RunRyder - First Try at aerial photos

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Aerial Photography and Video > First Try at aerial photos

Mark Johnson
Senior Heliman
Location: Ont. Can.

I have a raptor 30 helicopter.
I tried today for the first time to get a snap shot from the skies above.

I installed/ mounted my digital camera to my raptor, set the timer and lifted off.

I did some hovering and controling of the helicopter before I went high, I wanted to get used to the feel of the extra weight.

I thought the raptor30 with a 0s 32 engine handled it quick well.

I mounted it just under the main tank, it was strapped to the supports and the skids.

Well, the first photos did not turn out very good, the smoke from the engine was very noticable, even though I had an exhaust deflactor on, but the smoke was in each picture, and sometimes that is all Icould see... smoke.

Any ideas on how to mount it, maybe on the nose of the helicopter?

any tips of suggestions from you experenced photo guys/gals?

09-25-2003 Over year old.

Mark Johnson
Senior Heliman
Location: Ont. Can.

Does anyone have any advice for a newbie in this area? Any obvious things you could recommend while starting aerial photos?

09-27-2003 Over year old.

ELOSSAM
Veteran
Location: Es

Mark, As you said, a nose in mounted camera will help the smoke effect, a larger muffler extension too but with enough diameter not to force the engine. A gasser makes usually less smoke but sometimes more vibrations too. The lift power of a gasser gives you more margin to add more and more devices. Flyboy used sometimes a 30size heli and sure he can tell you more as soon as he has time.
Cant say nothing about the TSK heli. if it´s still on the market and you will not have spare problems then you can start with it but the new machines with the last generation gas engines worth if your seriously considering it as an investment. VARIO, XCELL, BERGEN ... there are many models to be choosen and each one has different oppinions about them. If I should start again from "cero" I should choose the VARIO one. The other ones has few representation in my country.
Elossam

09-27-2003 Over year old.

HOMEPAGE

tech1
Senior Heliman
Location: Mississauga

Go ahead and mount the camera on the front.

There are 2 types of movement that will cause problems.
1. High frequency vibration from the mechanics of the heli. you need some kind of vibration dampening between the camera and the frame of the helicopter. For me this was the easy part to do.
2. Low frequency movement. If you can't hold the helicopter absolutely still and the shutter speed is too slow........ you get a blurry shot. Same as if you turn your body while photographing something. This is the more difficult problem for me as my helicopter tends to wander a little.

If you have the money, go for a bigger ship.

Best of luck.

09-28-2003 Over year old.

kevinbuckley70
Senior Heliman
Location: Oxfordshire, UK

"High frequency vibration ... this was the easy part to do"

How? - Regards, Kevin

09-28-2003 Over year old.

Angelos
Key Veteran
Location: nr Oxford, OX11, UK

Quote
Low frequency movement. If you can't hold the helicopter absolutely still and the shutter speed is too slow........

Do you enjoy constantly throwing the heli back and forth while taking the photos?

If the motion doesn’t repeat then you don’t have a frequency. I guess you mean just movement.

Regarding the frequencies of the vibrations infolded you have three easily defined frequencies…
1. Engine RPM
2. Main Rotor RPM
3. Tail Rotor PRM (I presume that an unbalanced tail, bent shaft for example, would create vertical blur on the photos).

I don’t know how engine vibrations (unbalanced fan for example) and main rotor vibrations would show on the photos as I didn’t have problems so far. Anyone else please comment.

All three frequencies are related and you can calculate one from the other using the gear ratios. If you are running a GV-1 governor then you can precisely key in the RPM you want and you can have predictable values for all vibration frequencies.

I have used a 10G chip accelerometer from analogue devices with a cable to a portable oscilloscope and took my heli in 2 feet hover. Then played with different RPM using the governor to find the frequency where my camera mount tunes and avoid it.

-Angelos

09-28-2003 Over year old.

tech1
Senior Heliman
Location: Mississauga

I went with aluminum crossbars that mount where the frame meets the skids. Two long pieces of aluminum run front to back on the heli. I used silicon grommets from a CD pickup tray between the cross pieces and the long pieces to reduce vibration.

The long pieces run all the way under the nose of the helicopter where the camera is mounted to a U bracket. I got the idea from one of flyboy's photos of his 30 size camera ship.

Take lots of shots and slowly change settings like RPM and pitch and your flying style and direction. Keep what works and forget what doesn't.
Learn as you go.

09-28-2003 Over year old.

Angelos
Key Veteran
Location: nr Oxford, OX11, UK

Kevin,
any nice places to take aerial photos in Oxfordshire? I have only moved here in February so I don't know much. I took photos of a church yesterday by the river (Thames I think). I have no idea where I was, it just looked good. Perhaps you will recognise it. Must be fairly close to where you live.

-Angelos

09-28-2003 Over year old.

MPA
Elite Veteran
Location: Australia

Quote
I don’t know how engine vibrations (unbalanced fan for example) and main rotor vibrations would show on the photos as I didn’t have problems so far. Anyone else please comment.

