Why do camera manufacturers advertise image processors but not the sensor itself?

Question

Camera manufacturers often advertise their image processors version in advertisements, such as DIGIC 6 (Canon), EXPEED 5A (Nikon) and many more. But we never see they advertise the sensor they are using. Is the image processor more important than the sensor? Wouldn't the sensor be the most significant factor in terms of determining the image quality?

IMO, image processors may help:

1. Reduce the noise when converting to JPEG. But this can be done in photoshop as well, right?
2. Improve the burst rate. But this might vary depends on the megapixel count, despite using the same image processor, take example 5DsR 5fps Dual DIGIC 6 vs 7D Mark 2 10 fps.

Am I understanding correctly?

Answer 1

This is what we call false differentiation in advertising. It applies to any marketing, not just for cameras. Think about, we have no evidence than any of this is better than the other expect for the marketing:

• Digic 6 is that better than EXPEED 4A or Venus II?
• Windex with Ammonia-D does that clean better than without? Than other cleaners?

Processors are just given names and a usually increasing number to claim improvement. There are no supporting evidence than one is better within a brand and even less across brands. For sensors, they cannot claim much superiority because most are made by Sony, the remainder are mostly by Canon, Fuji, Aptina and Toshiba (recently sold to Sony). Still, when they can claim a difference, they do:

• Fuji X-Trans CMOS II sensor
• Fuji EXR CMOS sensor
• Fuji SuperCCD EXR
• Fuji SuperCCD SR & HR
• Sony Stacked BSI sensor

Again, think about it. Is the superiority of any of these over another obvious? Manufacturers of course claim so which is why they name they new technology: To tell buyers that it is different and better.

These sensors all operate on RAW data which has more sample-depth than JPEG, so they can do a better job to apply image processing on JPEGs. Many times though you can get similar (but rarely identical) results by processing from RAW.

Answer 2

The processor is key to how the image and/or video is captured from the sensor. There's a tremendous amount of work that has to be done by the processor, even for RAW files, before the file is written to internal memory and made ready for reading out of the camera. With every camera there's a constant tradeoff between processor features, speed, and power consumption. Manufacturers are in a constant race to increase the first two will simultaneously decreasing the latter. When the processor is updated between camera model releases you can be assured that not only has the silicon advanced, but so has the firmware, in order to work those three key issues.

Speaking of firmware, one of the key, unsung features of advancing processors is the ability to update the firmware on the cameras after the sale. Fuji is the most visible example in updating their camera firmware, adding new features and enhancing existing ones. This gives Fuji customers a feeling of continuing value in the cameras they've purchased and builds a sense of loyalty. And they're not the only ones. Before Samsung decided to withdraw from the ILC market they updated the NX1's firmware multiple times, fixing bugs and adding new features. Olympus has been (lately) upgrading the E-M1 and E-M5 II firmware to great fanfare. And Nikon and Canon are not to be left out either. In order to provide this key capability the internal processor has to have enough unused storage to allow for future expansions and updates. Unlike a PC, you can't just drop in new storage to expand what originally came with the camera; everything in a camera is on a single chip (SoC).

Answer 3

Most consumer cameras use some sort of CMOS sensor, and the majority of those are made by a handful of companies (though this is changing). The major distinguishing factors are how colour separation information is handled. There are details regarding how that CMOS is configured and powered, but sensors are generally very similar in how they respond to light.

Once upon a time, Nikon was pretty vocal about their sensor tech, as they were one of the few camera companies to get custom sensors made for them in a specific fab. I think all the major camera companies own their own fabs now, though many do multiple sourcing, and contract out or own pieces of fabs instead of owning a fab outright. Anyway, none of this probably matters, as the sensors themselves are not very interesting.

So, manufacturers are going to talk about how they all take somewhat similar sensor tech and the voltages they make and actually turn that into data that can be turned into an image. Those algorithms are more important, in many ways, than how a transistor behaves when a photon smashes into it. At least, from an engineering and firmware point-of-view.

Of course, those cameras that use somewhat unique sensors, like the Foveon X3, talk that up quite a bit.

The rest of the pack distinguish themselves in other ways, because at the end of the day, whether a sensor-array-with-bayer-filter-and-support-silicon is made in Fab A or Fab B is of not much interest to engineers, or most photographers. These parts of the cameras are sort of commodity items with little to distinguish them from each-other. At least, little to distinguish them when dreaming up advertising copy. I suppose if you have a sensor array that uses a lot less power you might talk that up, especially for those power-hungry compact models. But that isn't very sexy compared with whiz-bang image processing algorithms.

Answer 4

Because it would show how little progress they did (Canon) or how well - they are using third party sensors (Nikon). Sony does talk about the sensor ;)

To your questions:

1: No - you lose A LOT of data in JPG already (8 instead of 14 bit coloring), so doing this in photohop later will not be as good. This is different from RAW or a TIFF, but JPG is very low reserves for manipulation.

2: Yes and no - burst rate is rather memory dependent as you can then queue up sensor data, it is more the throughput. Given that the processors are quite unspecified besides the name this is a meaningless marketing term anyway.