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Archive for July, 2017
Posted by Jack Crossfire | Jul 29, 2017 @ 07:51 PM | 3,232 Views
with forced air requires powering it externally.

It was crazy hard to make this camera take power from the pocketjuice. The cable had to be under 6ft or it would shut down. Only speaker cable had low enough impedance. The fan cable is still a 4 conductor phone cord with 2 unused conductors from earlier in the day. The cooling system seemed only marginally effective. It hit 36C with forced air & the low 40's without forced air. It hit 56C in a hotter part of the day without forced air, but wasn't directly measured with forced air.

It might work better with the fan blowing perpendicular to the battery compartment instead of angled. This gives air an escape path. The cooling system was rebuilt twice to make it not appear in the frames.



It was fortunate to spend the extra money on an 8Ah battery with 3.4A rating over USB. When derated to reality, it's probably barely enough to feed the camera's 1A & fan's .2A.





The next outdoor test had better focus only in the exact center, but still was horrendous near the edges. It might require removing material. Another possibility is buying another camera for a lot less money & interchanging parts or just getting version 2 & not bothering with 30 megapixels. Because neither camera is anywhere near ideal, it's a lot of fuss over nothing. The quality is just barely acceptable for 1920x1080.


Forced air cooling worked. The cooling system didn't get in the shot or cause camera shake. The 2 frames could be...Continue Reading
Posted by Jack Crossfire | Jul 28, 2017 @ 11:30 AM | 2,618 Views
It took a whole commute just to install the board & fix the firmware enough to make it work. It's a very high density board built around the size of the ATMega. There wasn't enough room for a button, so the only way to set the timing is soldering on a 5 pin programming header & flashing it. There are pads for a serial port, so it could be configured by a VT100 interface. It's started by shorting a jumper. Losing the jumper would be fatal.


Of course, any bluetooth module would be the same size & have a wireless interface, but there wasn't enough time to build up the software.


This revealed the Samsung takes .5A when idle & spikes over 1A when shooting a still photo. For video, the current was a constant .8A. When shooting photos at full speed indoors, the heat reached 55C or 131F.


It immediately became clear that the Samsung loses its settings without power. The mane setting is a timer which defaults to 2 seconds. Retaining the settings would require always having a battery in, so terminating the offboard battery connector.

The decision was made to shoot photos as fast as possible. The mane limitation is compression speed rather than SD card speed. UHS 1 or UHS 3 cards only got only 1 photo every 1-2 seconds. It buffers 3 frames while writing.


The debouncing on the shutter button is very forgiving compared to Goog's non deterministic, fuzzy debouncing algorithms. You can make the intervalometer fire as fast as possible while it's still...Continue Reading
Posted by Jack Crossfire | Jul 27, 2017 @ 02:50 PM | 2,878 Views
Cutting a $32 sheet of silver impregnated mylar is stressful. Be sure the CA glue has cured before applying the filter, or it'll fog up.
Posted by Jack Crossfire | Jul 26, 2017 @ 03:54 PM | 3,281 Views
https://www.aopa.org/news-and-media/...r-in-the-works

A $250,000 plane which costs $19/hour to fly & can reach useful distances, if you believe the pitch. You could buy 8 & fly to work for the same cost as living near a job. Whether or not this incarnation ever materializes, battery prices may be low enough to cause serious disruptions in population distribution. To be sure, much of today's decisions are cultural rather than economic. The current generation is obsessed with experiences over money, devoting all its output just to live in the middle of a city.


Despite that cultural boundary, cheap batteries have already slightly impacted populations in cities, in the form of electric skateboards allowing commuters to go 5 miles farther. For many years, this market studdered between segways, hoverboards, unicycles, & scooters, but this year seems to be converging on the electric skateboard. While millenials will never choose money over location, they are being allowed a choice.


