Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-30-2013, 10:18 AM - 1 Like   #1
Site Supporter
JimJohnson's Avatar

Join Date: Jan 2012
Location: Lake Superior - Michigan
Photos: Gallery
Posts: 2,249
Spring at last!

Both of the images below were shot with my K-r and a Pentax F35-70, auto-focus, aperture priority (f/4.5) to force a high shutter speed to capture the drips of water falling from the icicles hanging from our roof.

The images were taken from my home-office window through two 100+ year-old panes of plate glass that haven't been cleaned for six months. Distortion free glass for a residence wasn't common in the early 1900's, and trust me, both panes have plenty of distortion.

Attached Images
 
View Picture EXIF
PENTAX K-r  Photo 
03-30-2013, 10:37 AM   #2
Veteran Member
Docrwm's Avatar

Join Date: Sep 2010
Location: Somewhere in the Southern US
Photos: Gallery | Albums
Posts: 11,275
Very nice. Glass is a semi-solid and the glass was reasonably distortion free 100 years ago, but over time it has flowed downward due to the unrelenting pull of gravity and its nature.
03-30-2013, 03:43 PM   #3
Site Supporter




Join Date: Oct 2012
Location: Edina, MN
Posts: 248
QuoteOriginally posted by Docrwm Quote
Very nice. Glass is a semi-solid and the glass was reasonably distortion free 100 years ago, but over time it has flowed downward due to the unrelenting pull of gravity and its nature.
I think that's what's also happened to my physique - maybe it's not 100 years, but the unrelenting pull of gravity has had its effect.

;-)

By the way, nice pics - brings back memories of when we lived in a house here in Minnesota - the joys of icicles and ice dams. Now we live in an apartment, so I don't have to worry about water backing up into the roof.
03-30-2013, 06:44 PM - 1 Like   #4
Site Supporter
JimJohnson's Avatar

Join Date: Jan 2012
Location: Lake Superior - Michigan
Photos: Gallery
Posts: 2,249
Original Poster
QuoteOriginally posted by Docrwm Quote
Very nice. Glass is a semi-solid and the glass was reasonably distortion free 100 years ago, but over time it has flowed downward due to the unrelenting pull of gravity and its nature.
Umm, yes glass is actually a liquid and it does flow in the direction of gravity - but most of the distortion in this house's original glass is due to the manufacturing techniques commonly used for residential glazing in the early 1900's rather than gravity. You can purchase new glass made using 100 year-old methods to replace the glass in historic structures. Such glass will have distortion similar to that in my home. If gravity worked that fast on glass, some of my antique cameras would be unusable. You can find examples of gravity distorted glass, but it has been in place much longer than the glass in my home.

But while we are on the topic, here is an experiment that has been in continuous operation on a high viscosity fluid since 1927: The Pitch Drop Experiment | School of Mathematics and Physics

04-01-2013, 10:42 AM   #5
Site Supporter
grhazelton's Avatar

Join Date: Jul 2007
Location: Jonesboro, GA
Photos: Albums
Posts: 1,826
QuoteOriginally posted by JimJohnson Quote
Umm, yes glass is actually a liquid and it does flow in the direction of gravity - but most of the distortion in this house's original glass is due to the manufacturing techniques commonly used for residential glazing in the early 1900's rather than gravity. You can purchase new glass made using 100 year-old methods to replace the glass in historic structures. Such glass will have distortion similar to that in my home. If gravity worked that fast on glass, some of my antique cameras would be unusable. You can find examples of gravity distorted glass, but it has been in place much longer than the glass in my home.

But while we are on the topic, here is an experiment that has been in continuous operation on a high viscosity fluid since 1927: The Pitch Drop Experiment | School of Mathematics and Physics
Interesting link! For whatever reason your link and the viscosity of glass brought to mind Prince Rupert's Drops. A strange bit of glass with a long tail. The head will withstand a hammer blow, but even slightly damage the tail and the whole thing shatters explosively! See this link: Prince Rupert's Drop - Wikipedia, the free encyclopedia
04-04-2013, 11:39 PM   #6
rfg
Senior Member




Join Date: Dec 2010
Location: Sydney
Posts: 137
QuoteOriginally posted by JimJohnson Quote
Umm, yes glass is actually a liquid and it does flow in the direction of gravity -
I thought so too until recently, but it appears to be an urban myth. See Is glass liquid or solid? for an interesting analysis of whether glass is solid or liquid & whether there is evidence that it flows.

The pitch drop experiment is pretty cool too - thanks for the link!
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, distortion, glass, images, k-r, kr, panes, pentax k-r
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Nature Waiting for spring-last of the winter leaves normhead Post Your Photos! 17 03-21-2013 06:56 AM
Macro Just flowers (spring at last!) juanraortiz Post Your Photos! 3 05-24-2010 07:44 AM
Nature Some flowers from last spring Heinrich Lohmann Post Your Photos! 6 10-08-2009 03:07 PM
At last, signs of spring c13_ Post Your Photos! 1 04-18-2008 02:16 PM
Last snow of 2007 Winter/Spring photo_mom Post Your Photos! 10 05-01-2007 04:09 AM



All times are GMT -7. The time now is 08:32 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top