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Sony Alpha A55 – Review Part 3

16th March 2011

In this final Part 3, I’ll show you additional examples of some of the innovative and easy-to-use features that make the Sony Alpha A55 my recent favorite camera.

You can read about the “standard” features of the Sony Alpha A55 in Part 1 of my review. And in Part 2, I describe my experience using several of the A55’s unique features.

D-Range Optimization

When shooting a scene that has high contrast, you may notice that the shadow areas are likely to lack detail and/or the highlight areas are overexposed.

To counter this tricky lighting, the A55 offers D-Range Optimization that compresses tones to preserve detail in both shadows and highlights.

This feature is not unique to the A55; Canon offers a similar feature which it calls Auto Lighting Optimizer and Nikon uses the moniker Active D-Lighting.

However, the A55 offers five levels of D-Range optimization. To use it, press the dedicated D-Range button on the top of the camera to reveal the DRO menu item and toggle between Auto, Lv 1, Lv 2, LV3, Lv 4 and Lv 5.

In the high contrast winter photos below, you can see that the D-Range reveals much more shadow detail at Lv 5.

D-Range off

D-Range Lv 1

D-Range Lv 5

High Dynamic Range – in-camera

The A55’s High Dynamic Range (HDR) feature has a similar goal as D-Range Optimization, namely to maintain detail in shadows and highlights. HDR photography attempts to reduce the contrast levels of a scene so that the scene can be displayed with maximum detail on a print or display device. For the last few years, HDR has been popularized by using software to combine multiple images within the computer. The A55 is one of the first to offer it easily and automatically in-camera.
For HDR, the A55 take 3 successive photos with varying exposures (bracketed). To use it, press the dedicated D-Range button on the top of the camera to reveal the HDR item. Then toggle between Auto, 1.0 EV, 2.0 EV, 3.0 EV, 4.0 EV, 5.0 EV and 6.0 EV. For example, when set to 3.0 EV, three images are captured: one at the normal exposure, one at 3 stops overexposed (+3.0 EV) and one at 3 stops underexposed (-3.0 EV). The A55 then writes two images to the SDHC card: one at the normal exposure and a second that has been processed to combine the predominantly shadow detail from the +3.0 EV capture, the predominantly highlight detail from the -3.0 EV capture and the predominantly midtone detail from the normal exposure.
normal exposure	HDR 3.0 EV
normal exposure	HDR 5.0 EV
normal exposure	HDR 6.0 EV
Some users are surprised that the HDR images appear to have low contrast, but this is a by-product of having to reduce such a wide range of exposure values to level suitable for a display device or printing. While it may not produce acceptable results in all situations, I’ve been happy with many of the A55’s HDR images that I’ve captured. Note that HDR is not available unless the A55 is set to capture JPG only images (not RAW).

Multi Frame Noise Reduction – in-camera

Multi frame noise reduction is the A55’s “stealth” feature. For some reason, it hasn’t been widely promoted by Sony. In fact, I didn’t know about multi frame noise reduction until one of the Sony reps explained its use to me at a recent trade show.

When set to use this feature, the A55 captures six successive images and merges them to produce a single image with lower noise.

Once again, it’s simple to use. Press the ISO button and set the topmost item (labeled ISO) between Auto and 25600. Press the shutter release to capture the scene and a short time later after it is processed, the image is written to the SDHC card.

Left: image captured at ISO 1600;
Right: image captured at ISO 3200 with multi frame noise reduction.
Click to see an enlargement.

You can also click here
to see a more detailed full size image

Briefly, the process works like this: the camera automatically takes 6 frames at the currently settings: shutter speed, aperture, and ISO. It combines them into a single JPEG image by carefully aligning the 6 frames during compositing while at the same time using proprietary techniques to reduce noise level equivalent to two ISO exposure levels.

Above, you can clearly see that the noise level of the rightmost image is significantly less than the leftmost image even though it was captured at a higher ISO setting. I experienced an equally reduced noise level in several other images that I shot in low lighting conditions. So I find multi frame noise reduction to be a very useful yet unexpected feature.

Note that multi frame noise reduction is not available unless the A55 is set to capture JPG only images (not RAW).

Sweep Panorama – in-camera

While I’m a fan of panoramas, the task of setting up a tripod, adjusting the camera to capture a series of images, post-processing the individual images and finally pasting them together afterwards using stitching software often takes a few hours. With the A55, you can create a panorama automatically. First, you set the mode dial for panoramas. From the shooting menu, you can select either 2D or 3D panoramas. For 2D panoramas, you choose a direction for panning: left to right, right to left, up to down or down to up direction and a format: standard or wide. For 3D panoramas, you choose a direction for panning: left to right or right to left and a format: 16:9, standard or wide. As its name suggests, to capture a scene you press and hold the shutter while slowly sweeping (panning) the camera in the chosen direction. After a specified number of images are captured, shooting ends and the A55 stitches together the separate images to create the panorama and writes a single one to the SDHC card. It’s as simple as that. You’ll want to take a few test shots to determine the speed at which you should sweep the camera. To guide you, the A55 displays helpful text messages in the viewfinder with shooting suggestions.

