Saturday, March 31, 2012

Lytro Camera, Three Hardware Things I'd Change

Into the Lens

I've had my Lytro camera long enough to have a fairly good understanding of its strengths and weaknesses. This time around I'm going to focus on my three biggest hardware related complaints.

To be fair, I love the industrial design of this product. It is sleek, attractive and easy to use. Lytro did a great job of putting together a next generation camera that doesn't sacrifice ergonomics and functionality in favor of aesthetics. There are some kinks however.

First off is the lens cover. I like the basic idea but it suffers from two major flaws. First of all the magnet that is supposed to keep the lens cap attached to the front of the camera is weak and the cover comes off very easily. This kind of defeats the purpose of having a lens cap in the first place. The second problem is that there is no way to attach the lens cap to the camera when the camera is in use. I was going to bevel one corner of mine and drill a small hole so I could attach a piece of string that would attach it to the wrist strap but I've already lost the lens cap for the second time.

My second complaint is the LCD. Yes, it's low resolution. I'm actually OK with that. The problem is its very dim when viewed from above and less than stellar when viewed from the sides or above. This makes it difficult to frame shots since the LCD is the only way to see what the field of view is for the picture you are taking. This problem is compounded by the fact that the LCD stays on when the camera is plugged in for download and charging. It takes a long time to download and process images from the Lytro camera so I generally wander away from my Mac and return hours or days later. In the meantime my Lytro's LCD has been on the whole time. I may be imagining it but I think it has gotten even dimmer as a result. Hopefully Lytro will update the camera firmware to automatically turn off the LCD after a few minutes.

My final complaint is also about the LCD. The touch screen isn't as sensitive as I'd like, particularly when I'm in creative mode. I'll get a shot framed and need to adjust where the focus is and have to touch the screen multiple times to get the right focus. Meanwhile the hand holding the camera has drifted in part due to the pressure I have to exert on the screen and thus I have to readjust.

If I had to pick only one of the three to fix it would be the LCD. That really is the cameras Achilles heel right now from a hardware perspective.

Into the Lens (Photo credit: Wikipedia)
Enhanced by Zemanta

Wednesday, March 28, 2012

More Lytro Thoughts

Lytro photo of Stone River by Andy Goldsworthy...

In my last post I spent a bunch of time talking about CCD's as a possible limitation on the capabilities of future Lytro cameras. As I posted in the comment section of that entry it turns out this shouldn't be an issue. Lytro CEO Ren Ng discussed CCD's in his 2006 PhD thesis and according to Ng higher density CCD's were unlikely to be a cost driver in the future.

It turns out that the Lytro camera is using a CMOS sensor rather than a CCD. I'm not knowledgeable about this technology but apparently the primary up side is faster transfer of data off the sensor. That can be a significant advantage for a product that wants to be an easy to use point and shoot. I've been impressed with the Lytro's cycle time between pictures and this probably helps explain why it is so fast.

Another potential problem I mentioned was optics. Based on an interview with Lytro Executive Chairman Charles Chi that I link to in the "Related Articles" section below this may not be an issue either. Chi notes that

What we're trying to capture is rays of light, and the more of them we have, the more interesting things we can do for imaging. There's a lot we can do for lens correction, aberration; we can do much more dramatic 3D effects, refocus effects.

The implication here is that while its nice to have high quality optics it isn't vital. Some amount of correction can happen as part of the post processing.

Given all that I think I'm finally keying in on the fact that the real strength, and weakness of the Lytro camera is the software. On the plus side much of the cameras functionality is in software so there is a good chance that those of us with the first generation product will feel like we have a brand new camera a year from now. On the downside, the computation that is required to make the Lytro tick is non trivial and may explain at least in part why some decisions about the cameras design were made.

For instance, that very small display? Yes, it is in part a side effect of the form factor but you might notice when you flick to the right to look at a picture you've just taken that a certain amount of time passes as the camera does something, about four seconds in fact. This happens once per picture so far as I can tell after which the preview happens instantly. My guess is that some amount of processing has to go on before the camera can do its fancy refocus trick. Something similar happens on import to my 2008 iMac. That process takes about a minute per picture. So, a higher resolution LCD might mean longer wait times for previews. If the time taken scales linearly it would take sixteen seconds if the display were 250 x 250 pixels which is four times its current resolution but still very modest by modern standards. It's easy to see that taking that much time wouldn't fly in a consumer product.

Would a GPU help? It seems like it would but right now I don't have enough of an understanding of the CPU in the current Lytro camera or how applicable the kinds of functions that GPU's are good at would be to light field photography. My instinct says very but that isn't my field or area of expertise so I could be way off.

Lytro photo of Stone River by Andy Goldsworthy at Stanford (Photo credit: Steve Rhodes)
Enhanced by Zemanta

Saturday, March 10, 2012

Lytro, What Is The Future?

