Expanding the Filter Experiments!
Several months ago I posted a short little article on the B+W 403 UV/IR band pass filter. There has been a lot of activity on this recently so I thought that I would revisit the subject. When using a Full Spectrum Infrared converted camera system the 403 bandpass filter is a viable option for some very ethereal images. BUT, you can ONLY use this filter group on a full spectrum camera. The reason for this is that any internal infrared pass filter will block the UV portion of the spectrum effectively blocking the effect that these filters can provide.
The hallmark of this filter family is that you get deep blue/purple skies along with stark white tree leaves and grass. This can produce some very good and interesting images that is very removed from your normal infrared work.
As you can see, the sensitivity of the UG1 is much less than the B+W 403. This means that your images will require much more light entering the lens for a proper exposure so keep this in mind when you choose which version you are going to purchase.
Now, compared to the other Infrared spectrum’s like 590nm, 665nm, and 720nm, the 403 has a 8 stop reduction in its light transmission. You will likely have to use a tripod when using this filter or hope for a very bright day!
For images using these filters you will get blue/purple skies and bright white monochromatic leaves. There is no channel swap needed and the only real post processing needed is to adjust the hue of the sky color. For this I really like using NIK’s Viveza plugin.
Here are three examples that I took of the scene in my last post on the Tiffen 47 filters for in camera Faux Color Infrared images. I did this so that you could compare between the 2 filter systems.
Look at the detail in the sky and leaves. The bright whites give a very stunning image and the blues look very good. I really like this image due to the sky detail and the blue water.
Please keep in mind that these three images are strictly test images for this post and not meant for artistic value!
As I said earlier, this filter can give a very etherial image that your viewers can loose themselves in. The camera system will have a tendency to over expose a stop or two so take that into account as you setup and take your images.
White balance is done on Green leaves so look for a green tree or for grass and use it to WB your camera system before you start shooting!
Please let me know what you think of this filter. It is a rather expensive filter as are all that are opaque to our vision! Expect to pay over $100 for this any larger than 50mm.