Friday, April 6, 2007

IR for Beginners - But, I don't own a DSLR, can I shoot IR?

Ok, we’ve talked about the DSLR’s and what can be done with them, both in a factory stock configuration, and modified for IR-Only.

So what about all of the other Digital Cameras out there? the point and shoots? the prosumers? the pocket digital cameras? Cameras that do not have interchangeable lenses, and have Real Time Displays. We’ve already stated that IR Photography is possible with just about any digital camera, regardless of its class.

I really don’t like to apply labels to cameras as far as to their class, but it will be much easier to just call these cameras “Prosumers” for purposes of this discussion, so I will use that term here.

If the camera does not have Full Manual Settings and Lens Threads for Filters, the camera is not a good choice to work with. So, although technically capable for IR, practically, the lack of these two critical features eliminates a lot of camera models from consideration, especially the lower models and the pocket size models.

Why are these features so critical?

Well, just as with the un-modded DSLRs, IR exposures with un-modded Prosumer digitals will be rather long, and require use of a tripod. If the camera is fully automatic, without Manual Settings, you will not be able to set it to take a long enough exposure to get an IR Image.

You will also need to be able to attach an IR Pass filter onto the lens, so if the camera does not have lens threads, it will not be very practical. I suppose there’s always Duct Tape.

So, do a quick evaluation of your camera before you go out and buy a relatively expensive IR Filter. You might want to acquire a different model, and it could easily require a different sized filter. Do your homework.

Assuming that your camera has passed this muster, and you have purchased an IR Filter and a sturdy tripod, how will you go about getting an IR image?

Remember from our previous discussion of “Fighting Filters” you will be shooting thru both the IR Pass filter and the internal IR Block filter in the camera.

With your un-modded Prosumer digital, you will have a real advantage over your neighbor who is shooting an un-modded DSLR.

Your Prosumer has a Real Time LCD display, and most likely a Real Time Electronic View Finder, or EVF. These 2 devices will allow you to bypass most of the steps that your DSLR friend must make.

1. Place your camera on your tripod.

2. Screw on the IR Pass Filter.

3. Long Exposures tend to produce more Digital Noise, then short exposures, so set your ISO to the lowest available on your camera, to avoid the noise as much as possible.

4. Set the camera for Manual Settings.

5. Adjust for a mid-Aperture setting, usually around F4.

6. Then adjust the Shutter Speed until your camera’s internal meter reports Zero EV.

You will probably start off not being able to see any image on the LCD or in the EVF, but by the time that you get your exposure settings to Zero EV, you will have a Real Time view of your image on the camera. You can then finalize the composition of your image using the Real Time View.

This is a Huge advantage over your DSLR using neighbor. You will be seeing your image in IR rather than visible color light, and you will really be able to see how objects such as foliage, sky, water, and other materials reflect the IR light, and will look in your final image. Your composition can be adjusted in Real Time.

Depending on the camera, you will most likely get an image that is heavily reddish, or mostly purples, or Bronze in color. You will work out the colorations in Post Processing, or convert to B&W in your editor later. Post Processing is as much a part or IR Photography as is taking the image.

It’s worth pointing out that many of the Prosumer models were produced prior to the current flock of DSLRs. The internal IR Block filters installed in the early cameras were not as aggressive at blocking IR light as are the IR Block filters in the more modern cameras, especially the DSLRs. So, where a DSLR might take a 10 second exposure to gather enough IR light thru the blocker to get an image, the Prosumers usually require much shorter exposure times.

As with the DSLRs, you may want to experiment with setting a Custom White Balance. Do the WB off thick green grass or some other foliage or object what will reflect white in IR. Or try some of the built-in WB settings included in your camera.

IR Photography is a constant Experiment, both in acquiring the image and post processing it.

How about having your Prosumer modded to remove the Internal IR Block filter? You should first check with the companies who do these mods professionally. You will find that they usually offer mods for a very select group of Prosumer models. So, investigate which models may be modded to see what is available to you.

If you find that your camera is one of the chosen that can be modded, you have, unlike the DSLR owners who have mods done, an extra choice to make.

When the professional removes the Internal IR Block filter, he may replace it with either IR Pass Filter material, or with Clear Optical Glass.

If you choose to install the IR Pass Filter material, your camera will be IR-Only from then on, just like the modified DSLRs. You will not need any screw-on filters to take IR Photos.

Prosumer owners, who choose to have their camera modded, most often decide to have the Clear Optical Glass installed. This will give you 4 separate modes with which you can experiment.

1. Shoot without any filter at all, allowing Visible Light and IR Light mixed to be recorded by the sensor. You can get some interesting effects and colors.

2. Purchase a screw-on filter of the same IR Block material that was removed from the inside of the camera, install it on the lens, and shoot regular Color in Visible Light, just as you did before the modification.

3. Purchase a screw-on IR Pass filter, such as the widely used Hoya R72, and install it on the lens. You will be shooting in IR with full camera aperture and shutter speeds available to you.

4. Try various colored screw on filters for full-on, no-holds barred Experimentation.

Bottom line, there are many, many cameras that can be used for IR Photography. A DSLR is not required, and as you can see from this discussion, the Prosumers have some significant advantages to offer.

-=- Jerry -=-
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