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Archive for the ‘Technology’ Topic

2013.02.26

While people are divided on whether an electronic viewfinder (EVF) or an optical viewfinder (OVF) is better, most have a strong preference based on what they are used to. DSLR users, by definition, use an optical viewfinder which is based on the well established design that has existed since the launch of the first SLR camera.

Mirrorless cameras, on the other hand, use an electronic viewfinder as they cannot have a reflex optical viewfinder that sees through the lens since they lack the mirror to bend the light path that way. The good news is that companies have been working hard at improving EVF technology.

There are both advantages and disadvantages to EVFs compared to OVFs. The very best ones with high-resolution and high-refresh rates are actually quite suitable for most uses when well-implemented.

EVFs can have the following advantages:

  • WYSYWYG: With an Exposure-Priority display, like those of Sony SLT and NEX cameras, you see something much closer to the results before shooting. With an OVF, you see with your eye and therefore have no way of knowing how an image will be exposed. The same is true of White-Balance.
  • Sensitivity: EVF are electronic and can have the signals amplified to produce a bright image even in dark conditions. This makes them usable for framing with ND filters. When using a very dark filter, say an ND400 for example, an EVF still shows an image while an OVF becomes too dark.
  • HUD: An EVF can show detailed information overlaid on the image, including a Live-Histogram and detailed camera status. One can also navigate menus and change almost any setting with the camera at eye-level.

Olympus VF-2EVFs also have disadvantages:

  • Lag: There is a short lag between action happening in front of the camera and what you see.
  • Dynamic-Range: EVFs are small LCD screens and have limited dynamic-range.

Lag is a problem for action and photography where following action is critical. The limited dynamic-range means that it is possible for areas to be either fully white or full black without any details even though details will be captured.

A few aspects are not so clear-cut:

  • Focus: With 1.5 – 2.4 MP EVF it is now quite easy to judge focus. The same cannot be said about most EVFs which have around 200K-350K pixels. Additionally, a lot of cameras can magnify the EVF to assist MF and some can highlight high-contrast edges which is called focus-peaking. The remaining problem for manual focus is lag. Just like the EVF lags action, it lags behind the focus-ring too and on some cameras it is rather hard to get focus exactly right without back-and-forth movements.
  • Coverage: The vast majority of EVFs show 100% coverage. For OVFs, it is sadly the minority.

Keep in mind that implementations vary widely and plenty of EVFs are inexplicably not Exposure-Priority and some do not show the ideal image brightness in low-light. Some EVFs also show an incorrect Live-Histogram.

There are also some minor annoyances such as the need for a camera to be on to see something. With an OVF, it is possible to frame and focus (except for lenses with fly-by-wire focus rings) while the camera is off.

Finally EVFs require a lot of power, often as much as having the rear LCD on, despite being smaller. This makes battery-life similar to using Live-View and roughly half of what it is with an OVF. The actual drain depends on the specific camera of course, usage and power-saving settings.

All in all, modern EVFs are quite usable and Exposure-Priority ones are more helpful to photographers under most circumstances other than fast action.

Neocamera Blog Neocamera.com © Cybernium

2012.11.20

Six years ago, touchscreens were appearing on digital cameras. This was a disturbing trend at the time and still is. While these type of screens may have their place on phones and tablets, there plenty of reasons to avoid them on digital cameras:

  • Smudges: No  matter how many times you wash your hands, that LCD gets smudged! Digital cameras are exposed to sunlight more than any other device and, when it is time to take a shot, the light is what it is. With a phone, you can turn around so that your shadow falls on the screen but a camera has to be pointed in a certain direction to take a specific shot.
  • Gloves: Most modern touchscreen do not respond to gloves. If you photograph in a cold place and take off your gloves each time you take a shot, pretty soon you lose sensations in your fingers.
  • Nose: A camera with a touchscreen is a bad idea but one with a viewfinder and a touchscreen is much worse! With such camers, it is easy to change settings and even fire shots with your nose while trying to frame the image you actually want.
  • Fog: In extreme temperatures, hot and cold, LCDs frequently get fogged up. Any LCD has to be wiped to be usable again but only touchscreens change your camera settings while doing so!
  • Screen Protector: Hard screen protectors prevent touchscreens from being used. That’s a good thing until you realize you paid the the touchscreen which you cant use.

This was a public service announcement for the Aliance Against Touchscreen on Digital Cameras. Please support  this cause by saying No to touchscreens on digital cameras ;)

Should you already have a camera with a touchscreen, you may consult the user manual to find out how to disable it. So far, most of them can.

Neocamera Blog Neocamera.com © Cybernium

2012.11.03

Nine years ago, IBM delivered a display to my desk, the $27,000 USD T220. This is a 9 megapixels 22″ LCD with a resolution of 3840 x 2400. Of course, being IBM, they did not have a cool name for it and they called it a QWUXGA for Quad Wide Ultra eXtended Graphics Array.

Compared to Apples’s Retina, this is quite a mouthful but indeed but the IBM T220 had a resolution of 204 DPI. IBM claimed they had delivered this technology 10 years ahead of schedule and it seems the estimate is very close. The T220 was introduced in September 2003.

The T220 was an amazing display, it delivered crisp details like never seen before and was… quickly discontinued despite a price drop to $9000 USD. The problem is that technology has a hard time living in a vacuum and other components from 10 years in the future had not arrived yet! The first units ran at 40 Hz and required 4 DVI links, so we used two dual-head graphics card to drive it, which each head driving a quarter of the display. The setup was not pretty and moving images were choppy and everything looked minuscule. An amazing demo but not much of a sell.

