Cheetah Picture Using Canon L-Series Lens

This picture of a young cheetah was taken in Botswana, using a Canon EOS 400D (Digital Rebel XTi)) camera plus Canon EF 100-400mm f/4.5-5.6L IS USM telephoto zoom lens at 320mm focal length. The shutter speed was 1/50 and aperture f/5.6, using aperture priority mode.

The Canon EF 100-400mm tele zoom is a useful lens for wildlife and sports photography because of its wide zoom range and image stabilizer. The main drawback of the lens is the fairly slow f/5.6 maximum aperture when used at the longer focal lengths. There has also been some criticism of the pull-push zoom mechanism, but most photographers who use the lens quickly adapt to this and don’t find it a hindrance.

This is one of Canon’s L-series lenses, easily identified by the red ring around the lens barrel. The “L” designation is generally taken to mean “luxury”, as these lenses are aimed at professional photographers who demand superior image and build quality and are prepared to pay premium prices.

To satisfy these demands, L lenses are made with special optical materials, including fluorite elements and UD (ultra-low dispersion) glass. They are also more ruggedly built than normal lenses, with extra weather sealing to keep out dust and moisture. To read a more in-depth article, see Canon L Lenses.

Canon SLR Lenses and Deciphering Lens Codes

There are more than 60 Canon SLR lenses available for Canon EOS single lens reflex cameras. This can be daunting for a beginner photographer trying to find the appropriate lens for a digital SLR like a Canon 450D.

This is a typical description for a Canon SLR lens: “Canon EF 70-200mm f/4L IS USM”. You’ll notice the various letters or codes in the description that need to be understood such as EF, L, IS, USM.

Here’s a brief rundown of Canon codes or designations:

1. “EF” designation

Canon introduced a new range of SLR lenses for its EOS 35mm film cameras around 1987. These “electro-focus” lenses had electronic mounts and replaced the existing range of FD lenses.

Today EF lenses remain the core of Canon’s lens lineup and can be used with older 35mm film cameras, top of the range full-frame digital SLRs like the Canon EOS 1Ds Mk III and entry-level cameras like the Digital Rebels (300D to 500D)

2. “EF-S” designation

Canon’s entry-level Digital Rebels and its prosumer 20D to 50D cameras have what’s called an APS-C format sensor which, at 22.5 x 15mm is smaller than a full-frame sensor (36 x 24mm).

The smaller sensor has the effect of cropping the image, known variously as “crop factor” or “lens magnification factor” and is similar to using a 1.6x converter. (See our previous post, Canon Digital SLR Crop Factor, for more on this).

While this is a bonus when using a telephoto lens — your 200mm lens now acts like a 320mm lens — it’s a disadvantage when shooting with wide angles. In the latter case, a really wide lens like a 24mm now becomes longer by 1.6x, so is like using a 38.4mm lens.

To counter the effect of crop factor on wide angle lenses, Canon introduced its EF-S lenses specifically for digital SLRs with APS-C format sensors. These carry the “EF-S” designation and cannot be used on EOS film cameras or on full-frame digital cameras.

3. “IS” designation

This stands for “image stabilization”, a technology aimed at reducing the camera shake that results in unsharp images. Each IS lens has its own image stabilizer unit, comprising a microcomputer and two vibration gyros, which detects lens movement and rectifies this.

4. “USM” designation

Stands for ultra sonic motor. USM technology, pioneered by Canon, uses sound waves to position the lens elements when focusing to produce highly responsive, fast and silent focusing with excellent holding torque.

5. “L” designation

Canon L lenses are designed for professional use, carry the “L” designation in the description, and have a red ring around the lens barrel to distinguish them from Canon’s normal lens lineup.

L lenses are made with special optical materials such as fluorite, ultra-dispersion (UD) or super UD elements to produce images that are sharp with superior color rendition and are also constructed to keep out dust and moisture..

6. “DO” designation

Stands for Diffractive Optics — an optical technology developed by Canon for building telephoto lenses that are significantly shorter and lighter than previously possible. Canon produce two DO lenses, the EF 70-300mm f/4.5-5.6 DO IS USM zoom lens and the EF 400mm f/4 DO IS USM telephoto lens.

For a more in-depth discussion about Canon lenses and what the various codes and designations mean, see this Squidoo lens: Canon SLR Lenses and All You Need to Know

Using a Canon Wide Angle Lens to Show Location

This picture of a Natal Francolin (Francolinus natalensis) pecking around for food was taken with a Canon wide angle lens — the EF-S 18-55mm f/3.5-5.6 IS zoom, fitted to a Canon EOS 450D SLR camera.

The camera was placed on the ground and the picture taken using an electronic cable release, so the viewpoint is almost eye-level with the subject.

Although wide angle lenses are not exactly the first choice for bird photographers, what this image shows is how a wide angle can give a much better idea of location and the surrounding vegetation than can a long tele lens with its shallow depth of field and narrow angle of view.

While it usually makes for a more pleasing image when the background’s totally blurred so the subject stands out from its surroundings, there are occasions when it’s necessary to show more of the background and surroundings and that’s when wide angles come into their own.

Exposure details: shutter speed 1/80 sec; aperture: f/5.6, ISO: 400, focal length: 21mm (33.6mm equivalent). See Canon EF-S lenses for explanation of why we refer to equivalent focal length.

Canon Digital SLR Crop Factor

Canon digital single lens reflex cameras do not all come with the same size digital sensor or chip.

On Canon full-frame digital SLRs such as the Canon 1Ds and 5D models, the sensor is the same size as a film negative - 36mm x 24mm.

On the Canon 1D models, the sensor is slightly smaller, measuring 28.5mm x 19mm (referred to as an APS-H sensor), while on the Canon Digital Rebels and 30D, 40D, and 50Ds, the sensor is even smaller, measuring 22.5mm x 15mm (referred to as an APS-C sensor).

