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Tag Archives: Autofocus

Digital Photography Glossary

The DP Review site has an excellent glossary section where all those words you use on a daily basis as a keen photographer  which slide from your tongue as if their understanding were universal reside. Sections include: Digital Imaging; Camera Systems; Exposure etc

Here is just one of the numerous sections covered

Here is the entry on autofocus

All digital cameras come with autofocus (AF). In autofocus mode the camera automatically focuses on the subject in the focus area in the center of the LCD/viewfinder. Many prosumer and all professional digital cameras allow you to select additional autofocus areas which are indicated on the LCD/viewfinder.

Example of a camera with a multi selector button (extreme right) to select the AF area spot. The selected area spot is indicated on the main LCD by a red bracket.

In “single AF” mode, the camera will focus when the shutter release button is pressed halfway. Some cameras offer “continuous AF” mode whereby the camera focuses continuously until you press the shutter release button halfway. This shortens the lag time, but reduces battery life. Normally a focus confirmation light will stop blinking once the subject in focus. Autofocus is usually based on detecting contrast and therefore works best on contrasty subjects and less well in low light conditions, in which case the use of an AF assist lamp is very useful. Some cameras also feature manual focus.

This article is written by Vincent Bockaert,
author of The 123 of digital imaging Interactive Learning Suite
Click here to visit 123di.com

Go here to visit the glossary pages of DP Review

Fujifilm X100S First Look

The Fuji X100S is a much coveted camera, it definitely has style, if what you look for in technology is something that harks back to before you were born. It also has a pedigree of fine technical excellence so do you want one?

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When Fujifilm announced its FinePix X100 retro-styled compact at Photokina 2010, it instantly captured the imagination of serious photographers. With its fixed 23mm F2 lens and SLR-sized APS-C sensor, it offered outstanding image quality, while its ‘traditional’ dial-based handling and innovative optical/electronic ‘Hybrid’ viewfinder gave a shooting experience reminiscent of rangefinder cameras. On launch its firmware was riddled with frustrating bugs and quirks, but a series of updates transformed it into a serious photographic tool. Certain flaws remained, apparently too deeply embedded into the hardware to be fixable, but despite this, it counts as something of a cult classic.

Fujifilm X100S key features

  • Fujifilm-designed 16.3MP APS-C X-Trans CMOS II sensor
  • On-sensor phase detection autofocus
  • Novel colour filter array to suppress colour moiré, no optical low-pass filter
  • EXR Processor II image processor
  • Hybrid optical / electronic viewfinder with 2.35M dot LCD EVF
  • Analogue dials for shutter speed, aperture and exposure compensation
  • Fixed 23mm F2 lens (same as X100)
  • Improved manual focus system (more responsive focus ring, focus peaking and split-image displays)
  • 2.8″ 460k dot LCD
  • On-screen ‘Q’ control panel and tabbed menu system
  • Full HD 1080/60fps movie recording, 36Mbps bitrate
  • Socket for electronic remote release/stereo microphone

SEE ALL OF THE ARTICLE ON DP REVIEW HERE

By the way it costs about £1000

Canon EOS 700D

Canon have released details of the new camera added to their stable, this is effectively a replacement for the 650D, improvements keep coming and new cameras offer better facilities and quality and this one is no different.

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With the EOS 700D/Rebel T5i, Canon’s made an early move to replace last year’s 650D/Rebel T4i, though one with only very minor refinements. Indeed the changes over the 650D are so subtle that it’s the olderT3i/600D that stays on alongside the 700D – while the too-similar 650D fades into the sunset. The only real changes are that the 700D offers real-time preview of Creative Filters in Live View mode, includes a redesigned new mode dial that turns 360 degrees, and has a new ‘upmarket’ body finish.

Apart from those additions, the 700D is essentially identical to the 650D, making this the least distinct upgrade we’ve seen in this range of cameras. Elements carried over include the 18MP CMOS sensor, a 9-point cross-type AF sensor, 3-inch, a 1.04m-dot vari-angle LCD screen, and Full HD video mode. Its Hybrid AF system was also brought over from the 650D, and while the simultaneously announced 100D/Rebel SL1’s Hybrid AF II covers a wider area than the one here, neither is said to be any faster than the rather slow implementation on the 650D.

