After all the good information given by Larry and Frans about IR photography, I thought it might be helpful to share some of the pluses and minuses I have found using two different ways to make IR photos with the D70. The following repeats much of what they said but is a direct comparison between using the automatic, easy approach of the R72 filter (alternative filters are Hoya 89B or B+W 092) and the slightly more complicated but possibly more pleasing results using the very dark 87C filter (alternative filter is B+W 093).
I began pursuing IR photography by purchasing from B&H a Kenko filter holder($40), a Kodak Wratten 87C gel filter($58) and a 67mm to 62mm step down ring ($23) to attach to the 18-70mm D70 kit lens. After much fooling around with different times (5 sec. 2sec and 1 sec) combined with different F settings (f/5.6 to f/11), I started getting excellent results using the following settings on JPEG fine or Raw.
Workflow for the D70 shooting IR with 87C filter
1. Set the camera to manual on the mode dial but also change the focus mode selector switch on the camera body from AF to M and the autofocus manual lever on the lens from M/A to M. (remember to return the body and lens switch to AF and M/A when you are through taking IR shots and want to take regular photos again.)
2. Leave the White Balance on auto
3. Using the command dial, change the exposure timing to 1 sec or 2 seconds.
4. Using the sub command dial, change the f setting to f/5.6 up to f/11. Try different settings to see what you like best.
5. Turn the focus ring to either 50mm or 70mm. If you go below 50mm there is the strong probability that vignetting will occur which you will see as dark edges at the corners of the shot. Some shots taken with long exposure times (like 5 sec) appear round with a dark circle around the whole photo.
6. Attach camera to a tripod, compose the shot, attach the step up ring, filter holder and gel filter and shoot. (If you want to take a color shot first, then follow with an identically framed and composed IR shot, you have to change the manual setting to something like 1/250-500, f/11, etc. for strong daylight then reset for the IR shot. This gets a little cumbersome so I did not take many comparative color shots.
Workflow with the D70 and the R72 IR filter
Then, after reading what Frans suggested, I purchased a new 67mm R72 screw on filter at Ebay for $56. I have followed his suggestions and set the camera on JPEG fine or Raw, auto focus, auto white balance, auto ISO 200. Good shots were possible by hand holding the camera but it is hard to get identical color and IR shots hand held. Using a tripod, allows you to compose, shoot a color shot, screw on the filter without disturbing the compositon, then shoot the IR.
Importing and editing in Photoshop
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