Monday, August 27, 2012


Exploding the Myth.
There has always been an air of mystery about infra red photography. Perhaps justified in the days of film but wholly unwarranted now that digital cameras have made things so much easier.
That which we call light expands on wavelengths to each side of what the human eye can register. Light on the shorter wavelength is Ultra Violet and on the longer wavelength Infra Red.
Digital cameras with suitable filters that will stop “our light” can record light that we cannot see. For taking pictures the filter requires to stop light lower than say, under a 700 nanometre wavelength from registering. The filter used will seem to be black to us but it allows infrared light to pass through and record on our digital camera. Basically the darker the appearance of the filter the higher the number, but also the longer the exposure required to register an image.
I found that a Hoya filter numbered 72 needed an exposure in normal sunny conditions of around 20 seconds at f8. Now this is a time consuming action, because I always bracket by at least a half under and a half over exposure.
This you can see needs a 10 second, a 20 second, and a 30 second series.
However to be certain of getting a useable picture it is well worth spending the time.
Another point is that our eyes adapt to light conditions so that it can be hard to guess exactly how bright [or dull] the day is. For this reason I set up my Weston Master 5 light meter and did a test series. I found that with the light recording at 12 it required 20 second at f8. I set the meter to read accordingly and now I have an accurate exposure time for any light condition. If the light goes to 13 then the time changes to 12 seconds. The light drops to 11 the time goes to 30 seconds and so on.
Many of the old lenses had a small red dot on them to change the focus point to IR. As we will be working at manual on our camera we can use these lenses in spite of them maybe not being auto focus. Focus manually get the distance and then move the focus point to the red dot. Easy isn’t it?
Now we come to editing. It can be simple or involved depending what you want the finished image to look like. A lot of the mystery of IR is founded on the fact that the image comes out red.
So what? Our editing programmes allow us to change digital images to greyscale very easily. I work with Paint Shop Pro 8 with no problem. However when you change to greyscale you cannot treat the image as though it was coloured. If you make a 10% sepia change afterward though in Artistic Effects you find that the picture is then recognized as a colour image in spite of very little change of tone.
One of the options in PSP8 is Enhance Photo. Click on this and you will find most of the things you wish to do. 

One step photo fix.
Colour balance
Saturation
Clarify.
Those four actions can cover a lot of editing. I make it a point to seldom write over the original red image. I save the new image with a short addition to the DSC number. Such as –sat-grey-step-clar. In some changes I also put the number of colour balance change. 



 
 

Here is an example of greyscale to the IR image with a very light touch of yellow coloured edges from PSP8 Artistic Effects

When I upgraded my digital camera I had my Sony A350 adapted to take only infrared pictures. I was made aware of the firm that did this in England for just over £300. As my interest in IR had increased I thought it well worth the cost to be able to carry with me the choice of instant IR pix rather than going through the cumbersome and time wasting changeover and necessity for using a tripod. As I am able to set the camera to •7 for under and over bracketing for a 3 bracket exposure it also saves a lot of time. It is almost always the first exposure that is the best, but it is worth the extra to be certain by having the choice of the others if needed. Focusing is also more accurate and the short exposures stop the blurring of foliage in the wind.
It also permits taking casual pix just “in case” they might turn out to be of interest when editing later. One instance was an old cottage that looked to be a possible picturesque scene but lacked enough bite when changed to grey.
A little jiggling when editing by using the Flood fill tool in PSP together with judicious use of light blue coloured edges produced a suggestive shot of a moonlit lane with an intriguing sense of mystery about it.
20 minutes of work by jiggling has produced a reasonable pic from a failure, as well as allowing practice of editing skills I called this one “Ill met by Moonlight” from the suggestion of creepiness in the way the formerly bright sunshine has been changed to blue
An Infrared pic does not have to be purely monochrome as this one shows.
Driel Church in Gelderland Holland, from the Westerbouwing heights on the other side of the Rhine.

However monochrome or sepia allows a building to stand out simply because stone absorbs little infrared light like the chlorophyll of a plant does. It is this that makes the tower of Driel Church in Holland stand out from what normally would be a mass of various shades  of green.
So why not have a try? You will find it intriguing and maybe mystifying to see the difference that infrared can make to scenery around you. Views that have become blasé take on a new appearance in infrared and can give an inspiration and freshness to your picture taking.

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