Lightfield Photography Part 2 (Lytro Illum)

Lytro Illum  (Photo credit: KoFahu meets the Mitropa)

I talked a lot in the previous part of this article about how light field photography works and why it's useful. In this part I'm going to focus primarily on the enhancements to the Illum which is the recently announced second generations Lytro camera. I'm going to focus mostly on why the enhancements in the Illum are potentially useful even for serious photographers.

As I opined before, too much emphasis is put on the Lytro's ability to refocus. The fact of the matter is that this ability to refocus comes at a cost. I've often referred to the first generation Lytro as a great proof of concept and it was; but it wasn't without some fairly significant faults. Those faults caused a fair amount of consternation in some circles and are likely causing Lytro some headwinds right now. If you read any of the comment sections associated with articles written about the Illum you'll know what I'm talking about.

In my opinion Lytro made a mistake in their marketing of the first generation camera. That mistake was in focusing too much on the megapixels captured while avoiding at all costs any mention of the resolution of exported 2D images. On the one hand this was understandable. 1.1 megapixels stopped being an impressive resolution a decade or more ago. The limited resolution was also at odds with their desire to present the Lytro camera as a premium product at a premium price. In addition it was generally difficult to get a good quality picture even at the 1.1 megapixel export resolution. Pictures were often soft and colors were subdued and muted in my experience. It was rare that I ended up with a final image that wasn't mediocre at best. This is not a good outcome for a camera that has as its major selling point the ability to refocus so that you can avoid bad pictures.

In addition there were aspects of the hardware that bugged me. The biggest was the LCD. The small dimensions were inevitable given the industrial design but the quality was less than stellar. It was dim and had poor viewing angles which made the camera difficult to use. My other hardware related gripe is the lens cap. It never stayed on as the magnet was weak. Consequently I was always losing it. Having said that, I loved the concept and the technology and have been looking forward to Lytro's second generation camera for awhile now.

Enter the Illum, a product that on paper promises to be a significant improvement over its older sibling. The design is slick and modern looking with a definite nod to digital SLR's.

The lens is a permanent part of the body and features an impressive 30-250 mm zoom range with a constant F/2.0. What does that mean in layman's terms?  Basically you get everything from a fairly wide angle to an 8x zoom with excellent light capture across the entire range. The ability to capture light is important as it relates directly to the quality of the picture. This is true of any camera but even more so in the case of light field photography.

Our eyes and brain are a great team. They work in tandem to create a visual experience that is generally smooth and glossy. Normal camera's don't have a sophisticated human brain doing real time processing which is why it can be difficult to get a good picture.

Getting a well focused image requires an appropriate depth of field, (AKA focus point) and either a whole lot of light so that the exposure time is short or a tripod and long exposure time. The Illum doesn't have the human brain but it does have a whole lot of smarts and technology built in that should make it easier to take good pictures.

The first advantage the Illum has over most cameras is that 2.0 F-stop rating. The thing to know about F-stops is that the lower the number the faster the lens. Put another way, as the number decreases the lens is capable of letting in more light because it can open wider in a given period of time. Normally that is a bit of a trade off as more light means a shallower focus range. Large F-Stop numbers mean that most or all of a picture you take will be in focus while small F-stops mean you'll have a steadily narrower focus range as the F-stop number decreases. This isn't a problem for the Lytro as capturing the light field allows an image to be rendered that is in focus over a much wider range of distances. In effect you get the wide depth of field advantage of a high F-Stop but with the high light capturing capability of a much smaller F-Stop which should translate into better quality pictures in situations such as sporting events where fast shutter speeds are needed.

The Illum's 40 mega ray censor will capture roughly four times the light rays that the original did. This in turn translates to 4 mega pixel 2D images. That 4 mega pixel export number is likely a compromise that provides reasonable output in a wide range of scenarios. Macro images and images a very limited depth of field could likely be rendered at higher resolutions with good results as the light rays captured would originate from a much narrower depth of field range and thus provide more data(light rays) at a given focus depth with which to render an image. Of course the inverse is true as well. The wider the available focus range the less data will be available at a given focus point to render from. This may explain why Lytro images can look soft. Lytro basically has two choices when they don't have a lot of data at a given focus point. They can interpolate between available light rays or look at light rays that may provide additional information but not be ideal for a given focus point. In all likely hood I suspect they do a bit of both.

