Hang time???

[lph]

OK, COTW with Micah got me thinking. (which is amazing in intself, as I am pretty sure I still have some Tequila and Sambuca in my system from saturday night. )

We have talked about the size of a cliff huck. Do you measure just the vertical, or from where the person took off to where they landed, etc....

In the COTW posted by ONS, Micah seems to hang in the air forever.

What about hangtime. Sort of like a punt in football, would that be a reasonable way to sort of decide how huge a huck is??

[Plakespear]

Considering that most ski fims are shot in slow motion, hang time is not a very good indication of the size of a cliff huck.

[DJSapp]

Yes, hangtime is a criticle part of the verticle height calc, alongside rate of verticle decent. Horizontal speed has nothing to do with time in the air on cliff hucks, but the rate of . If I remeber my phyics correctly:

Z=Zo + Vo*t + 1/2*g*t^2

Where
Z is verticle distance of huck
Zo is original height of huck (set=0 for simplicity)
Vo is rate of verticle decent
t is hangtime
g is acceleration due to gravity (use ~9.5 m/s, due to wind resistance from skis)

if Vo is close to zero, (i.e. skier starts from relative standstill), just drop that term for an approximate value. If he hits the huck with a good head of steam, calculate the verticle decent speed by getting his speed (radar gun or other means) and slope angle.

Edit: yeah, slow motion screws everything up, use the equation with caution.

[Buster Highmen]

you're neglecting the pucker factor.

[robokill1981]

Depends how you say it:

"Plakespear dropped that 20 footer"
or
"Plakespear went so fast he hucked 30 feet off that 20 footer"
or
"Plakespear dropped that 20 footer, but he had to pre-jump 5 feet above it to avoid some rocks"


Cliffs should only be measured by how big they are, but including how far you went off a cliff gives a good idea of how big you actually went.

[lph]

Originally posted by Plakespear
Considering that most ski fims are shot in slow motion, hang time is not a very good indication of the size of a cliff huck.

They are shot in slomotion? Or they are slowed down during editing? I think if you used the raw footage, you could do it.

[DJSapp]

Originally posted by lph
They are shot in slomotion? Or they are slowed down during editing? I think if you used the raw footage, you could do it.

That's an old movie trick. They'll shoot at a higher speed like 60 FPS, and then playback at 30 FPS, making 1 real sec = 2 sec on film. It's good for big explosions of models, i.e. blowing up death stars, USS Enterprise, etc.

[lemon boy]

actual films are done slow mo by using a higher rate of film (more frames/second) I believe.

huck equals the actual distance of the cliff, you can amplify it by all the qualifiers you want but 5 feet of rock showin is still 5 feet.

edit- therefore the COTW is a zero footer.

[hev]

you guys are right but the fact that the huck might shoot you up first would throw off your calculations. This however is a very low percentage of cliff hucks so time would actually be an acurate way to calculate height. you also need to add a coeffecient-of-fart-bag due to wind resistance

[pollard]

hang time is what makes me remember a huck.

[UTdave]

Originally posted by lemon boy
actual films are done slow mo by using a higher rate of film (more frames/second) I believe.

huck equals the actual distance of the cliff, you can amplify it by all the qualifiers you want but 5 feet of rock showin is still 5 feet.

edit- therefore the COTW is a zero footer.

[GT40]

I was watching them film pros one day and they were shooting film at 120fps for the slo-mo parts.

Easy way to burn lots of film and $.

[Plakespear]

Yeah, shooting at 120fps is expen$ive, but that's the only way to do it right. You could slow it down in post, but it wouldn't look anywhere near as good. This is a big factor why it costs so much to shoot a ski movie on film.

[hev]

i actually just tried watching a ski movie in 2x mode dvd ffw...looks cool. almost ever shot is in normal speed.

[Telephil]

It's funny this topic seems to come up every year on every board I've been on. I'm pretty much in agreement with LB though, 5 feet of rock is 5 feet. You can however, go huge or small, but 5 is 5.

[iceman]

Originally posted by Telephil
It's funny this topic seems to come up every year on every board I've been on.

Who knew Martha Stewart and Rosie were into hucking?

[phUnk]

Dumbest topic ever.

[iceman]

Originally posted by phUnk
Dumbest topic ever.

Ya think?

Lots of dumb topics over the years.

[phUnk]

Originally posted by iceman
Ya think?

Lots of dumb topics over the years.

Ever.

[truth]

Whatever assman.

[lph]

Originally posted by phUnk
Dumbest topic ever.

It is a dumb topic, I will grant you that. But the dumbest? I don't think it is even in the ball park.

Over the years, you have made that claim repeatedly. How many "Dumbest topic ever" topics can there really be?


Two basketball players have the same vertical leap, however, one seems to hang in the air forever, the other seems to leave and return to ground quickly. Which is more awe-inspiring? BTW, it is not an optical illusion, as pointed out by DJ, there are alot of variables in hang time.

[Jumper Bones]

*simpson's comic-book guy voice*

"wost...movie....ever"

[road trip]

Originally posted by DJSapp
It's good for big explosions of models, i.e. blowing up death stars, USS Enterprise, etc.