Below are a pair of panoramas that I captured – one with the camera held in the horizontal orientation and the other with the camera held in the vertical orientation.
Death Valley panorama captured horizontally 8192 x 1856 pixels
Bryce Canyon panorama captured vertically 3872 x 2160 pixels
I also captured a few 3D panoramas. However, to display a 3D panorama, I had to have a 3D television and special eyewear. The 3D panoramas are very impressive. The 3D panorama will appear as a 2D panorama if you do not use a 3D television nor special eyewear. I really enjoy the ease at which I can capture a landscape using the Sweep Panorama.

Earlier in the review, I mentioned that I’ve had extensive experience with a large variety of DSLRs. These range from low-priced entry to expensive professional level. I mention this so that you understand that my fondness for the Alpha A55 is not just “puppy love”.

When I first learned about the Alpha A55, I was amazed by the number of innovative features that Sony claimed to have packed into this new body. In the two months that I’ve used this camera, I remain impressed by the results that I’m seeing in the images and the ease with which I am able to capture them.

If the Alpha 55 is any indication of the kind of innovation that we might expect from Sony in coming months, I’ll be anxiously watching for more.

It looks like Sony has a winner. The Sony Alpha A55 is certainly a winner in my book.

Written by Arnie Lee

Post tags: 3D, 3D panorama, A55, Alpha 55, Bryce Canyon, D-Range, Death Valley, dynamic range, HDR, multi frame noise reduction, national park, noise reduction, panorama, Sony, translucent mirror

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Sony Alpha A55 – Review Part 1

12th March 2011

A New Breed of Camera

I first laid my hands on the Sony Alpha A55 (and the smaller, less expensive Alpha 33) at the PhotoPlus Expo in New York City last September.

What interested me in this new camera was its fixed translucent mirror. In a conventional DSLR, the reflex mirror reflects the image into the viewfinder and then swings out of the way when you press the shutter to send the image to the “film” light sensor. In the Alpha 55, the translucent mirror sends a small portion of the incoming image to the viewfinder and the remainder to the “film” light sensor. This stationary mirror gives the camera several unique features that I’ll describe shortly. This technology isn’t new. In the early 1960′s Canon made a model called the Pellix using a similar scheme with a pellicle mirror. My uncle bought this camera back then, one of the first to have Through The Lens metering (TTL) and it served him well for many years.

The A55’s translucent mirror eliminates the reflex mechanism providing a space, weight and cost savings. Removing this mechanical assembly also allows for a higher frame rate. Next, the electronics measuring the auto exposure remain uninterrupted from frame to frame giving instant responses to varying changes in lighting. Similarly, the auto focus system stays 100% available – a very important consideration for high speed continuous shooting.

(more…)

Post tags: A55, Alpha 55, Sony, translucent mirror

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Upcoming Reviews

29th January 2011

I made it a point to attend several trade shows recently – Photokina in Cologne (September), PhotoPlus in NYC (October) and CES in Las Vegas (January). I spent a lot of time walking up and down the aisles at the shows and was able to get hands-on demos of many new pieces of photo equipment and accessories.

Several readers have asked about our plans for reviews of some of these items, so I thought I’d drop a few lines to let you know that we’ve already started reviewing the following items and are putting them through the paces. Additionally, we’ve added another tablet computer to our inventory and are just now logging a few dozen hours studying how it might come in handy for photographers.

	Color Nook – this is the new color version of Barnes & Noble’s earlier black and white e-book reader. The display makes it great for reading ebooks that include full-color illustrations and photographs.
	Eye-Fi – this innovative wireless SD card is not new, but the improved software has many new features for automatically sharing your photos with other sites.
	Samsung Galaxy Tab – this recently introduced tablet computer is aiming to grab some of the would-be iPad enthusiasts. It’s more compact than the iPad and sports a few nice features.
	Sony Alpha 55 – this new DSLR has a slew of innovative features. Demoing it at the PhotoPlus Show, I felt that is a groundbreaker. Others must have felt that way too; it was on backorder for six week.
	Sony SnapLab – not everyone needs the power or speed of this medium volume printer. But having a SnapLab gives you a very convenient way to get prints directly from your digital media or bluetooth mobile device.