If few enough people chose to leave cities & fly to work, it could be a massive boom to those who did. If enough people left cities to depress housing prices, the government would most certainly impose drastic measures to stimulate housing prices. It definitely wouldn't be a choice if enough people did it. There would probably be negative interest rates & huge asset inflation until a house in Montana suddenly cost $80 million.
Posted by Jack Crossfire | Jul 26, 2017 @ 02:45 AM | 3,660 Views
The 1st test of the Gear 360 on the pole was a failure. The Samsung recorded a 4k timelapse for only 15 minutes, overheated & stopped, but didn't power down. The Gopro recorded 4k 30fps for the full 28 minutes. Mechanically, the setup worked quite well. Would definitely brace with the big tripod while setting up the tent posts. It wobbled in the wind. It couldn't be extended completely. The wobble was quite obvious in the gopro footage, but the Samsung stabilized all of it out. Sadly, the Samsung's rear camera was out of focus.


The improvement from elevating the camera 11 ft was only obvious nearby, while the horizon was virtually unchanged. It might get over people's heads. Combined with the wobble, a quad copter would have been a better solution.


Important to note the Samsung only records timelapse in 3840x1920. Only single photo mode takes 7776x3888, in which case the broken rear camera was horribly out of focus & the edges of the FOV on both cameras were worthless. Photo mode does extract more detail from the center of the cameras. Making a timelapse would require cracking it open & wiring a remote control to it.


The most reliable way to start recording was decidedly pressing the buttons with the pole retracted & then extending it. Use a mirror to view the Samsung's display. Any wireless method is more risky.


The Samsung's long rehabilitation began with repairing the focus. It required digging all the way down to the...Continue Reading
Posted by Jack Crossfire | Jul 26, 2017 @ 12:33 AM | 2,672 Views
It's the 1st graphics card a lion paid for in 19 years. The last one was a $50 AGP with no 3D, which could barely play low definition video. For 17 years, lions got by with leftover day job parts & donations. After 10 years, a version of Linux which could decode H.265 no longer supported the Quadro FX 3400. It probably would be cheaper to use Windows & have Linux in a virtual machine, nowadays.


This one was $135 & way overkill for the ancient CPU. It uses far less power than the 3400 & doesn't need the extra power connectors lions long lived with. It was all about getting the most driver longevity. The 1050 came out in 2016, so the drivers should last until 2025. Suspect PCI Express won't be around by then. The current CPU is 7 years old, so an upgrade could be within 3 years. There's marginal improvement in 4k video.
Posted by Jack Crossfire | Jul 22, 2017 @ 01:24 AM | 3,328 Views
Then it arrived. It was a brick compared to the gopro. Something would have to be done to protect the lenses on a vehicle. It didn't output JPEG photos. Its timelapse movies were all H265 files. Its MTP implementation barely worked. It didn't work with any phones in the apartment. Fortunately, all the required modes except remote control were accessible from the hardware.


The lack of video editing software was disappointing. It'll take reinstalling Linux merely to compile an H265 decoder, which is about as bad as reinstalling Windows. The decision was made to have the Samsung make timelapse photos on a tall pole, with the gopro making 4k video right below it. Starting them up remotely & cooling them is the tricky part.


Things didn't go so well in the narrow angle video department either. The t4i doesn't support Av or Tv in video mode, only fully automatic or fully manual. Fully automatic might actually be enough. Narrow angle video isn't the mane priority.
Posted by Jack Crossfire | Jul 18, 2017 @ 12:18 AM | 3,772 Views
The absolute best eclipse movie possible with today's technology would be a realtime 8k in hydrogen alpha. This resolution could reveal individual mountains of the moon overlapping prominences of the sun, without zooming in. The only videos the goo tube comes up with are extremely poor quality. Thus, the lion kingdom expects similarly poor quality of the 2017 eclipse.


Unfortunately, the idea of rigging the servocity to track the sun is not looking good. Testing with the trusty signal generator showed PWM to not be accurate enough. Direct driving the servos with H bridges doesn't look good either. They have to get above stall speed & wait for inertia to slow down. The minimum speed it can step is too fast. These problems didn't happen when using wide lenses, but are deal breakers with the 200mm.
Posted by Jack Crossfire | Jul 16, 2017 @ 03:44 PM | 2,921 Views
Based on the research, every section of totality near a road is going to be packed so there won't be any quad copter flying. There are very few roads & all the land owners have already rented out parking spaces for a lot of money. A bathroom is required for such a mission, but all the bathrooms are going to be near said parking spaces. It's burning man on a nationwide scale. It won't be possible to book a parking space at the last minute, based on weather. Polecams are looking like the best move, but there are going to be a lot of tall RV's. Would say the protocol is pay a huge sum just to park the vehicle & then hike somewhere.


