OUCH, my brain hurts!!Math not my strong suit. I'll just have to download the
chart & trust the science & numbers.
Thanks for the infoPaul
-----Original Message-----
From: Bartsch, DIRK-UWE <dbartsch@xxxxxxxxxxxxxxx>
To: optimal@xxxxxxxxxxxxx <optimal@xxxxxxxxxxxxx>
Sent: Thu, Jun 24, 2021 8:23 pm
Subject: [optimal] Re: Neutral density filter
#yiv6337977278 P {margin-top:0;margin-bottom:0;}Here is another website that
explains the difference between the photography term ND2, ND4, ND8, ND16 and the
optical density term 2.0 OD ND filter, which is different than a ND2 filter.
As Ben pointed out correctly, a ND2 filter will cut the light in half. It also
has an optical density of 0.3. So to confuse things, a ND2 filter is the same
as a ND filter with OD of 0.3.
https://shuttermuse.com/neutral-density-filter-numbers-names/
| | Understanding Neutral Density Filter Names and NumbersAs a photographer
who flunked out of engineering school, the main thing I want to know is what ND
filter do I need to achieve a certain f stop/shutter speed/ISO combination and
by your excellent table I see a neat way to turn optical density numbers into f
stop reduction numbers.shuttermuse.com |
So, if you have a ND filter, check if it is the photography filter factor or
the optical density.
Dirk-Uwe
From: optimal-bounce@xxxxxxxxxxxxx <optimal-bounce@xxxxxxxxxxxxx> on behalf of
Ben Serar <serarphoto@xxxxxxxxx>
Sent: Thursday, June 24, 2021 3:01 PM
To: optimal@xxxxxxxxxxxxx <optimal@xxxxxxxxxxxxx>
Subject: [optimal] Re: Neutral density filter Hi,
A regular 2 ND filter will cut the light in half.Ben
On Thu, Jun 24, 2021 at 2:25 PM Bartsch, DIRK-UWE <dbartsch@xxxxxxxxxxxxxxx>
wrote:
1% is the correct transmission for a 2.0 ND filter.
Here is a handy web reference from Edmund Optics
https://www.edmundoptics.com/knowledge-center/application-notes/optics/understanding-neutral-density-filters/
| | Understanding Neutral Density Filters | Edmund OpticsNeutral Density (ND)
filters are designed to reduce transmission evenly across a portion of a
specific spectrum. ND filters are typically defined by their Optical Density
(OD) which describes the amount of energy blocked by the filter. A high optical
density value indicates very low transmission, and low optical density
indicates high transmission (Equations 1 – 2).www.edmundoptics.com |
From:optimal-bounce@xxxxxxxxxxxxx <optimal-bounce@xxxxxxxxxxxxx> on behalf of
Laine <laine@xxxxxxxxxxxxxxxxxxxxx>
Sent: Thursday, June 24, 2021 2:16 PM
To: optimal@xxxxxxxxxxxxx <optimal@xxxxxxxxxxxxx>
Subject: [optimal] Re: Neutral density filter Are you asking what the
transmission % is? 1%
On Jun 24, 2021 4:09 PM, Kirsten G Locke <kglocke@xxxxxxxxxxxxxxxxxxxx> wrote:
2.0 ND means that it cuts light by 10^2 (or 100) times. Thanks,Kirsten Kirsten
Locke, CRA. OCT-C. RN. FOPSClinical Trials ManagerRetina Foundation of the
Southwest9600 N. Central Expressway, Suite 200Dallas, TX 75231P: 214.363.3911,
Press 0 and ask for meF: 214.363.4538E:
kglocke@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Website| Facebook|Instagram| LinkedIn|Twitter|YouTube From:
optimal-bounce@xxxxxxxxxxxxx [mailto:optimal-bounce@xxxxxxxxxxxxx]On Behalf Of ;
Eric Kegley
Sent: Thursday, June 24, 2021 3:40 PM
To: optimal@xxxxxxxxxxxxx
Subject: [optimal] Neutral density filter Hello all, This is the second time in
a week that I am having to ask for help. What is optical density of a 2.0 log
unit neutral density filter? Thank You, Eric Kegley, CRA, OCT-C, FOPS,
COTDirector of Imaging Retina Consultants of Texas Research Centers4460
Bissonnet St, Ste 200Bellaire, TX 77401O: 713.524.3434 ext. 4831D:
713.394-7531C: 281.236.0215F: 713.795.4552RetinaConsultantsTexas.com Notice:
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