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Lens Camera Guide

Posted by [email protected] on May 5, 2016 at 1:20 AM Comments comments (520)

How to find the right target ?

 

The ability to change lenses is one of the main advantages of digital SLR cameras and hybrids. The user adapts according to the cliché that it wants to achieve . This apparent flexibility is not without its counterpart : the objectives are bulky and expensive. Our advice to choose well.

 

SLRs and hybrid devices are often delivered in kit with a versatile lens that will suit most users . But once the photographer develops specific needs ( wildlife photography , sports , portrait, etc. ), it must adapt its equipment with the proper lens.

 

 

 

Focal length and aperture

A target is characterized by its focal length and aperture. The focal length , in millimeters, determined the scope of the objective associated with a given sensor . The opening reflects its brightness, that is to say the amount of light entering the lens. It is indicated by numbers placed behind an "f" on the lens (f / 1, f / 1.4 , f / 2, f / 2.8 , etc.). The opening decreases as the number increases . It also determines the depth of field ( sharpness of the picture area).

 

Equivalent focal length

The angle covered field depends on the focal length , that is to say the distance from the camera 's sensor of lens optical center. But it also depends on the size of the camera sensor. All film cameras operated with a 35 mm film (24 × 36 mm). But in digital, the sensor size is not standard . The manufacturer of a goal does not know in advance the size of the camera sensor on which it will be used . For the user mark, it indicates the focal length 24 × 36. Each unit has a coefficient by which multiply the focal length to obtain the equivalent focal length. It is 2 in Olympus and Panasonic, Canon 1.6 , 1.5 , Nikon , Sony and Pentax . Thus a 50 mm on a digital Nikon or Pentax he will fit as a 75mm on a film

The major targets families

A standard lens is the angle of human vision; its focal length (equivalent to 24 × 36 mm) is 50 or 55 mm. It is suitable for a "family" use (holiday photos, group, etc.).

A telephoto lens has by definition a long focal length (85 mm, 135 mm, 200 mm and more). The longer the focal increases, so the scope of the objective is restricted and reduced the captured area. It corresponds to a viewing angle of less than the human eye. this type of lens is used for taking distant details or portraits.

Conversely, a wide angle lens of short focal length (less than 30 mm). It can cover wide viewing angles, and is therefore well suited to shooting landscapes. Some lenses allow to photograph 180 °; it is the fisheye ( "fish eye") whose focal length is generally 15 or 16 mm, sometimes less.

Finally, macro lenses allow to photograph closely tiny subjects (flowers, insects, etc.).

 

Fixed focus and zoom

fixed focal objectives offer no magnification. The photographer must move away from or closer to the subject to change the captured area.

 

Zoom lenses allow the student to vary the focal length on a specific range (18-200mm, 70-300mm, etc.). They are more versatile.

 

Mount

The objectives of a trademark is generally not compatible with devices of another: each manufacturer offers its own beast. Nikon zoom can not be attached to a Canon camera, etc. However, there are some cases in which the rings can therefore be adapted. But they prevent the operation of some automations like auto focus.

 

Some manufacturers such as Sigma or Tamron, propose objectives compatible with devices from different manufacturers.

 

Focusing Distance

All lenses provide the minimum distance that must be a subject to be able to update it. This distance varies from one objective to another, from a few centimeters to several meters for large telephoto lenses.

 

Weight / size

A fixed lens 50 mm weighs about 300 grams, the weight of a telephoto lens can easily reach several kilos. Both say, a goal does not know how to forget. Once the photographer is using dedicated objectives, it is forced to carry heavy equipment. He will also stay in suitable bags (with protective reinforcements) expensive.


Hybrid Digital Cameras Guide

Posted by [email protected] on May 5, 2016 at 1:15 AM Comments comments (0)

 

The choice of the lens on a compact

Halfway between compact and SLR, not quite either of the bridges, "hybrids" are the latest development in digital cameras. They have been specially designed for those looking for a quality close to that of reflex associated with compact maneuverability . After sluggish start , they now face a real success.

Hybrid combine the advantages of both technologies. Thanks to their housing similar to those of compact cameras, they have a space and weight limitations. But as the SLR, they offer the ability to change lenses to get a good picture quality and the ability to adapt shooting each situation. Finally, the hybrid models are particularly aimed at lovers of beautiful photos that do not want too much clutter.

