Visit the Cellar!

The Cellar Image of the Day is just a section of a larger web community: bright folks talking about everything. The Cellar is the original coffeeshop with no coffee and no shop. Founded in 1990, The Cellar is one of the oldest communities on the net. Join us at the table if you like!

 
What's IotD?

The interesting, amazing, or mind-boggling images of our days.

IotD Stuff

ARCHIVES - over 13 years of IotD!
About IotD
RSS2
XML

Permalink Latest Image

June 24th, 2017: North American Food

Recent Images

June 23rd, 2017: Moist Towelettes
June 22nd, 2017: Doodling
June 21st, 2017: Octopus’s Garden
June 20th, 2017: Money Slang
June 19th, 2017: French Phony
June 18th, 2017: A B C… J K L… U V War…
June 16th, 2017: Hōkūleʻa

The CELLAR Tip Mug
Some folks who have noticed IotD

Neatorama
Worth1000
Mental Floss
Boing Boing
Switched
W3streams
GruntDoc's Blog
No Quarters
Making Light
darrenbarefoot.com
GromBlog
b3ta
Church of the Whale Penis
UniqueDaily.com
Sailor Coruscant
Projectionist

Link to us and we will try to find you after many months!

Common image haunts

Astro Pic of the Day
Earth Sci Pic of the Day
We Make Money Not Art
Spluch
ochevidec.net
Strange New Products
Geisha Asobi Blog
Cute animals blog (in Russian)
20minutos.es
Yahoo Most Emailed

Please avoid copyrighted images (or get permission) when posting!

Advertising

Philadelphia Pawn Shop
The best real estate agent in Montgomery County
The best T.38 Fax provider
Epps Beverages and Beer, Limerick, PA
Sal's Pizza, Elkins Park
Burholme Auto Body, Philadelphia
Coles Tobacco, Pottstown
ERM Auto Service, Glenside
Glenside Collision
Moorehead Catering, Trappe
Salon 153, Bala
Dominicks Auto Body, Phoenixville

   Undertoad  Wednesday Dec 5 10:58 AM

12/5: Tennis ball being struck



From a gallery of high-speed photography, this is what actually happens when a tennis ball is struck: the ball actually compresses to about half its usual size.

To get the image, a flash unit had to be set up with an audio trigger so the photo could be shot via the sound of the racquet hitting the ball. It would seem that setting up the trigger is the key to this sort of high speed photography.



jet_silver  Wednesday Dec 5 11:20 AM

A lot of these triggering problems were solved by Harold Edgerton, the E in EG&G for you physical sciences wonks. He developed this kind of stroboscopic photography, among other things.

There is a WGBH portrait of Edgerton that was shown periodically on PBS when I was still watching TV; it may still be making the rounds. Edgerton comes off as very charming and interested in learning how the triggers should work. The 'bat in flight' portrait where the bat is catching a worm is profiled in that show.

The transcript is at http://net.unl.edu/artsFeat/edgertontrans.html



IndyTone  Wednesday Dec 5 02:37 PM

Re: 12/5: Tennis ball being struck

Quote:
Originally posted by Undertoad


From a gallery of high-speed photography...
Any chance you can up the URL of this gallery? It would be keen.


Undertoad  Wednesday Dec 5 02:45 PM

Well that would preclude me using another one of the images tomorrow but no biggie:

http://www.pacsci.org/public/educati...nt_photos.html



russotto  Thursday Dec 6 03:18 PM

Re: 12/5: Tennis ball being struck

Quote:
Originally posted by Undertoad
To get the image, a flash unit had to be set up with an audio trigger so the photo could be shot via the sound of the racquet hitting the ball. It would seem that setting up the trigger is the key to this sort of high speed photography.
The other thing is that you need to do it in darkness. Mechanical clockwork shutters aren't fast enough to capture this sort of thing. So you leave the shutter open and use the flash to get the shot.

An electronic (e.g. LCD) shutter might work nowadays (or might not), but obviously didn't exist when Edgerton worded on this stuff. I believe he invented some of the flash tubes used to do it, also.


cgifool  Friday Dec 7 11:06 PM

Edgerton book

If you're interested in this stuff, I recommend the book Electronic Flash, Strobe by Harold Edgerton. I got mine for just a couple dollars in the cutout bin at Barnes & Noble. He talks all about the circuits and triggering and other fun stuff. If you dont mind paying more, Mit Press has it too.

http://mitpress.mit.edu/catalog/item...ype=2&tid=4740



Your reply here?

The Cellar Image of the Day is just a section of a larger web community: a bunch of interesting folks talking about everything. Add your two cents to IotD by joining the Cellar.