CCD from a 2.1 megapixel Hewlett-Packard digit...

This entry is going to be a combination of what I think I know about how the Lytro camera works and what that might imply for Lytro's future products. The information contained here was gleaned from various on line sources and conversations I had with several Lytro employees at a recent photo walk for first camera owners. Employees were happy to answer questions about the current model and enthusiastic but understandably tight lipped about future plans/products so there is no inside information here. Any errors are solely my own. I in no way represent the company other than being a satisfied and very intrigued customer and early adopter.

I've had several ah ha moments recently about the Lytro camera, the technology behind it and what all that means to the future. The first big aha moment was when I figured out that it uses a standard CCD which is the technology at the heart of all digital cameras. For those who don't know, a CCD is a piece of silicon that translates the light that comes into a camera into digital values that can be stored and processed by computers. CCD stands for "Charge Coupled Device" and if you click on the first occurrence of CCD above you can learn all sorts of interesting things about how they work.

When Lytro talks about their first camera they prefer to refer to "magarays", or the number of light rays they capture. There are multiple reasons for this. First this is a very different camera from anything we've seen before and the terminology really does need to change to make understanding the differences easier to explain. The other reason is that the actual 2D product that comes out at the end of the process isn't very impressive right now; more on that topic later.

The eleven megaray number comes from the fact that Lytro is using an eleven megapixel CCD. Most smart phones have between five and eight megapixel CCD's so from that perspective the Lytro camera is actually a bit ahead of the game. High end SLR style digital cameras have much higher resolutions but they have both more expensive CCD's and higher quality optics to support that increased resolution. The higher quality optics are needed because ever smaller imperfections in the lens will lead to noticeable distortions in the image captured as pixel density increases. With the exception of some very impressive additional hardware and software the Lytro camera is essentially an eleven megapixel camera but it can't cheat as many low price digital cameras do by using optics that are not as good enough to support the reported pixel densities.

The Lytro camera has a rather odd aspect ratio of 1:1. In other words it takes square pictures. The native format of Lytro images is proprietary but you can export a jpeg image. When you do this you get a 1080x1080 picture which is a bit less that 1.2 megapixels. This is an interesting number when you take into account the fact that the camera captures 11 megarays of light. What this implies is that it currently takes around nine light rays for each pixel in the 2D image you can export from the Lytro software. (11 megarays/1.2 megapixel final picture = 9.2 rays per pixel). I'm not an expert in CCD's but a bit of research indicates that the high end of commercially available CCD's is in the 36 megapixel range. That would translate into about 3.9 megapixel 2d images if such a part were substituted for the CCD currently in the Lytro camera. As noted above though you would probably need better optics as well and there would be other implications such as much larger file sizes which would necessitate more storage and faster processing. All of which could greatly increase the cost of the camera.

Cost is currently one of the things people note as a limiting factor in the Lytro cameras appeal. Because of that ~ 9.2 to one ratio of rays to pixels in the final image you need higher quality components throughout the camera to get a particular level of quality. To be fair though this isn't a traditional camera and the comparison I'm making here is essentially comparing the Lytro's biggest weakness with one of the traditional digital camera's greatest strengths. Still, cost is likely going to be a constant challenge for Lytro in regards to their products both because they are a small company and because their technology appears to require higher quality components. This would be particularly true for high end products that had pixel densities sufficient to satisfy professionals.

I can think of at least one way to lower costs on future models though. It should be possible to use multiple lower price/resolution CCD's to capture higher light ray counts. If you look at the image below of the internals of a Lytro camera I believe the CCD is just behind the small light blue rectangle about 2/3rds of the way to the right.

If I'm understanding things correctly the light field sensor is taking the incoming light and breaking it up into a series of regions that are projected onto the CCD and in turn saved. Later on software is used to generate an image from these stored light rays.

You could in theory combine several CCD's into one mega CCD. This wouldn't work in traditional digital cameras as there would be gaps in the image where the various CCD's joined. This wouldn't have to be a problem for the Lytro since the sensor could in theory be tuned to accommodate such an arrangement by directing light rays only onto CCD surfaces and ignoring the borders.

Another advantage of such an approach would be the fact that you would have N paths to storage where N is the number of CCD's. Depending on the architecture this could mean lower costs as the communications bus between the image capture engine and storage could run at a lower clock rate if it were able to write to memory in parallel.

I'm getting a bit esoteric and am out of my depth here but suffice it to say that Lytro has some challenges in the area of creating higher quality traditional images. Future improvements in their software may yield a better than 9.2 to one ratio of rays to pixels. That would essentially be a free upgrade for those of us who bought the first generation product.