Canon EOS 700D / Rebel T5i key features

  • 18MP APS-C ‘Hybrid CMOS’ sensor
  • Phase-detection AF from imaging sensor for Live View and Video
  • Continuous autofocus in movie mode with subject tracking
  • New 18-55mm STM kit lens with stepper motor for improved live view/video autofocus
  • 14-bit DIGIC 5 processor
  • ISO 100-12800 standard, 25600 expanded
  • 5 fps continuous shooting
  • 9 point AF system, all sensors cross type, central sensor F2.8 (from 60D)
  • 63 zone iFCL metering
  • 1080p30 video recording, stereo sound with internal or external mics
  • 1.04m dot 3:2 touch-sensitive vari-angle ClearView II LCD (capacitative type, multi-touch support
  • more information can be found of the excellent DP Review site here
  • Amazon are currently offering this camera at £930

 

Canon 6D First Review

Hot on the heels of the new Nikon D600 comes the Canon 6D, bit like buses…. Calumet Photo are quoting about £1800 for the body only

The 6D is apparently not a replacement for the 5D but a stable mate designed with features for landscape, travel and outdoor photographers. It is lighter than the 5D so easier to carry around and has geo-location GPS facilities so you can tag images with their exact location and built in wifi for transmitting and sharing images. Here are some details

A 20.2-megapixel DSLR featuring a full-frame sensor and compact design. Ideal for portrait, landscape and travel photography, offering tight control over depth of field and a large choice of wide-angle EF lenses.

  • Enjoy the full-frame advantage with a 20.2 megapixel CMOS sensor, for a wider choice of wide-angle lenses, great image quality, and more depth-of-field control
  • Tough magnesium-alloy body and compact design
  • Great in low-light. Shoot at max ISO 25,600 (expandable to ISO 102,400) and with precise AF, even in conditions as dark as -3EV
  • Follow the action with 11-point AF and 4.5 fps shooting
  • Built-in GPS geotags images with location
  • Wirelessly control and download from your camera with built-in Wi-Fi • 14-bit DIGIC 5+ processor for accurate colour reproduction
  • Shoot Full-HD video
  • Live View composition on a 1,040,000-dot 7.7cm (3.0″) ClearView LCD screen
  • The ever reliable people at DP Review have a full preview available here

The EOS 6D is best seen as a full frame version of the EOS 60D – indeed it’s very similar in both control layout and dimensions. Its front profile is very similar to the Nikon D600, but it’s rather slimmer front-to-back, and lighter too. However it differs from the Nikon in a number of key respects; for example it has Wi-Fi and GPS built-in, while the D600 offers a distinctly higher spec’ed autofocus system, dual card slots and a built-in flash.

The EOS 6D is built around a new Canon CMOS sensor, which offers a pixel count of 20.2MP (compared to the D600 and A99’s 24MP, or the 5D Mark III’s 22MP). In concert with the DIGIC 5+ processor it offers a standard ISO range of 100-25600, expandable down to 50 and up to 102,400. The AF system has 11 points, but only the central one is cross-type (i.e. sensitive to both vertical and horizontal detail). However according to Canon to will operate at extremely low light levels; right down to -3 EV – a stop dimmer than the 5D Mark III.

The EOS 6D’s most eye-catching additions are integrated GPS and Wi-Fi – their first appearance on a Canon SLR. The GPS unit includes exactly the same functionality as on the company’s compacts – it can embed location data into every image, and has a logging function that can keep track of where you’ve been through the day. This, we suspect, will be most-popular with landscape and travel photographers.

The integrated Wi-Fi unit has the basic functionality you might expect, allowing transfer of images to a smartphone or tablet, and direct upload to social media sites such as Facebook and YouTube. You can also send images directly to a Wi-Fi-enabled printer. But we think more photographers are likely be interested by the fact that it can also be used to turn your smartphone into a wireless remote control via Canon’s EOS Remote app for iOS or Android, complete with live view and full control of exposure settings.

The EOS 6D gains Canon’s silent shutter mode that we saw on the 5D Mark III, which offers quieter, more discreet shooting. It gets in-camera HDR and Multiple Exposure modes, but disappointingly these are JPEG only, unlike on the 5D Mark III that also records RAW files. There’s also a single-axis electronic level to check for wonky horizons. READ THE FULL PREVIEW

You may find this comparison site useful as well as the DP Review pages, this lists the differences between the Nikon D600 and the Canon 6D

Nikon D600 Released September 18th

New cameras come along at an alarming rate, is it true that we are expected to buy a new camera every three years, I am sure I read that somewhere. There is no doubt that as technology improves daily it is very tempting to want the latest and best, not because it is the latest but because we can produce better images under more difficult conditions. One thing I don’t particularly like about the march of technology is the way that the camera manufacturers always seem to want to wrest control from us, the photographers, and have us use their, the cameras, automatic functions more. The idea seems to be that the camera knows best and can make better judgements about the picture we are about to take. WRONG. A camera that delivers better quality, images with smoother tone, less noise, better colour, able to handle subject brightness range better, all the things that make an image just better are to be applauded but e.g. some auto focus gizmo that means it is harder for me to focus where I want is not a help, it is a hindrance.

