Best Infrared Filter

<p>I have been searching the internet all day and have yet to find the answer I'm looking for.</p>

<p>I am shooting infrared with a digital camera and Efke IR820 film and a little with the Rollie IR film. My question is what is the best IR filter to use. I am currently using Hoya R72 and am for the most part pleased, and it is the filter I see that everyone else is using. But when looking at other filters like B&W, which has a good reputation for quality I'm wondering if it is worth the upgrade, as i am in the market to get a new filter for another camera. The only concern i have is that the B&W 093 filter filters out all light up to 800nm where the Hoya start at 720nm, does this make a big difference on exposure or the look of the image? Has anyone tested each filter, which is better if there is any difference, and can anyone show examples. </p>

<p>Both Efke and Rollie have a sensitivity around 820nm.</p>

<p>Thanks,<br>

Kiel </p>

<p>The B+W filter will give a stronger IR effect, but will require a lot more exposure than the Hoya. I don't have any of my examples on this computer, but I do know that 720 nm (or 750 like I have) is just barely into the IR range. It is sometimes called near-IR. The main effect here is darkening blue skies to almost black. The white foliage effect will likely not be as noticible. If possible you may want to try to borrow both these filter from another photographer if possible and try both before buying. </p>

<p>The other way to go is to try a Red 25A filter (with a little less affect). The 720 is the filter I use the most of, though I have one that's about 900 something nm, but you can't see through it, and the exposure is crazy long. I'd stick with what you've got for now.</p>

It may be of interest to know that Heliopan make a whole range of IR filters with different transmission characteristics:

http://www.photofilter.com/heliopan_infrared_filters.htm

<p>Heliopan RG715 (715nm) is the right filter for Efke IR820 and the Rollei IR-400 film. But if you have already the Hoya R72 (720nm) the difference is neglectible.</p>

<p>I also use the Hoya R72. When Kodak HIE was still available I useda Red 25, but to get an appreciable IR effect with IR films sensitised at 820 nm I use the R72.</p>

<p>Get a 760nm filter from ebay. The are pretty much opaque. If your eyes are light adjusted and you look at something bright THAT IS NOT THE SUN you will see some light through the filter. Do NOT look at the sun through the filter. It will damage your eyes.</p>

<p><strong>Cheap 760nm filters from ebay work fine for me</strong>. You will of course need a tripod and bracket like crazy to figure out what the right exposure is. I think at f11 or f16 I was bracketing 1 sec, 2 sec and 4 sec on a bright sunny day. I will have to look at my notes. I get a strong IR effect this 760 nm filters. I wouldn't go higher than that. Your exposure times will get ridiculously long and then you will have to deal with reciprocity. Actually at 4 seconds you are already in reciprocity failure territory with Efke.</p>

<p>By the way the nm wave length of the filter is NOT where it starts to filter light. 760nm filters transmit some light below 760nm and they filter some light slightly above 760 nm. It is a sigmoidal curve. It's not a hard cut off.</p>

Thanks everyone, I have purchased the rm72 (is there a different between that and the r72) bacause I know it works but I

also got a cheep set of neewer filters that are 720, 760, 850, and 950 to see what the difference is. Does anyone have

anything to say about the neewer brand filter, consider the price I don't expect much.

<p>This data sheet may be interesting:<br>

http://www.hoyaoptics.com/color_filter/ir_transmitting.htm<br>

As James Smith notes, the nominal nm value of a filter is usually the point at which the filter reaches 50% transmission (which then rises further with increasing wavelength).</p>

<p>Like I said I get a strong IR affect with a 760nm filter. Efke IR820 is sensitive up to 820nm, so I don't see how an 850 or 950 filter will be useable regardless of brand. If you have a modified DSLR I believe the CMOS chips are sensitive up to 1,000nm or 1,100nm. You will need longer exposure times and the IR effect will be very strong.</p>

<p>I am not sure what you are paying for with more expensive IR filters. My understanding for my visible light filters is you pay more for better coatings. You also pay more for neutral colored glass so that the filter does not impart an undesired color cast to your images. The color cast thing shouldn't be an issue with IR. IR light is by definition a different wavelength of light than visible light. I seem to recall reading somewhere that the expensive multicoatings on your lenses are useless when it comes to IR photography. There may be special IR coatings on the more expensive IR lenses. I have no idea. I haven't had any lens flare issues but then again I haven't pointed the camera at anything that would cause lens flare in the IR wavelengths. The other thing is my more expensive filters have brass rings. They NEVER stick together or on the camera. My cheaper visible light filters are made from something else and I have had one get really stuck on an L lens! I got it off eventually but I was pretty frustrated for about half an hour.</p>

<p>Anyway for a rarely used filter I wouldn't break the bank.</p>

<p>If I understand you correctly you have two 720 IR filters. Try them both out and let us know if you see a difference. Do some normal shooting and then try and put them in lens flare inducing situations. I would also be curious to see if there is any difference in contrast. My understanding is poorly coated lenses tend to be low contrast.</p>

 

<p>Hi. I am very new to the world of infrared photography. I am very passionate about it and want to get better at it. I've already tried Ilford SFX film with okay results. <br>

<br />I now have a roll of Rollei/Agfa 400S IR film, and I just got a 760nm filter. I hear A LOT of different numbers from people when they talk about exposure time and it's all quite confusing. My general question is, if you are shooting outdoors on a nice sunny day, with a 760nm filter, what f stop setting and exposure time would you recommend for a really dramatic IR effect (with Rollei 400 IR film)? I know it's going to take some more trial and error, but I just wanted to hear what other more experienced IR buffs would suggest. Thanks!</p>

<p>It depends on the IR light in the atmosphere which you can not measure with any regular exposure meter.<br /> But filtering on 760nm is too far because above 720nm-750nm the Rollei IR-400 is going down in sensitivity a lot.<br /> Which means there is almost no bandwith left so maybe iso 1 - 3.</p>

<p>Here the overview from Digital Truth about some IR films:<br /> <img src="http://farm9.staticflickr.com/8121/8623880851_c718956d19_z.jpg" alt="" width="620" height="450" /></p>

<p> </p>

<p>Thank you Robert. This information really helps me.<br>

So, considering what you said, and looking at the stats for Rollei 400 IR film, I would probably get better results with a 720nm filter, right?<br>

I'm still curious what a good f-stop/exposure time would be. I see people saying that some IR filters require a "crazy long" exposure time, but what exactly do they mean? 1 second? 5 seconds? I just want to know what a good starting point would be. I know there is no quick and fast formula for perfect IR photos, I just want to know what settings most people typically use when they shoot with IR film.</p>

<p>Exactly, a Heliopan RG715nm or Hoya R72 (720nm) will do it. With these filters you can expose around E.I. 12.<br>

If you're running over 1s exposure times you are also entering the reciproke correction for this IR film and then all things are messed up.</p>

 

<p>I have a B&W filter that has a cutoff of 695 nm. I don’t know what exact filter it is, but the glass on it is bright shiny blue. I have used it with both the Efke IR820 (aura and non aura) as well as with Ilford SFX. The lower cutoff is just enough to make your exposure times slightly more managable, while still mantaining a strong IR look.</p>

<p>The difference between a #88A (715nm) and a #89B (695nm) IR filter is one F-stop. But the "wood" effect is less with a #89B filter.</p>