Tech

Canon T2i/550D Practical Video Review

4volt — Fri, 26 Feb 2010 10:58:56 GMT

I got my hands on the Canon T2i and I ran it though it’s paces, the things I was most interested in was the video modes and low-light performance.

To see the HD version downsized to 720p, you have to load the video from vimeo directly: Canon T2i, 550D Practical Video Tests.

T2i Vs. 7D

First a quick word about the T2i vs. the 7D. The T2i does not have that pro-feel that the higher level cameras have. The body is fairly light and it is most defiantly made of plastic, and you can tell when you hold it. For me that is not a big deal, it’s not worth nearly double the price to step up, though I do see the appeal.

Compared to “real” video cameras

In general I’ve been very impressed with the video shooting mode, in practice shots are easy to setup and the manual control works great. This camera lacks some features that a pro video camera may have, like a smooth auto focus, XLR audio inputs, and a power zoom.

Paired with a decent lens I feel that the video quality is just as good as the Canon XH-A1, a $3,000 HDV camera that I used in my last video shoot. In fact I would wager that the T2i is better in low-light, but I have no direct comparisons to show.

About the video codec

Video is captured in h264, at a high bit rate that is variable between 40 to 60 mb/s in 1080/30p and 1080/24p. I was unable to see any noticeable compression marks.

Needless to say, the video files are huge, order extra SD cards. A 4gb card is good for about 8 minutes of footage. Even though I knew that the files are big, I was surprised when the “No Space on Card” error came up, and it did twice while I was testing.

RAW still photos are about 20mb each.

I do wish that the camera settings like shutter speed, aperture and other EXIF properties were saved into the video, or at least the settings when video recording started. This is a minor issue barely worth mentioning.

Live View

A important feature for me is the ability to preview footage as it’s being shot, Live View mode in the EOS Utility works well, and a laptop would make a decent field monitor. The downside is that when recording the live view slows down to about 10-15fps, and motion is not a good representation of what is being recorded.

Another possibility is a HDMI field monitor, though I suspect a decent one would cost more then a average laptop.

When using live view and recording footage, the video file is written to the SD, not to your computers disk.

Capturing Video

Capturing video on the camera is easy and the manual controls are more familiar to me with my photography background then the manual controls on a pro-video camera.

Things that I wish it has was a live audio monitor and histogram, but those are minor things.

Auto-focusing is something that you will want to avoid when taking video, each time I tried this the lens over focused before it found it’s place. USM lenses are better, but I will probably still manually focus in most cases.

There is also a handy magnification button you can press for detail focusing that switches your live view on the lcd to 5x and 10x magnification.

Edit: You can start movie shooting with a remote, but you have to use the 2-sec delay setting on the remote, "immediate" mode on the remote takes a photo.

Another feature I missed is the power zoom for those very slow zooms, doing a slow zoom by hand is fairly difficult.

Audio

I have not yet had the chance to do detailed tests on audio quality, but my old Rode VideoMic works very well with it.

When the rest of my gear arrives, I may do another review of just audio qualities.

Editing Video

My computer is relatively good, a dual core 3.2 with 4gb of memory, a 4-disk raid 10 array and a GeForce 6200, and I've never had issues with editing 720p mpeg2 video. But my computer just doesn't have the power to keep up with the 50mbit 1080p stream. The video is fairly watchable in VLC, but in Premiere Pro 4.0 playback is very slow, perhaps about 3-5 fps. Editing this demo video was very tedious.

I’ll be looking to options for a new video card, and see what plugins are available that may be able to help.

Demo Video

See the video at: http://vimeo.com/9753969 (Or above)

I’m also publishing some of my test videos in a little collection. Most shots were done with the Canon 50mm f1.8 (non-usm) lens. The extreme close up shots were done with the same lens with a screw-on macro adapter.

Their is also one shot with the Sigma 70-300mm f4-5.6 lens.

It was important to me to do tests without any expensive specialty lenses. I believe both of these lenses are valued under the $100 USD mark.

All of these shots were setup in 5 minutes or less, on special rigs or setup was needed.

Room lighting is 4x65w flood bulbs, recessed.

No lights were used in the lit candle shots.

A 14w CFL desk lamp was used in the candle smoke shots.

Shutter speed was 1/30sec for all shots.

Conclusions

This is a great camera for a great price, it’s not perfect, but there’s also no un-resolvable issues.

Digital Video: The HD tipping point is now

4volt — Mon, 22 Feb 2010 22:29:17 GMT

Over the last few years HD video has been getting constantly cheaper, easier and better. I bought a used HD camera in 2001 (JVC HDGR1) for about $2,000 that was one of the first cameras under $10,000 that could do HD, and that it does at 720P, with some other deficiencies.