The LCD may be the biggest upgrade of all though. As I mentioned above, the original Lytro's LCD was... sub optimal. The dimness, limited viewing angles and small size meant that I was often shooting blind. The Illum's much larger screen and ability to tilt will inevitably lead to a better experience. How much better remains to be seen but I'm fairly optimistic. My Cannon EOS 70D has an LCD that rotates and moves in a lot of ways that the Illum's won't but it won't tilt back without rotating it 180 degrees out from the body. This provides a similar but not identical experience and after trying it out I think I'm going to like the Illum a lot. The best shot is often taken from lower than eye level, particularly when you're tall as I am. Being able to look down and easily see the framing for the shot is very useful.

The UI on the original Lytro was spartan. That was because of the tiny touch screen and  limited processing power. The Illum's Snapdragon 800 processor has four cores which will enable a much better user experience. One feature shown in the pre production models is the ability to visualize what will be within the refocusing range. That alone is worth the price of admission. It was always frustrating to me when I'd take a picture, load it into the Lytro management software and then not be able to refocus as I wanted.

Of course the big question is will all of this be worth four times what the original Lytro cost? I pre ordered mine and as an owner of the first generation camera I got an additional ~$250 discount. That was good enough for me to pull the trigger so I'll be able to explore first hand what this camera does in another month or two. I have some thoughts on the pricing that I'm going to reserve for the next part of this series.

Related Articles:

• Lytro's Illum Can Do Something No Other Advanced Camera Can
• Lytro's new Illum camera brings light-field tech to pros (and it could change photos forever)

A Brief Overview of Lightfield Photography Part One

The following is an update of an article I wrote for Make Magazine. A much slimmed down version with some great graphics appears on pages 60 & 61 of volume 38. The online version which resembles what is below much more closely can be found here.

The Lytro camera has been around for a couple of years and the feature most people seem to talk about is the ability to fix or change the focal point of a picture after it has been taken. But that isn't the whole story; in fact it’s just the tip of the iceberg.

Traditional cameras, whether digital or analog capture a scene from a single point of view. Photoshop and similar software enable amazing things to be done to these images but it’s unlikely that any amount of post processing will give photographers the ability to slightly change the perspective of an image, change its focal point or render it in 3D. To do those things you need to have captured the entire “light field”. The light field is made up of additional data types that include not only the color and intensity of a light ray but also the direction it came from. In addition the light field is all of the light rays that enter the camera, not just those that are focused on a traditional camera’s sensor or film to create a single point of view 2D image.

The first generation Lytro captures the light field by directing the light rays that enter the main lens onto an array of over one hundred thousand micro lenses. The micro lenses in turn direct the light rays onto a  6.5 x 4.5 mm CMOS sensor with the ability to capture eleven million light rays arranged in a 3280 by 3280 grid. Each micro lens utilizes a roughly ten by ten pixel portion of the CMOS sensor.

Capturing the light field is only the first step. The next step is to generate an image that can be viewed. Doing this has been described as “ray tracing in reverse”. To explain what this means I’m going to describe how pinhole cameras work, traverse briefly through ray tracing and finally explain the Lytro rendering process. All three have two things in common. First there is an observer viewing the scene and second, the scene must somehow be rendered onto a screen that the observer can view...

In a pinhole camera light rays pass through a hole in the front of the camera and appear on the opposite surface as an image that is upside down and reversed. The back wall is essentially a screen. If you were inside the camera with your back to the pinhole lens you would see the projected image in front of you.

In the case of my crude illustration above try to imagine if you can; that the scene object is a cactus. This and all other images can be clicked on to get a higher resolution version. Sadly the quality of the drawings does not improve.