Having said that, there are a lot of do or die events lions never saw besides totality. Lions never saw a space shuttle lift off or got married. The mane attractions are the chance of a shot no-one else is going to get & keeping up with the Joneses. The best chance of someone else getting the shot is given by the 360 craze, but this craze has run its course & there are now very few 360 cams around, let alone operators interested enough to bother mounting them on a pole.
Posted by Jack Crossfire | Jul 15, 2017 @ 06:14 PM | 3,035 Views
This blog post was rejected by diydrones because it was too exotic a use for a quad copter, but here it is anyway.


Most diydrones viewers are from places outside of it, but a small number of us do live in the U. Know. Where. & intend to view the total eclipse on Aug 21. The best viewing location is a mountain on the east side of a valley, in good weather, in a place you can actually reach. This should give a good view of the shadow moving across the ground. Unless you have a very good telescope with H-alpha filter, it's not worth trying to photograph it. There are going to be many photos of the eclipse, maybe some good timelapses of part of it if we're lucky, but absolutely no-one is going to document the earth under the eclipse.


The problem is satisfying all 3 requirements is very hard. All the accomodations in the path of totality are full. Anything with a campground in the path of totality is turning away everyone on that day. The good locations are inaccessible by road or on private property.


It's a perfect opportunity to make your own mountain. The journey began to get back into the quad copter game, but rather than build something from scratch, just buy a finished package. The days of buying hundreds of dollars of sensors & navigating 80MB of source code for something as germane as a quad copter are over.



The copter needs to fly as high as possible & lock a camera on the western horizon for 10 minutes. 20 minutes would be nice, but...Continue Reading
Posted by Jack Crossfire | Jul 13, 2017 @ 11:27 PM | 3,847 Views
Compared to what Bezos was offering for $400, B&H threw in an extra battery & viewfinder for $300. Either they must be having a hard time getting rid of the pros or Bezos is milking an extraordinarily inefficient market fueled by The Janet. People must prefer what the Chinese cams offer, despite the limitations.


This is still the action cam that Casey Neistat, Ginger Runner, Billy Yang & all the greats used during the peak of the goo tubes. After the Goog slashed profit sharing, the quality of the content dropped like a lead weight & the golden age ended too soon for the Hero 5 & the DJI gimbals.



Well, the free charger is only a battery charger in the academic sense. Similar to the Wasabe charger, you're better off using the camera.


The viewfinder is only a viewfinder in the academic sense. It's a touch screen. It stays on for a few seconds, but not long enough to frame a shot. Resolution & screen size aren't high enough to frame anything accurately or judge exposure. It bobs up & down like interlaced video. It's most useful for configuration.


It records 4k 24fps off a 2A USB power supply with no viewfinder. It requires a battery to record with the viewfinder. 4k 24fps goes down at 60 megabits.


The lion kingdom was immediately confronted by the mysterious 4k superview mode. The problem is the Ambarella only has enough clockcycles to encode 3840x2160 pixels, but the full sensor has a lot more pixels in a 4:3 chip. They...Continue Reading
Posted by Jack Crossfire | Jul 10, 2017 @ 11:20 PM | 15,720 Views
The Shot Well was interviewed on the space show here http://www.thespaceshow.com/show/22-...wynne-shotwell . Here, she revealed they're renaming the ITS back to the BFR, big f*cking rocket. There was 1 of the few references to her husband, so the internet needs to stop writing Ms. They've fired the scaled raptor engine over 25 times, but have not even decided what its full size should be. The full size is determined by the knee in cost/performance & is converging on 2.5x the scaled size of 200,000lbf. They're now considering another Falcon 9 revision with raptors. Still impressive that the scaled raptor is as powerful as the final merlin. They could just swap in the scaled ones.