For a while now cheap HD has been available, for instance last year I bought a $150 camera that could also do 720P, but the sensor was small and noisy, that and the audio quality made the footage unusable.

However now the latest versions of digital SLR cameras as starting to be released with un-crippled features, things that independent film makers have been desperate for. Thinks like:

Full 1080P at 30fps and 24fps at a decent bitrate
Interchangeable lenses
Large sensors that allow for a shallow depth of field
Full manual control
Great low-light sensitivity
Audio input

Recently Canon announced the t2i, the first sub-$1000 camera that has all of those things. I think this is the magical price point that almost any serious hobbyist can afford.

How will this affect the digital video market, and the indie film market?

I think the effect will be very similar to the digital (still) camera explosion that has been continuing. More people will have access to high quality recording, but that does not necessarily mean they will be any good at it.

For the people that are skilled, or willing to learn the skills to take good video, there’s a whole new world of possibilities opening up.

I know I’ll be ordering one of the t2i’s as after it’s released, if you want to help, send in a donation. I would greatly appreciate it.

Power required to emulate a human brain

4volt — Sat, 06 Feb 2010 07:27:47 GMT

Recently, I posted a article about how much computational power it would take to emulate the human brain, and my calculations were off by a factor of 10. I've corrected my estimates and here are the updated sections:

Emulating the Human Brain

The Blue Brain Project has successfully simulated 1 cordical column on the Magerit super computer (100 TeraFLOPS), and human brain has an estimated 1,000,000 columns.

So with 5.2 ExaFlops, one could emulate 52,000 cordial columns. And that’s 1/20th of enough power to emulate a human brain.

To emulate the entire human brain you would need approximately 100 ExaFLOPs

That's a lot of FLOPS!

I chose the above estimation because many others rely on calculating how many operations per second the brain can processes, not how many computer calculations to emulate the brain. I.E. It takes many more computer computations to emulate a brain computation.

Fore some more notes see: http://www.smartcomputing.com/articles/2002/s1302/39s02/39s02.pdf

Conclusion

Henry Markham in his recent TED talk, thinks that a human brain could be emulated in 10 years.

I agree with his estimate, using Moore's law 10 years seems like an achievable goal.

If you are interested in the subject you may also like Ray Kurzweil's research and books.

Total Processing Power of the Internet

4volt — Mon, 18 Jan 2010 23:38:03 GMT

As a brain exercise I decided to try and estimate the total processing power of all the computers on the entire internet, and see if that is enough processing power to emulate the human brain.

Since this is an estimate, I will try my best to figure it out with public data.

Here was my process:

Total Number of Computers

No one knows exactly how many people (computers) are connected to the internet since a single IP address can be shared with any number of pc’s, but the best estimate I was able to find was here: Internet World Stats

They use population statistics and penetration data to estimate this. This does not include extraneous connected devices like gaming consoles, or other devices.

Total Computers: 1,733,993,741 (1.7 Billion)

Effective Processing Power per Node

Since all the computers are separated by the internet, I chose to use SETI@home as a benchmark for the effective benchmark of how much processing on average a node can handle

According to BOINC stats, Seti has 186,250 active computers (more inactive ones), and the peak processing speed is 704.507 TeraFLOPS (tF). (As of 01/17/2010)

That’s 3.782 GigaFLOPS (gF) per node.

Also, on average computers running SETI are probably faster then the average computer online, especially considering poorer countries. So lets round down the average to 3gF.

3 GigaFLOPS is much lower then the peak processing power of a modern computer, a (Intel Core i7 965 XE), can process about 70, while some of the newest GPU cards can process upwards of 1,000 GigaFLOPS.

This leaves me to believe that tele-processing is very inefficient compared to traditional supercomputers, though it is not without advantage.

Total Processing Power

Now, assume all 1.7B computers were all running this hypothetical peer to peer processing application, and bandwidth was not a bottle neck.

1,733,993,741 * 3 = (5,201,981.223 TeraFLOPS, or 5.2 ExaFLOPS)

In case your wondering:

1 Peta = 1,000 Tera

1 Exa = 1,000 Peta

Currently the fastest supercomputer is “Jaguar” with 2,331 TeraFLOPS. (Top 500 November 2009)

Emulating the Human Brain

The Blue Brain Project has successfully simulated 1 cordical column on the Magerit super computer (100 TeraFLOPS), and human brain has an estimated 1,000,000 columns.

So with 5.2 ExaFlops, one could emulate 52,000 cordial columns. And that’s 1/20th of enough to emulate a human brain.

To emulate the entire human brain you would need approximately 100 ExaFLOPs

That's a lot of FLOPS!