In ray tracing a scene is described mathematically using geometric shapes, textures and light sources. A point outside the scene is selected that represents the position of the observer and an image is generated from the perspective of that observer...

Ray tracing differs from the pinhole camera example in three ways. First, the scene does not exist in the real world and has to be rendered. Second the “real” scene is in front of the observer rather than behind and finally since the scene is virtual, the image on the screen needs to be rendered. This is done on a pixel by pixel basis. “View” rays are cast out into the scene for each pixel and the color of the pixel is calculated based on the objects and light sources each view ray hits while traversing the scene. Sending view rays from the observer greatly reduces rendering time as only the portions of the scene visible to the observer need to be calculated.

In the case of the Lytro we have the stored light rays that describe the scene captured when the picture was taken. In order to project an image onto our screen and generate an image a focal point needs to be chosen. Given the selected focal point, the Lytro software uses the stored light rays to render the image. This is ray tracing in reverse in that the rays projected onto the screen to generate an image have their origin point within the scene rather than having been projected from the observer and through the screen into the scene.

To review, in ray tracing the scene is rendered by shooting view rays out from the observer and through the screen while with the Lytro the scene is rendered by shooting light rays captured in the scene back onto the screen.

A recent addition to the Lytro Library software is the ability to create 3D images. This ability demonstrates another advantage of capturing the light field. As in the pinhole example imagine yourself inside the Lytro camera. Scooting around would give you a slightly different view of the external scene. The data needed to render those transitions is part of the captured light field and can be used to generate 3D renderings of the captured scene. A pair of inexpensive Anaglyph glasses is all you need. It’s easy to export the images as JPG’s so that they can be viewed by anyone with Anaglyph glasses. Below is an example based on a picture I took at the OK corral with my first generation Lytro.

One downside of the Lytro camera is the lack of a published API for image manipulation. Lytro uses a proprietary image format and while a lot of work has been done to reverse engineer it and create software to manipulate images as I write this there is no comprehensive cross platform API or software available for working with LFP’s (Light Field Picture files). The best resource I’ve found is “Lytro meltdown” (http://optics.miloush.net/lytro/Default.aspx) which tends to be Windows centric but contains a lot of useful information.

Light field photography is still in its infancy. Prices were initially high and the results underwhelming but things are starting to change on both fronts. The first generation Lytro camera can now be had for under $200.

The thing I’d most like to see is a comprehensive cross platform open source library that can be used to manipulate and manage LFP files. The Holy Grail would be software capable of taking a raw Lytro file and rendering images.

The recent announcement of Lytro's second generation Illum camera has some interesting technical and marketing implications that I'll talk about in the second part of this article.

Related Articles:

• The Clever Thinking Behind Lytro's Gorgeous New Camera Design
• In Brief: Lytro's Illum Looks More like Mirrorless than Monocular
• Lytro Goes After Prosumer Photographers With New Camera

A Short "Yes I'm Alive" Post

Here we are three plus months into 2013 and I haven't made a single post prior to this one. I always have questions percolating around in my mind and fresh new opinions that I want to share but for whatever reason this hasn't been the right forum. For the most part I've been making short posts to Google Plus when I have something I want to share. G+ continues to be a great outlet with a lot of engagement and an ever growing user base. Of course if you listen to most of the press you'd think it is Google's biggest failure to date.

Speaking of Google, I have had a longer piece sitting on the back burner for the past few months that looks at where Google makes their money. The obvious answer is of course advertising but its interesting to look at a breakdown of where that money comes from and what the associated costs are. When I did that I discovered something interesting. I'm not going to say more about that right now but it's easy enough to figure out if you're willing to look at their financial statements. I may even dust off what I've already done and post my analysis sometime soon. When I started the final 2012 numbers weren't in yet and they should be now.

Kindle Fire HD 8.9 Initial Thoughts

I've had my Kindle Fire 8.9 HD for awhile now but haven't commented on it for a couple of reasons. The first is that it arrived between my Acer Chromebook and Nexus 4 and was kind of crowded out. The more important reason though is I haven't been using it much.