Now computers are powerful enough and Apple was first out with ultra-high-resolution displays, up to 2880×1800 on a 15″ laptop which equates to 220 DPI. Just last week, Google produced an even sharper display for its 10″ tablet. This one has a 2560×1600 resolution – the same as my 30″ NEC Multisync LCD3090WQXi-SV – but one third the size. I have not seen either in the flesh yet but it must be truly impressive!

It won’t be much longer until more displays start appearing at those resolutions. Probably on laptops first since smaller displays have better yields and on independent ones after some time. This will give much more realism to images and provide a preview which is considerably closer to prints. Operating system support is needed to allow this to work with legacy applications and Apple has done this very cleverly. We’ll see how Microsoft and Linux address this.

Unfortunately this is also bad news for photographers. Higher DPI onscreen means that more pixels have to be sent to cover the same area. To show a 4×6″ print on-screen currently it only takes a 600×400 pixel image, or 0.24 MP. On a 300 DPI display, we need 9 times those pixels, so 2.16 megapixels. Scale that to 900×600 which gives a more comfortable size for appreciating images and you need to replace 0.5 MP images with 4.5 MP ones. This will sadly open more doors to people stealing images because they will be able to do more with them.

Reality is that images on the web get stolen and used without attribution not just by individuals wanting a cool wallpaper but commercial entities for their websites and even print campaigns. The advent of Retina displays gives those felons more ammunition. Of course one can still showcase image at lower resolution but viewers will see an image which is less sharp than others and most won’t bother understanding why.

Neocamera Blog Neocamera.com © Cybernium

2012.10.23

Plenty of digital cameras, like the just-reviewed Nikon D600,  feature Expanded ISO sensitivities. Briefly, ISO sensitivities are simulations of film sensitivities for digital sensors. Expanded ISO settings are just more of those sensitivities which are not considered part of the normal range. In the case of the Nikon D600, the normal range is 100 – 6400 and the expanded range is 50 – 25600. So sensitivities below 100 and above 6400 are its Expanded ISO sensitivities.



There are two reasons why an ISO is not made part of the normal range:

  1. It is considered a non-trivial drop in quality and the manufacturer does not want users complaining about its performance. For example, if the quality difference between say ISO 12800 and 6400 is much greater than the one between 3200 and 6400. Noise is obviously the most known aspect of image quality which goes down at higher ISOs but dynamic-range and colors are often affected as well.
  2. The camera meters and exposes for the said ISO, say 12800, but the results do not strictly comply with the ISO standard. When that happens, the ISO is rarely stored in the EXIF of the image. This usually happens because of a drop in dynamic-range at the expanded setting which causes the grey-point or mid-tone to shift.

Manufacturers deal with this differently. Canon and Pentax lock out expanded sensitivities by default and users must enable them in a configuration menu somewhere. Nikon and Canon does not use numeric ISO sensitivities to describe them but use labels instead, for example Lo 1.0 for ISO 50 and Hi 2.0 for ISO 25600 on the Nikon D600. Some Olympus cameras simply shows a comment on the LCD when an expanded ISO is selected.

Fixed-lens cameras often lower resolution at Expanded ISO sensitivities. For example, the 16 megapixels Fuji Finepix HS30 EXR drops to 8 MP at ISO 6400 and down to 4 MP at ISO 12800. This is a technique used by many but perfected by Fuji called pixel-binning where multiple pixels are used to simulate a larger one. Fuji’s EXR sensors have a special color-filter which lets it bin pixels of the same color together, making interpolation easier.

To the right is an ISO 3200 crop from the 12 MP X-S1 and below it is a 6 MP from its expanded ISO 6400 mode. The image is smaller in terms of resolution, so details look bigger at 100% which magnifies noise. On a fixed print size though, they pretty much even out which is not always the case.

When to use expanded ISO settings? The first part of the answer is to know your camera. Now what each ISO looks like in terms of image noise and retention of details. The second part is to consider the intended use of the image being taken. The smaller the print, the less visible the noise. Modern cameras can produce small 4×6″ prints at stellar ISOs now. The most important consideration is what else can be done to get the shot?

  • Lowering shutter-speed is viable for still subjects but you may need to support your camera on something, or simply use a tripod. For subjects in motion, it depends on the motion but by the time light is that low, you are probably at the minimum already.
  • Opening the aperture is doable sometimes at the expense of reduced depth-of-field.
  • For still subjects again, one can also use multi-exposure techniques and blend several under-exposed but lower-ISO shots by software.
  • Finally, you can consider moving or adding lights or moving the subject closer to a light source. This of course depends on the compostion and subject entirely. Still, this is one of the easiest tricks to get better light. Some willing subjects will even do the moving themselves!

Neocamera Blog Neocamera.com © Cybernium

2012.02.22

The Digital Photography Computer Buying Guide was just updated for 2012. This new feature article covers the basics of choosing a computer for working with digital images and specific up-to-date recommendations for computers and components. Every part from the display to the power-supply is covered, how to build your own image processing powerhouse or how to find one already built and then improve it.

Writing this feature was a hands-on experience since it was time to make new computer to go along the one built for the 2009 article. Costs have gone down quite a bit and the potential for performance even higher. All parts were ordered collectively from our sponsor New Egg (For Canadians or for Americans) and the experience was speedy and fantastic. One defective part which was bought refurbished was returned without cost and a replacement shipped back within 48 hours. Talk about excellent service!

As expected, this new computer really rocks with the Adobe Creative Suite 5.5 Web Premium including Photoshop, Illustrator, Acrobat and Photoshop Lightroom 3.6. Those not upgrading a previous computer will also need a system. For working with these essential Adobe products to their full potential, a 64-bit operating system such as Windows 7 Home Premium 64-bits from NewEgg.COM or from NewEgg.CA.


Neocamera Blog Neocamera.com © Cybernium

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