Tuesday, August 30, 2011

Emergency Line Cutter

Useful for emergency release from a line entanglement, or a scenario where you need to cutaway from your harness or wing to prevent injury: such as getting dragged by a wing into hazards like vehicular traffic, or into water, or over a cliff, or through rough terrain.

Other potential problems might include water immersion, or a conflict between your wing and your reserve chute.

A nice selection of PPG line cutters can be found here at ParaGear.com:

Useful kit, but purpose designed knives and cutters for the skydiving/PPG/PG industry are priced at a premium, despite most of these tools being essentially the same as those made for other purposes.

They are also sold in specialty scuba stores as line cutters, at specialty rates, because of the limited nature of specialty markets.

The price comes down considerably, however, when sold in the Business/Industrial community as band or strap cutters, or for tools to strip the plastic wrap off of sealed pallets of shipped goods.

Selling them to fire and police personell as seatbelt cutters brings the volume up, and the price down, but specialty designed seatbelt cutters tend to have narrow mouth openings, and will only grab one or two lines at once, and make slower work of cutting away a paraglider, or reserve chute.

Despite working in EMS/Fire Rescue, I've never been fond of the all metal bladed hook knives, because I've never been convinced that a steel blade will outperform a clean, unused razor.

If a user succumbs to the temptation to test cut even one line sample with his expensive Gerbing or BenchMade hook knife, he will have degraded its potential usability in a future emergency, as these knives can't be sharpened by their owners. I heard that Gerbings will resharpen their blades for free, if you mail them in, but the number of lines that a newly sharpened knife of this type will cut is limited. It's also true that the number of lines that a razor will cut is limited too, but I'm betting the razor will out cut a steel hook like the one below.

I know some people will disagree. My view is purely a personal prejudice, and based only on the experience of one Swift Water Rescue Tech I spoke to who had trouble cutting some 8mm hemp rope.

The best, and cheapest substitute I've found is this one, fur worker's tool called a tail skinnner.
It has all the features of a PPG line cutter witht the added advantage of a wide mouth to catch a large number of lines into the razor area. Confirm the length of the tool you that purchase, as some of these tools are quite small, in the 3.5" range for example, and may not be ideal for people who wearing gloves, or with large hands.

Saturday, May 28, 2011

Gopro tips and techniques

A lot of this info was sourced from internet user's groups including the Gopro user's forum site http://goprouser.freeforums.org/index.php and from the Facebook GoPro discussion forum: http://www.facebook.com/board.php?uid=50043151918

GoPro direct number 415-738-2480 SF Bay Area Pacific time. Or toll free 888-600-4659

If you are a new user - Very good how-to videos from Eyeofmine a GoPro distributer: http://www.youtube.com/watch?v=eaBByvLlIzw&feature=related

Average recording times from GoPro::
1080p: 12 min/GB
960p: 14 min/GB
720p: 16min/GB @30fps;
720p: 11 min/GB @ 60fps

Average capacity for 32GB of memory:
r1 - 8h 09min at 60fps (WVGA)
r2 - 8h 09min at 30fps (720p)
r3 - 4h 21 min at 60fps; [720p]
r4 - 5h 26min at 30fps; [960p]
r5 - 4h 21min at 30fps [1080p]

The battery will be the limiting factor as obviously the battery (2.5 hrs) will be exhausted long before a 32 GB card is full.

R1. lowest setting WVGA (Wide VGA format ) @ 60fps - 16:9 format 800 x 480 Good for long play medium quality. surveillance home/car etc (with external power pack or battery) Youtube posting at 480p.
R2. High quality Static or Low Motion shots in full 170 degree wide angle (Cam not moving much)
R3. High Quality High Motion, half the "jello" wobble (flickering) of all the other modes, full 170 degrees, smooth playback on TV, useful to retain smooth slow-motion in post processing.(.5 or .3 is best)
R4. Useful where a Tall Field of View is desirable (like mounted on a surf board looking at you standing up) The r4 setting corresponds to 4-3 format. (old school TV screen) r3 - r5 are more like 16 - 9. (movie screen format))
R5. Full 1080p resolution, ideal if you want to crop and zoom sections of the frame, only 120 degree wide angle. Lots of jello effect, unless camera is stationary mounted, or isolated from vibration by positioning, foam, etc. Huge files. Many computers, especially laptops have problems storing and editing the HD.