Fore some more notes see: http://www.smartcomputing.com/articles/2002/s1302/39s02/39s02.pdf

Wrap-up

After reading more about the Blue Brain Project, they are emulating a cordial column, as well as analyzing and visualizing that data, which is not necessary for a independent AI.That coupled with the inefficiencies in communication with tele-processing, I suspect that there is a lot of improvement that can be made.

Henry Markham in his recent TED talk, thinks that a human brain could be emulated in 10 years.

I agree with his estimate, using moore's law 10 years seems like an achievable goal.

If you are interested in the subject you may also like Ray Kurzweil's research and books.

Alternatives

More likely a successful AI would be a efficient Emergent-type hive AI. Where independent nodes contribute to a beneficial goal with independent actions. This would not look like a traditional AI to us, the patterns would probably to numerous and vague to track accurately.

This was meant as a thought experiment, if you have any comments please leave them. I will revise this article as I see fit.

CES Post-mortem picture extravaganza

4volt — Wed, 13 Jan 2010 21:19:02 GMT

This past week I was at CES doing market research, and I'm sure everyone reading any of the tech/gadget blogs have had a overload of CES related coverage. I’m not going to talk about any of the things that got major coverage, but here’s some general thoughts, and a couple things you probably didn’t see anywhere else.

3D TV is coming at you like a 900lb gorilla
Pretty much every TV/Monitor manufacturer has a 3D version of a product coming out, and with Blue-ray updating it’s standards to support 3D, I suspect we’ll see some TV’s and monitoring hitting the market very soon. In fact be prepared for a deluge of 3D stuff and marketing this year.
Lego Universe
Lego’s new game “Lego Universe” looks pretty cool, there stand also had big bins of lego minifig parts to build your own lego men. Pretty cool, but mostly I wanted to post pictures of the epic lego battle we had while waiting.
District 9 Props
Sony had some props from the District 9 movie, which I enjoyed toughly. It was cool to see some of the props up close.
Tekzilla Filming
We caught the Tekzilla filming at the NBC stand, and we’ll probably be seen somewhere in the background, I'll post up a link when the show is posted. http://revision3.com/tekzilla
Babes
It’s not CES without booth babes right? Here’s a few.
Star Trek
With the recent popularity of the new Star Trek movie, there was a few models and props, including a very strange Enterprise/Turntable mashup.

That is all.

US Droid + Root = Multitouch?

4volt — Mon, 16 Nov 2009 19:05:47 GMT

After having the new Motorola Droid for about a week, I've been very impressed with it’s features, usability, and experience.

Previously I was using a windows mobile phone, and as far as usability goes, Android is leaps and bounds better then even the latest (6.5) version of Windows Mobile.

Although, when I show my phone to an iPhone users, they generally complain about the lack of multitouch, especially in the web browser, and the on-screen keyboard. I think that feature alone will end up being a major sticking point when people talk about switching from the iPhone to the Droid.

As you may or may not know, the US version of the droid does not have multitouch in the apps that Google/Verizon distributes with the phone (including the browser and keyboard). The speculated reason why multitouch is not enabled in the US Droid is that apple’s patent on multi-touch that is not valid in Europe.

After some little research there is a app (PicSay) in the Google Marketplace that takes advantage of multitouch on a stock, unmodified US Droid for zooming pictures. So, it is true that multi-touch is supported and enabled in hardware, but not taken advantage in software.

My theory: multitouch is only disabled by configuration in the Android OS, and if one were able to root the US Droid they could re-enable multitouch with some simple configuration changes.

This assumes that Google uses the same distribution of apps for both US and Europe. Although, if that is not the case, one could alternatively copy the European ROM (or apps) to the US phone with a minimum of fuss.

I'm keeping my two fingers crossed for a root exploit in the near future, and the possibility of multitouch. At this point I think it’s probably too late in the game for Google/Verizon to change their minds about multitouch, though I hope they do. It would make the Droid a stronger competitor with the iPhone.

Also, Android Marketplace developers should be, or may already be working on a multitouch version of the on screen keyboard. An independent app could take advantage of multitouch, and wouldn’t require rooting the phone, so you could type with two fingers.

Update 12-08-2009:
Dolphin (A 3rd party web browser) that you can get in the marketplace supports multi-touch. Search for it in the marketplace, it's free.

Update 12-10-2009:
A root exploit for android 2.0 on the droid was found and after reading into it, it looks like the apps in question were complied without the multi-touch libraries. It should be a matter of re-compiling or coping multi-touch binaries.

Since dolphin exits, I think if someone were to make a multi-touch on-screen keyboard, people would not have much to complain about .