That situation has improved recently but I'm still more than a little ambivalent about it. Don't get me wrong, the hardware is nice for the most part with the screen being excellent. The software is an evolutionary step up from my original Kindle Fire but easy enough to navigate and well suited to Amazon's business model of making it easy to buy and consume content from the Amazon store so what's the problem?

I try to be technology agnostic but there are a some things I don't want to do without. At the top of that list is GMail with several other Google. You don't get the Google apps with the Fire even though it is running Android under the Amazon User Interface. Rooting the device is an option but based on my experience with rooting my original Kindle I'd prefer not to go down that path. Things tended to break and apps become unreliable.

Google provides apps for iOS, they need to be in the Amazon app store as well. I've debated recently which company is to blame for the absence though so I won't take any more time on that topic here. Note you will see a picture of the Play store on some of the screen shots. This is a result of a half hearted attempt to work my way around this problem. It exits immediately when launched. :-(

I also purchased the Amazon Kindle HD Case which is kind of expensive but nice. It is included on the images below.

Production values have gone up a bit as I'm now using my Nexus 4 rather than the Palm Pre+ to take pictures.

The placement of the micro USB port is sub optimal when using the optional Kindle Cover

One minor nit with the case is that the back tends to slide when it is used as a stand on smooth surfaces which causes the Fire HD to collapse slowly to the table.

The cover is sturdy and well made. This is the front

As the caption on the first picture above mentions the Kindle Fire is not without design flaws. The placement of the micro USB and HDMI ports is sub optimal when the Fire HD is used with the case. Ideally they should have been put on the opposite side from the volume and resume buttons which are on the right hand side of the picture above.

This is the back of the cover. Note the speaker grills

The case fits the Fire like a glove but is reasonably easy to attach and remove. It's available seven different shades. This is "Ink Blue".

You can see the shiny in the picture above. I only occasionally find it distracting

The screen automatically dims when the case cover is closed and battery life is very good when the Fire HD is in standby mode. Battery life in general seems good as I can go several days of casual use between charging.

Can anyone name the film?

You can pretty much use the Fire HD as a mirror in many  lighting situations. In spite of that the viewing experience is actually  good the majority of the time and when the lighting is dim it looks amazing. To be fair, as you'll see in some of the pictures below it's really no worse than the iPad 2.

Overall performance is excellent with the included apps but I have noticed some sluggishness and lag on apps I've purchased such as "Air Harp" and "Archipelago". I'm inclined to blame this on the apps themselves since most things work fine.

The discounted AT&T 4G LTE plan is a nice first year feature if you purchase the 4G version. It will be interesting to see if it is available after the initial year. It really isn't cheap on a per megabyte basis if you compare it to AT&T's larger data plans so I think there is a decent chance AT&T will extend the offer.

Fire HD Versus iPad 

The iPad is often referred to as a ten inch tablet when in reality the screen size is only 9.7 inches. The Fire HD 8.9 is exactly the same width as the iPad when in the landscape orientation with the difference in screen size between the two devices being explained by their very different aspect ratios.

The Fire HD nearly covers the iPad 2

In the picture above I've placed the Fire HD on top of my iPad 2. You can see that they are much closer in overall size than you might expect given the difference in screen sizes

Detail showing that the width of the screens is pretty much identical as are the Bezels

In fact they are identical width wise both in terms of their overall size and bezel's.

Side by side, notice the restrictiveness of the screens is very similar

The size difference is explained by the 16:9 apsect ratio of the Fire HD 16:9 which leads to a shorter screen than the iPad's which has an aspect ratio of 4:3.

The iPad's retro aspect ratio means you're basically going to have the same experience viewing most movies on either since you'll get large black bands at the top and bottom of the iPad which will not be the case for the Fire HD. The iPad 2 is much lower resolution as well. This isn't an issue with the iPad 3 or 4 as they have approximately the same screen bit density as the Fire HD.

Conclusion

The Kindle Fire HD 8.9 is a nice but somewhat flawed experience. 

