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Archive for July, 2009 - Page 2
Posted by Jack Crossfire | Jul 08, 2009 @ 02:51 AM | 5,038 Views
This lens is so powerful, it can see back into the 80's.

Let's get 1 thing clear. It's a piece of junk compared to Canon lenses. It's blurry at 800mm & extremely blurry at 1600mm. At 18oz fully loaded, it's too heavy for the trapezoid mount.

The answer is no. The 2x teleconverter doesn't buy any more resolution. The fact that the 2x teleconverter has no front lens cap shows how valuable its manufacturer thinks it is.

What the 2x teleconverter buys U is sharper focusing. If your goal is focusing bright objects, use the 2x teleconverter & throw away 1/2 the frame to get better focus. It's much easier to focus this way.

It's probably no better than a 400mm L & it's probably no better than a 200mm L + 2x teleconverter for $200 in 2007. Unfortunately the Canon 2x teleconverter jumped 50% since then. It's definitely better than a 200mm L as shown by this award winning blog post.


F/8 is a really narrow depth of field. F/8 & F/16 R not a problem when using a tripod & a modern digital camera. The Canon's focusing squares R useless. It's too blurry & dark. Unfortunately, F/16 brings out all your sensor dirt.

U need to fabricate a lens platform to mount it on a tripod. It's too heavy to hang off the camera body.

Focus guides on T mount lenses R worthless because they always go on the bottom, but it still has a focus guide....Continue Reading
Posted by Jack Crossfire | Jul 07, 2009 @ 01:36 AM | 5,197 Views
debbie gibson someday (4 min 4 sec)

Here it is. A monster of a video from the lost corners of the 80's. Mashed a pristine audio track with the 2 crummy Goo Tube videos to get the best quality possible.

After throwing together a layout for the 915Mhz radios, it became quite clear that any standalone data radio would probably be too heavy for a Picco Z size spin copter. It would need to do the processing + radio on 1 chip. Would also have to use the Maxbotix transducer instead of the Matsushita to minimize weight.

Vika 1 will be 915Mhz & get a new ground station specifically for 915Mhz & sonar. 915Mhz will use SPI & no RS232. Vika 2 will stay 2.4Ghz. Moving the radio to SPI is a pretty big change. We start with the ground station. Just need a USB cable.
Posted by Jack Crossfire | Jul 06, 2009 @ 04:36 AM | 5,009 Views
VikaCopter uses a PID gain for autopilot & a PWM gain for all modes. If U max out the PID gain, U have to increase the PWM gain. PWM gain was low to make it easier for a human pilot, but the human had to go. Here we have the 4 camera angle & nose in orbit with effective rudder & stabilization.

rudder effectiveness regained (7 min 8 sec)

The answer is no. The Castle BEC has no reverse current protection, so we finally fried it. It has a fuse diode which doesn't seem to have been enough. Lineage power makes buck converters which make all BEC's obsolete.

Now 4 your 80's minute.

Low quality audio without dropout, higher quality video.
Deborah Gibson Someday (3 min 52 sec)
...Continue Reading
Posted by Jack Crossfire | Jul 05, 2009 @ 02:52 AM | 4,977 Views
U may have tried to erase it from your memory, but we did dream about a flying flag many years ago. Flew VikaCopter higher & higher with a flag attached until eventually it didn't come down & it reached orbit. Months passed and the orbiting flag became a routine fixture at night, filling more space than the moon. Over time it became more tattered & faded from view because of micrometeorites & entitlement programs....Continue Reading
Posted by Jack Crossfire | Jul 04, 2009 @ 11:33 AM | 5,237 Views
Underslung payloads 4 U (4 min 15 sec)

There it is. All flights have to take off pointing North & turn into the wind because of the 3DOF IMU. Managed to pull off some stiff wind without blowing string into the propellers....Continue Reading
Posted by Jack Crossfire | Jul 02, 2009 @ 01:40 AM | 4,994 Views
Obviously, if U want smooth orbits U need a dedicated orbit command & not 4 waypoints joined by curves. Probably the only way to do it is to have the computer look 1 waypoint ahead. Unfortunately, U can't read 1 waypoint ahead in a C program.

Pretty major software change, & reason to give U the long orbit footage with the current software to keep the blog alive.

pico C programs & wind (7 min 5 sec)

Some hovers demonstrating the latest SCP1000 tuning. Then some pico C programs: a nose-in orbit, nose-out orbit, & some laps. 3DOF IMU, GPS, & SCP1000 of course.

None of these programs move very fast in any wind. Changing heading while moving is real hard. The idea of a curved path & heading changes is pretty hopeless in any wind.

Now some stills 4 those of U who don't have day jobs to spend watching Goo Tube.
Posted by Jack Crossfire | Jul 01, 2009 @ 03:06 AM | 5,182 Views
Tri rotor's first daylight footage (4 min 26 sec)

Pretty tough wind but really clear air. The last time we flew a camera here was this award winning blog post almost 1 year ago.


Had yet to achieve the wealth & power required to etch tiny boards & the software was still 100% embedded.

Today, still don't have enough tail rotor authority to turn against the wind. Spent most of that footage banked over 30deg to stay in place. The 4 turn mission was more like a 2 turn mission. At least she's much more stable than the T-Rex.

TAIL ROTOR FAILURE (0 min 34 sec)
...Continue Reading