No-one likes general adverts, and ours hadn't been updated for ages, so we're having a clear-out and a change round to make the new ones useful to you. These new adverts bring in a small amount to help pay for the board and keep it free for you to use, so please do use them whenever you can, Let our links help you find great books on glass or a new piece for your collection. Thank you for supporting the Board.

Author Topic: What causes this effect on this Monart bowl ?  (Read 621 times)

0 Members and 1 Guest are viewing this topic.

Offline Gary

  • Members
  • **
  • Posts: 728
  • Gender: Male
What causes this effect on this Monart bowl ?
« on: January 24, 2015, 11:49:59 AM »
I was hoping someone could explain what causes this effect. The first image is taken with the the sun/daylight behind the bowl, which show a blue colour, and goes all round the top of the bowl. The second image is taken with the sun/daylight in front of the bowl, and there is no sign of any blue. These two images were taken with a macro lens.
The third image is a top view of this small bowl (9.5cm wide).
Gary

Support the Glass Message Board by finding a book via book-seek.com


Offline chopin-liszt

  • Members
  • **
  • Posts: 14462
    • Scotland, Europe.
Re: What causes this effect on this Monart bowl ?
« Reply #1 on: January 24, 2015, 12:49:25 PM »
This is one of the joys of what glass can do with colour, Gary. It's the difference between reflected and refracted light. There is no blue when the light is reflected from the surface of the glass, but when light is coming through the glass, which contains colours, those colours will stop certain wavelenghts of light coming through - so what you see is what is left over from the spectrum of the rainbow - blue light gets through, (all other colours are stopped) so that is what you see.

There can be an interesting effect in some bits of Mdina, which have a frothy yellow background with teal blue strapping on top. When light comes through these pieces, the colour you see from the addition of blue and yellow is purple.
When you mix paint, you get green from blue and yellow.
Cheers, Sue M. (she/her)

‘For every problem there is a solution: neat, plausible and wrong’. H.L.Mencken

Support the Glass Message Board by finding glass through glass-seek.com


Offline Paul S.

  • Members
  • **
  • Posts: 9938
  • Gender: Male
Re: What causes this effect on this Monart bowl ?
« Reply #2 on: January 25, 2015, 09:35:52 AM »
hello Sue..........      can we use the word transmitted as an equal substitute for refracted.........  or have I been getting it wrong all these years :)

Support the Glass Message Board by finding a book via book-seek.com


Offline chopin-liszt

  • Members
  • **
  • Posts: 14462
    • Scotland, Europe.
Re: What causes this effect on this Monart bowl ?
« Reply #3 on: January 25, 2015, 02:02:46 PM »
 ???

probably...
(I'm confuddled now.)

I mean light coming thoguh the glass, which yes, is transmitted. But the light gets refracted by the colours inside it, so it doesn't ALL get transmitted. Some wavelengths are held back.
Cheers, Sue M. (she/her)

‘For every problem there is a solution: neat, plausible and wrong’. H.L.Mencken

Support the Glass Message Board by finding glass through glass-seek.com


Offline Paul S.

  • Members
  • **
  • Posts: 9938
  • Gender: Male
Re: What causes this effect on this Monart bowl ?
« Reply #4 on: January 25, 2015, 03:53:41 PM »
I've always thought of refraction as the business of how light can alter the position of how we see an object, when there's something like water or glass in the way -  similar to when we view the pencil in a glass of water, and it appears not to line up.       But you're right of course about light, when coming from behind something, produces colour variation and all the other clever techie bits etc. you mention.
Would you mind awfully though if I stick to using the word transmitted as the opposite of reflected - and you won't be cross :-* ;)  ;)

Support the Glass Message Board by finding a book via book-seek.com


Offline chopin-liszt

  • Members
  • **
  • Posts: 14462
    • Scotland, Europe.
Re: What causes this effect on this Monart bowl ?
« Reply #5 on: January 25, 2015, 04:13:45 PM »
Not at all, Paul. I'm doubting myself anyway. ;D
Cheers, Sue M. (she/her)

‘For every problem there is a solution: neat, plausible and wrong’. H.L.Mencken

Support the Glass Message Board by finding glass through glass-seek.com


Offline flying free

  • Members
  • **
  • Posts: 12693
    • UK
Re: What causes this effect on this Monart bowl ?
« Reply #6 on: January 25, 2015, 08:51:11 PM »
Nice description of both refracted and transmitted here on the Physics Classroom site

http://www.physicsclassroom.com/class/refrn/Lesson-1/The-Cause-of-Refraction
m

Support the Glass Message Board by finding a book via book-seek.com


Offline misha

  • Members
  • **
  • Posts: 206
  • Gender: Male
    • In the Hills of Melbourne - Australia
So it goes.

Support the Glass Message Board by finding glass through glass-seek.com


 

SMF spam blocked by CleanTalk
Visit the Glass Encyclopedia
link to glass encyclopedia
Visit the Online Glass Museum
link to glass museum


This website is provided by Angela Bowey, PO Box 113, Paihia 0247, New Zealand