Translate this blog into your language

Showing posts with label Canon Engineers Explain Their EOS-R Mirrorless Camera Project. Show all posts
Showing posts with label Canon Engineers Explain Their EOS-R Mirrorless Camera Project. Show all posts

Friday, January 25, 2019

Canon to announce entry level EOS-R camera plus Non L RF zoom lenses




After announcing the EOS-R camera and RF lenses in Q4 of 2018, Canon is expected to follow up with an entry level EOS-R model and some less expensive zoom RF lenses this year.

This is to increase the user base of the full frame mirrorless cameras and gain some economies of scale. Already, Canon is the best selling mirrorless camera brand in Japan and capturing a larger customer base in North America is the next goal.

My readers know I am not a fan of the EOS-R camera in its current form. A major firmware release is expected the first quarter of 2019 in addition to a slew of new RF lenses. There is little to indicate what is included in the new software right now but suffice to say it cannot fix the major 'problems' like a single card slot, lack of a thumb wheel, around 3 fps burst rate in Servo AF with Dual Pixel RAW files, unimpressive battery life, etc.

If and when Canon announce their EOS-1D full frame mirrorless camera, I will take another look at their offering.

Tuesday, December 18, 2018

Canon Explains The Larger RF Mount On The EOS-R Mirrorless Camera




The following article is an excerpt from Canon explaining the larger RF mount on the recently announced EOS-R camera. It is translated into English from Japanese by Google and may not read like an article written in English originally.

I am The Wildlife Ho-tographer, not an optics engineer. The EOS-R is not a camera I will buy for my equipment bag in its present configuration. You can read my post on why I came to this conclusion.


In 2018, a 35 mm full size mirrorless camera attracted a lot of attention. Nikon and Canon have entered so as to follow independent Sony, and it is now clear that Panasonic and Sigma, which received L mount license from Leica next year, will introduce their own full size mirrorless camera.

The companies that are new entrants this year appealed were the physical structure of the lens mount. In addition to the short back focal length unique to mirrorless cameras, the word "large aperture" was repeatedly heard. It does not mean that the open F value of the lens is bright, it means that the opening of the mount part is large.

Increasing the opening of the mount is not a zakkori story that "big is a good thing", it is nothing other than having a merit to pursue lens design. In this paper, we will deliver the content of technical briefing sessions that Canon made for stakeholders.

The optical designer reads the lens composition diagram (cross section) and reads how the light passes through the lens, saying that it is "beautiful" not "beautiful."

According to the optical designer of Canon, it is said that the following three points are the main judgment criteria because "it is optically good" in what "beautiful" is said.

· The symmetry of the optical system is high before and after the diaphragm
· The refraction of the light is gentle
· the large ball and the small ball are lined up in good balance

Perhaps there are a few who viewed other companies' lens designers as well as Canon in the same way as interview articles in small journals. Anyway, this viewpoint becomes the basis for considering the merit of the large diameter mount.

Let's look at an example that a large aperture mount will help with good lens design. From the previous three points, please keep in mind that "If you bend the light a lot, strong aberrations will occur".





First, set up 3-piece configuration as a reference lens. Instead of having a long back focus, there is no mount opening to disturb the light flux. The vertical bar at the right end of the figure is the imaging surface (film / image sensor) and the left is the subject side.

Below is an image of a case where design was advanced with a small caliber mount. A mount with a small diameter obstructs the light flux, and it is necessary to put the concave lens in the rearmost portion so that the light reaches the periphery of the imaging surface. First, this sudden spreading method generates aberration. And it will be necessary to adjust the lens on the front side to balance.

Then, the number of components increases, the lens barrel becomes longer and longer, and in the first place the lens configuration is not good because of the above reason. It is said that it is in a "vicious cycle".

The image using the large diameter mount is below. If the third lens from the front of the reference lens is lowered to the imaging plane side and the diameter is increased, aberration correction can be corrected straightforwardly.

Many lenses are made up of 10 or more existing products rather than 3, so I think that the actual story is not so simple. Nonetheless, it would be felt that it would be easier to design optically straight lenses if the mounting aperture was adequate.





Subsequently, as an example of Canon, it is a configuration diagram of "EF 35 mm F 2 IS USM" for single lens reflex cameras and "RF 35 mm F 1.8 MACRO IS STM" for mirrorless cameras.
In the above EF lens, the lens was placed on the front side with respect to the reference lens. In the lower RF lens, since there is no mirror box, we placed a lens with the same effect at the end. As a result, the RF lens has a shorter overall lens length from the imaging surface.