Most people recommend r3 for fluid motion filming. Biking, races, etc. but I've been shooting in r2 because paramotors move sort of slowly, and a helmet mounted camera is somewhat isolated from vibrations compared to a track bike. Also, I edit in imovie, and the latest imovie (11) still doesn't support 60fps. It drops it to 30 anyway, so I figure why not shoot in 30?

One argument for r3 is that r3 makes for great slow motion, and imovie can cope. There is also a fix for dealing with 60fps in Final Cut, and imovie if your editing skills are up to it, however, see MAC TIPS for software upgrades.

TIPS.Use good quality SD cards. Gopro recommends Kingston and Patriot cards in class 4 or higher.

Spare batteries are inexpensive - averaging about 25 dollars. So why not have a spare?

Turning on the camera. It takes a second to activate, so many people hold the button too long. Just give one quick push of the power button and hold your breath. Don't hold down the button and wait till you hear beeps, or you may turn on some other function other than camera, as an accidental second push, or a glitch, may cause the camera to advance to a different setting mode. This is pretty easy to do.

Turning the camera off. Do hold power button firmly until you hear beeps.

The use of an SD card reader is strongly advised for the protection of your media as opposed to direct computer transfer via USB from your camera. Card readers also speed up image transfer by as much as 4 times. SD card readers are inexpensive (as low as ten dollars) and are a manufacturers recommended item both to prevent lost media, and for camera longevity.
-You are saving wear and tear on the USB port on the camera.
-When using the camera as a card reader, the transfer is using battery power, and only a finite number of battery recharges are possible. Also, when battery levels get too low, transfer can be interrupted.
-Few pro's would ever connect any DSLR direct to computer via USB. It's considered a bit of a tech no-no.
-Some computers don't always read the USB linkage of the GoPro as a card reader, and data corruption has occurred in transfer.

The use of an external WALL or CAR CHARGER is recommended rather than using your PC to charge the Gopro. You can charge, the unit from your PC but it is not as safe as a dedicated wall charger. Also a wall charger charges twice as fast needing only two hours for a full charge compared to four hours on a CPU. The GoPro Forum site administrator says if he had to give ONE piece of advice to GoPro users this would be it: "An Iphone (not ipod) charger is perfect using a standard USB mini to to full size USB cable (like the cable for portable hard drives) so is any other 5v/1A charger as well as car cigar plug USB chargers. My GoPros NEVER go near my PC full stop."

Card readers and battery chargers are both really quite inexpensive. Special battery only chargers are available to charge the battery alone, either by wall or by car, and this allows you to use the camera while your spare is being juiced. This also saves wear and tear on your mini-usb plug on the camera itself.

Hey, and this guy seems to work too! http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... K:MEWAX:IT
It's only $5.98 including shipping from ebay. It is for slightly larger batteries, but the 3-pin connectors fit okay. One report says to charge it for a while longer, past the full light indicator.
I just ordered one. I'll post my experience with it as soon as Canada Post is back in business after their current labour disruptions still ongoing as of July, 2011/

Update: Okay, so far so good. It appears to be the same gizmo as the RPM Gear above, priced at $18.95, and by RageCams for $34.95. Just in black instead of white as in the site photo. (But they say color may vary.) The main thing is, the specs are the same, output at 350 mA.

It has a USB output, so evidently you can charge another device at the same time (even another GoPro) using the same wall plug.

These devices are 2-pin, and not 3-pin, but nevertheless still charge up fine using the bottom (+) and the middle (-) contact slot. Just ignore the top contact slot on the battery. Someone said the third (top) contact is also negative, but whatever, the battery still charges.

Users of these devices suggest leaving the battery in the charger for a "little" (unspecified) longer after the light goes blue, to maximize charge.

The units described in the RPM site say the charger has an intelligent chip to prevent overcharging.

Then if you haven't already done so, pick up a USB car charger and you're ready for anything. USB chargers are only a couple of bucks on ebay, or splurge for this guy, at $9.99 shipped, http://cgi.ebay.com/Griffin-PowerJolt-Dual-USB-Car-Charger-iPhone-4-3GS-/330563176863?pt=PDA_Accessories&hash=item4cf719c99f#ht_3523wt_907
which is by Griffen Technologies and Apple approved. It will charge your GoPro and another USB device at the same time.

Apple iPhone chargers work perfectly, as does the Apple clone charger that I got from China via ebay. I've even seen them at the local dollar store.

