74

A picture is worth a thousand words, here. This is a Twin Lens Reflex camera: The two lenses are linked together so they focus as a set (either the whole front panel moves, or the lenses are linked by gears so that they turn together to focus). The top lens — the "viewing lens" — has a mirror which bounces the view to the ground-glass viewfinder. The bottom ...


71

Uncle Bob is not actually your Uncle Bob. Uncle Bob is the derogatory term used by professional and semi professional photographers to describe a 'man with a camera' and occasionly someone with 'all the gear, no idea'. There isn't a clear definition of Uncle Bob, and he can be found in many guises, this is my experience so feel free to mix and match: Not ...


60

I actually just shot a photo just like this. This was shot around mid afternoon in downtown Portland and I assure you, there actually was traffic moving along the bridge. The set up included stacking an 18 stop ND filter on top of a polarizer and exposing the frame for 11 minutes, ish (707 seconds to be exact). As long as the people or cars keep moving, at ...


55

STM stands for Stepper Motor and is a applied to a new range of Canon lenses which feature a new design of focus motors which, along with a new iris mechanism are designed to eliminate (auditory) noise during video recording. Canon haven't revealed any information about how the new design works but it's probably the same type of motor used in mirrorless ...


54

Single lens means that there is only one lens attached to the camera at once. This is to distinguish it from a twin-lens reflex camera, which has two lenses - one used for the viewfinder and one used for actually taking the photo.


45

DCIM is short for Digital Camera IMages and is part of the industry standard outlined by the Design rule for Camera File system. This standard was adopted as the de facto standard for storing digital image and sound files in memory devices by the digital camera industry to insure interoperability from one brand to the next. From wikipedia: Design rule ...


43

I will only answer the first question: What are frequencies in images? Fourier Transform is a mathematical technique where the same image information is represented not for each pixel separately but rather for each frequency. Think about it this way. The sea has waves some of which are very slow moving (like tides), others are medium in size and still some ...


41

One straightforward way to achieve this effect is to take multiple shots of the same scene and combine them using median blending. This technique is commonly used for noise reduction, and does it very effectively — so effectively, in fact, that it can even hide "noise" such as random people walking through the scene. What median blending effectively ...


41

"GAS" is a joking acronym for "Gear Acquisition Syndrome" — basically, a hobby that is adjacent to photography. See also "Lens Acquisition Syndrome" and similar. It means buying new equipment for its own sake, and a drive to keep doing so, probably with an ever-increasing budget. I don't think it's necessary bad. There can be something fun about following ...


39

It means the lens focal length doesn't change, but you can change the framing by moving your feet — which in this idiom are wearing sneakers (which, for non-native English speakers, are casual athletic shoes). I've more commonly heard "zoom with your feet", which is the same thing except not dependent on shoe style. It important to be aware that changing ...


36

F-stops are purely geometrical, the ratio of aperture to focal length, regardless of actual light transmitted. But all lenses absorb a part of the light passing through them, and the amount being absorbed varies lens to lens. So, in situations where even the slightest change of lights being transmitted affect the output, i.e cinematography, where many images ...


36

This is a Sigma name for one of their lens lines. It is not a general purpose term and really only has the marketing meaning Sigma ascribes to it. From the Sigma website, that definition is: Engineered for today’s photographer who wants to do it all, our Contemporary line combines superior optical performance and compactness for high-performance lenses ...


35

What's a nifty-fifty? It's a budget level 50mm prime lens. Pretty much all of the various camera makers offer one. There are several reasons that make them so nifty. Price - They're some of the most inexpensive prime lenses¹ available for most systems. Performance - They can compete optically at 50mm with zoom lenses costing much more. Maximum aperture - ...


33

USM - Ultrasonic motor (This is the Canon Terminology) This is a big improvement over older micro-motor based autofocus systems, which are significantly slower and louder. There are two types of USM systems "Micro" and "Ring". The preferred type is "Ring Type" which always allows for manual focus without turning off auto-focus. Most, but not all, Micro USM ...


31

These letters refers to zooming depth as follows, W = Wide angle T = Telephoto Read more about wideangle and telephoto in the tags.


