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Friday, May 4, 2012

Photographing in Invisible Light: Infra Red Light

Photographing in Invisible Light: Infra Red Light

The ‘normal’ light conditions are available in general situations and it been estimated that an overwhelming majority of 98% photographs are taken in visible light.

However, as elementary physics has taught us the range of light goes much beyond the normal light. Normal light has wavelength range of 400 nm to 780 nm. As we move towards the shorter wavelength bandwidth we enter the ultra violet range and as we move towards longer wavelength we encounter Infra Red (IR) light bandwidth with wavelength approx. 300 micrometers.

Most of the modern day digital cameras are sensitive to IR light are capable of capturing images in IR bandwidth.

But, why bother with capturing photographs in the IR? The answer is simple: the resulting images are surreal and almost magical in appeal. The normal photograph with green leaves and grass of the foliage suddenly transforms into silky white scene with type shades for other objects.

Once, simple way to find if your camera can shoot / capture IR images, just point your camera towards your TV remote and if you can see a white spot emitting from the remote, then your camera can shoot / capture IR. Else, your camera is not sensitive to IR light and will not capture any such images.

IR Photography has been used by the experts in the field of military and widely for astro-photography for a long time. Digital photography makes it real fun and easy to capture photographs in IR and that alone can be compelling reason to try IR photography as a hobby and a new avenue to experiment.

The most common IR bandwidth that will of interest to us is wavelengths between 700 to 1000 nm. This Near Infra Red (NIR) range is commonly captured by modern day cameras; both point and shoot as well as D-SLR.

In the years gone by, there was IR film used by yesteryears photographer to capture IR photographs. The IR camera rolls being more sensitive to light; require special handling in the dark-room, making the process cumbersome and daunting for even the most experienced ones.

IR Enabled Camera:

In some of the modern day digital cameras, there is an additional special filter over the image capturing sensor, that blocks most of IR light and allows only visible light to pass through. This filter is called IIRC – Internal Infra-Red Cut Off filter, which can removed by specialized training personnel in the select camera repair outlets. The resulting digital camera becomes a dedicated IR camera and cannot be used for conventional photography, thereafter. But, for the IR photography enthusiasts, this becomes a valuable possession and these cameras are much more sensitive to capturing wider range of IR spectrum and producing images of highest quality.

Post-Product IR Option:

 Since, not everyone wants a dedicated IR camera, the most popular option becomes to convert a ‘normal’ photograph to IR simulated one.

Here are the steps in one of the most popular editing software – Adobe Photo Shop:

1.       Using any D-SLR, capture a photograph in the B/W mode. Most, of the D-SLR cameras have this option. Converting a color image B/W in editing software, with result in loss of IR range covered.
2.       Use TIFF format instead of JPEG, to get best results. You can easily convert a JPEG to TIFF.
3.       Open the image file in Adobe Photo-Shop
4.       Open the Levels dialog window (Image > Adjustments > Levels) and adjust as needed by dragging black triangle just under the left edge of the graph and the white triangle just under the right edge of the graph.
5.       Review the changes in image, so that you get the look you want.
6.       The next step is to convert the file from RGB to Grayscale (Image > Mode > Grayscale). Click OK to discard the color information and create a file that looks like a black-and-white IR photo.

This is one of the simplest way to convert a B/W photograph to IR one. For higher quality results it is best to shoot in RAW mode of the digital camera and convert it to 16-bit TIFF.

Visit: Industrial Photographer for many commercial photographs

Composing Perfect Photographs

Composing Perfect Photographs

With easy prevalence of digital camera, taking photographs have become an almost spontaneous act, especially for youngsters armed with mobile phones with camera and very affordable point-n-shoot camera, at every instance of viewing or witnessing anything remotely ‘interesting’.

However, sadly the quality of the vast number of these photographs is poor not only from the technical aspect but also from compositional and aesthetical point of view. 
Group Photograph

Every photograph that is appealing to the viewer and eye catching must be well composed. So what is ‘composing’ all about?

A well composed image / photograph is the one that adheres to the basic principles of photography in terms of quality & quantity of light, angle of subject vis-à-vis photographer, location, ambience in which the photograph is taken.

One of the most important factors in composing a good photograph is light. After all, photography is all about light. The word photograph is derived from two Latin words – photos meaning light and graphos meaning writing / drawing! The following points have to be kept in mind:

  •  What is the source of light? Is it sunlight or artificial light?
  • Can the source be manipulated to compose the photograph?
  • Is the subject required to be evenly lit?
  • Is the exposure correct for the intensity of the light?
  • Can this photograph be can in out-door location or vice versa?

The photographer will have to analyze all these factors and in-fact many more depending on the final results desired or visualized. With all these variables, it does an challenging aspect to take a well composed photograph.

Let us take an example of taking a photograph, taken during evening / morning hours. The hour or so, before and after the sunset and sunrise respectively is known as ‘golden hour’. The reason being that, during this period, the light is soft resulting in soft diffused shadows and the climate generally being more pleasant, the scenes are more serene looking and eye pleasing, as compared to any other time of the day, when the sun is up in the sky, resulting in squinting of the subjects eyes along with other discomforting factors like sweat etc. due to bright sunlight and increased mercury levels.

With soft sunlight falling evenly on the subject, the photographer with his / her back to the sun can take some well composed photographs with best results from prime lens that have fixed focal lengths, mounted on a Digital SLR camera. For best results, it is highly desirable to mount the camera on a sturdy tripod, thereby preventing any camera shake what so ever.

The same principles can be applied while on vacation with friends and family to take photographs near monuments, tourist places and group photographs. The industrial photographs may or may not have people as the central characters and focus can be placed on capturing the location only.

Another popular way to take well compose photographs is under overcast skies! Most of the photographers shy away from clicking in this situation, but it does not always rain when clouds are covering the sun. With diffused sunlight, there are no deep and dark shadows to worry about and the result is an eye pleasing photograph.

The amount of expertise required for composing a well balanced photograph is studio setup is another challenging and specialized field of studio portrait photography. 

Check out some well compose photographs by industrial photographer - Pashminu