I have used two different varieties of graduated density filters through the years, glass and plastic. These were either neutral in color (gray) or had colors in them, so I cannot properly refer to all of them as graduated "neutral" density filters. I use them all of the time in my photography to "dodge and burn" my slides in the camera, but most times you cannot tell that I have done this as the blending of the different densities is so even. This is quite unlike television commercials--particularly car commercials--that overuse and abuse these filters to darken (usually with a very distinct demarcation line) or to add some gross color--like red or purple--to the overexposed, overcast white sky.
It makes no sense to add red--or any other ridiculous color to a white sky--where did the red come from? Surely not a sunset, as there is no sun reflection on any of the subjects. Amtrak has done this sort of gimmicky thing in some of its publications, which look especially bad because the water that appears in the foreground shows none of these colors of the skies, which would have been reflected there in real life. I have gimmicked-up some "color-less" photos by using these filters, but at least I have attempted to make the photos seem realistic looking in the process, such as by enhancing Mother Nature's sometimes colorless sunsets, or to darken washed-out skies. I made the photo on the current cover of TRAINS magazine with a Cokin filter-- there was not much sunset color, the sky was washed-out, and the black and white NS diesels added no color, either. I purposely added more color to darken the white sky than to the already dark diesels, and rotated the filter so that the demarcation line ran parallel to the tops of the diesels. Remember, I am not there to record history but, rather, to create visually interesting photos, so please no flames about this (I hear it enough from other railfans). These filters darken everything that shows up in the darker area, so do not attempt to darken the sky BEHIND a church steeple, because it will be darkened as well. I see many images (television commercials mostly) where objects protruding into the top of the image--people, mountains, etc.--are darkened. Anyway, I had Tiffin glass ones that were broken by some rough baggage handling by an airline, so I have opted for the less expensive Cokin plastic ones for many years. They are sharp, but not as sharp as the glass ones. A photographer in my office at CSXT used to combine up to five of these Cokin filters for some beautiful lighting effects, but his slides were not sharp because of all of the air-to-glass surfaces he imparted to the front of his lens. The plastic filters also scratch a lot easier than glass, but are so cheap that I just throw them away from time to time and buy new ones. I am rough on my camera equipment as I take it to some bad parts of town and make it work hard to earn its keep. When using these graduated filters, be careful to blend the dark area of the filter with the light area of your photo. If you use wide angle lenses, very small apertures or a combination of both, the graduated part of the filter will produce a very distinct demarcation line across your photo separating the light and dark areas. You want to keep the filter as "out of focus" as possible to make this blending of densities as even as possible, so shoot medium to wide apertures with normal lenses. With, say, a 24mm lens, shoot only wide open apertures, or thereabouts. Sometimes in extreme lighting situations I will use a pair of filters stacked together, but I shift them a little so that the ends of the two filters' density areas do not align on top of each other to produce a harsh demarcation line. The Cokins come in 1-1/2 and 2-1/2 f/stop differences in densities, so if you stack a pair of 2-1/2 density filters (which I often do), you can get especially harsh results if you are not careful. At times I use a 1-1/2 and a 2-1/2 together. I also not only darken the sky area of photos, but also the foreground area in some photos, so sometimes I will be darkening the top and bottom of a photo with two filters at the same time. An example would be to darken foreground snow as well as the sky, but not darken the subject in the center portion of the photo. I have had MANY instances when a graduated filter with a clear circular area in the middle of the filter would be very useful, and sometimes I have stacked several rotated graduated filters to darken the corners of my photos in odd-ball lighting situations. These graduated filters work great when you are inside a building and need to record the interior as well as something outside an open doorway or window. I made a good shot in the NS steam shop in Birmingham this way, with some electronic flash to properly expose the ends of a stack of flues in the shop, a time exposure of the 1218 sitting inside the building behind the flues, and with a Cokin filter to properly expose the 611 outside the doorway in the backlighted sunset. The graduated neutral density filter allowed me to do this without severely overexposing all of that light coming in through the doorway while I made the exposure of that dark interior. What I like about it is that the photo does not look like it had been manipulated in this manner, and was printed in a magazine with no "dodging and burning" to even-up the exposure, as it did not need it. Buy the larger P (for Professional) size filters. I have the screw-on/slip-in filter holder, but usually hold the filters in front of the lens (actually, pressed up against the lens) by using my left hand. You can get some interesting reflections from headlights and the sun with these filters, so be careful how you hold them. Sometimes I have to angle the filter (so that it is not parallel to the film plane) in order to remove odd-ball sun or headlight reflections that I do not want. Cokin makes some rotating, multi-colored polarizing filter that are interesting for photo illustrations, but you railroad photo purists out there will not like these at all. I found them most useful around ship loading piers for firey, backlighted sunsets. The Cokin filters come in a jewel box similar to a compact disk case. Throw these away, as they break easily and take up a lot of room, just like their CD brethren. Put the filters into a CD carrying pouch such as those made by Case Logic which are available at record stores. Better protection, easy handling, less wasted space. Graduated (neutral) density filters...I couldn't live without 'em. Nuff said. John B. Corns --> SPORRS: Serious Photographers of Railroad Related Subjects X-Mozilla-Status: 0001 Content-Length: 1568
