Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
09-29-2020, 01:55 PM - 3 Likes   #1
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 5,180
Polarizing Filters: Bell's Theorem

Some polarizing filter cerebral fun for your Tuesday!


Mind blown at around 1:00 !

09-30-2020, 05:38 AM - 1 Like   #2
Senior Member




Join Date: Jan 2015
Posts: 228
QuoteOriginally posted by FozzFoster Quote
Mind blown at around 1:00 !
That's what you get when looking at quantum physics.
It's the universe telling you that's the place you should not look .
Or a matrix bug ...
09-30-2020, 07:53 AM - 1 Like   #3
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 17,340
I love this. I hate this. I am more than moderately pleased by this. Lol.
09-30-2020, 09:30 AM - 1 Like   #4
Pentaxian
normhead's Avatar

Join Date: Jun 2007
Location: Near Algonquin Park
Photos: Gallery | Albums
Posts: 36,221
Way too much fun for a Wednesday.

09-30-2020, 11:18 AM - 1 Like   #5
Pentaxian
Ontarian50's Avatar

Join Date: Mar 2015
Posts: 516
Well, I took three polarizers and tried this experiment on my light table.

Can't figure out what I'm doing wrong, but I can't get it to work.

Once the first two are fully polarized, the third polarizer doesn't make anything lighter.

So ..... ?
09-30-2020, 11:21 AM   #6
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 5,180
Original Poster
QuoteOriginally posted by Ontarian50 Quote
So ..... ?
I really don't know, but is it to do with the difference between linear and circular polarizers?
09-30-2020, 01:13 PM - 1 Like   #7
Site Supporter
Site Supporter




Join Date: Dec 2015
Location: Goldsboro North Carolina
Photos: Gallery | Albums
Posts: 1,729
QuoteOriginally posted by FozzFoster Quote
is it to do with the difference between linear and circular polarizers?
That occurred to me too, though I don't claim to be well versed in the difference between the two.

Who knew you could look through polarizing filters and see Schrodinger's cat! Love this.
09-30-2020, 05:11 PM - 1 Like   #8
Journeyman Cat Wrangler
Loyal Site Supporter
SSGGeezer's Avatar

Join Date: Jun 2017
Location: Maine, U.S.
Photos: Gallery | Albums
Posts: 4,793
Thanks, now my brain is melting! Very cool video. I think I need to re-watch it about 3 or 10 more times.

10-01-2020, 07:49 AM - 1 Like   #9
Pentaxian
Ontarian50's Avatar

Join Date: Mar 2015
Posts: 516
I think I'm ready to call hoax on this. The video looks convincing, but I can't replicate what they're doing on my light table with three regular linear polarizers. Circular polarizers don't work at all for cancelling each other out.

And it makes some sense. Universities have spent big money firing single photons through slits in dark rooms to explore the quantum nature of light. If all they had to do was play with three ordinary polarizers to see quantum entanglement with the naked eye ... well, why wouldn't they?

Also, how have we not heard of this before? If all we had to do was stack three polarizers in front of our lenses - the front one at zero degrees, the middle one at ninety degrees, and the rear one at forty-five degrees, we could all have been making magical photos with quantum entangled light. I can see the gallery brochure now ... "Quantum Landscapes".

How would our pet photography look, or the leaves on our backyard trees look (favourite Pentax lens test targets) if our sensors were recording only quantum filtered light?

Sorry, but I just can't make it work. I put it out there to other Pentaxians to "peer review" the video and see if they can replicate the phenomenon. Is there something extra special about their setup? The polarizers are touted to be ordinary camera ones (again, circular polarizers cannot work in this experiment - but I tried them anyway). Is there something special about their light source? Or their camera?

But again, I come back the realization that I've been mucking about with polarizers for years, and I think I might have noticed if a third one cancelled out the effects of two others.

If anyone can enlighten me (or their polarizers) without video special effects, please let me know.
10-01-2020, 08:20 AM   #10
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 5,180
Original Poster
QuoteOriginally posted by Ontarian50 Quote
please let me know.
I just replicated the results using three pairs of polarized sunglasses and using my computer screen as a light source.

---------- Post added 10-01-20 at 09:30 AM ----------

QuoteOriginally posted by Ontarian50 Quote
Also, how have we not heard of this before?
Now I'm thinking: why haven't I used two polarizers as a make-shift ND variable fitler!
Seems to me that'd work... haha
10-01-2020, 08:33 AM - 1 Like   #11
Pentaxian
Ontarian50's Avatar

Join Date: Mar 2015
Posts: 516
Aha! I think I have figured it out. With a bit more internet research, it turns out the third polarizer doesn't come after the first two, but must be inserted between them. I didn't get that from the initial video - which I think to most of us made it look like the last polarizer undid the cancelling actions of the first two.

