Focal Length and F-Stop Explanation Lens Focal Length What is Focal Length, anyway? Very simply, it is the distance from the lens to the film, when focused on a subject at infinity. In other words, focal length equals image distance for a far subject. To focus on something closer than infinity, the lens is moved farther away from the film. This is why most lenses get longer when you turn the focusing ring. This means a 400mm lens should be 400mm long. What is F-Stop, anyway? F-stop is the focal length divided by the diameter of the lens. Where do those numbers come from? For a further explanation of f-stops, try this. Lens Focal Length Chart Taking the nature photographs like those in my books about Rocky Mountain National Park, Wildflowers and Wildlife require an assortment of lenses depending on the subject. "I want to take a bluebird picture. As you can see, even a relatively huge 600mm lens at the relatively close distance of 20 feet doesn't give the huge magnification you might expect. Home © Copyright David Dahms
Field of View Crop Factor (Focal Length Multiplier) With the advent of Digital SLR Camera Bodies, the term Field of View Crop Factor has come into our world. The source of this term is the smaller-than-35mm sensor present in many of Canon and other manufacturers' DSLR sensors. Canon's EF Lenses still focus the image on the same plane as before, but sensors smaller than 35mm sensors do not capture the entire image. Thus, the image is "cropped". The Field of View Crop Factor (FOVCF from here on) refers to the amount of the image that is cropped. Here is a diagram illustrating the size differences between Canon's currently available DSLR sensors (I personally don't expect to see any new sizes introduced by Canon in the near future). The above image lists the FOVCF and the approximate size of the sensors. When looking through the viewfinder on Canon's DSLR cameras, the sensor size is immediately obvious as the viewfinder size generally reflects the sensor size. I'll say it again - the subject framing is significantly different.
Portraits with Two Lights: Adding a Fill Light A second light source — usually called a fill light or fill flash — can greatly improve portrait lighting. It reduces the depth of shadows and softens the appearance of facial features, amongst other traits. Best of all, a fill light is easy to create: either a simple on-camera flash or a reflector is often sufficient. However, a second light source can just as easily harm portraits. Harsh Overhead Sunlight Sunlight with a Fill Flash If you haven't done so already, also take a look at the first part of this tutorial:Introduction to Portrait Lighting: One Light Source With a single light source, the most important considerations were its direction and apparent size. note: diagrams show the effect of a fill light, not necessarily its ideal position (more on this later) Perhaps the most common lighting scenario is to use an on-camera flash as the fill light, and sunlight as the main light. Portraiture typically appears better with a flash ratio near 1:2. Natural Fill Lighting. Reflectors.
Learning about Exposure – The Exposure Triangle A Post By: Darren Rowse Bryan Peterson has written a book titled Understanding Exposure which is a highly recommended read if you’re wanting to venture out of the Auto mode on your digital camera and experiment with it’s manual settings. In it Bryan illustrates the three main elements that need to be considered when playing around with exposure by calling them ‘the exposure triangle’. Each of the three aspects of the triangle relate to light and how it enters and interacts with the camera. The three elements are: ISO – the measure of a digital camera sensor’s sensitivity to lightAperture – the size of the opening in the lens when a picture is takenShutter Speed – the amount of time that the shutter is open It is at the intersection of these three elements that an image’s exposure is worked out. Most importantly – a change in one of the elements will impact the others. 3 Metaphors for understanding the digital photography exposure triangle: The Window Aperture is the size of the window.
Crop factor and interchangeable lens cameras Understanding focal length multipliers, often referred to as crop factor, seems confusing at first. It doesn’t have to be. But it’s important to get the gist of it before buying lenses for an interchangeable lens camera with a crop factor. As an example, a 50mm lens on DSLR with a focal length multiplier (FLM) effectively becomes mid-telephoto. To calculate the effective focal length of a lens, the focal length multiplier of the camera must be used. Canon’s entry level camera’s multiplier is usually 1.6. A 50mm interchangeable lens on a digital camera with a 1.5 multiplier would have an effective focal length of 75mm. Full frame DSLRs do not have multipliers or, more correctly, they have a multiplier of one. Wide angle shots and focal length multiplier If you take a lot of wide angle shots, lenses like the popular 28mm wide angle lens will no longer give a wide angle of view. Shutter speed, camera shake and FLM However, this rule needs to be adjusted when using a DSLR with a crop factor.