Their mane focus is the falcon heavy demo flight, dragon 2, & falcon 9 block 5. Then there's faring recovery, stage 2 recovery. There's no material investment on the BFR, the lunar flight, or any of the other stuff on Musk's twitter feed. There wasn't anything on what happened to the carbon fiber tank besides they're still trying. The Falcon 9 block 5 has valves rated for many cycles & tanks rated for many more pressure cycles. They're doing "some work" on the octaweb. Blocks below 5 can only fly 3 times.


It seems if Musk put just the effort on boring & hyperloop on the BFR, it would be a headline maker, but Tesla still isn't making money & there aren't enough roads to drive the number of cars he needs to sell. People are going to put a lot more...Continue Reading
Posted by Jack Crossfire | Jul 09, 2017 @ 05:15 PM | 4,633 Views
After much studying, the decision was made to restart the party with a $300 gopro hero 4 black. There are an awful a lot of action cams & ambiguous chicken scratch to digest, but here are the facts a lion can discern:

All the sub $100 action cams by noname Chinese brands have truly awful, hazy, blurry picture quality. The pros are still far beyond in picture quality. Extracting stills was a big deal & it requires the best picture quality.

The Yi 4k is a brick, doesn't have 1920x1440, & wouldn't fit in the Feiyu. While it has effective image stabilization & high quality, it should be considered a full size camcorder.

The hero 4 session has an inferior picture to all the full size 'pros. The hero 5 session costs as much as a full size hero 4. The sessions don't fit in the Feiyu mini 3D.

The hero 4 black does 4k 30fps but has no viewfinder. The silver has the viewfinder but does 4k in 15fps. Lions have never ever regretted not having a rear viewfinder on an action cam, not even enough to bother using the wifi preview or wiring an offboard screen to it.

Gopro is still the only one offering 1920x1440, the solid gold format & the only format lions ever used. The 1920x1440 format was the only way to extract stills from video & stabilize without cropping.

The hero 4 was the last one which fit in the Feiyu.

The hero 5 achieves image stabilization by cropping & it's not effective.

The hero 5 is bigger & heavier than all the other 'pros, on account of waterproofing. All the corporations are building waterproofing into every gadget because water damage is a big cause of returns.

The full size 'pros are as light as the sessions if powered without a battery. There are many conflicting rumors about how to power a pro without a battery. The problem is the current generation no longer understands ohms law.

There was a very limited supply of hero 4's at $300. That price was a steal for a 'pro.
Posted by Jack Crossfire | Jul 09, 2017 @ 01:08 AM | 15,999 Views
The truck finally got a dual battery setup with polarized Dean connectors. This didn't require a fuse. The problem was having live, exposed contacts when only 1 battery was used. For the top connector, the solution was terminating it with another Dean connector with the terminals wrapped. The bottom connector doesn't have a cover.


To plug in the batteries, the top connector must be covered & the bottom battery must go in 1st. Then the top battery can go in. To remove the batteries, the top connector must be unplugged & covered before removing the bottom battery. If the bottom battery is unplugged 1st, its live contacts are right next to aluminum, causing a fire after the explosion.


This arrangement with water, speaker, shirt, & polecam used 7166mAh to go 12.5 miles. It was an extraordinarily bad 573mAh per mile. The last mile was hauling food. The newest battery once again discharged more than the oldest battery. Its maximum range would be only 16 miles. The water was drained throughout the 1st 7 miles.


Replacing the aluminum with plastic angle rod is a leading theory, but the lack of shock absorbers may be sapping energy.
Posted by Jack Crossfire | Jul 08, 2017 @ 11:17 PM | 16,906 Views
Polecam with 808 #18 keychain cam (2 min 24 sec)



So ordered the smallest, cheapest $30 camera available for the polecam. It turned out to be the 808 #18 keychain cam from 5 years ago but this wasn't labeled on the amazon & for someone who lived 40 years ago, it was hard to believe something that obsolete was still being sold. Progress has slowed immensely.


Techmoan already moaned about how horrible it was & how great the mobius cam was. Its 1st drive was with 2 batteries, so a direct comparison with the stability of the gopro wasn't possible. It was stable, but still wobbled. It fell over once because of a curb. Would actually say the increase in stability was negligible. The vehicle & pole are so much heavier than the camera, it's probably not worth using a keychain cam for any reason besides longer recording time.