So, to be clear, polarizers A and B are set to cancel each other out, then polarizer C is inserted between them at a forty-five degree angle and light is passed through.

However, this does seem a bit underwhelming - and not the "mind blowing" effect I thought I was seeing in the video.

Logically, polarizer A and C are at forty-five degrees, and so you get a half polarizing effect. Polarizer B at the back is another forty-five degrees rotated (at 90 to polarizer A) and you lose more light, but not all.

So, half of a half, is a quarter, and that looks like about what you get after the third polarizer.

I know, I get it. Theoretically, the rear polarizer should cancel out the front one entirely, but doesn't when there's another one in between. Still, it's a lot less magical than how it is presented in the video.

My gallery opening for landscapes taken with quantum entangled light has been cancelled.

---------- Post added 10-01-20 at 11:35 AM ----------

QuoteOriginally posted by FozzFoster Quote
Now I'm thinking: why haven't I used two polarizers as a make-shift ND variable fitler!
Seems to me that'd work... haha
Actually, that's all a variable ND filter is. The trick is putting them into one thin frame so they don't vignette a wide angle lens.
10-01-2020, 08:42 AM   #12
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 5,180
Original Poster
QuoteOriginally posted by Ontarian50 Quote
However, this does seem a bit underwhelming
I agree that the actual results are underwhelming to what your initial assumptions were, but the reality is still mind boggling and far from logical.

Filter A and C are perpendicular - zero light passes.
Filter B is added between them, and you get some light passing through.
Logically, you'd think that filter B would stop even more light from passing through, if that were possible.

The experiment makes it seem that filter B is 'adding' light.

and not only that, but apparently mathematically, more light than what would be expected gets through.

It's a double whammy of mind bogglin'

---------- Post added 10-01-20 at 09:46 AM ----------

QuoteOriginally posted by Ontarian50 Quote
Actually, that's all a variable ND filter is
No kiddin, I didn't know that a variable ND filter, in addition, polarized your images!
Thanks for sharing that haha

Last edited by FozzFoster; 10-01-2020 at 08:55 AM. Reason: corrections...
10-01-2020, 02:31 PM - 2 Likes   #13
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 17,340
You need to watch it again carefully.

A @ 0 degrees
B @ 22.5 degrees
C @ 90 degrees

A+C = 50% transmission
A+B = 85% transmission
(Odd itself as prediction would suggest 75% in a classical model)
A+B+C = 70%

Adding B bumped up the light passing C from 50% to 70%.

At this point I figured that the alignment in space as it flowed through was bending some of the waves into compliance and more if the were able to pass C due to that. But then they used them separately but with entangled particles and the results were unchanged. That's when my brain melted. Mind you I read physics for fun. I'm still a quantum sceptic not suggesting it doesn't work but suggesting the explanations are like a bunch of blind men describing an elephant. But it is very reliable in prediction and it is heavily studied and proven. I still rebel a bit in my head against the universe this implies.
10-01-2020, 02:47 PM   #14
Custom User Title
Loyal Site Supporter
FozzFoster's Avatar

Join Date: Jan 2016
Location: Alberta
Photos: Albums
Posts: 5,180
Original Poster
QuoteOriginally posted by UncleVanya Quote
A+C = 50% transmission
A+B = 85% transmission
(Odd itself as prediction would suggest 75% in a classical model)
A+B+C = 70%
A= 50% polarized light transmission
A+C= 0% polarized transmission
A+B+C = more light than expected
10-01-2020, 03:09 PM - 1 Like   #15
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 17,340
QuoteOriginally posted by FozzFoster Quote
A= 50% polarized light transmission
A+C= 0% polarized transmission
A+B+C = more light than expected
See time index 4:47
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!
angle, degrees, effect, filter, half, light, mind, photography, polarizer, polarizers, third, video
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Polarizing filters and the D FA* 85/1.4 Wheatfield Pentax SLR Lens Discussion 15 08-22-2020 11:33 AM
DA*16-50mm and polarizing filters ChristianRock Pentax SLR Lens Discussion 13 07-16-2020 06:10 AM
MeFoto polarizing filters $4 to $5 at Adorama onlineflyer Pentax Price Watch 17 01-30-2019 06:52 PM
For Sale - Sold: Kenko Pro1D Polarizing & B+W Graduated ND Filters (67mm & 77mm) sft Sold Items 3 05-06-2012 04:14 PM
For Sale - Sold: Sigma 10-20mm F4.0-5.6, 77mm UV and Polarizing filters (CONUS) grainbelt Sold Items 2 09-30-2010 12:21 AM



All times are GMT -7. The time now is 03:28 PM. | 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