Bernie’s Better Guide to Depth of Field for Geeks Who Want to be Digital Artists | Bernie Sumption :: Photography Being a guide to portrait photography cleverly masquerading as a technical analysis Like the topics we covered in the beginner's guide last month, depth of field might initially seem complex, but behind it is some relatively simple logic and maths. Don't worry if maths isn't your strong point: long equations are the crutch of the inarticulate, and there's nothing in this article more complicated than division. Speaking of division, I like to divide photography into two broad disciplines. The following image depicts a (fake) flower about 50cm away, with a hedge around 5 meters behind it. A photo taken at wide aperture A photo taken at narrow aperture Depth of field The range of distances in a photo within which the image appears sharp. Blur The size of the blur discs as measured in the real world. Circles of confusion The size of the blur as measured on the photographic image. Blur vs circles of confusion: Consider the rightmost petal and the leaves in the bottom right. Onwards... An example 1.
Cactus 4-Channel Wireless Flash Trigger Set V2s CACTUS Wireless Flash Trigger V2s set now includes the flash stand you’ve been longing for. It’s FREE! Three components are included in this trigger unit, a transmitter, receiver and a flash stand. The transmitter is to be attached on the hot shoe of the camera while the receiver is to be attached to external flash. This trigger set comes with a smooth and slim designed flash stand made of ABS+PC material (rigid & durable). This wireless slave flash trigger unit triggers other flash units when the transmitter is activated. With the wireless flash trigger, you can place the flash at different angles and distances from the object. The transmitter emits radio signal to the receiver when shutter is pressed. This flash trigger unit has strong anti-interference function and has four channels for you to choose. This unit can be triggered continuously for 20,000 times. Since the new version runs on different channels, it can only work with V2/V2s receivers and not the previous version.
Photography | Photo Editor | Photography Tips – FroKnowsPhoto.com What do numbers letters on digital camera lens mean (Website Design Tips) What do all the numbers and letters on a digital camera lens refer to and what do they mean? If your new to DSLR photography the first things you'll need to know when buying a new lens will be concerning the numbers and letters printed on the lens. You will need to know what they mean to ensure you buy the lens that suits your specific needs. First I'll start explaining what the mm number means. For example on a Canon EF-S 17-85mm f/4-5.6 lens you will see the number 17-85mm written on the side. For example, the smaller the mm number the wider the angle of view within a photograph. On the other end of the scale, big mm numbers like 200mm or 300mm provide a magnified telephoto view. The difference between a lens that has a single mm number to one that has two mm numbers. If a lens has a single mm number, for example 100mm written on it, it is said to be a prime lens. If a lens has two mm numbers on it, for example 17-85mm, this tells you it is a zoom lens. What does the ratio number mean?
Sekonic 401500 Prodigi Color C-500 Photographic Meter 401-500 The Sekonic PRODIGI COLOR C-500 is the world's only photographic color meter designed to read spectral sensitivity of both color film and CCD and CMOS sensors used in modern digital still and DV cine cameras. Serious photographers and cinematographers know that good lighting and proper exposure are more important now than ever. With the higher demands of today's digital medium, "garbage in" can mean hours of postproduction. Crop Factor (Focal Length Multiplier) The Crop Factor is a term that can be heard quite often in the world of digital photography. What does it mean that a camera has a crop factor of 1.6x and how does it affect your focal length? We try to untangle this issue and describe it as clearly as possible. The subject of crop factors and focal length multiplier can be a bit confusing and hard to understand at first — I will try to explain it as simple as possible but yet informative enough for you to get the entire picture. The size of the sensor is what controls the crop factor, and it’s always compared to a 35mm film size. As you can see in the illustration above, a body with a crop factor captures only the center part of the image. It’s important to know that the crop factor changes the field of view, it doesn’t actually change the focal length, since that is something that is decided by the design of the lens. Lenses designed for Crop Factor cameras Here is a list of the name camera manufacturers call their digital only lenses.
Weather Photography: lightning, clouds, atmospheric optics & astronomy