If you're only interested in consuming stuff from the Amazon ecosystem then chances are you'll be pleased. If you want a full Android tablet experience and you aren't willing to root the Fire HD than the Nexus 10 is a much better bet though you would miss out on instant streaming video if you are an Amazon Prime member.

Overall I'm OK with this purchase but a bit disappointed. I only have myself to blame though as I knew what I was getting into.

I don't mean to imply the Fire HD is bad. It really is a nice piece of hardware and you get a lot for your money. I just don't like having to live without GMail, Google+ and the rest of the Google app suite.

Nexus 4, Worth It?

A month or so back I was reading about how great the Nexus 4 was and feeling like somebody had punched me in the stomach. I'd planned on being one of the first "in line" but got distracted at work and ended up missing out. When the second batch went on sale I was determined I would emerge victorious. Little did I know how difficult and frustrating the next several hours would be. Everything started out fine. I added one of the 16GB models to my cart and clicked the Proceed link. That is where the first part of this story should have ended. When I clicked the proceed button I was informed my cart was empty. Then I was informed Google was out of stock.

I'll cut this part of the story short and jump ahead three hours when I finally managed the nearly impossible task of getting one into my cart and convincing Google to let me give them my money. I was exhausted, pissed and relieved. After that experience I had very high expectations. 

My previous Android phone was a first generation Droid X. I remember hearing a lot of people question why anyone would want a phone that large. It turns out a lot of people did in fact want a larger phone which lead to the iPhone 5 being about the same size as the Droid X. 

The Nexus 4 is a bit longer and a bit wider than the Droid X, but still very manageable. Here's a picture of the two phones side by side for comparison.

Front: Droid X and Nexus 4

Other than the size the thing that strikes me the most about the Nexus 4 is the lack of ornamentation on the front. This simplicity is in large part due to Google's decision to not sign an exclusive selling agreement with any carrier. Maybe Google also discouraged LG from putting their logo on the front. Honestly I wouldn't have minded a little ornamentation to help visually differentiate the top from the bottom when the phone is in its case because if the notification light isn't flashing it can be difficult.

The back of the Nexus 4 is a lot more interesting with both the Nexus logo and LG making an appearance.

Back: Droid X and Nexus 4

I almost bought the even larger Galaxy Note 2 but changed my mind when Verizon's online ordering system told me I'd lose my unlimited data plan. Worse still it tried to push me towards a 2GB plan for only ten dollars a month less than I'm currently paying. This was enough for me to lose my last bit of loyalty to Verizon.

Pros and Cons

Resolution wise the state of the art in phone cameras hasn't advanced much in the past two and a half years as both the Droid X and the Nexus 4 sport 8 megapixel cameras. Picture quality on the Nexus is better in my limited testing but not profoundly so. Where the Nexus 4 really wins over the X is Video quality. 1080p versus 720p is a big jump in quality.

Comparing these two phone in any area other than camera resolution would be a bit of a joke. The X was a great phone in its day but the state of the art hardware and software wise has advanced significantly and its would be a bit like comparing a horse to a 1964 and a half Mustang. Both are elegant and functional in their own way but the Mustang will get you to your destination faster and more smoothly.

The first thing I noticed about the Nexus was how fast it is. It loads apps up almost instantly and scrolling is essentially real time all the time. I can't think of any other way to describe the experience other than to say its "Apple like". 

The screen is clear and sharp with excellent viewing from almost any angle.

Battery life is good with a single charge lasting me comfortably through a day of moderate use with plenty to spare. 

There are some things I don't particularly like but they've all been discussed at length elsewhere so I won't spend much time on them here other than to note that in a phone this inexpensive some compromises are going to be made. The one thing I will mention is the glass back. Sure, the sparkles are kind of cool but they don't justify going with a design feature makes the phone more fragile. I'll also say that the complaints about the lack of LTE don't make much sense to me. Based on the bandwidth I get at my house I could burn through my entire 5GB monthly data plan in a bit over an hour. LTE certainly has some advantages over HSPA+ but they aren't all that significant right now given the limited availability of LTE and the additional battery drain.

