Saturday, 26 July 2014

AF comparison, Lumix GH4 vs Nikon 1 V3

The Lumix GH4 and Nikon 1 V3 are similar cameras. They are both the high end mirrorless cameras from Panasonic and Nikon, respectively.


Also, both cameras have some specific technology aimed to improve what has been the achilles' heel of mirrorless cameras so far: The autofocus performance during video recording, and for moving subjects.

Sunday, 20 July 2014

Making a 4K video timelapse

The Lumix GH4 (my review) can be used to create 4K videos, but there are other ways as well. One way is to take normal resolution pictures with a camera that supports time lapses, and compose a video from them.

In this example, I used the Lumix GH4 to make the time lapse, but you could use any camera which supports it, for example the Lumix GM1 or the Lumix GX7.

I first set the camera on a tripod over my table, like this:



I'm using the Manfrotto 190XPROB tripod, which is useful since the column can be set horizontally. The ball head is Benro B-2, but most ball heads can be used here.

Tuesday, 15 July 2014

Optional grip for the Lumix GM1

The Lumix GM1 is currently the smallest Micro Four Thirds camera. It has a quite trendy style, which mixes exposed aluminium with a retro look:


Despite the retro look, I am pleased to say that it does operate quite nicely. It is fairly easy to handle, although I find the rear wheel/four way controller combo to be a bit awkward to use, and would have preferred to have a thumb dial like most other cameras.

However, it really needs a better grip. And Panasonic is producing just that, the Panasonic DMW-HGR1S grip:


So what is it like?

Wednesday, 9 July 2014

GM1 vs Nikon 1 J1 autofocus during video comparison

Looking at the Nikon 1 J1 and Lumix GM1, it is clear that they are very similar:


Both are quite compact mirrorless cameras without a grip, without a flash shoe, and with fixed LCD screens. You can't put an eye level viewfinder on any of them. Both are mounted with rather similar wide angle pancake lenses in the picture above.

Also, since the Nikon 1 J1 is the very first generation mirrorless camera from Nikon, and the cheapest, it may look strange to pitch it against the Lumix GM1, which is a new, premium camera from Panasonic, widely seen as the leaders in large sensor video.

However, the Nikon 1 family of mirrorless cameras has something which Panasonic has never implemented: On sensor PDAF sensors. Panasonic have decided to rely on CDAF, which requires more image processing power to function well, but has the advantage of not sacrificing any pixels for PDAF sensors. In theory, PDAF should be able to give a much better AF-C performance, and AF performance during video recording.

You may also think that the Lumix GM1 is not a very good video camera, as it appears to be styled in a classic way. However, in my experience, it performs just as well as, or even better than, the GH3 in terms of image quality, quality of ETC video, and AF during video. So the GM1 is pretty much state of the art, except for the fact that it doesn't have 50/60 FPS 1080p video, and of course, it doesn't have 4K video.

To see how the Nikon 1 J1 camera performs in terms of autofocus, I mounted both to a Desmond Mini Dual Camera Bracket, typically used for stereo photography. The lenses are the Lumix 14mm f/2.5 and the Nikon 1 10mm f/2.8. I set both lenses to f/2.8.


For the test videos, I set the ISO to 200, except when otherwise noted. Here are the results:

Sunday, 6 July 2014

Lumix GM1 mechanical shutter

The Lumix GM1 may look like a small and insignificant camera, but in fact it has some interesting innovations within Micro Four Thirds. It has two shutters: The electronic shutter, which is faster than the first generation, but still slow enough to give some rolling shutter artifacts.

Then there is the mechanical shutter. It is of the "electronic front curtain type", which means that the exposure is started electronically, without a mechanical curtain. This is good, it means that there is less risk of shutter shock, that the shutter causes camera shake and blurry images. It is also less audible, and there is less shutter wear.

The mechanical shutter is also unusually slow. While this also keeps down the noise, it is not really a good thing, of course. Due to the slow mechanical shutter, the flash sync speed is limited to 1/50s, which is a quite poor specification. This design choice was probably implemented by Panasonic to keep the size and noise down.

The slow moving mechanical curtain is possible to record using a high speed video camera.

Enter the Nikon 1 J1. Even if it was the first generation Nikon 1 camera, and the entry model, it is capable of 1200 frames per second video. At a resolution of only 320x120 pixels, this is more of a gimmick, but it can be a fun gimmick. The two cameras are seen below, both with wide angle prime pancake lenses:


One problem with video recording the moving mechanical shutter of the Lumix GM1, is that the camera will only use the electronic shutter when a lens is not mounted. So you cannot trigger the mechanical shutter without a lens mounted. This is probably for protection, to avoid jamming the curtain blades.

However, the shutter cycles once every time you power on the camera, and this can be used to record the shutter travelling.

Thursday, 3 July 2014

Olympus 9mm: Fisheye vs Rectilinear

Olympus now has two lenses which include the 9mm focal range: The Olympus 9mm f/8 fisheye (my review) and the Olympus 9-18mm f/4-5.6 wide angle zoom lens. The first is a fisheye lens, and hence, it has significant barrel distortion. The second is a rectilinear wide angle zoom lens.

But beyond that, do they give you a different field of view? Below is the 9mm fisheye lens, with the Four Thirds version of the 9-18mm zoom:


Taking the same picture with both lenses yields these variants:


So, as you can see, even if both lenses are rated at 9mm, they give a quite different field of view. The fisheye lens is much wider. On the other hand, outside of the centre, it is quite distorted.