 

More or less compact models

All members of the family of hybrids are not alike. Some manufacturers seek above all to make their devices as compact as possible. But in this case, certain elements may be sacrificed, as the viewfinder. Others play more on the similarity with reflex. They are usually a little more impressive. In each choice.

 

The image quality at the rendezvous

With their hybrids, manufacturers promise a similar image quality to that of SLR, thanks to components of good quality and large size sensors. The models we have tested to date attest: the picture quality is overall at the rendezvous. Images are generally sharp and bright and most hybrid of performance does not blush to those of some reflex. In video mode, the hybrids seem to be as good as SLR cameras (laboratory results are comparable), at least when lighting conditions are good. In low light, the hybrid may experience a bit more difficult. Finally, usability side, nothing to say. If hybrids all have powerful automatic modes, they also offer easy access to many manual settings.

With or without Viewfinder?

Considered by some as a handicap, the electronic viewfinder has a big advantage: it helps to have a pretty good idea of ​​the layout according to the settings before taking the picture, which does not allow a reflex sight. In addition, manufacturers have improved the definition and limited the lag effect making it difficult framing moving subjects. Our tests show that finally trigger times are generally shorter when the framing is done through the viewfinder than the screen (Live View mode). However, it remains less precise than the optical viewfinder to own reflex, and for reasons of size or price, some hybrids prefer to make or propose the optional (180 € Sony, Panasonic € 200 for example).

 

Connectivity galore

NFC, Wi-Fi, Bluetooth ... hybrids are all hyper-connected. With these wireless link protocols, can usually send your photos by email or on social networks directly from the camera, or connect the camera to a smartphone in order to change settings or run from triggering an app. Not essential, but frankly practice. however be careful because all connected cameras do not offer the same services or even the ergonomics.

 

A wide range of objectives

fixed focal length, telephoto, wide angle ... manufacturers now offer a wide optical range for all situations. They have even developed motorized zoom, integrated optical stabilization, designed optical brighter ... In addition, like the housings, optical hybrids are more compact and lighter than the SLR.

 

You already have SLR goals? By default, they are inconsistent with the hybrid models. Indeed, the appliances mounts differ from brand to brand and from a family of aircraft to another. To keep their customers, manufacturers have however developed rings that allow new mounts adapt to old objectives. Just find the right jungle manufacturers and formats. The problem of these rings is that they are expensive and do not always retain some features (AF or zoom motor, for example, are sometimes unavailable). Above all, the objectives of SLR cameras are much larger and heavier than those designed specifically for hybrids. This solution is not viable in the long term.

 

A price which is not compact

One downside: the price of these devices. Be equipped with a hybrid expensive, between 500 and € 1,300. What wonder whether it is not better to buy a good compact wide zoom range (a bigger zoom), for which a budget of € 300 is enough, or a true SLR, even entry. Especially since, if they come with an optical "boilerplate" (14-42 mm or 18-55 mm), hybrids, to be used fully, must be accompanied by complementary objectives. The costs are far from negligible: from 300 to € 1,300 each!



Digital Cameras Bridge Guide

Posted by [email protected] on May 5, 2016 at 1:10 AM Comments comments (0)

Between compact and SLR

 

Halfway between compact and SLR cameras, both in terms of budget performance , bridges targeting a public amateurs . Affordable but quite bulky , they offer great freedom of settings and especially powerful zooms.

The bridge ( "Bridge" in English) is a kind of intermediary between compact and SLR camera. This positioning also places the competition with the two families, in terms of price as performance. An entry bridge is not worth not necessarily better than a high-end compact; first prize reflex, not necessarily more than a quality bridge. To describe in one word this ambivalent device, say that this is a robust digital camera (but bulky), with a powerful zoom (but an immovable object) and an electronic viewfinder ( reliable).

 

With their complete housing, bridges offer ergonomics beyond comparison with the compact. The grip is usually much better; fingers are positioned naturally and can operate without contortion and many different orders. Consideration of this comfort: the device is quite heavy and bulky. But this space is also justified by the wealth of settings and modes. The user has the hand in many settings: aperture, shutter speed, white balance, focus, etc. It can also hide behind an automatic mode if desired.

 

 

The bridge ( "Bridge" in English) is a kind of intermediary between compact and SLR camera. This positioning also places the competition with the two families, in terms of price as performance. An entry bridge is not worth not necessarily better than a high-end compact; first prize reflex, not necessarily more than a quality bridge. To describe in one word this ambivalent device, say that this is a robust digital camera (but bulky), with a powerful zoom (but an immovable object) and an electronic viewfinder ( reliable).