It recorded for exactly 1 hour, but could record for many hours by soldering in an external battery. Now, the mobius cam is $70 & roughly the same size, but it was already clear that polecam would be the only form of videography from now on, whether it was crusty vlogs or cinematic shorts. There would be no reason to use a micro camera.
Posted by Jack Crossfire | Jul 07, 2017 @ 02:14 AM | 3,921 Views
So the lunchbox was loaded with 2 batteries, 20oz of water, a shirt, speaker, cheap camera, & phone. The headlights were off. It went 5.65 miles at 9min/mile, 5.85 miles at 8min/mile, & .3 miles hauling burritos. The 5.65 miles took 3111mAh or 531mAh/mile. The 6.15 miles took 3435mAh or 558mAh/mile. So if it drove at 9min/mile, it would probably only go 17 miles compared to the previous lunchbox going over 20 miles with the headlights on. Another 2 battery test without water bottle is needed.


The other tests without water bottle were with 1 battery, a shirt, speaker, phone & no headlights. Those were around 400mAh/mile. The range would be 22 miles. The aluminum should be replaced with plastic. The tires should be locked to the wheels.


Given the low current of these vehicles, 18650 cells may be a better power source.
Posted by Jack Crossfire | Jul 03, 2017 @ 01:28 AM | 3,535 Views
Polecam 3 (3 min 47 sec)



It lasted 4 years. While riding on polecam 3 after finishing recording, it flipped backward & crashed into the street. The pole amplified the impact speed like a baseball bat. Lowering the lunchbox didn't make it as stable as hoped. A heavy payload & polecam made it quite undriveable. The polecam alone made it less stable, but it still managed to drive 9 miles. The string still loosened after 5 miles & had to be retightened.


A gopro sized cam 40" above street level, with no enclosure, is the maximum for the lunchbox to be driveable. The height wasn't unbearable. In fact, this is a popular height for many productions & it's taller than all the single women of lion age, today. A keychain cam might go higher, but the need to duct tape 2 carbon fiber rods & add extra battery power might negate its weight.


The lion kingdom never paid for a camera for 7 years. The pace resumed last month, with the cheapest still photo camera available. After destroying a few in quad copters, 7 years ago, it was decided there was enough value & it was long enough since the last camera got destroyed to give them another go. Despite being 3 years obsolete, the picture quality got rave reviews compared to any modern phone cam.


There won't be a gopro replacement for a long time. The brushless gimbal may remane dormant. The gopro was dormant for most of its life, with only sporadic sessions attached to a brushless gimbal or a vehicle. Because the view from the polecam is so much better than street level & the gopro size is too unstable, a keychain cam may suffice. The only way a gopro replacement could materialize is for a handheld gimbal movie or if there was a way to protect it without a full enclosure.
Posted by Jack Crossfire | Jul 02, 2017 @ 04:34 PM | 2,900 Views
Replacing the knots with clover hitches & trucker's hitches got polecam 1 a lot more rigid. The entire rigging became a single length of string. It was about as rigid as solid carbon fiber. The mane problem with solid carbon fiber is the attachment points would have flexed. It really is a problem only 3D printing or multi axis milling could solve. A 3D printed coupling would have then been heavier than string.


Experience & SpaceX photos have revealed you can't drill small holes into carbon fiber. Loads applied to it have to be spread over a large area. It can only be bonded to adhesives.


The video was as stable as a pole cam could get. The rigid pole didn't oscillate any more than the steering did on its own. The string dug into the plastic & started loosening anyway. The gopro needs heavier string, but this requires removing more material. Because of the need for stabilization, a long form video would be low definition, so it would be better done with a pinhead camera.


Polecam 2 (3 min 32 sec)

Posted by Jack Crossfire | Jul 02, 2017 @ 01:54 AM | 3,195 Views
Polecam 1 was a failure. The rigging came loose, allowing it to oscillate. The erratic steering amplified the problem. Even a perfectly rigid pole might have oscillated.


Polecam 1 (1 min 57 sec)