There is a new Nikon camera that will no doubt have many salivating. It is a full frame dslr 24 megapixel with HD video, sounds like a competitor for the Canon 5D.

Here is a bit from a Nikon website The D600 is a new model added to the Nikon FX-format digital SLR lineup with a smaller size and lighter weight–approx. 141 (W) x 113 (H) x 82 (D) mm, 760 g*1 for excellent portability, yet offers the superior image quality and rendering performance, operation, and durability of high-end FX-format D-SLRs. The D600 is a compact and lightweight camera that offers excellent cost performance. In addition to a new FX-format CMOS image sensor with an effective pixel count of 24.3-million pixels and the same EXPEED 3 image-processing engine built into high-end models, the D600 inherits a number of advanced features from its high-end cousins, including an optical viewfinder with frame coverage of 100%*2, a large and clear, 3.2-inch LCD monitor with a wide viewing angle for superior visibility, and the same dust- and water-resistance as the D800

The best go to site for camera reviews DP Review only has a preview so far but anything they have to say is always worth reading, you can find that here

Nikon D600: Key Specifications

  • 24.3MP Full-frame CMOS sensor (10.5MP DX-format crop mode)
  • ISO 100-6400 (expandable to ISO 50-25,600 equivalent)
  • Maximum 5.5fps continuous shooting
  • 39-point AF system with 9 cross-type AF points
  • 3.2in 921k-dot LCD screen
  • 1080p30 full HD video mode with stereo sound recording
  • Headphone jack for audio monitoring in movie mode
  • Uncompressed video recording via HDMI
  • Single-axis electronic level in viewfinder, duel-axis (pitch and roll) in live view
  • Dimensions: 141mm x 113mm x 82mm (5.5 × 4.4 × 3.2 in).
  • Weight: 760 g (1.6 lbs) (camera body only, no battery)
  • Calumet here in the UK say the camera will be released on September 18th the price listed in the US is about $2100 so expect to pay about the same in pounds here

Canon EOS 650D

Canon have added a new model to its range and all the evidence before full user reviews are available is that it has the new Digic 5 processor plus other new technologies like a dual focusing system and articulated screen with touch screen capabilities.

Introducing the latest model in the Canon EOS system, the 650D featuring a 270 degree vari-angle clear view touch screen – a first on any Canon DSLR. View your images, pinch to zoom and even fire your shutter on the 1,040,000 dot LCD screen.

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The Canon EOS-650D also features

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  • 18 MP CMOS sensor
  • Full HD movies with continuous AF and editable video snapshot modes
  • Digic 5 processing
  • 63 zone light metering for optimum exposure in all light conditions
  • 4 ways to focus
  • Integrated Canon Speedlite transmitter

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As always my first place for decent info rather than just rumours is the excellent DP Review

Here is a brief summary of what they have to say

“The EOS 650D offers outstanding image quality and performance. Its newly-developed 18MP APS-C Hybrid CMOS sensor provides super-fine resolution, capturing poster-sized images that are rich in colour and detail. Ideal for shooting in low light without flash, the camera features a native 100-12,800 ISO range, allowing the capture of naturallooking shots with minimal noise, while an expanded ISO 25,600 range also offers the ability to shoot in more extreme low-light conditions.

The EOS 650D is the first entry-level EOS to be powered by Canon DIGIC 5 processing, offering greater speed, responsiveness and advanced colour rendition. DIGIC 5’s 14-bit image processing provides beautiful and subtle transitions between colour tones, such as those of an evening sky, and its vastly-increased power also makes the camera ideal for capturing fast-moving action such as football or other sports.

The new dual AF system makes it easy to capture sharply-focused shots of all subjects, whether capturing stills or movies. A superior 9-point all cross-type AF system provides exceptional performance during stills shooting, offering precision accuracy when capturing sports, action and wildlife. Additionally, a new Hybrid AF System offers continuous autofocusing during movie recording, and when shooting in Live View1 mode…….

Touch control and Vari-angle flexibility

Getting the perfect shot has never been easier thanks to the new 7.7cm (3.0″) Vari-angle Clear View LCD II Touch screen. Featuring capacitive technology, the screen is highly responsive and supports a variety of multi-touch gestures, such as pinching and swiping – making it easy to access shooting modes, alter settings and even capture a shot using the screen alone.

