The work-flow used to create images from the G9 is pretty much the same as when using the Nikon D50 Here!
I have, on the odd occasion, used the HDR technique with colour images, particularly in tricky lighting situations to guarantee a good shot. To achieve this greater latitude you bracket your exposure by 1 or 2 stops over 3 or more frames, thus recording detail in both highlight and shadow areas. It is important to remember to alter your shutter speed and not the aperture, which would result in your image being out of focus. With your consecutive frames safely recorded you will need to blend them together. Photoshop™ has the ability to do this for you; File>Automate>Merge to HDR or you can use the well known HDR Programme; PhotoMatix Pro, now in version 3.0.3RC2. A valuation copy can by downloaded from their website: www.hdrsoft.com
This HDR technique can also be used to capture Infra-red images. The process is just the same; capture a sufficient number of exposures to properly cover the dynamic range of the scene, from the darkest shadows to the brightest highlights. Use a tripod at all times, shoot with available light whenever possible as flash may try to balance the exposure of all the images, when a range of exposures is your goal.
It is important to remember that the number of exposures needed depends on the dynamic range of the scene. For most outdoor scenes, three exposures taken at +/- 2 exposure increment will be sufficient, provided the scene does not include the sun.
Here is a couple taken with the Nikon D50 using the standard kit lens and Hoya R72 filter.
Because I thought them strikingly different I decided to leave them in colour. However, the monochrome ones I did are noticeably pleasing too.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
Regular readers of this Blog site will know from my earlier postings that my preferred choice of camera for Infra-red has been the Nikon D50. For all my other work, landscapes, portraits and weddings, I use Canon gear. Changing camera systems from one to another wasn’t a viable option when I was looking for camera to record Infra-red; I chose the best camera for the job, at a price I could afford. I think I made the right choice.
However, there comes a time when carrying around two systems takes its toll! Unfortunately, old age comes to us all sooner or later. I had three options, give up infra-red photography, switch from Canon to Nikon or find a suitable Canon (infra-red) replacement.
Well! Giving up Infra-red photography was out of the question, so too was changing systems. I had no alternative but to find a suitable Canon replacement. I remember the original Canon D30 being reasonably sensitive to Infra-red, having owned one when they were first launched back in 2002/3. However, I sold my original one to help finance it’s replacement, the Canon D60, which incidentally is not Infra-red sensitive at all.
With my ear to the ground I managed to find, boxed and in mint condition, a 3.2mp Canon D30, ripe for converting, problem was, did I really won’t to spend £200 ($400) on converting it? Mmmmm.. With this in mind I dug out my old Hoya R72 and gave it a try using a 28-80mm USM Lens set at f8/ISO100. I think the results pretty much speak for themselves.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
Having discussed the issues of colour creeping into your Infra-red shots, in my last Blog, I thought I ought to touch on the subject of Channel Swapping. This technique works better with images shot with a 720nm filter, simply because it lets in a fair amount of normal light.
After selecting your White Balance point your image will still normally exhibit a slight orange/reddish cast to the sky area with your foliage showing signs of a minor cyan/blue tinge. This is perfectly normal for this type of filter; some photographers prefer their images this way.
By swapping the Red Colour Channel for the Blue and the Blue Colour Channel for the Red we end up with a totally different looking image, more akin to a frosty winter scene than a psychedelic sunset! For the Infra-red photographer using Photoshop™ as their preferred image editor here are the instructions for swapping channels.
With Photoshop™ running and your chosen image open select Image> Adjustments> Channel Mixer. This will open the Channel Mixer, the default setting should read, Red 100%, Green 0%, Blue 0%. Change the Red Source Channel to 0%, Green 0% and Blue to 100%.
Without leaving the Channel Mixer dialogue box change the Output Channel to Blue and set the Red source channel to Red 100%, Green 0% and Blue 0%. Click the OK box when done.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
False Colour or True Infra-red
Personally I prefer to process my digital infra-red images to have a similar look and feel close to what was achieved when using conventional High Speed Infra-red Film. These were monochrome images with a fair amount of grain, slightly diffused and a little soft on focus. However, there are some infra-red photographers, who disagree and choose to display their work by leaving them in colour. As with any type of photography the option to shoot monochrome or colour will depend on the subject matter, you still have that choice.
