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Chuck Spaulding August 7th, 2010 10:45 AM

Aerial Footage
 
Trying to figure out a cost effective wey to get aerial footage.

Stability was better than I thought it would be, certainly something I can Improve on, but the picture quality is marginal.

Canon 17-55 at f/16 IS off ISO100 Shutter 125. Anyone have any suggestions on how to make the footage a lot sharper?


Ralph Gereg August 7th, 2010 10:50 AM

That is pretty cool. I'd be intereseted to learna bit more about the plane that was used to shoot this sample. Was it taken from a manned or remote control plane?

Perrone Ford August 7th, 2010 11:14 AM

Interesting choice of lens....

Well, I wasn't there so I can only point out a few generic things.

1. Why was IS turned off? Seems like this is nearly an ideal case to have it on.

2. What vibration damping was done between the camera mount and the ultralight?

3. It looked almost as if there was focus creep. Infinity focus seemed to be off, but that could just be the vibration from the ultralight motor.

4. And the obvious to me... why use a zoom here and not a prime? Certainly there aren't going to be any re-framing needs in the shot.

5. A polarizer would have likely been a good choice here

6. Might want to shoot at F8 in the future. Most lenses are going to lose sharpness at F-Stops below that.


Anyway, that's just my thoughts.

Andy Wilkinson August 7th, 2010 11:18 AM

Ignore - double post somehow so this one removed!

Andy Wilkinson August 7th, 2010 11:21 AM

Regarding making the footage sharper...I think F16 is getting a bit high and you're starting to risk diffraction softening. If I remember correctly, the sweet spot for this lens (I have it for my 7D) is a lower - I would need to check some of the photography review sites but my guess is at F5.6 to F8 area, no higher than F11 will get the best out of the glass sharpness wise (within the depth of field set by focus ring). Also, why did you go for 125th second rather than (in the USA) 1/60th shutter speed, was that because of lack of a ND filter in bright conditions? ....oh I see it was at 24fps...

The footage looks pretty good/well damped from vibration otherwise, nice and smooth. Nice test!!!

Chris Soucy August 7th, 2010 11:04 PM

Hi Chuck............
 
try a wider Prime (already suggested), shoot wider, get lower.

Increase ISO to 200, stick at F8, don't shoot at 24 fps but 60i (heck, 60p if available), raise shutter to 250, it'll look a dream.

Depends on the look you're after, of course - you said "sharper".

The above will give you "sharper".


CS

Chuck Spaulding August 12th, 2010 11:14 AM

Thanks guys for the feedback.

I did use a polarizer but when I turned directly into the son it obviously becomes ineffective. Would the same be true of an ND filter? I have an ND filter I can use to get the f-stop into the range it should be.

The only prime [or non zoom] is an f/1.4 85mm without IS, for the conditions was too fast and narrow FOV. This was my first flight with the ultralight so I decided to keep IS off, I wanted to see how stable and what kind of vibration I would get without it. Actually I was pleasantly surprised how smooth it was.

Regarding the camera mount, I wrapped a piece of string around the base of the lens [where it connects to the camera], connected it to a bungee cord that was securely attached to the ultralight. I could raise and lower where I wanted the camera to hang as well as adjust the firmness of the bungee by adding knots in it. Then I just hand held the camera.

Andy, I was flying at about 40 mph, I thought there might be quite a bit of motion blur at that speed close to the ground so I decided to try a higher shutter speed to see it might be a bit sharper.

Chris, I shot this 30P then used CinemaTools to convert it to 24P so it reduced the playback by 20% which I like. The 7D does shoot 60P but only in 720 which I don't like, the moire and softness are exaggerated when it gets converted for a 1080 project. Here's an example of a 720P60 used in a 1080P24 timeline:


So as a result of this test, and for the next test, I'm going to use my Tamron 17-50 mm @ about 24 mm, with a variable ND to get an f-stop of f/5.6-f/8.0, a shutter of 1/60 with IS on.

Any other suggestions are always welcome.

Sorry, one more thing, Chris I can't use a wider prime because if I do I get my feet in the shot.


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