Update 01-29-2010:
This article is now out of date, but most people are just just downloading multi-touch apps and calling it good, though there are also some mutli-touch + root modifications you can do to the droid and nexus.

Photos: Running a exposed hard drive, and then ruining it

4volt — Mon, 06 Jul 2009 05:31:11 GMT

Way back in 2002, I ran an experiment with a hard drive to see how durable the inside actually is, mostly curious to see how easy it is to ruin a drive.

In the 2nd above photo you can see the drive arm moving, all of these photos were taken while the drive was being used in a live system.

We removed the cover of a old IDE hard drive and proceeded to format and install windows. We didn’t make any attempt to protect the drive, and the office we worked in at the time was pretty dusty. The format and install did work with some errors, and eventually we got the computer to boot in safe mode. The computer worked but just barely, it was plain to see it wouldn’t last for long.

After that crude test, we decided to take it to the next level and pour water into the running drive, mostly just to see what would happen. We covered the live pc with plastic, and took some other electrical safety precautions.

We started with just a few drops on far side of the arm, the water more or less sprayed right off of the moving platter. Later I made a quick calculation and found that the edge of the platter at 5400rpm moves at an estimated 56 miles per hour (90kph).

After the water the drive arm moved wildly, and eventually went back to the edge. A few quick tests showed the hard drive had more or less failed at that point, but continued to spin and try to seek. Since most of the drive electronics are on the circuit board underneath, that’s not too surprising. Although if a drive fails catastrophically, usually they stop the spin. I’m sure it would be possible to retrieve the data if the drive heads were not damaged.

After the light dousing, we decided to pour the whole glass on the drive, and like before it more or less just splashed off the drive, but was exponentially cooler.

In the end it was just for fun, and it produced some interesting photos.

Using the Minimal Arduino

4volt — Wed, 27 May 2009 15:47:48 GMT

Todbot has posted an excellent tutorial on how to setup and use the minimal Arduino, which is the bare minimum you need to run a ATmega chip and the Arduino bootloader.

Todd goes into detail about how to get the bootloader onto the chip as well as how to setup the Arduino environment to use it.

Even if your not interested in building an Arduino from scratch, It’s a good read if you are interested in the technical aspects of what makes the Arduino work.

http://todbot.com/blog/2009/05/26/minimal-arduino-with-atmega8/

Stripping a Scanner for Parts (in 10 minutes)

4volt — Thu, 21 May 2009 04:35:12 GMT

I’m starting on a project that I’ll be using stepping motors and belts, and after looking for cheap parts online, I thought I could do better by stripping down some old scanners.

People are excited to get rid of there old computer stuff, the great thing is it doesn't matter if the old scanner works. Even if it doesn't turn on likely the motor and mechanical parts are still good for salvage. I posted a ad on Portland’s craigslist in the wanted section and got several responses, in a week I had a bunch of scanners for free, I only had to pick them up. I found that putting in the ad that you would be reusing the parts for a robotics project people were very interested.

Scanners are easy to take apart, they are pretty simple machines and generally there are some catches, and a screw or two around the edges of the top cover.

Once the cover is off, you can start stripping parts, the valuable and easy to use parts are the stepper motor, linear slide, belt and gears. There may also be an optical end-stop sensor, and some buttons that are easy to re-use. You can get more hardcore and try to salvage parts on the actual circuit board, but that takes a bit of research to figure out what is useful.

Here are the parts from two example scanners, both have similar parts and took about 10 minutes to gut.

From all my scanners I salvaged at least:

1 Stepper Motor
1 Linear slide bar
1 Timing belt
1 Set of gears for the belt
A few buttons and LED’s

If I were to buy those parts I would be spending at least $20-30, and they are all in good usable condition, just for the stepper motors alone it was worth my time. Also most of not all of those scanners would have went to the landfill. I was able to recycle most of the electronics, and I put the plastic shells in the city recycle bin, that’s something you can’t do while the electronics are still inside. That’s a net win anyway you look at it.

Update: While it's outside the scope of this article (10 minutes or less) to get into the details of salvaging more electronics, read the comments below for some more interesting comments and uses or other parts found in scanners.

Theo Jansen on "Robots Podcast"

4volt — Mon, 27 Apr 2009 07:09:15 GMT

It’s no secret that I’m a fan of Theo Jansen’s work, he is the inventor of the Jansen Mechanism that I used as the basis of my recent Jansen Walker project.

Jansen was recently interviewed on the generically named "Robots Podcast" where he spoke about his thoughts on if he was a artist or scientist, if the Strandbeest have thoughts, his building materials, the design of the legs, how he would like the Strandbeest to outlive him, also microcontrollers and commercialism.

Check out the podcast over at Robots Podcast.