The biggest non phone bonus is having the freedom to pick my carrier and move at will. Right now I'm using the T-Mobile $30 plan which gives me unlimited text, 5GB of data and 100 minutes of voice. Tacking on taxes and tethering would bring the total to about $50 which is way below what Verizon and the other carriers in the US charge for similar plans.

Conclusion

I've had the Nexus 4 about a week and a half now and so far I'm loving it. It's not only a great value price wise it also compares well with any other phone on the market right now including Apple's latest offering. The only downside? Good luck getting one. Google is sold out again with not indication of when more units might be made available. Apparently neither LG nor Google had a clue that this thing would be such a big hit. 

My only big concern long term is hardware support. What happens if my phone has some sort of failure? When you buy and iPhone you know the answer to that question. 

To be fair the Nexus 4 is just over half the price of an equivalent unlocked iPhone 5. That kind of savings doesn't come without something being lost. I'm basically gambling I never need that platinum support that I didn't pay for.

So in summary and to answer the question posed in the title of this post the Nexus 4 is an excellent phone that would be a great deal if you could buy one and based on my early impressions it was even worth the three hours of frustration I went through to buy mine.  Fret not though if you didn't get one because the way these things work there will be a new Android phone out in the next few months that will match or surpass the Nexus 4. 

Related Articles:

• Nexus 4 Google Play stock exhausted again
• Google UK head: Sorry for Nexus 4 debacle (but it's LG's fault)

No Amazon Phone For Me!

Amazon shipment (Photo credit: enno)

There have been rumors for awhile now that Amazon is working on a phone. It's probably safe to assume that an Amazon phone would run Android since that is the case with their tablets. Having recently acquired a Nexus 4 I'm not going to be in the market for awhile but if I were I wouldn't be interested in an Amazon phone.

Amazon is Android without Google. No native GMail app, no Google navigation app, no Google+, etc. Amazon's ecosystem makes this kind of work on tablets but that ecosystem advantage gets much smaller on a phone where people are less likely to want to watch a movie or partake of Amazon's other offerings. The use case for a phone is different than a tablet and a lot of things Google brings to the mobile experience play particularly well on phones. Not having those capabilities present on a phone would make for a less satisfying experience.

This problem would be mitigated somewhat if the browser that came with Amazon's tablets weren't so bad. In my experience it tends to be slow, prone to crashing and offers very poor support for GMail and Google+ in particular. GMail is kind of usable but Google+ is nearly useless. Its just not a good experience.

I'll be the first to admit that I'm not your typical user but I think a lot of people would miss Google's navigation software and be frustrated by the lack of choice in the Amazon App store. 

The answer to this problem is obvious. Amazon needs to get Google to make their apps available on the Amazon App site. I suspect there are roadblocks on both sides of this equation though.

On the Amazon side is a desire to want to control the user experience. A more cynical way of putting this would be to say they want to have a clear field when it comes to monetizing their mobile devices. Bringing Google into the picture makes that impossible. Google is a profitable company for a reason. 

On the Google side there may be frustration with Amazon using Android for free and essentially giving nothing back to Google. Google can't be happy with Amazon's decision to change the default search engine on Fire tablets to Microsoft's Bing either. Google and Amazon don't compete in all the same markets but there is a growing overlap and that is likely a detriment as well.

On the other hand Google has good support for iOS and Apple is clearly a competitor as well. Google does this because it makes business sense which is why I suspect they would come to an accommodation with Amazon if an attempt were made.

Which brings me to the conclusion that the real holdup here is Amazon. 

If I'm right than Amazon has a clear path forward if they really are planning on releasing a phone. I won't say that the Google Apps being missing would kill an Amazon phone but I do believe it would have a sizable impact on sales and reduce the viability of such a product. 

A smart phone without Google apps just isn't as smart as it should be. When you're competing with Apple, Google and a bunch of other well established players its not a good idea to be running the race with your legs tied together.

Acer Chromebook C7 With 16GB Of Memory?

