Menu Sign In Contact FAQ
Banner
Welcome to our forums

Garmin enters the movie camera market

here

These are better shaped than Go Pro, for external mounting.

Administrator
Shoreham EGKA, United Kingdom

I took the Garmin rep float flying, and he had one of these (one of five, he told me). It was excellent, I can’t wait….

Home runway, in central Ontario, Canada, Canada

The problem with all these cameras is the ‘rolling shutter’ induced by vibrations, if mounted outside and shooting 1080. Pretty much impossible to get rid of with the GoPro. Will be interesting to see how this one deals with the issue.

The frontal area is almost the same as the GoPro and GoPro seem to offer better specs.

EHLE / Lelystad, Netherlands, Netherlands

With connection to your D2 pilots watch. lol

Ukraine

I would be amazed if Garmin didn’t try to do something about this – because the prop effect makes all those youtube videos as cliched as a 1980s poster done on Pagemaker and utilising every one of the 27 or whatever fonts that came with it

Unfortunately the only solution that actually works fully is a shutter speed slower than about 1/100 (the actual figure is RPM dependent). This is available on the more expensive “prosumer” camcorders. I have a Canon Legria G10 which, when I bought it 2-3 years ago, was £1500. That level of video performance is cheaper today, and actually my £350 Nokia 808 phone (~40 megapixels) probably delivers a comparable 1080P raw video quality in good light and mounted on a tripod, but the camcorder makers continue to use stuff like manual shutter speed to mark the “consumer” v. “prosumer” market boundary. For example this video is free from prop effects once the RPM is in the cruise range, and I could have used an even slower shutter (at the cost of more image blurring) to make it effect free even at idle.

However I have no idea whether this can be achieved in these cheap cameras which probably all use the same CCD/CMOS sensors.

Last Edited by Peter at 21 Nov 08:10
Administrator
Shoreham EGKA, United Kingdom

Peter – easy. Just stick an ND (neutral density) filter on.

That’s not ‘rolling shutter’, however. Rolling shutter is the ‘jello’ effect you get from rapidly moving a sensor while it records an image. An image sensor (and, in fact, most film camera shutters) do not expose the entire image in one go, rather they very rapidly move from side to side or top to bottom. Thus, one part of the image is exposed slightly before the rest, leading to a strange deformation effect. If this is repeated rapidly, you get the most amazing wobbles in the image. Some cameras handle this better than others and you have to go pretty high up the food chain (way out of prosumer territory) to find machines that use traditional sensors and don’t suffer from that effect. GoPros unfortunately are very susceptible to this effect, especially at the 1080 setting. They are fine at 720. Currently the only way to avoid it is to use something called a global shutter. At present, the only cameras I am aware of using it are a couple of high-end Sony production cameras and a handful of specialty-application cameras. There are a couple of lower-end machines in development, but none are on the market yet.

Surely the problem is associated with frame rate versus rotation speed. Two rotating objects will always produce a beat or video effect when the difference between the two is within the capture range. You could electronically compensate for this but to do so you would need to sense or measure the prop rpm. Another reason for a constant speed prop.

A few years ago I was involved in flying an aircraft filmed by the BBC for a TV program; when they examined the video it contained a marked strobing effect which they thought was caused by a radar or some super techo device; my son a video editor looked at it and said, they have an out of sync monitor running near the camera!

Surely the problem is associated with frame rate versus rotation speed.

for Peter’s issue, it’s shutter speed (frame rate does come into play, but shutter speed is the determining factor).

ND filters are the cheap and quick way of improving things because they slow down the “shutter” of the GoPro-type “webcams”, but they never seem to quite remove it, IME.

Yeah… one could do the “through prop machine gun solution” and sync the camera to the prop, but that would need a 2B (not 3B) prop and you would have to sync it when the prop is horizontal. Then you would need to interpolate the frames to produce a video at a constant 25FPS.

This suggests one can get a global shutter on some small-ish cameras.

for Peter’s issue, it’s shutter speed (frame rate does come into play, but shutter speed is the determining factor).

The frame rate will surely always be constant, unless you are happy to always post-process to 25FPS. The shutter speed seems to be all one can play with easily.

Last Edited by Peter at 21 Nov 09:59
Administrator
Shoreham EGKA, United Kingdom
25 Posts
Sign in to add your message

Back to Top