Olympus UK E-System User Group
Olympus UK E-System User Group

Join our unique resource for Olympus Four Thirds E-System DSLR and Pen and OM-D Micro Four Thirds photographers. Show your images via our free e-group photo gallery. Please read the e-group.uk.net forum terms and conditions before posting for the first time. Above all, welcome!


Go Back   Olympus UK E-System User Group > Cameras, lenses and system accessories > Lens focus > Converters, adapters and extension tubes

Converters, adapters and extension tubes All those lens accessories that get in between the lens and the camera.

Reply
 
Thread Tools Display Modes
  #16  
Old 27th June 2018
Ricoh Ricoh is offline
Full member
 
Join Date: Apr 2014
Location: Lancashire
Posts: 5,792
Thanks: 592
Thanked 421 Times in 373 Posts
Likes: 787
Liked 1,919 Times in 1,143 Posts
Re: Polarising Filter

Quote:
Originally Posted by Ian View Post
I think we're differing over semantics - the reason I'm being obstinate is that I feel there could otherwise be confusion.

Ian
My error. I was referring, from memory, to a physics experiment from way back as a student. For photography one sheet of polariser is all that is required, rotating about the axis.
For what it's worth, I have a two element polariser purchased in the 70's. Inscribed on it are the words 'Japan' and 'Polariser'. I'm sure it does polarise but act more like an ND. I will take it for a field test in due course.
__________________
Steve

on flickr
Reply With Quote
The Following User Liked This Post:
Ian (27th June 2018)
  #17  
Old 27th June 2018
Ian's Avatar
Ian Ian is offline
Administrator
 
Join Date: Jul 2007
Location: Hemel Hempstead, Hertfordshire, UK
Posts: 11,341
Thanks: 412
Thanked 2,423 Times in 1,220 Posts
Likes: 816
Liked 1,627 Times in 723 Posts
Re: Polarising Filter

Quote:
Originally Posted by Ricoh View Post
My error. I was referring, from memory, to a physics experiment from way back as a student. For photography one sheet of polariser is all that is required, rotating about the axis.
For what it's worth, I have a two element polariser purchased in the 70's. Inscribed on it are the words 'Japan' and 'Polariser'. I'm sure it does polarise but act more like an ND. I will take it for a field test in due course.
Yes, dual polariser variable NDs can be purchased widely today. I have a cheap Phot-R one bought on eBay for around a tenner which I am intending to experiment with as a 'big stopper' alternative and for managing video shutter speed (keeping it within the desired 180 rule range).

Ian
__________________
Founder and editor of:
Olympus UK E-System User Group (http://e-group.uk.net)
Four Thirds User (http://fourthirds-user.com)
Digital Photography Now (http://dpnow.com)
Olympus camera, lens, and accessory hire (http://e-group.uk.net/hire)

Twitter: www.twitter.com/ian_burley
Flickr: www.flickr.com/photos/dpnow/
Pinterest: www.pinterest.com/ianburley/
NEW: My personal BLOG ianburley.com
Reply With Quote
  #18  
Old 27th June 2018
Petrochemist Petrochemist is offline
Full member
 
Join Date: Apr 2015
Location: N Essex
Posts: 713
Thanks: 36
Thanked 79 Times in 72 Posts
Likes: 207
Liked 118 Times in 86 Posts
Re: Polarising Filter

Quote:
Originally Posted by MikeOxon View Post
The 'same' cannot be achieved in post-processing but in many cases it's effects can be simulated.

One use of a PL filter is to reduce reflections from the surface of water, to help in seeing what's underneath. That's why anglers use polarising sunglasses. If you like photographing fish, there's no substitute.

Another use is to increase contrast in skies and that can usually be simulated fairly well, by increasing saturation of the sky area in post-processing.

There are other specialist applications, such as showing stress lines in plastics, for which there is no substitute.

I do have some PL filters but confess I rarely use them.

The 'double' types, with two components, are intended as variable neutral-density filters, which can occasionally be useful.


I always find it odd that photographers concentrate on the reducing reflections aspect of polarisers - I often find using a polarizer to increase the reflection works well too. Boosting reflections like this (non Olympus example https://flic.kr/p/8SQQSX) & the plastic stress patterns (https://flic.kr/p/26brVCn using a laptop screen for lighting) are far and away my most successful uses of polarisers.


Double polarisers for ND filters can work well but I've had a few occasions where the results were appalling I suspect the subject had an unusually high amount of polarization, but the image came out with a very strong (+) cross. Much worse than the typical X seen in skies with them. Fortunately they work pretty well for IR photography most of the time controllably reducing the visible portion seen with my full spectrum camera, but having minimal effect on the NIR.
__________________
Mike
Compulsive photographic Dabbler.
Flickr
Reply With Quote
The Following User Says Thank You to Petrochemist For This Useful Post:
MJ224 (27th June 2018)
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
HELP! Linear polarising filter help! DJMC Accessory talk 3 19th June 2017 04:14 PM
Polarising filter littletonlad Olympus OM-D E-M1 15 12th July 2014 04:36 PM
can anyone recommed a polarising filter for the E-520 Sabroc Olympus E-520 4 10th October 2010 11:34 AM
Polarising filter - and a tripod? Ellie Accessory talk 13 28th April 2009 07:30 AM
Polarising filter PeterD Telephoto 4 13th November 2008 10:16 PM


All times are GMT. The time now is 03:48 PM.


The Write Technology Ltd, 2007-2019, All rights reservedAd Management plugin by RedTyger