Most of my posts have both business and technical elements with a tilt towards the business side. Today I'm going to turn the dial all the way over to geek and expand a bit on my Acer C7 review while also exploring the (unofficial) memory expansion options of the C7.

First of all a word of warning. You void your warranty by opening the case of the C7. If you take a look at the bottom of the C7 you should see a sticker like the one pictured bellow. It basically tells you you're SOL if you open the case and anything bad happens later. Don't say you haven't been warned by me, and Acer if you choose to explore further. 

To Boldly Go..

Below this sticker is a single screw you'll need to unscrew in order remove the bottom plate.

When you do you'll see something similar to this.

The hard drive is on the right and the memory is in the center. The C7 comes with a 2GB SoDIMM pictured towards the top and center. If you look just below it you'll see an additional slot that is empty.

I recently decided to upgrade my main laptop/computer from 8GB to 16GB as the cost with tax and shipping from Amazon was only $70. I'd had the C7 about a week when I received the 2x8GB SoDIMM's and decided to see if the C7 would work with that much memory.

Above you'll see the C7 with the 8GB SoDIMM's installed. Below is a closeup.

You can click on these images to see a bigger version but its probably not worth it in most cases since the quality is fairly low.

The next step was to power the C7 up and see if it would work. I first tried ChrUbuntu Linux. The results were what I was hoping as if you look towards the upper left corner of the following photo you'll see a number that starts 16 and has a lot of additional digits after it...

I'd had a less than stellar experience with this distro when the C7 had only 2GB. By default it doesn't setup a swap/page file and opening Chrome with a half dozen tabs was enough to cause the OOM (Out Of Memory) killer to kick in and start freeing up memory in its usual brutal and unforgiving way. Creating a swap file solved that problem but the system was sluggish which isn't a surprise. Any time you have to start using your hard drive as additional memory performance will suffer. I could have chosen a more light weight window manager but didn't bother since I was fairly sure I'd be upgrading the memory soon.

ChrUbuntu is a 64 bit distro/kernel and it had no problem recognizing and using all 16GB. Having that much RAM in the C7 didn't magically turn it into a high powered workstation but it did improve the user experience since it no longer needed to swap to the hard drive.

Next up I toggled the C7 to boot into Chrome OS and restarted.

I'd noticed before that the mini Linux distribution at the heart of Chrome OS is 32 bit. For the non technical this means that it will normally recognize less than 1/4th of the 16GB I had installed. There is some "magic" that can be done to work around this limitation. It's called "PAE" or "Physical Address Extension" and  what it does is allow the 32 bit Linux kernel to use all of the memory that is installed. This does come at a small cost in lost performance. How much of an impact depends on a lot of different factors but about 5% is typical.

I had no clue if the Chrome OS Linux kernel had PAE enabled but once the C7 came up and I logged in I was able to confirm that it does...

The impact of the additional memory in Chrome OS was smaller since its already very light weight. Opening tabs seemed a bit quicker but that could have been my imagination.

Once I'd verified that the 16GB config worked in both ChrUbuntu Linux and Chrome OS I pulled the 8GB SoDIMM's and put them in my main laptop. That left me with 2x4GB for the Chromebook. Not surprisingly both operating systems work fine with 8GB as well.

It probably doesn't make a lot of sense to upgrade a C7 to anything more than about 8GB since the underlying hardware isn't really up to supporting applications that would need those kinds of memory resources. You can get to 8GB at the cost of your warranty and around $40.

The additional memory does seem to extend battery life a bit. I don't have any formal measurements on this though.

Additional Thoughts

The C7 is an inexpensive work horse and surprisingly customizable. Don't like the hard drive? Invest in a solid state drive and replace it. Want more than 2GB? No problem, can do. Want to run something other than Chrome OS on it? Very doable. I haven't verified Windows 8 but I'd be surprised if it can't be made to work and Ubuntu Linux is already a given.

I'd really like to see an extended life battery. Three to four hours is OK, but I've gotten used to being able to go five hours or more before I have to find a wall outlet. It's not a fatal flaw though given the very modest price of the C7