How to take sharp and focused photographs – digital photography tutorial
Sunday, May 3rd, 2009Sharpness is a topic that effects every digital photographer from the wide-eyed beginner to the experienced professional, so, let’s look at how you can obtain the sharpest images possible from your digital camera.
The Right Glass
The first question many people consider when buying their digital camera has to do with the amount of pixels there are in the images the camera produces. While this is important, it is not the be all and end all of the matter. Far from it. I discovered in 2005 that megapixels don’t matter as much as many think they do.
This discovery came about when I finally realized that my fantastic high resolution sensor camera was actually not producing sharp images. It turned out that it was not the camera sensor at all but rather the optics I was using at the time. The lenses I attached to my camera were originally designed for 35mm film.
As soon as camera sensors offered 10MP and more, we were ‘out resolving’ the old optics. Hence, in recent times, you will have noticed all the camera manufacturers releasing many new lenses with digitally oriented optical technologies.
Lenses are the predominant precursor to obtaining a sharp result. The good news is that all lenses are computer designed, this helping to eliminate defects. Even the cheapest lens can offer good quality results, if they are used correctly. However, the old adage ‘you get what you pay for’ is a true statement. For example, I have shot with lenses most of my life that are not necessarily the best available. Often the reason is weight. I travel regularly and the more expensive lenses are larger and heavier. I will explain further soon.
These days digital SLR cameras are usually sold as kits, complete with one or two zoom lenses. Usually, that is a camera body with a standard zoom lens and a telephoto lens. Kits are great as they offer fantastic value. The lenses in these kits are usually very good. But, they are often to lower specifications in terms of optics and construction. The good news for those who have bought such kits is that they have had a few years use of good equipment which has helped them to learn and grow their photo skills.
However, eventually the kit user will want to go that next step. It is at this time that a change of optics will make a difference to their photographic future. Lets say you have two lenses of a similar nature - a kit 70-300mm f4.5/5.6 lens for $400 and a 70-200mm f2.8 at $1,400. At A3 size, I could guarantee that you would not pick the difference in sharpness (detail) at f11 between the two lenses. So why would you consider the more expensive lens?
When you look more closely at the images, there are differences. If you photographed the same subject with both lenses at f5.6, the 70-200mm lens will out perform its cheaper cousin. The image will look sharper from edge to edge when compared to the cheaper lens.
Another feature of the more expensive 70-200mm lens is that it allows more light to the sensor for low light shooting because of the wider maximum aperture. I can not stress how important it is to buy the right lens for your interests. The 70-200mm is a great lens for people/portrait shooting and general photography.
Horses for Courses
I have always used a lens that does not require a converter. My current Sony 70-400mm lens is very sharp throughout the range. I can still use it for portrait shoots and importantly for me, for action work in Africa or similar. It shoots a pin sharp image for landscapes as well. Most camera manufacturers offer such a range (70-400mm) and others like Tamron and Sigma have very good alternatives.
My point is, to use the right lens for the job. When would you spend more money on a lens? If you are printing small images regularly with just the odd larger A4 or similar print, most current lenses will offer great results. However, if you aspire to the best results and or you print to large sizes, then the best optics will be required.
Shooting Techniques
Of interest, for the more seasoned photographer, is the fact that I try not to use a tripod as much as possible. This is a very personal preference and I understand that it goes against ‘the text book’ philosophy. However, I have found that it offers me far more creative freedom. Sometimes the ability to move a couple of centimeters up and down, left and right can make all the difference. Of course I use a tripod for some subjects like waterfalls, late evenings or for special creative shoots. But for most of my work, I prefer the hand held method. Because that is the case, I have a couple of key points to sharp results while taking pictures hand held.
1. Hold your camera correctly. From the example images you can see that the photographer is slightly side on to the shoot angle. Feet are spread a little. 2. Stabilise your body. Left hand is ‘your tripod’ with the camera placed in a nice balanced position. This will depend on the lens you are using. 3. Combine the above at the moment of shooting. This is very important and a key to my ability to shoot sharp images even at slower shutter speeds. I hold my breath and gently squeeze off the trigger.
4. Use your Depth Of Field. Three things control your depth of field - choice of aperture, choice of lens focal length and camera to subject distance. A limited depth of field with the right techniques will offer a limited sharp area, highlighting the subject against an out of focus background.
It’s in the Post
There are also several ways to enhance the sharpness when you get your image into the computer. This has a few variables but I work on a strictly ‘Keep it Simple” system.
If you are shooting JPEG files - These files are processed in camera with sharpening being one of the parameters you can set up in your camera if you wish to. If you are shooting RAW then you are dealing with files that have had no in camera processing. I shoot nearly exclusively in this format and have done so for several years. These files definitely need sharpening unless you are after a softer look.
Different camera brands should be treated differently. For instance, Nikon images require less sharpening than Canon files. Sony files are similar to Nikon files…which makes sense when you think of where Nikon get their sensors from. If you are enlarging or shrinking a image it is important that you sharpen the new file.
For instance, you may wish to down size a full size file for an email or for web use, perhaps to 72dpi with 20cm being its longest side and eventually to a JPEG file at level 8. This file ends up around 130kb in size which is perfect for an email or the web. Before saving, you should sharpen the file. Only a small amount is required but it could make an important difference.
Your sharpening techniques can vary from subject to subject with one example being people photography. I don’t usually sharpen as much for portraits. You don’t want to highlight wrinkles and blemishes. You should also be careful not to over sharpen.
I have been using and teaching the same photographic principles since 1982. They include the correct method of how to stand, how to hold the camera, pressing the shutter release correctly and, as we have mentioned, the technical aspects of good glass and using the right lens for the job. It is not difficult to get this formula right. Once you have spent your hard earned money on the right equipment, then spend some time in your back yard or in the field and practice, practice, practice. You will quickly be capturing beautifully sharp results.
Darran Leal has been a regular feature writer for this magazine for several years. He undertakes photo workshops nationally and photo safaris internationally on a regular basis, helping thousands of photographers achieve better results. SafariWise is Australia’s only travel agency dedicated to photographers. Travelling - or you want more help on this feature?
Contact Darran today. Ph 07 5446 6538. Email julia@safariwise.com.au or jump onto www.safariwise.com.au.
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