30

In the context of a shoot, Uncle Bob is usually a very affluent gent (or has enough money to spend on some prosumer or pro gear) whose photography knowledge is usually at amateur levels, whose company was asked for by the event attendees, but whose photography was not. He has a habit of wanting to "talk shop" with the photographers who are being paid to ...


29

Exposure fusion is a process that takes multiple images and combines them to create a single image while only keeping the properly exposed elements. In contrast to HDR images, exposure fusion is more basic, gives a more realistic effect, and requires fewer steps. The exposure fusion(fusion, or EF) process takes each individual pixel and assigns a weight to ...


27

An F-stop indicates how much light the lens could theoretically transmit - focal length divided by diameter of aperture. In practice, there are some losses each time a light ray enters or exits a glass surface. In a lens with many elements, these losses may sum into a considerable amount (like 25% loss in some old zoom lenses). This, naturally, affects ...


26

To elaborate on my earlier comment: One option (besides the photoshop one mentioned in comment by @Max) is using heavy ND filtration. This picture is a busy landmark in Prague, shot with a +10 ND filter. The total exposure time was two minutes. You can just about see people where they stopped for a while (these are tourists, so they most likely consulted ...


24

Fundamentally a telephoto design is used to make a lens body shorter than it's focal length, for practical reasons [what if your 18-300 ultrazoom was actually 30cm long?], a retrofocus design is the opposite, and makes a lens longer  than it's focal length in order to leave space for the mirror on an SLR. You can tell if your lens is a retrofocus or ...


23

Wikipedia page: Lomography Lomography was a fad from some time ago which involved using cheap, old Russian film cameras, primarily a camera called the LOMO LC-A, to create pictures with a poor technical quality. The term is a trademark of Lomographische AG, an Austrian company who now manufacture that and a range of other cheap plastic cameras for sale in ...


23

Firstly, distance is used for focal length because it measures the distance between the plane of the lens and the point at which refracted rays meet at a point, when the incident rays were parallel. Below is a simple diagram of a single lens. Note: This is only for convex lenses. The use of millimetres is simply because it is a scale appropriate for this ...


23

Look at your own shadow. If you can't find your shadow then the light is as soft as it possibly can be. If you have a hard edged shadow then the light is hard. If you can make out your shadow but it's faint or the edges are not defined then you have somewhere in between (which can often give the best results).


21

The term "exposure" is used for a number of different but related things in photography. I can see how this might be confusing. Here are six different ways in which it is used: The combination of all factors which make a photograph have a certain overall brightness. The key factors are shutter speed, lens aperture, and sensor or film sensitivity (a.k.a. ISO)...


21

Let's try this as a very different explanation: Imagine that you have been asked to record a piano recital at the local school. It will occur in the auditorium, and it will be full of parents and friends to hear the work of the pianists. You are not a studio technician, but are doing this as a favor to a friend. You bring your laptop, and you have an old ...


21

You are correct that the term "macro" means large scale (e.g. macroeconomics), however its use in photography is relative to microphotography, that is imaging using microscopes. The tradition definition of a macro lens is one that can achieve a 1:1 magnification, which means the image projected onto the recording medium is life size. So for a common APS-C ...


20

You are correct, a DSLR can have a fixed lens and there actually was, the Olympus E-10 for example. My guess is that there is little advantage to a fixed in a DSLR and obviously flexibility is lost, not to mention the high-cost of a large sensor which makes one want to reuse it with various lenses. The DSLR's mirror and pentaprism/pentamirror force the ...


19

Not all photography is art, not because of some failure, but because it never meant to be that. Some documentary photography may be art, but most isn't. Some of it is just recording a moment. Most photography is decoration, or otherwise functional, not meant to be art, let alone upper-case-a Ahhrt, or Fine Art. "What is art?" is a constant question — in ...


19

About a million. I think that in general due to rounding — and more importantly, other real world factors which mean that megapixels only relate loosely to actual resolving power — it doesn't really matter if "megapixels" is binary or decimal. It is a useful term because it happens to be in the range where we get human-useful small numbers with the digital ...


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