The megapixel race is back

There is no doubt that Canon and Nikon have been competing fiercely in the SLR and DSLR camera segments for many decades. Looking at the most recent decade, Canon made a head start by introducing the affordable models 300D and 350D back in the early 2000's. Then, Nikon launched the D40, which combined a small form factor, low megapixel count and a good high ISO capability. This made Nikon once again the number one in some markets.

Later, Canon replied with the feature laden and moderately priced 450D, 500D, 550D, which all topped the Japanese sales charts during the years 2008-2010.

With the most recent D3x00 series of cameras, Nikon is again a good seller, especially in Japan. Their most recent announcement, the D3200, packs a massive 24 megapixel resolution. It is worth noting that this is more than Canon have ever had in any DSLR camera.

This development can be illustrated graphically like this:

With the blue line being the Canon entry level models (300D, 350D, 400D, 450D, 500D and 550D), and the red line being the Nikon models D50, D40, D40X, D60, D3000, D3100 and D3200.

It seems that while Nikon has traditionally believed in a moderate megapixel count, they have decided to trump Canon at the megapixel race, believing that the market now wants a high number of megapixels. And perhaps they are right. After all, the recently announced Nikon D800 has generated a lot of interest, with the staggering 36MP sensor.

On the other hand, Nikon has continued their moderate philosophy with the mirrorless Nikon 1 line, with both introduction models only having 10MP. This could be to protect their DSLR line from cannibalization.

The 24MP D3200 model might be a reaction to Sony's mirrorless NEX-7 model, also sporting 24MP. In fact, their sensors might very well be related.

So, what does this mean for the Micro Four Thirds cameras? I'd say it makes it even more probable that future models will sport more megapixels. When the GH2 was launched, it upped the megapixel count of the GH1 from 12MP to 16MP. In an interview, some Panasonic professionals said that this was done largely for market reasons, not because it benefitted the images significantly.

With the competition now re-entering the megapixel race, I think it is more probable that the GH3 will come with a higher megapixel count than the GH2.

It seems that to get a camera with a moderate amount of megapixels, you must look to Nikon's professional D4 model, sporting only 16MP on a full frame sensor.

Defished fisheye compared with ultra-wide

I have previously looked at how to defish the images from the Samyang 7.5mm f/3.5 fisheye lens. Even with a generic fisheye lens profile, it is easy to defish the output images so that they appear rectilinear. But my example image does not show how wide the output image really is. To illustrate that, I will present the same image taken with an ultra-wide lens.

But first, let's compare the specs:

Lens	Focal length	Diagonal field of view
Samyang 7.5mm f/3.5 fisheye lens	7.5mm	180°
Lumix G 7-14mm f/4	7mm	114°
Olympus 9-18mm f/4-5.6	9mm	100°

As is apparent from this table, the fisheye lens has a vastly wider diagonal field of view. However, we also know that the fisheye lens has a more compresses field of view the further we get from the centre. Hence, not all of the 180° diagonal field of view can be used when defishing the image.

This can be illustrated by looking at the defishing process. Here are the same images taken with the Samyang 7.5mm fisheye lens, defished, and taken with the Olympus 9-18mm lens at 9mm:

Original fisheye image	Defished, not cropped
Defished and cropped	Olympus 9-18mm @ 9mm

The defishing process was done with Hugin, and is described in this article. In this example, I used the "orthographic" lens type, rather than the "fisheye" lens type.