DIY Star Filter

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The best place to get metal screens? Windows. If you or someone you know has recently replaced their windows, you can easily cut out a small portion of the old screens. Otherwise, try checking out secondhand stores for old sifters, especially ones used for very fine confectionery suger. Metal screens may also be purchased quite cheaply at hardware stores in a variety of levels of fineness.

Utility Knife. You'll need something to cut the metal screen with. Wire cutters or even good scissors might also do.

Filter Mount. There are a variety of techniques that you can use to make a DIY filter mount for this filter. This article outlines a number of ideas, including materials needed, construction process, variations, and the advantages and disadvantages of each.

Out of the ones within this article, I would recommend using the “Filter Can” method, as you're not likely to be using too many other lenses for the night photography most people use the star filter for.

Your first step is to prep the metal screen. Remember, the metal screen needs to be shiny, so if it is at all rusty or dirty, first rinse it free of dust and dirt, and then remove the rust using some sort of rust remover. Making sure to dry it.

Once you've got any cleaning out of the way, it's time to cut the metal to shape. Because it's difficult to get the metal screen to glue well, it's a good idea to cut the screen with flaps in addition to what it needs to fit the filter mount, so that once it comes to gluing you'll have extra material to work with.

Next, it's time to attach the metal screen to your filter mount of choice—see the previously linked to article on different DIY filter mounts. Gluing the screen can be a bit dodgy, so make sure you use a lot of glue—but not so much that it obstructs the view of the camera. The flaps you just cut can be wrapped around It doesn't matter too much if the metal screen isn't exactly straight within the filter, so don't worry too much about getting it exactly straight within the filter mount. Also, make sure that however you attach the metal screen that it does not touch the lens. This is important, since otherwise the metal can scratch your lens—which to most people really isn't worth a starry effect.

And with that, you're done!

Star filters are pretty straightforward to use. They work better with night shots, and at that, night shots with a lot of lights. A lot of photographers tend to underexpose their night shots because of how “unpretty” light glare usually is. With the star filter, prevviously lights are instead cheerily twinkling, making them a bit more easy on the eye.

If you try and use this during the day, you'll run into a serious issue: haze. The brightness of daylight will reflect off of the many fine wires of the metal screen and reflect right back into the lens. So, while you might be able to get some interesting effects during the day, it's really not what the filter was intended for.

Starry eyed over this filter, but want something more? It's easy to add more points to your stars, as long as it's in multiples of four. Just add multiple screens that are rotated relative to each other.

If you can get your hands on differently shaped grating, say triangular-shaped or hexagonally shaped, you can create other effects as well. However, this is generally pretty speciality, so don't count on getting it with any amount of ease.

For the inspiration for this article and example photographs, check out this Flickr album.

Picture Credit: http://www.flickr.com/photos/puliarfanita/3287289484/