Until the RF mount is determined to have an inner diameter of 54 mm

Initially, Canon also considered to realize a 35 mm full size with the EF-M mount of the APS - C mirrorless "EOS M" series, but satisfactory results were not obtained, such as no performance aimed at . And since the system becomes large when unnecessarily increasing the mount diameter, we actually designed multiple lenses, decided to 54 mm while looking at the balance of optical merit and size, the strength of the camera and so on.

Then the numerical value of 54 mm inside diameter resulted in the same inner diameter as the single lens reflex EF mount, and the designer of the RF mount felt "There was a foresight ahead of 30 years before the birth of EOS".

Oh yeah, it is now Canon that appeals the value of 54 mm like this, but at the product release of "EOS R" we did not announce the concrete numerical values ​​(54 mm inner diameter, 20 mm flange back) on the stage. Before that half a month ago rival Nikon announced the full size mirrorless Z system, it would not be unrelated to the extensive appeal of the numerical value "mount inner diameter 55 mm · flange back 16 mm".

However, the merit of "large aperture mount + short back focus (short flange back)" that two companies appeal is that the degree of freedom of lens design will increase to the last. The idea is basically common.

Also at the press conference of Photokina following the announcement of the two companies, Sony, which is five years ahead of the full size mirrorless market, says, "Do you need a large-diameter mount for large aperture high performance lens?" → "The answer is" No "There is also a scene that rewards one arrow in hot topics.

However, in this context, Sony refuted because it was pre-introduction to introduce the high-end super telephoto lens "FE 400 mm F 2.8 GM OSS" that Sony α Mirror less will sport coverage of sports! And it seems not to be able to receive simply. However, when I heard this, the inner circle was excited that in the 21st century again "sparks falling down" may be seen.

So at the end we got off to some extent from the topic of Canon, but like this, the full size mirrorless market in 2018 was an opportunity to remember that it was hot and humorous.

Monday, October 22, 2018

Canon Engineers Explain Their EOS-R Mirrorless Camera Project


EOS-R camera Design Engineering team

My readers know me as The Wildlife Ho-tographer. I have been using Canon gear for over 30 years but will not be buying the EOS-R camera. You can read my post on how I came to this conclusion and follow my travels on Facebook and Twitter, see my equipment bag and works on MichaelDanielHo.com

When I read parts of the interview below, I had sympathy for the engineering team. They were given an impossible task. Satisfy millions of current Canon DSLR users and attract millions more new mirrorless buyers and innovate. Oh, by the way, you are limited to a much smaller body to work with.

All the EOS-R innovations mentioned below can be applied to current DSLR if the engineers are given the same money and time to work on the present and future models. Considering Canon is the largest photographic company in the world and the last to announce a full frame mirrorless camera, the result is nothing to write home about, especially for serious and professional photographers.

Like I said before, why be a Johnny-come-lately follower, when one can be a real innovator. All the current full frame mirrorless cameras from the Big 3 look alike. They all use a separate line of lenses. There is No technical reason why a full frame mirrorless camera need a new mount different from a full frame DSLR mount. It is a marketing decision to have the new full frame cameras be smaller to appeal to a larger user base. Faced with a new size limitation, all features and functions have to adapt to the new reality. 




The engineering team tasked with developing the EOS-R full frame mirrorless camera system gave an interview to DP Review recently. Below is an excerpt of their discussion.

The launch of Canon's EOS R gave us a chance to talk to a group of the engineers involved in the project. The company put forward an engineer from each of the main parts of the development process: physical design, optical design, UI design and overall product design. They talked of being given more freedom than ever before but also of the need to build on the EOS system's strengths.

A new, short and wide mount

Canon has been consistent across its launch, when it's said that the important announcement isn't the EOS R, specifically, or the fact that there's no mirror, but in what the RF mount allows them to do.

Manabu Kato sums up the freedom they've gained in terms of optical design: "people who've been working on lenses for a really long time have, with this new system, been able to make lenses like the 28-70mm F2 comparably easily, compared to how they had so many challenges in the past."

"By having [more] data being transferred between the camera and lens...you can improve the autofocus, metering and image stabilization performance"

As well as allowing more ambitious optical designs, the RF mount also adds data bandwidth, moving from eight communication channels to twelve. "During shooting there's a massive amount of data going between the lens and the camera, so making sure that was smooth was another challenge," says Kato. "By having that huge amount of data being transferred between the camera and lens, you can improve the general performance in relation to autofocus, metering and image stabilization. And you can also add features such as the control rings on the lenses."
"You can also use DLO without any problems," he said. Digital Lens Optimizer - Canon's name for digital lens corrections - previously required that the camera look up the data in a database, meaning that camera firmware needed to be updated to accommodate new lenses. It's now supplied in real time by the lens itself, so there's no need for a look-up step.

