Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
07-01-2013, 04:42 AM   #1
New Member

Join Date: Jun 2013
Photos: Albums
Posts: 7
ND filters

i am wanting to purchase an ND filter but when looking for one i noticed there are different types or different shades? is this true or am i just being a complete noob!?

07-01-2013, 04:51 AM   #2
Site Supporter
Site Supporter
mattt's Avatar

Join Date: Feb 2011
Location: Niagara
Photos: Gallery | Albums
Posts: 2,934
ND filters come with different "slowing power". Usually in steps of 1/2 reduction in light. I keep an ND8 (3 stop) in my bag at all times. I also have a 9 stop filter for nice long exposures.
07-01-2013, 04:51 AM   #3
Veteran Member
dmort's Avatar

Join Date: Apr 2011
Location: Bronx, NY
Photos: Gallery | Albums
Posts: 415
ND filters have numbers that correspond to the amount of light that is decreased by the filter - .3 (1 stop) .6 (2 stop) etc...
07-01-2013, 04:55 AM   #4
Veteran Member
manntax's Avatar

Join Date: Jan 2012
Photos: Albums
Posts: 1,973
You can also buy more flexible ND filters which act similarly to polarizing filters - by rotating one of the layers of the glass you adjust the amount of light you let through - thus reducing stops down. Some also use two polarized filters stacked for the same effect ( since variable ND filters are essentially the same thing - just in slick package - pricey though).

Hope it helps

Last edited by manntax; 07-01-2013 at 05:24 AM. Reason: Edited out the part that was answered while I was writing ;)
07-01-2013, 05:49 AM   #5
Veteran Member
rparmar's Avatar

Join Date: Jan 2008
Photos: Gallery
Posts: 8,783
The terminology is confusing since there are many ways of referring to the same ND filter. All I really care about is the number of stops reduction in light the filter produces. Here is a handy table:

2x = ND3 = 0.3 = 1 stop
4x = ND6 = 0.6 = 2 stops
8x = ND9 = 0.9 = 3 stops
16x = ND12 = 1.2 = 4 stops

And then there is the ND400 filter for about 9 stops of reduction.

As stated above, the ND9 is likely the most commonly useful. A good brand without blowing the bank account is Marumi (DHG series). Of course you need to buy in the correct filter size. I standardise on one or two, say 49mm and 77mm, and then get step-up rings as appropriate to accommodate other lenses.
07-01-2013, 08:10 AM   #6
Na Horuk's Avatar

Join Date: Feb 2012
Location: Slovenia, probably
Photos: Gallery | Albums
Posts: 11,189
So yes, some ND filters make the scene a little darker, others make it a lot darker. The higher the number, the darker the scene. They allow you to use wide open aperture even in bright light (good for portraits) or even to make long exposures in daylight (of the sea, waterfalls, etc.)
Variable ND filters are basically all of those in one package(but of lower quality). A variable ND filter can make the photo a little darker, then you twist it, and it makes the photo a lot darker. But they are usually poor quality or very expensive and can make a weird X across the frame in some cases.
Then there are graduated ND filters, which are a gradient, where one side is dark and the other side is bright. These are useful when you want the sky to be darker and the foreground to be brighter. But they work best with flat horizons. You usually want these filters to be a big square with a holder, so you can move and tilt it any way you want.
Some manufacturers also make filters with a tint, but you probably want to avoid those, unless you know exactly what you are doing. They can make a scene look greener or whatever. with digital photography you can play with the colours in photoshop and usually won't need a tinted filter, except in some cases for flash photography to play with white balance. Some UV filters also have a bit of a tint, like skylight or haze filters. With digital, these serve little purpose, because if you have white balance set to auto, the camera will neutralize their tint. Coloured and tinted filters had a big use back in the film era, though.
07-01-2013, 09:04 AM   #7
Site Supporter
Site Supporter
rbefly's Avatar

Join Date: Oct 2009
Location: Denver, Colorado
Photos: Albums
Posts: 2,030
Try One

Hello Bazinga, Welcome to the Forum!
I think your question has been answered and well-explained. I'll just offer a suggestion:
Buy one ND 8 in the filter size of your best scenic lens, for example your 24mm or 21mm, or a wide-angle zoom. This is likely where you'll be using it most.
Don't skimp on quality, a Marumi or other well-respected brand will be money well spent.
If you don't already have one, get a circular polarizer (CPL) in the same filter size.
Combining those two (stacking) will give you 4 to 4-1/2 stops of darkening, which would turn (for example) a scene of moving water with a normal exposure of f/11.0 at 1/250s to f/11.0 at a 15th or less. slow enough to smooth out the movement considerably. It will have the same effect on traffic, clouds or even people.
Stopping the lens down and/or lowering the ISO can drop the shutter speed even more.
A ND and CPL are the two most-used and necessary filters for digital photography.
07-02-2013, 01:29 AM   #8
New Member

Join Date: Jun 2013
Photos: Albums
Posts: 7
Original Poster
Thank you everyone for your comments you have been really helpful!


  • 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, pentax help, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: Hoya ND filters and Cir-polarizng filters and more... TOUGEFC Sold Items 3 08-09-2012 04:10 AM
Cokin-style ND filters glee46 Troubleshooting and Beginner Help 5 02-09-2011 12:45 PM
For Sale - Sold: B+W 2x ND Filters 55mm X Man Sold Items 4 06-13-2009 03:05 PM
For Sale - Sold: B+W 2x ND Filters 55mm X Man Sold Items 8 11-08-2008 06:44 PM
For Sale - Sold: 72mm filters-- polarizer and grad ND heatherslightbox Sold Items 3 07-28-2008 12:23 PM

All times are GMT -7. The time now is 12:50 AM. | See also:, 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?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]