Camcorder "Coaching"

Video technology changes so quickly the archives were not as useful as I had hoped they might be, for learning how to use a camcorder for CL flight videos – as an always available “coach”. From references in various threads, many of you use camcorders to record in-flight action. Not surprisingly, there was zip in the Product Review archives regarding camcorders.

My basic question is what are the things you have learned as a basic setup, such as camera position, hand-held vs tripod, maneuver tracking, detecting trim problems, and general usefulness.

I played with this idea a few years ago with a bulky VHS camera that took full-size VHS tapes. Not exactly stellar results. With modern camcorders, I have higher hopes.

Seems like the standard setup might be to put the camcorder outside the circle on a tripod pointed downwind (where the judges would sit). Right or wrong?

Another idea I didn’t see anyone mention was setting the camcorder on a low tripod near the center the circle. That should make for good video, especially the times you trip over the tripod. ("No thanks" to the camcorder on the helmet idea)

The most obvious solution is to plant my big, strong, handsome wife in a “judge’s chair” position and have here point straight downwind most of the time, with a mix of following maneuvers depending on what is in the viewfinder.

I like the accurate timing aspect. One should be able to detect minor changes in lap times with prop changes, settings, beginning to end of run, and that sort of thing. We took a two minute video of a stopwatch, and the Mini DV playback was one-for-one with the real watch.

For equipment, we are looking at low end camcorders (1/6” CCD, 20X, Mini DV format – Sony DCR HC-26, Panasonic PVGS39, Canon ZR 800 -- $300 plus or minus). Are camcorder in this range suitable for our purposes, or do we need to go a little more high-end? Transfers to DVD, editing capability, and other video niceties are not essential, and my son can bail us out on that front if necessary. Getting enough resolution to see elevator deflection in a maneuver is just a pipe dream, right? Is tape speed a consideration?

I am assuming finding a zoom setting that will capture most of the pattern with the camera fixed is possible? How do ya’ll handle the overhead 8 and the vertical maneuvers?

Most important question is, do you find the videos useful, helpful, or is it just another danged toy?

Edit Add: If anyone is willing to zap me a file snip of a video, that would be nice, even if you have to "dumb it down" a little. I am at [email protected].

Larry Fulwider

Hi LArry.

I found it very useful. I used a couple of old sony Hi-8 machines I resurected from Eba*.

The only problem is getting a large enough field of view from a normal judges position. To do this, you really need to use a wide angle attachmnet that is a lens fitted over the one in the camcorder.

Even without this tho, you can get helpful information.

Put it on a tripod and set it so you can just see the ground downwind. I like to have three reference poles set up as well--at a minimum, some fixed reference in the background so you can judge heights.

Then jus let it run. Back it up after a few tries as required to get the manuevers in frame.

The wingover and overheads are a problem and camera needs to be repositioned.

Don't overlook using a 90 degree circle position so you can judge sizes. A really long view can get the track of the wingover.

Using a camer hand held and moving to get the full size is nearly a waste of time.

Be careful of using grease pencil on the TV screen! some of the anti-glare coatings make it very difficult to remove!

HAve fun.

PS..I've used 3MB digital stills to judge flight trim initially.

CUrt

A cheap (inexpensive) camera should work just fine. You don't need (and won't use) zoom. The biggest problem is backing away. I wish they would make them with wide angle zoom.

And you don't want to follow the maneuver. Without the reference points this becomes almost useless. Just set the camera up on a tripod far enough away that you will get the entire square eight and verticals in the viewfinder. Then set it to run and go for it.

I have been on camera duty a few times when Matt was flying and would merely turn it on and shut it off. Then I would do my normal thing of watching from the judges view and watch for mistakes. It is a good process in being able to point out the repeated errors and then allowing the pilot to see them for himself on the screen.

Also time your laps and time your maneuvers. The time for the reverse wingover and two level laps ought to be near equal. If the wingover is faster, the engine is kicking in too much. If it is slower, the plane is slowing down in maneuvers (normal for 4-strokes). See if you can keep a steady count on the square eight. Also time the square eight. We run about 13.5 to 14 seconds for the complete maneuver. This will depend on your lap time, however, so yours may vary. If the engine is slowing down or your make the maneuver too large, the time will get longer. And if you hurry through it, well, see what it looks like on the camera.

I tried shooting a few flights once and was amazed at how far back I had to put the camera to get the entire flight. I didn't have a wide angled lens.

>I tried shooting a few flights once and was amazed at how far
>back I had to put the camera to get the entire flight. I
>didn't have a wide angled lens.

That's why Matt always assigned those duties to me. You have to walk (or run) back to the camera to turn it on/off from the normal judges position with a standard lense.

