What is the recommended IR Filter to use for a start ?

Hi All,

I'm eager to try IR photography using my D70s.

From what I've heard, D70s should be OK with IR photography as not every camera

is. However, I still need the IR Filter.

I was looking for Hoya R72 52mm (to match my 50 f/1.8 and 18-55 VR) but it

seems to be out of stock every where I look. Equivalents from B+W or Tiffen

costs approximately twice the Hoya. Any idea why ?

Amazon / eBay offer a filter made by Opteka, anyone tried that one ?

I'd appreciate it if you could recommend on what filter / brand to start with...

Thanks,

Oded

Hoya has supposedly discontinued their R72 and RM90 filters. B+W has two filters, the 092 and the 093.

The B+W 092 should be avoided. Although often listed as an equivalent of the Wratten 89B or Hoya R72, it actually passes much more if what I call BVR (for "barely visible red") a deep red that, although barely visible to the human eye, causes IR sensitive cameras like your D70 to produce results dominated by the red channel. The resultant images are lacking in resolution, difficult to process, and do not have as dramatic darkening of skies and lightening of vegetation as a better IR filter will.

Aside from the B+W 092, IR filters fall into two groups, which I typically refer to as "weak" and "strong".

Weak filters (aka "Wratten 89B family" filters) are the real Wratten 89B and all it's true "clones", the Hoya R72, Heliopan 715, H&H 89B, and Cokin 007. They begin passing IR just above the threshold of visibility, a wavelength around 700nm. These filters all produce IR images with the best IR response in the green and blue channels, with excellent bright foliage and clouds, dark skies and water. There is a slightly stronger response in the red channel that includes a mix of IR and BVR. Since you have response in all three channels, you have full resolution. Images can be processed into "false color" infrared: yielding amber clouds and light blue foliage, or done as full B&W. Exposures are reasonable, under a second on a D70.

Strong filters (aka "Wratten 87 family") like the Wratten 87, 87A, 87B, or 87C, Hoya RM90, Tiffen 87, Lee 87, or B+W 093 don't pass substantial IR to somewhere around 800-900nm (depending on the particular filter), wavelengths that produce the strongest infrared effect, with little or no "false color". The infrared effect of contrast between cloud and skie, vegetation and earth is about as dramatic as it gets. You can use the D70's "preset white balance" with these filters, and the image will show on the LCD as a very clean B&W. Exposures are 4-8x longer than with the weak filters.

The least expensive filters, if you want round glass filters, are the H&H, at about 1/2 the cost of Hoya. The least expensive filters, period, are the Cokin 007 for a weak filter, and the Lee polyester 87 for a strong filter.

As to the "why" of cost:

Lee are polyester film, very cheap.

Cokin are cast acryllic, pretty chep.

H&H are gelatin (very cheap) glued between sheets of clear optical glass (pretty cheap).

Hoya are high quality Japanese optical glass "dyed" (colored by mixing chemicals into the molten glass) dark colors, so are pretty expensive.

B+W and Heliopan are German dyed optical glass, and are therefore outrageous.

Tiffen is, well, Tiffen, and will never make sense to me.

wizfaq

Thanks Joseph for the very thorough and educational answer. This did clear some of the fog :-)

Say, would it be possible for you to post some samples taken using different filter kinds (i.e. different wavelength) ?

Thanks !

Dan, it's possible, but insanely difficult. You may end up with 30 second, ISO 800 exposures that take a ton of post processing.

Obed, you're welcome. I'll see what I can do about some images. Might not have a chance untill the weekend.