Significant improvements are probably going to require new hardware though. This isn't to say that the current camera is bad, it's not. It is very useful as is and based on conversations with Lytro employees there is a firm belief that a lot can be done to extend the functionality of the current model. I've spent most of my time talking about hardware in this entry and while the hardware is set in stone the software is not. When you take a picture with a Lytro camera you are capturing information about the scene beyond what is currently being processed and displayed. Support for three dimensional images is one enhancement that has been mentioned several times and there will likely be others.

I'll close here with one last observation. The Lytro camera is very durable. I accidentally dropped mine last night onto a hard wood floor from several feet up. Other than a very small amount of distortion in the case on one corner of the lens end it is fine.

Image via Wikipedia
Enhanced by Zemanta

Saturday, March 3, 2012

Lytro Camera, First Day

An extremely shallow depth of field, a common ...

There are a lot of things I love about this camera. There are also some things that I'm not very happy with. This isn't surprising given the fact that it is a first generation product with first generation firmware. Some of the limitations will hopefully be taken care of in future software upgrades but others will have to wait for next generation hardware. I'm fine with that. I've been on the bleeding edge of technology before so none of this is a surprise to me. I bought this camera knowing it was essentially a technology preview.

I'm going to insert a disclaimer here. I’m not a photographer, amateur or otherwise. I have only the vaguest notion of what an F Stop is and please don’t quiz me on any of the terminology because odds are I’m going to fail badly on any such test. Keep that in mind when reading anything I write that gets into the realm of photography.

As it stand now the Lytro camera is a fantastic but very limited tool. It is NOT a general purpose camera. The cost is too high and the features are very limited. Want to take pictures at night or in low light situations? It’s going to be difficult to get good results. You’re most likely going to have a lot of graininess and poor color. There are other problems as well, all of which have been discussed fairly thoroughly elsewhere so I won't go into them here.

One thing I really like is the macro capabilities of the camera, particularly when you go into creative mode where you can pick your focus point. Of course you can change the focus as much as you want later but it is still nice to be able to compose and see your shot right away.

What really excites me though is the promise of the future. All of the software feels more than a little unfinished but Lytro appears to have big plans. Support of rendering three dimensional images and infinite depth of field for instance. Lytro has some heavy hitters backing them so there is a pretty good chance they'll be given the opportunity to polish their first offering and continue to deliver additional products in the future. I certainly hope so. I'd be very surprised if Lytro is cash flow positive at this point but I think they can be some day. Whether they do it solo or partner with one of the big players will be interesting to see. The much less desirable outcome would be an eventual liquidation with somebody else picking up the IP later.

Image via Wikipedia

Enhanced by Zemanta

Friday, March 2, 2012

Lytro Light Field Camera, First Impressions

These are my very first impressions based on about fifteen minutes with my new Lytro light field camera. I have thirty minutes to type them before I have to get back to work.

I knew the camera was supposed to show up today so on a whim I decided to go home for lunch. It's a five minute commute for me so it wasn't a big deal. When I arrived home a brown UPS truck was just down the street. When I looked on the porch, sure enough there it was.

To the left is the box. I love the warning label. Ideally I would have rotated this image before importing.

 Here is the box opened. The packaging seems reasonable. I do run into a slight issue later that I'll describe below.
 And there it is, another very cool tech toy to explore and play around with. The size of the shipping box seems a bit excessive but that is kind of nit picky.
 And now we begin a series of pictures that show ever side of the box. I'm nothing if not thorough.

I have a confession, the picture to the left is faked in the sense that the camera had already been out of its slot in the shipping box. In fact, it fell out when I removed the top of the box. Luckily it fell onto a nice soft chair and bounced onto a carpeted floor so no damage was done.

I don't believe I did anything wrong when I opened the box. The slot in the lower part of the box is just very shallow. I suspect I'm not the first nor will I be the last person that drops the camera when opening the box. I recommend being cautious opening the box if you ever have the opportunity.
 Technically I should have let it fully charge first but I couldn't resist turning it on. I took my First picture with the Lytro right after this.
 In addition to the camera there is a small amount of documentation, a strap, a mini USB cable and a square thing about the same shape and size as the camera at its smallest dimension.
 The software is on the camera, just plug it in and follow the instructions. You'll need a Mac at this point if you want to use your Camera. Windows support should be coming later this year.

Oddly the Lytro software couldn't see the camera when I ran it at first. I unplugged it and plugged it back in and all was well.

I had three pictures on the camera when I plugged it in. The import process was painless but slow. Given the size of the raw image files and the newness of the technology this wasn't a surprise. You do have the option of starring certain pictures on the camera which gives them priority on import.

If you want to share pictures you have to create an account. You have the choice of linking to your Facebook account if you want. I went that route since it was quick. After that I was able to easily share the picture I linked above.

That's it for now, time to get back to work. I have some more thoughts I want to share later after I've had more time to work with the camera.
Enhanced by Zemanta