Tag Archives: resolution

Rumour: Pentax to level with Olympus on super-resolution

8 Feb

A rumour was published on digicame saying that Ricoh/Pentax would shortly announce that all cameras coming out later in 2015 and beyond will have a sensor-stabilisation based super-resolution mode. This led others to repeat the previously rumoured 144MP figure that could theoretically be obtained from a 36MP Bayer sensor (as may be used in an upcoming Pentax full frame camera) using such technology. The rumour also states that Pentax/Ricoh’s approach is different from Olympus’.

It currently seems the main drawback of Olympus’ technology is that the required series of images takes considerable time to be recorded.


Why high resolution cameras don’t need an AA filter

17 Dec

Disclaimer: Unfiltered truth ahead.

Digital cameras used to have a problem, which was that their lenses were so sharp that images would show moire or aliasing if there wasn’t an additional anti-aliasing or low-pass filter placed directly in front of the sensor to add a small amount of blur. Side effects of this filter include a small reduction in light transmission and a slight distortion of the colour distribution.

As camera sensors got to around 16MP APS-C or around 40 MP full frame, it became apparent this problem wasn’t so much of a problem any more. Glass quality generally wasn’t good enough to still cause moire and other aliasing at this tight packing of Bayer array and photosites. The lenses themselves served as AA filters, and throwing in an low pass filter on the sensor only made images blurrier, without any particular benefit. So some smart executive or engineer at Nikon said, “let’s ditch the thing and see if our customers like it”. And the customers came, and they saw that it was good, and they bought it.

Around the same time, some Pentax execs likewise came together and said unto each other, “let there be unwavering sharpness”. But knowing full wele that the Nikon gods had spread their bets across two models, one with and one withoute AA filter, the good sirs of Pentax did likewyse, and thus there came to be the K-5 II and IIs, made in the D800E’s image.

So there you have it: the story of why you can buy a D800E or K-5 IIs without regret. And how, as an engineer, you can do something for very good reasons and completely fail to communicate this to the customers. Probably because upper management told you to keep your trap shut about the sharpness of the lenses. And the fact that the Ricoh GR and Fujifilm X100S take sharper pics than your monster-tea-bagging SLR.

So there you have it: the reason you can leave that K-3 AA simulation switched off, save battery power, and never worry. Woohoo!

The more megapixels, …

6 Oct

…the sharper your lens has to be.

…the more accurate your focus has to be.

…the faster your shutter has to be OR

…the better your image stabilisation has to be (IBIS, OIS or tripod).

…the bigger your hard disk has to be.

…the faster your computer has to be.

Nikon releases two cameras, Canon, Pentax and Olympus users panic, and Sony chuckles

25 Feb

People probably thought Nikon wasn’t serious when it relased the D3200 – after all, noise levels for the 24 megapixel sensor were laughable, especially at higher ISO settings. The chickens also did not stir when the D5200 came out – same megapixels, better signal/noise ratio. Apparently, the writing was not on the wall until the announcement of the D7100. OH NO! You don’t mean they can use that same sensor in a sturdier, pro-looking body, OH MY. OH MY GAWD, WE ARE ALL GOINGS TO THE GALLOWS NOW. That pretty much sums up the response from the Canon (yup), Olympus, and Pentax camps. Meanwhile, Sigma kept playing with its own toys in a corner, blissfully unaware that this other Bayerverse existed.

It’s clear that Sony can send the rest of the bunch scurrying at its whim. Release a new sensor, give it to one of the other camera manufacturers and watch how the rest get jealous like little children. That little bit of control must feel good for Sony after having boldly switched its own entire line-up to what it calls SLT – a technology whose time seems to lie in the distant future, if at all ever.

But it remains to be seen how many customers can actually fork out enough money to pay for lenses that actually take advantage of this new-found resolving power on APS-C. Already, one photography magazine has fallen into the trap of comparing the D600 (35mm format) with the D5200 (APS-C) of the same resolution without ensuring that the lens(es) used exceeded the resolving power of each sensor, concluding that the D600 retains more detail, especially at high ISO. If the lenses used had been explicitly stated, a critical interpretation of the outcome might be possible. As it stands, the test was useless.

Window of opportunity for Canon 7D, Nikon D7000 is closing

11 Feb

While DxOMark tests still give the sensor of the 7D a slight edge over the cheaper and more basic 650D, a recent test in ColorFoto (3/2013) shows the RAW files of the 650D to resolve more fine detail.

Similarly, the Nikon D5100 outperformed the D7000, albeit by a much smaller margin. It’s to be expected, though, that the currently arriving D5200 will obsolete the D7000 more conclusively. This is already reflected even in DxOMark scores, which is remarkable not only because DxOMark does not take into account the much higher resolution of the new Toshiba-made sensor in the D5200, but also because DxOMark reviews are usually delayed by many months after the introduction of new camera models (not to mention that some models are seemingly never tested at all).

What’s clear is that those who care about image quality should focus on buying recently released camera bodies rather than be fixated on premium models. For camera manufacturers, the implication seems to be that camera design should be made more modular and synchronised, so that bottom and top APS-C lines can be updated simultaneously, which could stop newly released cheaper cameras from cannibalising sales of fully featured bodies. Pentax for several years has avoided any significant design alterations of its flagship APS-C body, which hints at just such a modular strategy.