 

With their complete housing, bridges offer ergonomics beyond comparison with the compact. The grip is usually much better; fingers are positioned naturally and can operate without contortion and many different orders. Consideration of this comfort: the device is quite heavy and bulky. But this space is also justified by the wealth of settings and modes. The user has the hand in many settings: aperture, shutter speed, white balance, focus, etc. It can also hide behind an automatic mode if desired.

 

An immovable object

The objective contributes to the overall size of the apparatus. Its long focal ranges happily play in his favor. It is even one of the main advantages of this type of device: a bridge is very versatile, it can take photos of all types (family, large areas, groups, portraits, sports ...) with satisfactory quality. Attention however to the minimum focal length, which should be around 28 mm to provide a true wide angle (and thus permit to photograph a wide field, such as a landscape or a group of people in a small room where the photographer lack of perspective). Zoom, magnification, then intervenes. On a bridge, it can go up to 40 ×! Ideal for taking pictures from afar.

A bridge lens is designed to provide good performance over the entire length of the zoom range . One reason for this : it is not interchangeable . That is, with its viewfinder ( see box ) , which characterizes this type of device 1. The most demanding users will connect lens adapters ( between 50 and 400 € ) to stretch the bounds of the focal range in the two extremes. A "real" stabilizer, optical or mechanical (not digital, see box ) is essential to minimize blur , including maximum zoom.

Widescreen

Over the screen, the easier the shot. But beyond the size it must consider its resolution, contrast and its ability to limit the occurrence of glare. Furthermore, prefer the multi vertically and horizontally. So you can use in all circumstances.

 

A sensor to the height

The resolution of the sensor is no longer a decisive criterion of choice: she now reached sufficient levels largely for everyday use. The average is 12 to 18 Mpixels, allowing among others to print pictures without the problem at size 21 × 29.7 cm or larger in maximum quality or crop your photos from a computer if necessary.

 

Increased sensitivity

Look at the different values ​​that can be assigned to sensitivity. This determines the relative aperture / shutter speed for a given illumination; it is measured in ISO. The user can choose between different values: 100, 200, 400, 800 and up to 1600 in most cases. Some devices allow you to go into greater sensitivities (3200, ISO 6400 or more) for shooting in dark environments. But mistrust: the quality is rarely optimal, high sensitivities are highly generating "noise" that is to say of parasites affecting rendering. In photography, there was talk of "grain" to describe this phenomenon.

 

Useful features

Flash. It is useful to replace the built-in flash, generally less efficient (power, uniformity). Check in this case that the device is provided with a claw able to accommodate.

 

Burst mode. To take pictures of moving subjects at sporting events such as shooting multiple images at file automatically multiplies the chances of a successful shot. Burst mode is measured in frames per second, it is generally around 2 or 3. Some devices offer more up to 8 frames per second, but not in full resolution.

 

RAW format. Photographers will also enjoy record images in RAW, gross recording format that multiplies the possibilities of editing (white balance, exposure ...) before recording the snapshot in a readable format (eg .jpg) to exploitation. This method provides more flexibility in changing shooting settings, look better, and the ability to save the selected settings (on the computer) to apply to multiple images (batch processing). The consideration: RAW files are very large, which requires the use of high capacity memory cards.

 

Batteries or battery , choose

The battery supply limits the risk of ending up short of energy , especially on long trips , but it can be expensive to use. When the device is powered by a battery , a second copy can be useful not to run out . Allow between 30 and 85 € ( depending on the brand and model ) for a battery and so , almost, for an extra charger . Some bridges are supplied with a CR-V3 battery , which can be replaced by two LR6 batteries or rechargeable batteries .



Digital SLR Cameras Guides

Posted by [email protected] on May 5, 2016 at 1:10 AM Comments comments (0)

The SLR is the most advanced digital cameras , but also the most expensive. Seasoned professionals and amateurs are turning to this high-end equipment to satisfy their need for total control of photographic settings.

The SLR is a digital camera designed not just to take pictures, but to make the picture a hobby (or profession) as such. On this type of device, the manual settings (aperture, shutter speed, sensitivity, white balance, focus, etc.) play for much of the rendering quality. We must master to perfection to take full advantage of its device. Here is a small development to guide you if you decided to take the plunge. And thus join the world of photography enthusiasts.