How much colour you choose to leave in your Infra-red images will depend on the type of Infra-red filter you use. The most popular Infra-red filter is the R72. This filter has a 720nm rating, which will block out a fair amount of visible light, but not all of it, hence the colour creeping into your image.
If you wish to capture a more traditional Infra-red image I would recommend using a stronger, more opaque filter of around 750nm or higher. A 750nm filter will block out 99% of normal light therefore, letting more Infra-red light waves through, leaving you with a more traditional looking Infra-red image.
If you are considering have your camera converted? Choose the type of filter you want fitted wisely before going ahead with the conversion.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
By spending some time with your RAW conversion software and understanding what tones give you the best white balance settings will undoubtedly pay dividends in the long run. With practise selecting your white balance point will become second nature and have a marked improvement on your infrared images.
Fig:1 shows the .NEF file straight off the CCD. As you can see the image is very red, but at the same time showing a full range of tones. To correct the cast we need to select a white balance point from a mid-tone grey. For this image I made my selection from the barrel timbers. Selecting a mid-tone brick from the wall would have given a similar pleasing result.
Fig:2 shows the image after the white balance point has been selected and the exposure re-adjusted to stop the whites from blowing out.
You now have a basic infra-red image from which you can work on. You may wish to convert your image to monochrome, add a touch of grain, maybe a little Gaussian blur to give it that authentic Infra-red Photography look and feel.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
In order to get the best possible results from your camera and the infra-red images you take, you will need to shoot everything in RAW (NEF), this is not an option, but a necessity. Why? because you have better control over the final exposure and complete control of your white balance settings, which, when shooting in infra-red is vitally important, as you will see later in this section. I preferred to let Nikon's 3D-Matrix II metering system take care of my exposure, it's not that often it gets fooled. Your main consideration, when shooting infra-red images with a non-modified camera should be that of camera shake! always use a good study tripod, again this is a necessity, not an option!
Because our camera lenses are designed to work best under normal lighting conditions and not under infra-red radiation, there is a slight point of focus shift. Some older lenses will have a red infra-red focusing dot, newer ones may not. To compensate for this focus discrepancy it is best to stop your lens down to a small aperture (f22) thereby maximising your depth of field. By focusing on the most important element within your composition, out of focus images have never been a problem for me using the above equipment and working practise.
Filters, Internal & External Infra-Red
Because infra-red radiation contaminates images taken under normal conditions modern day digital cameras are fitted with a cut filter, placed in front of the censor to filter out most, if not all infra-red wavelength's. However, some digital cameras are still quite sensitive to Infra-red even with this cut filter firmly in place, notably the Nikon D50, although exposure times will be quite long, even under bright conditions.
If you only ever use your camera for taking infra-red images you may consider having the cut filter completely removed and an infra-red filter put in it's place. The benefit of this procedure is two fold, first, exposure times will be greatly reduced, from seconds to fractions of a second and secondly, you will be able to see the scene before you, in the camera's viewfinder window, all be it slightly reddish.
If, like me, you are happy enough to leave your cut filter in place and not have your camera modified you will have to place an infra-red filter across the front of your lens. The filter I use is made by Hoya, an R72 type. The R72 will block out normal wavelength's below 720nm.
Composition of your subject is made without the filter in place, for the simple reason, the filter is opaque and you can't see though it. With your camera firmly fixed to a tripod, compose your shot in the normal way and refit the filter before making your exposure.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
My first venture into digital Infra-red, back in 2003/4 was with a 2mp Olympus C-2020, possible one of the most sensitive cameras to Infra-Red, without any internal modifications. The C-2020 and a Hoya R72 were a formidable duo. Once you mastered the art of channel-swapping you were home and dry with this little beauty. The only problem being the small image size and the lack of RAW shooting.
By this time I had decided that I wanted a camera, which was small and light, would work equally well with normal photography and infra-red. Last, but by no means least, I wanted something that wouldn't break the bank! Enter the Nikon D50. The D50 delivered on all counts. It's 6.1 megapixel censor produces excellent 16" x 12" prints, the large LCD screen makes for easy viewing and the battery life from the EN-EL3E is phenomenal.At the end of the day, without putting to finer point on it, the camera is but a tool, a means to an end. The most important criterion is being able to see the potential in a shot, to envisage the final print before tripping the shutter. Nonetheless, any of the 6.1mp Nikon's will do a very competent job of shooting Infra-red.
Use the Infra-red Archive to discover more about the world of Infra-red Photography