I experiemented with my flying friend Brian and here are some of the results.

http://www.machineconcepts.co.uk/aeromodelling/brian/inside_loop.MOV

http://www.machineconcepts.co.uk/aeromodelling/brian/outside_square.MOV

http://www.machineconcepts.co.uk/aeromodelling/brian/vertical_eight.MOV

I used my digital still camera which can do short films - just enough for a single manouver. On a tripod and I had just time for the camera to save the short film and reset between each manouver. It is useful as you can step through the manouver with the slider. The resolution is rubbish but if you have the file on the computer rather than in a browser you can drag the size larger and take proper measurements.

I believe Bill Rich did ?/ does a ton of this and found it very
helpful

Thanks All! Extremely useful information. I would have made several false starts without your advice -- and annoyed the heck out of my wife telling her where to stand and what to do. I did find our old VHS tripod, which will work. I didn't waste money on more camcorder than I needed. Never thought about timing maneuvers -- very clever!

What more could you ask for?

(Note to Curt -- Thanks for the tip about not drawing on the TV screen. Not to worry, I still have my Winky Dink Magic Screen from the 50s, so I could draw bridges and ladders on the screen to save Winky Dink from the bad guys!)

Larry Fulwider

Larry,

There is an article on how to do it, by Bill Rich in and old Stunt News, somewhere around 2001 I think?

Jim Pollock

Hello Larry, Go to windy urtnowskis web site. I have dvds of his that show CL flying and all kinds of controlline information. Web site is windyurtnowski.com Good Luck George Eckhardt

I've watched several different brands of stunt videos, and found some problems that lead me to think it's maybe not very useful.
1) You need to put the cam on a tripod and set to widest angle possible, set the camera and let it run. Unfortunately, the wide angle lens appears to produce too much 'fisheye' effect, distorting the appearance of the tricks. Panning will make the video totally and completely useless.

2) Most models in most vids have been very difficult to see on the far side of the circle, where the tricks are done. A light & bright colored plane should help, but will it help enough? A bigger plane will help a lot. Keep the paint scheme simple. For example, checkerboard, viewed from a distance works a lot like camoflage. Big panels of one color helps. What may be the deal killer is that some sites, or in different seasons, you may need different colored planes to make them show up.

3) If you rely entirely on watching your own video of your own flying, you may not realize that what you are trying to do is not what the rulebook calls for, judging from the arguments about how the maneuvers are supposed to be done, on stunt forums. Therefore, it would be better to have a flying buddy that you can have coach you, and you coach him. Not always easy or succesful. Communication of the errors you see needs to be diplomatic, but clear and understood. I've tried it, and found it to be frustrating. Steve


Steve Helmick
Renton, Washington
USA

>I've watched several different brands of stunt videos, and
>found some problems that lead me to think it's maybe not very
>useful.

I know other people swear by it, but I have to agree - the few attempts I have made to try to use video were really not very useful. I saw problems that were not actually present, and missed problems that were there. This was with standard analog video. Maybe high-definition video would work better, but I haven't tried it.

If there were some way to do what Keith Renecle did here:

[photo not recovered: 15442.jpg]

in essentially real-time, THEN, you would have something!

Brett

Video is of very limited use because of inherent lens distortion (mainly barrel distortion that makes squares look rounded with soft corners). About the only things you can judge accurately from a video is bottoms and intersections. Shapes, size and corners all get very distorted by the video lens. The wider the angle and/or the cheaper the lens - the more the distortion.

Right now there is no substitute for a judge or a coach viewing the pattern in real 3D life. 2D simulators and videos can help but with this being a subjectively judged presentation the judge or coach still needs to see it in real 3D life.

Regards,
Dave Cook

Frank Carlisle
proud member of R.C.C.D

http://media.putfile.com/bi-slob-combat-frank-vs-fletch


I'm using a Panasonic 3CCD camcorder. Hand held let's me get the manuevers plus laps and stay fairly close. Telephoto starts getting jerking in the video and makes it hard to track the model.
The link above is a Bi-Slob combat match.

Brett said:

> If there were some way to do what Keith Renecle did here:
>
>[photo not recovered: 15442.jpg]
>
> in essentially real-time, THEN, you would have something!
>
> Brett

You got that right!

I just had a flashback. Back in the 50s (Flying Models, I think -- collectors, check your archives) there was an article titled "How Round Is A Loop?" with pictures similar to the above. Fascinating piece! The guy had a Berkely P-40, taped a pen light to the inboard wing tip (!), flew on dark moonless nights (!!), and took a series timed still exposures from the center of the circle on the same piece of film (!!!). The result was a "computerized" looking shot tracing the shape of the loop as a series of white dots. As I recall, he claimed to have made his loops much rounder using this technique.

Oddly, no one that I know of followed up on that great idea. With today's camcorders and mini lights, it would be a lead-pipe cinch!

It doesn't take much imagination to picture a "Fun-Fly" event called "Midnight Stunt" using human judges. Even better, we could even have an event called "e-mail Midnight Stunt" where flyers living miles apart could submit tapes for judging, and then . . .