 

The sensor, an essential component

As with any digital camera (compact, bridge, hybrid), the sensor resolution among the first criteria put forward by the manufacturers. This is however not the most decisive: the average for an SLR is now around 20 megapixels, which is already huge. Knowing that to obtain a quality image for printing, the pixel density is to achieve 300 dpi (dots per inch) minimum, and a sensor 6 Megapixels suffices to print an image of 18 × 24 cm. However, a higher resolution can be useful for bigger enlargements or to crop the image on his computer.

 

On an SLR, this expensive component manufacture is on average four times greater than on a CD, or on a bridge. The most common format is called APS-C, which is approximately 15 × 23 mm. Only high-end devices are equipped with larger sensors, the "historic" dimensions of 24 × 36 mm. There is talk of sensors "full frame" (FF) or "full size." It includes consideration of sensor format if child from film, you already have your goals (see box).

 

Budget: tick on optics

An interchangeable lens

As their ancestors silver, objectives are interchangeable on a DSLR. It's one of the advantages of these devices, but it is also where lies their main weakness: sensitivity to dust. When changing the lens, the sensor is exposed. The slightest collect dirt appears on the pictures! The handling must be carried out in a clean environment. Some models incorporate a function to clean the sensor when power is turned off.

 

It is commercially sold alone housings (count from 300 to over € 3,000) or with a basic objective of average quality (even among major manufacturers). Opt immediately for a better objective may be appropriate, even if it costs more. Much being aware, optics represent anyway a large budget for any DSLR user. To cover the same focal range as a bridge, for example, it will buy two or three goals at minimum! Supply is abundant. From the ultra-wide angle to telephoto, for photographing large areas or microscopic insects, we find on the market a range of fixed targets or offering varied focal ranges. Their prices range mostly between 100 and € 1,000! The choice will be primarily driven by the needs and requirements of the photographer.

 

Stabilization: housing or objective?

Canon telephoto

The other drawback of SLR is their weight. It is not uncommon that the housing assembly + objective exceeds the kilo. Unless you use a foot, difficult in these conditions to remain perfectly still during shooting. To compensate for movement by the photographer, and thus prevent the photos from blurring, manufacturers have integrated stabilization systems. Two schools of thought. Canon and Nikon have chosen to equip their goals, believing that each of them had to be stabilized differently depending on its intrinsic parameters (focal length, weight). Other brands (Olympus, Pentax, etc.) opted for a stabilization of the housing itself (its sensor, specifically) in order to save money (a stabilized lens costs on average 25% more expensive). At each to make his choice.

 

Other checkpoints

ISO mode

Sensitivity: It determines the relative aperture / shutter speed for a given illumination; it is measured in ISO. The user can choose between different values: 100, 200, 400, 800 and up to 1600 in most cases. Some devices allow you to go to even greater sensitivities (3200, ISO 6400 or even more!) For shooting in dark environments. But mistrust: the quality is rarely optimal, high sensitivities are highly generating "noise" that is to say of parasites that affect the rendering. In photography, there was talk of "grain" to describe this phenomenon.

Different extra flashes

Flash: A supplementary flash can also be useful (allow 50 to € 600 on average). Certainly, it is in addition to other accessories (and more so, optical and must carry bag, which is also a budget, between 20 and 300 € depending on size and quality). But it will replace the built-in flash, generally less efficient (power, uniformity).

Burst Mode: To take pictures of moving subjects at sporting events such as the file photograph multiple images automatically multiplies the chances of a successful shot. Burst mode allows usually take 2 to 4 fps keeping your finger on the trigger. Some devices offer more (up to 8 frames per second), but the resolution of each image is greatly diminished.

 

RAW: Photographers will appreciate the ability to save the images in RAW, a raw recording format that multiplies the possibilities of editing (white balance, exposure ...) before recording the picture in a format (.jpg, by example) to operate. This method provides more flexibility in changing shooting settings, look better, and the ability to save the selected settings (on the computer) to apply to multiple images (batch processing). The consideration: RAW files are very large, which requires the use of high capacity memory cards.

 

Power Type (or batteries): The SLR cameras are powered by Li-ion batteries. Their autonomy allows taking pictures at least 250. A second battery, take-charge, can be very convenient to not run out. Allow between 30 and 85 € (depending on the brand and model) for a battery.





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