GH2 vs GH3 AF during video comparison

When the Panasonic GH1 was launched in 2009, it had an easy claim to fame: Being the only consumer interchangeable lens mirrorless camera that could autofocus (AF) during video recording. Since this time, the GH2 improved upon the predecessor in many ways, while retaining the same form factor. The Panasonic GH3 has a pro photo form factor, and further improves upon the GH2.

Autofocus during video is still an important feature. That, and continuous autofocus with moving subjects, have been problem areas for Micro Four Thirds. High end DSLR cameras handle continuous autofocus, e.g., for sports and wildlife, very good. This is due to using PDAF technology. Micro Four Thirds cameras, with the exception of the Olympus E-M1 so far, only use CDAF, not PDAF.

Achieving efficient autofocus during video with CDAF is a matter of having fast image processing capabilites, combined with good algorithms for interpreting the data. GH3, being the newest and most powerful of the GH-line, of course has the best potential here.

Here is a video comparison of the GH2 and GH3 both doing AF with the Sigma 30mm f/2.8 DN lens mounted. The Sigma 30mm f/2.8 is a reasonably compact, inexpensive and very good lens. Read about how the test was done below.

Are Panasonic fooling us?

The new ultra compact Lumix GM1 is marketed with a record breaking 1/16000s maximum shutter speed. That surely sounds impressive. The camera also has a brand new shutter module, using a stepper motor rather than a conventional spring actuated shutter curtain.

But is this an improvement? Let's compare the specifications with other similar cameras:

Camera	Lumix GM1	Lumix GX7	Lumix GH3	Olympus OM-D E-M1	Nikon 1 V2
Maximum shutter (mechanical)	1/500s	1/8000s	1/4000s	1/8000s	1/4000s
Flash sync speed	1/50s	1/320s	1/160s	1/320s	1/250s
Maximum shutter (electronic shutter)	1/16000s	1/8000s	1/4000s	None	1/16000s
Electronic shutter readout speed	1/10s?	1/10s?	1/10s	None	1/80s
Flash sync speed (electronic shutter)	Not possible	Not possible	Not possible	None	1/60s
Body

Upcoming lenses

Micro Four Thirds was the first mirrorless camera system launched, and now has an impressive lens lineup. Still, more lenses are arriving. Here are some news to look forward to:

Kipon HandeVision IBELUX 40mm f/0.85

The lens with the strangely capitalized name is to be released late February 2014, and, according to the marketing, it will be the fastest lens ever. That is probably not true, as, for example, the Carl Zeiss Planar 50mm f/0.7 used by Stanley Kubrick to record the movie Barry Lyndon is still faster. But it will certainly by one of the fastest lenses available.



The lens is completely mechanical, requiring to be focused manually. The price will be quite stiff, just north of US$2000. It will be released for the Micro Four Thirds, Sony NEX, Fujifilm X and Canon EOS M mounts. The lens weights no less than 1.2kg, illustrating just how much glass there is in it.

GoPro Hero 3+ Black Review Part 1

Nowadays, the most selling camera unit is an action camera, the GoPro Hero 3+. This can be commented in many ways:

• The compact camera and consumer camcorder markets are shrinking. This is due to competition from below with smart phones, and competition from above with compact, but advanced mirrorless system cameras. Why buy a compact camera, if your smart phone can do just as well? Due to the shrinking traditional camera market, this action camera has become dominating.

• There is little competition in the action camera market. In test after test, the GoPro Hero 3+ Black Edition is crowned the king. Even as Sony and Panasonic launches competing cameras at a lower price and with interesting additional function, e.g., optical image stabilization, they cannot dethrone the GoPro Hero.

Here is the GoPro Hero 3+ Black Edition camera unit, with the waterproof housing.



In the picture above, I have used an optional tripod mount adapter, which allows you to put the camera on a normal tripod with a 1/4'' stud.

What framerate to use in videos?

Excellent video is one of the reasons to use Micro Four Thirds cameras, especially the ones from Panasonic. Some come with different framerate choices, so which to use?

First, here's an overview of the existing alternative framerates. I have outlined the choices for full HD 1920x1080 resolution only. For lower resolutions, there may be more framerate selections available:

Framerate	Panasonic	Olympus
24 fps	GH3, GM1, GX7, G6	None
25 fps	All PAL area cameras	None
30 fps	All NTSC area cameras	All
50 fps	PAL area cameras: GX7, GM1 (only interlaced), GF6 (only interlaced), G6	None
60 fps	NTSC area cameras: GX7, GM1 (only interlaced), GF6 (only interlaced), G6	None

As you can see from the table above, Panasonic gives you much more choice in terms of which framerate to use. All current Olympus cameras only have one single choice: 30 fps.