Lens care and fogging issues:
-The proprietary anti-fog strips that GoPro sells, are pretty expensive, and tiny bits of commercial chamois like Sham-Wow also work. The GoPro forum has a number of people who find slipping a couple of grains of dry rice into the case works also. While I have concerns about nearly microscopic flakes of rice dust being a problem, these users say it works okay.
-Apply RAINEX to front of lens, (a single drop and polish carefully) You might have to take unscrew the five screws to do a perfect job of it, but that only lakes a minute or so to take apart and reassemble. (Watch which way the gasket faces when you take the lens out.)

"Cat Crap" Lens cleaner gets high marks from users for this purpose as well. These products fill the microscopic 'pores' in the glass surface making a smoother surface which water is less prone to bond. Anti-fog can be rubbed on the inside surface of the lens and case, but ensure the product is suitable for glass when applying it to the lens. Some anti-fogs are not recommended for polycarbonate. Weak dishwasher soap will also work, (an old scuba trick) but needs frequent reapplications.

-In high humidity areas, The Gopro Forum moderator suggests drilling a 5mm hole in top of case, and epoxy a bit of GORTEX over the hole. Cam now 'breathes', but remains nominally water resistant.

-Bubble lens of case is made of glass. Case is polycarbonate.

-Storage/and travel: Solution to lower the moisture content of the case and the camera to a stable level.
Put the Gopro camera in a sealed plastic bag or air tight container with a desiccant pack and store it permanently that way. Place the housing only in cloth bag (an old sunglass bag is good and allows case to breathe) with desiccant pack inside the case and closed fully. Store and transport it that way. Keep both out of direct sun until ready to assemble and use. When you arrive at the filming location, quickly place the GoPro in the case and close it, being careful not to have sweaty or wet fingers.

-If desiccant is not available, some people enclose the camera with a cloth bag containing rice to absorb moisture.

-Desiccant sacs can be re-dried in an oven, and reused multiple times.

-For cold weather, cool the case to ambient temperature for 5 to 10 minutes, and use fog strips.

The camera can get hot, especially when using the waterproof housing in hotter temperatures. Overheat can be the cause of some data corruption, and is hard on the camera. The non-waterproof housing vents heat better, is less fog prone, and the sound is better.

The sound ports are at the back so the operator's speaking voice will be louder than the subjects.

Firmware up to date? Go here for tutorial help: http://pointofviewcameras.com/gopro-hd-firmware-upgrade
imovie will not recognize 60fps so will drop it down to 30.
Fixes available for imovie or final cut - http://contour.com/stories/60fps-into-slow-motion-using-imovie-09
-Empty trash, or the card may not be erased
Also streamclip is recommended by both gopro and mac

This page helps http://www.pashnit.com/forum/showthread.php?t=25628

ifishfix action works is available to remove the curved effect of the wide angle, with 98% fidelity

Some interesting developments involving goPro lately.
Not every one likes the 170 degree appearance of the GoPro HD. It makes close ups of faces look funny, and sometimes you get noticeably curved edges on horizons or otherwise straight lines.

Some of this curving can be fixed in post, using the free download software above, but the radio control FLV RC aircraft crowd found a physical mod using a 6mm lens from Sunex that gives a more natural, non-fisheye look, if you want that.

Ragecams, a helmet cam distributor, now sells a few different lenses that can be home-modded into the camera, or they swap out the lens for you for a small fee. Their most popular lens is a 2.3mm lens with a fairly wide (I think it is about 120 degrees) field of view. They also have 3.6MM, 6MM, 8MM, 9MM, 12MM and 16MM and the field of view gets narrower as the size increases.

Tentative reviews seem to favor the Ragecam mods, in part because most of the above lenses fit into the stock waterproof housing, without any further modification to the case. It looks to be a bit of a chore to remove and replace a lens, and not something you’d want to do away from a clean bench and a light, but the lenses can be switched around, and back and forth.

The lenses average about 75 bucks from Ragecams, or on their ebay site.

GoPro says they have no plans to change the HD and allow for factory installed alternate lenses of other sizes apart from their standard HD lens, but I’m betting they will start doing so before long, if Ragecams starts selling mass quantities of their lens packages.

There is also talk of a remote viewable LCD mod in the works, and also a remote microphone using the back port on the cam. (If not from GoPro, then from aftermarket developers as the home mod guys are already tinkering with them.)