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Posted

I know this has been discussed somewhere in the forums here but I can't find what I'm looking for....

 

Anyone who has seen any of my video clips will notice the prop blade distortion patterns in the footage. What I want to do is avoid this when I buy a new camera. What do I need to look out for in the camera specification that will ensure I don't have this problem in the future?

 

Simple question, but does it have a simple answer?

 

Cheers,

 

Pud

 

 

Posted
I know this has been discussed somewhere in the forums here but I can't find what I'm looking for....Anyone who has seen any of my video clips will notice the prop blade distortion patterns in the footage. What I want to do is avoid this when I buy a new camera. What do I need to look out for in the camera specification that will ensure I don't have this problem in the future?

 

Simple question, but does it have a simple answer?

 

Cheers,

 

Pud

I'll do some research when I get time Pud, but I believe that cameras with CMOS image sensors have this effect, although newer ones may have fixed the problem. In a CMOS each movie frame is scanned pixel by pixel over time ( a bit like reading the page of a book). So fast moving objects appear distorted (such a props) because the object has moved over the time taken for each frame to be scanned and downloaded from the sensor.

CCD image sensors don't have this problem because all pixels in the frame are taken at the same time. CMOS sensors have always been cheaper so they are used in most consumer grade cameras/phones....but their quality is now just as good or better than CCD I think.

 

 

Posted

Check out Aviation Geeks podcast, I think two or three weeks ago. They had a guy on from http://otherpeoplesairplanes.com/. He was discussing exactly this thing. Can't use a gopro for over the nose due to the prop distortion. Have a listen to the podcast ior check out his blog for sem setup ideas. Sounds like he is happy to respond to emails about the setup also.

 

 

Guest pookemon
Posted

The following video was shot with a GoPro at 720p/60fps. The distortion that you typically see is not there - the prop looks like a prop rather than some weird artifact. The GoPro will do 60fps in 720p and 120fps at WXGA (which is essentially DVD quality). I haven't tried the 120fps yet (might do so on the weekend). The one down side to the GoPro is the 170 degree fisheye - which I've corrected in this video using a distortion plugin in Adobe Premiere.

 

 

Other than the field of view, and the distortion, the GoPro also deals with contrast and low light alot better than the Panasonic. Plus the GoPro has a number of different mounts for different situations (including mounts that can be used on the outside of the A/C).

 

 

Posted

:smile:Hey Pud,

 

Check out N Flight.cams.com its a USA Company Guy that makes aviation related Cams mate........ he has a cam that takes a special lense that completly elimates the Prob Blur all together...........Looks like a good Product thinking of getting one myself.......

 

Cheers John H.

 

 

Posted

I have a Panasonic full HD video camera. It hardly sees the prop but a horrible 'wavy' distortion makes it useless for flying video. My Contour HD takes goood full HD video without distortion and although you see the prop, it is not that bad. The prop distortion is a function of the way the sensor scans rather than the lens.

 

 

Posted
I have a Panasonic full HD video camera. It hardly sees the prop but a horrible 'wavy' distortion makes it useless for flying video. My Contour HD takes goood full HD video without distortion and although you see the prop, it is not that bad. The prop distortion is a function of the way the sensor scans rather than the lens.

Thanks mate only going on what I see on their web site & their Demo Videos ....... looks good to me!

 

 

Posted

What about mounts - should that be a separate thread? i have a Nikon coolpix that takes decent enough video (not sure about the prop effect), and has the standard threaded hole for tripod, etc.

 

what are you guys using to mount your cameras? Any thoughts on what I might use for a standard small digital snapshot camera? I was thinking perhaps about something that would clamp to the passenger headrest, or some part of the structure. Only thing I have really been able to find at Dick Smiths are those flexible gripping mounts, but not sure those are stable and sturdy enough?

 

 

Posted
kinda answered my own question, something like this might work - but still keen to know what you guys use/what works.http://www.camzilla.com.au/products_info/clamp-mounts__standard-clamp-mount-base

I just use a stock standard suction mount attached to the polycarbonate fuel tank viewer between the seats in my T500. It has the standard screw fitting that most cameras have and seems to work well enough - wouldn't use it externally though. When I did position the camera out on the wing strut I just taped it on with insulation tap - pretty rough and ready but it worked well enough.

 

If I was to get serious I would look at something like what your link shows.

 

Pud

 

 

Posted

Wow Jake, that looks like a beautiful flight though! Agreed, the prop distortion is distracting and generally unpleasant, but looking past that... wow! And what are you using to hold it, is that a helmet mount?

 

 

Guest davidh10
Posted

I use a home fashioned camera mount, as pictured here. The wavy distortion mentioned by J170Owner is I think what I initially had with my canon HDS20 (1080p 25fps @ 24Mbps). It disappears when hand held, so my conclusion was that it was engine vibration interacting with the camera picture stability features. My solution was to modify the mount to semi-float the camera. Almost fixed, but you be the judge.

 

P.S. No prop distortion. Although mine is behind me, when I film other aircraft up close there's no problem.

 

 

Posted
Wow Jake, that looks like a beautiful flight though! Agreed, the prop distortion is distracting and generally unpleasant, but looking past that... wow! And what are you using to hold it, is that a helmet mount?

Thanks. Camera was just stuck to the dash next to the magnetic compass with blu-tac. In future I will try and mount it further back, possibly behind me which would give a bit better field of view.

 

 

Guest ozzie
Posted

If you are considering a Go Pro make sure it is the new "2" version.

 

 

Guest pookemon
Posted
kinda answered my own question, something like this might work - but still keen to know what you guys use/what works.http://www.camzilla.com.au/products_info/clamp-mounts__standard-clamp-mount-base

I have one of those, but it has an extra piece that allows you to changed the angle of the camera (has a ball joint on the end of it). They're quite sturdy - the body is metal and the the clamp is nicely shaped to go on CrMo tube. And it doesn't shake around once fitted.

 

The GoPro comes with a variety of mounts for both inside and outside the A/C. Sticky mounts can be used outside the A/C (depending on the covering) and most A/C will have something you can clamp one of the handlebar/rollcage type mounts to (like struts etc). They don't use a normal tripod type mount (though you can buy one of those if need be). And there's suction cup mounts, head mounts, chest mounts etc.

 

 

  • 2 weeks later...
Posted

we use Contour HD's on our race cars with outstanding results, no vibration or distorted video. Sporty's in the US sell a Contour cam called NFlightcam Plus and claim it cancels out prop distortion. Most probably available here if you look around.

 

Steve

 

 

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