Corsair Respond to Claims of K70 RGB Lighting Not Performing as Advertised
Peter Donnell / 6 years ago
It was recently brought to my attention that some users are unhappy with their Corsair K70 RGB keyboards. I recently reviewed this keyboard and absolutely loved it, but one thing that slipped through the net is that the keyboard can’t display the 16.8 million colours that are advertised, whoops! This is obviously hard to detect, but if you could display 256 levels of colour per each channel, R, G and B you would have 256 * 256 * 256 = 16,777,216 colours. A transition effect such as a slow-moving rainbow pattern on the keyboard should result in you a smooth transition between colours. Unfortunately, this doesn’t seem to be the case, as one Corsair forum user discovered.
“Testing each color was a matter of clearing every key (turning their background color to off) then making a simple fade from 255 of that color (0 on the other channels) to 0, running it over 10 seconds and counting the unique steps of brightness it produced. If a light could produce a full 256 levels of brightness I shouldn’t be able to count them in real-time. I could.
Testing each channel produced the same results: 8 steps of brightness each. 8 * 8 * 8 = 512 colors. That leaves us a whole 16,776,704 colors short of the advertised color range.”
Further users have been testing this out and come to the same conclusion on the forums. We reached out to our friends at Corsair for further details and you can read their reply below.
During development of the keyboard and prior to the release of the RGB keyboard, we came across an issue regarding the possible color combinations. In an effort to get the product out to our customers as committed, we made the tough decision to resolve the issue in a future software release as we believe our customers would enjoy the product as-is.
Here are the specifics that detail the issue:
Due to USB stack size and performance issues, we had to reduce MCU processing overhead in the best and quickest manner. The LED controller gives us greater than 8 bits of color depth but we use the 8 bits that give us what we believe to be the best color granularity. Our controller architecture provides for over 100 million color combinations out of which we select 16.8 million to display. We devised a color palette scheme to encode and compress the RGB color data and the data to select and control the “current sources” that drive the LED array. An unfortunate side effect is that it prevented us from utilizing the full color depth available from the LED controller.
We are in the process of making the necessary improvements so that we can send the uncompressed RGB data to the keyboard. Additionally, we are optimizing the data protocol and LED driver/display algorithms through the display control firmware to handle the uncompressed data, and to more efficiently program the “current sources” that drive the LED array. This should give our most “resourceful” customers an easy way to identify the data and be able to easily send standard RGB 8 bit values.
This enhancement had already been planned and will be implemented in a few weeks by the release of a software update, which will be announced and be made available to download.
Unfortunately for consumers who really care about the fine details, it feels a bit like Corsair rushed the product, or simply didn’t expect people to notice. The good news is that they’re fixing the issue and a patch is on the way, which will finally unlock the full potential of this incredible keyboard.
Thank you Corsair Forums for providing us with this information.
Image courtesy of Corsair Forums.