a stabilizer in a low light setting to keep folks in focus? Thanks!

I've decided not to get either. Panasonic is going to release a regular sized 25mm (50mm equiv) f/1.4 Lumix lens next month.

The Panasonic 25mm f/1.4 lens is going to be priced about the same as the Voigtländer Nokton 25mm f/0.95 lens, so you will be trading 1 f-stop for auto-focus and image-stabilization. It's a tough choice, as both AF and IS are very useful, but then so is having that extra f-stop.

Focus at the hyperfocal distance of 136.8 ft then DOF extends from 68.4 ft to infinity
Use this DOF calculator:
Online Depth of Field Calculator
http://farm6.static.flickr.com/5002/...3efcde6b_b.jpg

How accurate will the AF be wide open though? Does the GH2 offer lens calibration like DSLRs?

I have no idea about the accuracy of the AF. Hopefully it will be half-decent in low-light.

As far as I know the GH-2 does not have a user enabled back-focus adjustment like the higher end Canon DSLRs do. ( Canon 5DMK2, Canon 7D, Canon 50D )

...Also it appears that the Panasonic 25mm f/1.4 lens will NOT have I.S., so AF looks to be it's only advantage over the Voigtländer Nokton.

dSLRs offer lens calibration because they use a separate system/sensors for their Phase Detect AF systems. If you look at cutout photos of dSLRs, you can see the AF system at the bottom of the camera. As precisely made as cameras are, this separate system can be slightly out of calibration with the sensor, so my understanding is that lens calibration helps recalibrate the system.

M43 cameras like the GH2 use Contrast Detect AF, which uses the actual imaging sensor to determine if something is in focus. There is no focusing subsystem that can be miscalibrated, thus there is no need for dSLR-like lens calibration.

This is my understanding of the two systems, at least. Someone here with more know may want to chime in...

Also, I can (almost) justify having both lenses. The Panny 20 is nice and small and a good performer, perfect when you want to treat your GH2 like an overgrown point-and-shoot. The Nokton, on the other hand, is a much more deliberate tool, and looks like it will be great for more staged situations.

I've got the 20, wish I had the Nokton too...

What do you guys think of the Canon FD 28mm f/2.8? What about the FD 24mm f/1.4 in comparison to say the Voigtlander?

The Voigtländer Nokton 25mm f/0.95 is much sharper than the 24mm F1.4 and sharper than any lens tested at Lenstip.


Canon EF 24 mm f/1.4L II USM review - Image resolution - Lenstip.com
Voigtlander Nokton 25 mm f/0.95 review - Image resolution - Lenstip.com
http://www.lenstip.com/253.4-Lens_re...esolution.html

What does the Voigtlander Nokton 25 mm f/0.95 cost? I can't seem to find one.

More than the camera. I've seen them on sale for around $900-1000.

Demand exceeded supply so they're hard to come by. Only places I'd seen them listed was eBay and Adorama (pre-order, since removed). They were about $950 but due to the popularity and scarcity of them they're going for quite a bit more on eBay. There's two there now with $1,100 (US) and $1,150 (Australia) in bids. Prices will probably come down when there's more of them being made.

Wow. One of the Voigtlander 25/0.95's sold yesterday for $1,725!