Larry Fulwider

If you watch your own flying carefully and use a voice recorder to mark errors as you do them, you could catch all the errors in that cloverleaf in real time. Especially if the sky is partly cloudy and the clouds aren't moving fast. Then take the video, as Keith did, run it to a screen and use a marking pen to follow the plane(use clear drafting Mylar over an LCD screen to eliminate all the parallax you get with a standard TV set). Watch/listen to the whole thing with your coach and see how you did.

You can check how much distortion the camera is introducing by taking pictures of multi-story buildings from the appropriate distances and angles. From the little I've seen you get much more distortion by biasing the maneuvers just a few degrees off center than you get from the camera.

The camera may not do a perfect job on the exact shapes, but neither does the human eye. The camera does a great job of catching all the errors, and you can really see tracking and intersection errors well.

There should be a way to apply the "Puck trail" effect that Fox used for a while on hockey broadcasts---

Curt

I'll try to stay focused on the flying, not the camera.

Larry Fulwider


http://www.clstunt.com/htdocs/dc/user_files/22168.html

[photo not recovered: html.gif]Attachment #1, (html file)

I have probably logged more self judging camera time than most. I would estimate in the hundreds of hours. Some of what is posted is accurate and some is not. First let me state that it is very helpful and will get you 90% of the information you would get from a coach. The problem I had with coaches was communication or to be more accurate mis-communication. Sometimes the words we use to describe something is not what the person you are talking to hears. The camera does not mis-communicate.

A wide angle lens is needed. You can not get good data from as far back as the camera needs to be without one. The larger the lens camera you can get the closer you can be to the circle. The newer cameras are going to smaller and smaller lenses and this may be difficult to find but it is worth it. The cheaper, larger cameras seem to have larger lenses.
One of my cameras is smaller than the other and with the same wide angle lens it has to be 20 to 25 feet further back from the circle.

There are several things that take a while to get to know about filming your flights and this will waste some of you practice time. There are things that you will pick up on right away and others will take a while. Flying into the sun for one. You will not get much useful tape in this situation but you will get some.
With the wide angle lens and the largest lens camera I have I can put it on a tri-pod at the same place the judges would be standing. If I want the clearest picture of the lower maneuvers I set it to miss the tops of the verticals. You will find your own system before long based on what you are working on.
The camera will tell you most of what you need to know to get to the higher levels of competition. Intersections, tops, sides, shapes, etc… Just as the judges would see them. I also built some PVC poles and painted them dayglow orange as markers. I would place them (stakes in the ground) at the proper 45° and 90° angles. This would give me the proper maneuver size width. I had three poles. Center pole was for intersections. One of the things you will notice and have to get used to is not focusing on the poles. They are reference only and will let you know when you miss. I used these to let me know if I was flying too big or small or missing intersections. You can practice flying on the poles for a while to get your reference and feel for the size of the maneuvers but soon as you do you need to move on. The poles become the focal point and the rest of the maneuver suffers.

Learn how to set the focus on infinite (landscape). If not the camera in auto will search for something to focus on and will go in and out of focus. This is the worst on a clear day when the camera can not find anything to focus on in auto. Clouds help the focus but use the infinite and the problem goes away. When looking into the sun use the setting for this. Can’t think of the nomenclature right now but there is a setting for looking into the sun.
Early on I found that there were so many mistakes and errors in my pattern that I had to focus on just a few at a time. I would watch the videos and write down 5-6 to work on and this would be the focus of my next session. I would not move on till I got these fixed.
The main focus for me was to not get great video but video I could use to coach myself. The plane does not have to be clear for most of this but you need to see the tracking.
Once I had two cameras I could set one up at 90° to see the 45° elevation. Again the wide angle was a help but for this one you can look at the geometry of the ground, pilot, plane and angle of the lines relative to these elements.
You will find a lot of useful information videoing your flights. When watching your videos you can grease pencil (or dry eraser pen) them on the TV screen in slow motion to see what it really looks like.
The point is that you can work on the technical’s of the maneuvers and see in fact what your doing. Many times I would argue with my coach because I could not or would not see what he was telling me in my minds eye. I could not argue with the Video! What I got was something that I could see in my mind and correct. The next time I would fly I could see what the camera was showing me when before I could not.
I agree with some of what has been said in this thread that you need a coach. The camera is a coach and will get you 90% there and the human eye can get you the finer points, when you are ready.
RO

RO --

Hmm! I don't have the camcorder in my hands yet. My son's camcorder has the same optics as mine, so I'll do some tests and a little trig. Also, some questions from the other posts made me think it was "homework" time.

I know I have 45 degrees field of view with no zoom and with the standard (not wide angle) lens. I also know 4:3 is as good as it gets -- the 16:9 just clips the top and bottom of the image without widening the image, according to the review I read.

I did end up with more camcorder than I need, not because of the models, but for other (family) reasons. I don't think that gives ME any benefit that I know of.

Thanks, I'll post test results and calcs later.
(Just found out you have to turn off the "smilies" to type ratios with a colon in them!)

Larry Fulwider