Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
04-07-2015, 01:03 PM   #1
Forum Member
Capture Lights's Avatar

Join Date: Mar 2014
Posts: 80
Are infrared filters stack-able?

I was just wondering, say if i stack two 720nm infrared filter on top of each other, what will be the result? anybody tried this?

will it be an 1440nm infrared? or still 720nm, but just darker? or what's your experience with stacking infrared filters?

04-07-2015, 01:23 PM   #2
Loyal Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 5,413
Should just make it darker, since both filters do the same thing - only allow the 720nm wavelength light. Perhaps the stack will be neutral but I'd bet they will add some light blocking (I could be wrong if the filter is good enough).

Think about stacking multiple layers of colored glass, for instance. Still the same color of light shining through, but unless that transmittance is very high you will get some loss.
04-07-2015, 01:37 PM   #3
Forum Member
Capture Lights's Avatar

Join Date: Mar 2014
Posts: 80
Original Poster
hum, if that's the case, then there's no point of owning two sets of 720nm infrared filters =) thanks terry

anybody tried this out?
04-07-2015, 01:42 PM   #4
Pentaxian
redrockcoulee's Avatar

Join Date: Nov 2009
Location: Medicine Hat
Posts: 2,097
QuoteOriginally posted by Capture Lights Quote
I was just wondering, say if i stack two 720nm infrared filter on top of each other, what will be the result? anybody tried this?

will it be an 1440nm infrared? or still 720nm, but just darker? or what's your experience with stacking infrared filters?
Each filter was designed to omit light below 720nm, there is no way that stacking them would stop the ability of light at or above 720nm to pass through s othe answer is no, only less light hence longer exposure

04-07-2015, 02:02 PM   #5
Forum Member
Capture Lights's Avatar

Join Date: Mar 2014
Posts: 80
Original Poster
sounds convincing, i was thinking getting another one of those filters that a friend was giving away, it seems it would be more useful for someone else since i got one already.
04-07-2015, 03:03 PM   #6
Loyal Site Supporter
narual's Avatar

Join Date: Jun 2013
Location: South Bend (Notre Dame), Indiana
Posts: 1,935
No one needs to try it out. It's basic physics. colors are a shorthand description for wavelengths.

This is like asking if putting 2 green filters on a lens will make it let orange light through.
04-07-2015, 03:10 PM   #7
Loyal Site Supporter
AquaDome's Avatar

Join Date: Jan 2014
Location: New Carlisle, IN
Photos: Gallery | Albums
Posts: 1,399
You can stack them. The result is less light, thus a longer exposure. Many of the less expensive IR filters only give you two stops, so I bought two of each to get four stops of density.

I wouldn't attempt to stack more than two filters - you would likely begin to see vignetting in your photo.
04-07-2015, 03:28 PM   #8
Forum Member
Capture Lights's Avatar

Join Date: Mar 2014
Posts: 80
Original Poster
QuoteOriginally posted by narual Quote
No one needs to try it out. It's basic physics. colors are a shorthand description for wavelengths.

This is like asking if putting 2 green filters on a lens will make it let orange light through.

QuoteOriginally posted by AquaDome Quote
You can stack them. The result is less light, thus a longer exposure. Many of the less expensive IR filters only give you two stops, so I bought two of each to get four stops of density.

I wouldn't attempt to stack more than two filters - you would likely begin to see vignetting in your photo.
thanks, i've plenty of nd filters, so ill just use those to cut down more light if needed.

04-07-2015, 04:34 PM   #9
Loyal Site Supporter
AquaDome's Avatar

Join Date: Jan 2014
Location: New Carlisle, IN
Photos: Gallery | Albums
Posts: 1,399
ND filters are not all equal when it comes to blocking IR. I use ProStop IRND filters.
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!
720nm, camera, filters, pentax help, photography, troubleshooting
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Opteka/Cokin Infrared Filters? jfsavage Pentax DSLR Discussion 23 02-29-2012 11:11 PM
When are we supposed to be able to buy Polaroid film again? jct us101 Non-Pentax Cameras: Canon, Nikon, etc. 10 04-08-2010 12:36 PM
Lightroom 2 - auto stack RAW with JPEG? Propagate changes through stacK? Eruditass Digital Processing, Software, and Printing 13 09-24-2009 07:35 AM
For Sale - Sold: Super Deal on Lightly Used Infrared Filters! MikeDubU Sold Items 7 02-20-2009 02:06 PM
Should we stack ND filters? raider Photographic Technique 25 11-13-2008 05:08 PM



All times are GMT -7. The time now is 02:48 AM. | See also: NikonForums.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