Touch control adds a different dimension to Live View shooting. You can select AF points, track faces and objects, and fine-tune image settings via the camera’s Quick Control screen. Navigation is instant and intuitive, while pinch-zooming in playback provides a great way to check the finer details of a shot. The Vari-angle hinge allows the screen to be angled and tilted to suit virtually any situation, while a super-sharp 1,040k-dot resolution ensures every detail is clearly displayed.”.…MORE

The expected price upon release is from £699 so it is not excessive expensive for a state of the art digital slr camera, release dates seem to vary but will be generally available over the summer.

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Here is a bit more info in easy to digest points Canon EOS 650D: 10 things you need to know

Hands On with the New 16.2MP Full-Frame Nikon D4 Professional DSLR

Things just got interesting again. Yes, as has been rumored and leaked for several weeks (months?) now, Nikon just officially unveiled its new flagship professional digital SLR: the Nikon D4, which uses a 16.2-megapixel FX-format (aka full-frame) CMOS sensor that can shoot at up to 11 frames per second and capture full 1080p HD video.

“The D4, which is the successor to the 12.1MP D3s announced back in 2009, will start shipping in late February 2012 for $5999.95. So start counting your pennies now!

The announcement of the new Nikon D4 comes several months after Canon also announced a new flagship professional DSLR, the 18MP Full-Frame EOS-1D X. Though the 12-frames-per-second shooting, 1080p-capable Canon 1D X was announced back in October, it won’t start shipping until March 2012 and will sell for quite a bit more than the Nikon D4: $6,800.

The Nikon D4 will makes its debut at the CES show in Las Vegas next week.” By Dan Havlik..………..MORE

Nikon D4 Specs

• 16.2MP Full-Frame (FX-format) sensor, sized at 36 x 23.9mm

• 91,000-pixel sensor dedicated for 3D Color Matrix metering to assist with autofocus and scene recognition

• EXPEED 3 image processor

• Back-illuminated buttons

• 51-point AF System which is same as in previous model but with new cross-type sensors

• ISO range from 50 to 204,800

• 10 frames per second still shooting for up to 200 JPEGs; 11 fps shooting but focus and exposure are locked at the first frame

• Full 1080p HD video at 30p; 720p shooting at 60p for slow motion

• 0.012 second start time; shutter lag rate at 0.0042 second (same as previous model)

• Two memory card slots: one for CompactFlash cards, the other for new XQD memory cards

• 3.2-inch 921,000-dot LCD screen on back

Canon EOS 1D MkIV Review

An in depth review of the Canon flagship camera by Bob Atkins and Theano Nikitas

The Canon EOS 1D Mark IV is the latest in Canon’s 1D series DSLRs. The 1D series is unique in its use of an APS-H format sensor (28.1×18.7mm). The sensor is larger than APS-C and so can yield higher image quality, but is smaller than full frame, which means that the file size is smaller and the reflex mirror can be smaller and lighter and so the camera can operate at higher speeds (10 frames per sec). The high speed operation of the 1D series cameras has made them the first choice for many sports and action photographers. Like other 1D and 1Ds series cameras, the EOS 1D MkIV has an integrated grip with a second set of controls for vertical shooting, a high capacity battery pack, high strength construction and the body is weather-sealed for operation outdoors in the rain.….more

1D MkIV Major Features

 

  • New 16.1 Megapixel APS-H CMOS sensor
  • 10 frames per second continuous shooting
  • Up to 121 large JPEG images in a single burst
  • New 45-point wide area AF with 39 cross-type sensors with f/2.8 sensitivity
  • New upgraded AF system designed for high speed tracking of moving subjects
  • High-speed Dual “DIGIC 4” processors for fast operation and high image quality
  • 12,800 high ISO expandable up to 102,400
  • Full HD movie recording at 30, 25 and 24 frames per second (fps)
  • 3.0″ Clear View II LCD with Live View mode
  • Durable dust and water resistant body with 76 rubber seals
  • 1/8000s shutter with 300,000 cycle rating and 1/300s sync

 

City Scapes at night

If you have a tripod and live in a city then night photography is something you will enjoy, how could you not. Add in some water and your opportunities for extravagant imagery multiplies. Exposure is an issue because your camera may want to even out the light and dark areas so you end up with pictures that are just too light with burnt out highlights so be prepared to play with the exposure compensation control. Focusing can also be a problem as the camera’s auto focus struggles in situations where there is not much light, as all your main subjects will be beyond infinity you can put the camera into manual focus and set it to infinity (the sideways 8 symbol). Long exposures or high ISO settings are likely to introduce more noise than you would want but put up with it and enjoy the results anyway.

This post on Lightstalking will give you lots of inspiration

Emmanuel Huybrechts

SChrista