Video, as well as stills

This real-time data flow allows the use of Digital Lens Optimizer and distortion correction in video for the first time. And it's clear that, despite the EOS R's comparatively modest specs in that area, Canon has done a lot of thinking about the needs of video shooters.

"Getting rid of [the mode dial] was a big decision that required a lot of consideration"

"In relation to the optical system, we gave consideration to focus breathing*, and also aperture control: you can change the aperture in 1/8th stops," says Kato. "also the Nano USM, it's very quiet and quick: the first time in an L lens."

Difficult decisions

Trying to accommodate the needs of video shooters ended up leading the removal of the camera's mode dial, says Koji Yoshida :

"if you have a mode dial then the [exposure] settings will be the same for both stills and movies."

The decision not to offer a mode dial on the EOS R was not taken lightly.
"We consulted with a lot of different people and talked about this a lot, and decided to have different settings this time," he says. But it's clear this isn't a decision made lightly: "[The mode dial] is a function that's been common in the past, so getting rid of that was a big decision that required a lot of consideration," said Shintaro Oshima.

"There was a lot of internal discussion about this point," concurs Yoshida.

The challenge of legacy

This tension between novelty and legacy is a constant theme of our conversation. "Our aim was to carry on the traditional parts of EOS but then bring in new innovation at the same time," says Hironori Oishi :

"our biggest challenge was making this look like an EOS camera with just a single glance, you can see that it's an EOS camera, based on the traditional styling of the EOS cameras. And also the feeling, when you hold the camera - as soon as you hold it in your hand, you know it's an EOS."

This extended to the user interface, says Yoshida:

"the challenge we faced in terms of the software or the interface was making sure that it's got the same basic controls as an EOS: to carry on that operability that EOS users are used to, then also implementing new elements into that design at the same time."

The answer was to blend features from Canon's existing live view and DSLR experience:, he says :

"We used the mirrorless AF modes but we also also included features from the 5D Mark IV AF, like Expand AF area and large zone AF: this is the first time this has been introduced in a live view camera from Canon."

Opportunity for innovation

The solution to these tensions seems to have been to look for opportunities to innovate while maintaining continuity: something made clear in the challenges of maintaining EF lens compatibility. Despite the EF mount already being fully electronic, Kato says :

"it was difficult ensuring that compatibility. But we think that's a big plus for the system."

Tellingly, the team looked for ways to add new features. "We also achieved the control ring adapter which brings additional value to EOS lens users," says Kato: "The same applies to the drop-in filter adapter: it gives added value to those who already have EF lenses. We wanted to make sure that we looked after our current users of our EF lens system."

"The control ring adapter brings additional value to EOS lens users...the same applies to the drop-in filter adapter"

Oshima stresses that the need for continuity didn't hold the new camera back, though :

"another focus was the low light limit performance. That's a point of evolution from the EOS cameras."

"Another focus was the low light [autofocus] limit performance"

This eye for an opportunity to innovate is perhaps most clearly seen in the way the EOS R, unlike any other mirrorless camera, closes its mechanical shutter when shut down. "we wanted to protect the sensor as much as possible from dust and light hitting the sensor," explains Oshima :

"The light coming through the lens affects the sensor in the long term. The color filter array and microlenses and also the photodiodes can all be damaged by light [if the sensor is always exposed]."

To then protect the shutter blades, the camera stops its lens down and displays a warning not to leave it facing towards the sun, without a lens cap. "The aperture cannot be closed completely, so that message is kind of a safeguard," explains Kato: "We're kind of proud of the fact that with a simple idea, we've been able to increase value for customers."

Just the beginning

As usual, no one was able to discuss future products. When asked whether there was any chance of an APS-C RF-mount camera, Oishi was suitably non-committal: "we're thinking about it, but we can't answer in detail," he says. But the individual engineers did all discuss what they were looking forward to.

"We want to surprise and astonish you, so please expect big things"

"It gives more structural freedom in terms of design, because it doesn't have a pentamirror", says Oishi. "I'm excited about improvements in Digic image processor and functions that create more value and make easier to use," says Yoshida. But it's optics specialist Kato who seems most enthused:

"This is just the start of the system," he says, talking about F2.8 zooms and other possibilities, before settling on a broader-reaching point: "We want to surprise and astonish you, so please expect big things."