Normally, with lenses designed for 35mm film cameras and digital SLR cameras, the image projected by the lens fully covers the area of the negative or full-frame sensor. However, when you substitute the sensor with one that’s smaller in area, part of the image flows over the edges of this smaller sensor. It’s like showing slides or an old home movie on a screen that’s too small, so the picture “overflows” the screen.

This can be seen in the example below, where the black lines represent a full-frame sensor, the blue lines an APS-H sensor, and the red lines an APS-C sensor:

The practical implications for photographers are far-reaching, as the image received by the smaller sensors is apparently now magnified - it fits on the full-frame sensor, but is too big for the smaller ones. The effect is similar to using a teleconverter - or post-processing by cropping the image in an image editor. This is great for photographers using long lenses, as their teles now have more reach, but it’s not so great if you shoot wide angle, as your wide angle lens is now more like a standard lens.

This effect on the image caused by smaller sensors is known as the “crop factor” or “focal length conversion factor” - for more information, see this article about the Canon Digital SLR Crop Factor.

For general information about Canon lenses, see these articles:
Canon Telephoto Lenses
Canon Zoom Lenses
Canon Wide Angle Lens

Self-Catering Cottage for Trout Fishing Enthusiasts

For trout fishing enthusiasts living or holidaying in South Africa, Excelsior Self-Catering Cottage in the picturesque Midlands of KwaZulu-Natal could just be the answer.

The cottage, which can sleep up to eight, is situated in rolling farmland in the heart of Natal’s Midlands Meander, 19km from the village of Nottingham Road.

Chief attraction for many is the excellent trout fishing. Guests have at their disposal two large, well-stocked trout dams (used for fishing competitions). When the cottage is occupied the dams are reserved exclusively for guests and fishing is on a “catch and release” basis. Below is one of the dams:

If you’re looking for a relaxing break in the country, staying in a Natal Midlands self-catering cottage, you won’t find better value than this.

New Photography Blog

Photographer Scotch Macaskill has started a new blog where he’ll be posting a variety of images, including his favorites and also experimental work, particularly those using slow shutter speeds to create motion blur, and also those using digital manipulation to give a “painterly” look (as in the MG photo below).

MG TD, a British Classic Sports Car

The blog has only just been created so there’s not yet much content, but if you’re interested in photography, then it’s worth bookmarking for future reference, or subscribing to the RSS feed. Find out more by visiting Scotch Macaskill’s Blog.

Bicycle Posters Remain a Popular Art Form

The bicycle, having played a pivotal role in society during the last century,  has for many years been a popular subject for artists and photographers. This has resulted in a wonderfully diverse selection of cycling posters and vintage bicycle posters, in the form of art reproductions (as in the examples below), becoming accessible to those for whom originals or limited-edition prints are simply too expensive.

Buy at AllPosters.com

Buy at AllPosters.com

Read more ….

Hiking Gear Customer Reviews

Customer reviews of hiking gear, provided by real people who’ve actually bought and used the gear, are a valuable source of information that can help when choosing new hiking equipment.

At least postenial customers can be pretty sure the review is unbiased and is not simply an advertisement posing as a supposedly neutral write-up.  Today people like to share information and help others, which is the only logical explanation why customers are happy to write reviews, not only of their shopping experience, but also of how the product itself measures up.

The Hiking Basics website not only features hundreds of keenly-priced hiking products that can be purchased online, but also has a custom hiking store where, for each product, the emphasis is on unbiased customer reviews, providing both positive and negative feedback on a range of hiking products, from backpacks to cookware.  For more, see:

Hiking Backpacks Customer Reviews

Hiking Sleeping Bags Customer Reviews

Walking Poles Customer Reviews

First Aid and Safety Customer Reviews

Camping Cookware Customer Reviews

Success Did Not Come Overnight for Artist Jack Vettriano

Jack Vettriano (birth name Jack Hoggan) was born in Fife, Scotland in 1951. But unlike many gifted artists who start painting while very young, Vettriano only began teaching himself to paint after a girlfriend gave him a set of watercolor paints for his 21st birthday.

In 1989, at the age of 38, he felt ready to display his paintings in public and submitted two works to the Royal Scottish Academy’s annual exhibition. Both were accepted and sold immediately, after which the artist was approached by several galleries keen sell his work.

In 2004 The Singing Butler, Vettriano’s best known painting, was sold at Sotheby’s for close to £750,000. In the same year he was awarded an OBE for Services to the Visual Arts.

Although his work is often disparaged by art critics as lacking in imagination, Vettriano is one of the most commercially successful living artists. While his original paintings regularly fetch six figure prices,  it is rumored he earns more from the sale of reproductions.

And that’s fortunate for art enthusiasts who enjoy his work as Jack Vettriano Prints are now readily available and affordable for those who can’t afford to pay out huge sumes of cash for originals.

See the rest of the article about Jack Vettriano the artist .

Setting up your Home Office

It’s tempting when setting up a home office to make do with office equipment and furniture that you already own. This reduces start-up costs and makes sense in many ways. But you’ll soon find the old, rickety desk and plastic chair that you start off with is draining your productivity, specially after long hours in your new “office”.

Similarly, the three-year-old computer that’s been used for everything from emails to downloading music and digital photographs will seem adequate initially, but will also start frustrating you as the business grows and you need to increase efficiency.

So, before too long it’ll become clear that there are valid reasons to upgrade your office furniture and equipment. Spending money on these items is not an indulgence, but a necessary business cost to ensure you become as productive as possible.

Find out more about this topic by reading the article Office Equipment - Essential Tips on Outfitting a Home Business on the Internet for Business website that also explores the benefits of the internet for business.