Set your stills camera to 1/50 and shoot away, if its blurred in all the shots then you have vibration.
If its decent you should get a number of clear shots.
Video is sensitive to the lower vibrations so seen on slow motion as an obvious wobble.
Id advise to test using the above methods on video at slow motion playback speeds and on stills at low shutter speeds.

If both of those come up like glass in every frame or shot then your a winner.

09-28-2003 Over year old.

HOMEPAGE

flyboy
Elite Veteran
Location: California

"A camera is simply an optical tool that measures the vibration of a given platform."

If it moves try to balance it. Good luck & keep us posted with your results.

09-29-2003 Over year old.

Angelos
Key Veteran
Location: nr Oxford, OX11, UK

MPA, flyboy,
I was trying to identify how different types of vibration would show on a photo.

For example a tail rotor creates only vertical vibrations on the tail and thus I would also expect to see a vertical blur on the photo. I would expect a bright spot (street light or sun reflection) to show as a vertical line.

Similarly (perhaps I am wrong on this)... a badly balanced main rotor would have a static or dynamic force that moves around and this in my opinion might cause a street light to show as a circle (providing the exposure time is long enough).

I have no idea what effect an unbalanced fan would create. The above is only theoretical. I have no vibration problem in my system but we could work out some rules that identify the vibration source. Any thoughts?

-Angelos

09-29-2003 Over year old.

flyboy
Elite Veteran
Location: California

That is a slippery watermelon. I try to minimize/eliminate all or as much vibration as possable. Yes you can tell the differance between low, medium and high frequency vibration, and the effect they have on video and image quality. I start by balancing everything, spend some time getting the platform dialed and then install the camera & mount.

Fire her up and go from there.

I had a lot of luck installing a laser pointer on one of my camera ships, hovered /go light on the skids and recorded the image of the laser against a wall with a video recorder. I could then experiment with different blades and head speeds and see a dirrect relation between the "dancing" of the laser.

Spend as much time as possable getting the platform dialed and go from there. Camera, electronics and still/clear images all HATE vibration.

09-29-2003 Over year old.

Mark Johnson
Senior Heliman
Location: Ont. Can.

great feedback....

It is good to get this feedback.

Thank you.

09-29-2003 Over year old.

Angelos
Key Veteran
Location: nr Oxford, OX11, UK

Flyboy,
Hmmmm, laser pointer … great idea. By the way, I though that my camera man was the only nutter to put the video link RX on a hat but looking at your gallery he is nor alone

09-29-2003 Over year old.

kevinbuckley70
Senior Heliman
Location: Oxfordshire, UK

Angelos

Sorry - I don't know many churches in the area - only lived here 5 years myself. Maybe Dorchester Abbey?

"Kevin - any nice places to take aerial photos in Oxfordshire?"

Probably lots! I would suggest Henley-on-Thames (lots of field for take-off & landing - Remenham Meadows for example?) or Goring/Streatley.

Both very picturesque.

Regards, Kevin

09-29-2003 Over year old.

MPA
Elite Veteran
Location: Australia

As was said already Angelo
Do all the basics and balancing and keep at it, the more time at it the better result and the cleaner the images, the more range you have with the camera.

While there is certainly 3 predictable axis of angular vibration in the heli and there is 2 axis of torsional vibration.
It all adds up to a nasty mix when the torsional translates to angular adding to the 3 there already of various frequencies you mention.

As you know the higher frequency 1st order is simpler to deal with, mix a few in with other order vibrations and it gets a bit convoluted in the sums
A stick or pointer is simpler than maths and accelerometers.

In short just keep dialing in the shakes, use a laser or wobble stick, the laser is a better idea if you have one.
Keep at it till its good to go, the camera will give you the final result so run it range of usage and make sure your getting what you need.
If you have to run 800 to 1000 speed all the time for stills you wont have much room to move and you can forget glassy video.

09-29-2003 Over year old.

HOMEPAGE

flyboy
Elite Veteran
Location: California

Yea we are all nuts here on the West Coast.

I had to get creative as i could not always(almost never) find someone willing to hold the antenna and push the trigger.(with the "little Bird" recreational system. Offer $, and that is a different story. It is a boring unglamerous job and I found myself having to improvise at times.

Not a pretty picture while it is happening, but the results usually make it worth the effort.

If this was easy the girl scouts would be doing it.

09-29-2003 Over year old.

Angelos

Key Veteran - Location: nr Oxford, OX11, UK -

flyboy,
is that observer with the orange stickers yours? I like the colours... I just finished doing my Raptor 60...

09-30-2003 Over year old.

flyboy

Elite Veteran - Location: California -

This is a picture of the Observer that I used to fly.
I have since purchased several of the airfoil mounts which I find to provide equally as nice still photos and the most unbelievable video that I have ever seen.

The folks at bergen and their support is some of the best in the buiz, but the video that the observer produces, has plenty of room for improvement.

These are hard to see in the air. I found that stickers and foam on the skids helpful for orientation.

Flyboy

09-30-2003 Over year old.

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Aerial Photography and Video > First Try at aerial photos

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