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Figuring out how to power cameras and other gadgets in Europe can seem tricky, but it’s easy enough once you know how.

Florence streets lit by 220 volts
Florence streets lit by 220 volts

The trick is to look for a sticker on the power adapter or plug that tells you the input voltage. The magic words to look for are something like this: “100-240V AC 50/60Hz”. 100-240 tells you the voltage range: Europe standardized on 220 volts for its standard household power supply. So the voltage range on your device needs to cover 220 volts or more for your electronics to work in Italy, France and most of Europe. If your gadget can cope with a higher range, that’s OK too (e.g. “90-240”).  In all of these cases, you just need a simple (and cheap) plug adapter and the device itself will automatically adapt to the higher voltage.

Here’s a video that shows you the various plug adapters and how they work:

Almost all of today’s small electronics like cameras, mobile phones, laptops and chargers automatically adapt and you just need a plug adapter.

Devices that use more power, like hairdryers or portable kettles, almost always only work on US 110 volts. Check the label: if it says something like “120VAC” or a smaller range such as “100-130V” then you cannot use it in Europe without a voltage transformer. This is extremely important: if you plug a standard 120V hair dryer into 220V using a plug adapter, it will immediately burn out the dryer and may cause a fire.

The good news is that there are travel hairdryers etc. available that are designed to adapt to the voltage. But in general it is much harder to design a high power device that is adaptable to 110V and 220V, because to do so you need a very heavy and large voltage transformer.

External voltage transformers are available: they are rated by the amount of power they can supply, in Watts. So it might say on your electric kettle “1000W” — that means you need a transformer rated for 1000W or greater. Again, it can be dangerous to exceed the maximum rating of a transformer: it will eventually melt and may catch fire. The more transformer a converter can supply, the larger and heavier it will be, so beware of smaller adapters if you need a lot of power.

The simple approach? Take devices that don’t need voltage conversion. The good news is that these days, most of them don’t. Take a travel hair dryer rather than lugging around a high current transformer: it’s much lighter. Simply don’t take portable kettles and other high power devices.

Photography began with the concept of capturing light in a single plane — the idea of what’s in and out of focus in an image has been central to photographic composition for more than 100 years. The photographer’s job has been to direct the viewer’s attention by deciding which subjects are in focus, while ensuring that the background (and less frequently, the foreground) are appropriately blurred. The Lytro camera turns that entire concept on its head by delivering a “living image” where the viewer can change the point of focus to explore the image.

When my Lytro arrived, I couldn’t wait to try it out. What follows is my review of the 1.0.0 version of the Lytro camera and 1.0.0 software following my attempts to take good photographs.

I’d love to embed some Lytro photos in this post, but that doesn’t seem to work. So, instead, here’s a link to my Lytro gallery (opens in a new window): Lytro example

The Lytro camera “out of box” experience is very well done and will be very familiar to anyone who owns an iPod or iPhone. It comes in a white box, with the camera held firmly in place with plastic inserts. Underneath the camera is a white cardboard box containing the paperwork, lens cap, cleaning cloth, wrist strap and USB cable.

The camera itself is small — just 4.4 inches long — and arrives with some charge in the battery so you can start shooting immediately. It’s shaped like a square tube, with the lens at one end and a small viewing screen at the other:

Lytro light field camera
Lytro light field camera

A small power button on the bottom turns on the camera, and the shutter button is on the top. Zooming is accomplished by dragging a finger left and right on the rear top edge of the camera. It’s a little clunky, as it can be hard to set just the right composition, but it works.

The camera is fully automatic: it sets shutter speed and ISO automatically with a fixed f2 aperture. You can tap on the rear screen to tell the camera the exposure metering point and it will do its best. The Lytro needs a wide aperture to capture the best light field — the direction of the light as well as its intensity and color. There’s a little clicking sound when you point the camera at a very bright object like the sky on a sunny day, and exposure is reduced. I suspect it’s inserting a neutral density filter inside the lens barrel to reduce the light intensity.

In “Everyday mode” (the default), the Lytro takes photos instantaneously when you press the shutter button. Lytro makes much of this “instant capture” capability in its marketing, because a light field camera doesn’t have to focus. In theory, yes. In practice, not so much, which is why there’s “Creative mode”, accessed by swiping a finger upwards on the rear screen and tapping a small icon, allowing you to focus the camera. The physics of optics has crashed the “focus free” light field party here: the camera has to focus the lens so that the captured light field has a useful range of potential focus planes.

The net? The Lytro camera requires very careful framing and composition of subjects to give the viewer an interesting set of subjects separated by distance. While the camera might be point and shoot, the composition work is anything but instantaneous! Creative mode offers more flexibility in composing the subjects by distance (handy if they are inanimate) and careful control of the camera to ensure it is properly “focused”. The square (1:1) aspect ratio of the image doesn’t help with composition, making it hard to get everything into the frame. The camera would be easier to use if it had a wide aspect ratio, as there would be more room in the frame for the subjects.

This is really the crux of the challenge presented by the Lytro: how to use it to produce an effective photograph that is interesting and aesthetically pleasing for the viewer. Many of the examples on the Lytro website are contrived compositions with near and far elements to show off the novelty of being able to re-focus after the fact. If that is all there is for light field images, then its impact on photography has been dramatically over-hyped.

Plugging the camera into your Mac (Windows support just shipped) allows you to install the Lytro Desktop software — a nice touch. Once installed, you unplug and replug the camera to download images. You can then view the images — though not at full size — and change the focus point. You can also share images on Facebook and Lytro’s own website, and export JPEGs (so I’m told — I have never managed to find this function in the software). The only effective way to show an image is through the flash file stored on the Lytro website, which is severely limiting.

Lytro touts the camera’s low-light capabilities, but I think that’s a mistake. There is significant noise, banding, lines and other odd artefacts in low light. Shutter speeds are low, even at f2, so camera shake is a real problem, and there’s no flash integration.

Overall, the Lytro camera is intriguing more for future possibilities than what it can do today. Version 1.0.0 is pretty basic and effective composition is extremely time-consuming and requires full cooperation of your subjects. With light field photography, we ought to be able to produce 3D photographs, change the viewers position, tilt and shift the plane of focus to our liking… there are many more possibilities than capabilities in the current software. Today, I find myself leaving the Lytro at home more often than I take it out, and that’s a shame.


Thinking about buying a new digital camera? The best advice I can give you is to avoid maxing out megapixels and you’ll get sharper photographs with less grain (noise). This seems counter-intuitive, but is the effect of camera technology running into physical limitations of lenses and light itself.

David Goldstein has written a full-length paper that explains the physics, but here are the key take-aways on megapixels:

  • For a full-frame (35mm) SLR camera, 25 megapixels is about as good as it gets.
  • For a smaller “APS” digital SLR camera, about 20% smaller than 35mm, 10 megapixels is the point of diminishing returns, and 15 megapixels is on the edge (and has noticeably more noise)
  • For a pocket camera where the sensor is about 1/5th the size of 35mm, 4-5 megapixels is the point of diminishing returns, 10 megapixels is pushing it even at very wide apertures, and 12 megapixel or greater pocket cameras will take disappointingly fuzzy pictures at aperture f/2.8 or greater.

Adding megapixels is good until it’s not

Why is this? Fundamentally, camera manufacturers have to balance increasing resolution from more megapixels with two competing forces: noise from the digital camera sensor and softness caused by lens diffraction. You’ve probably seen that photos taken at ISO 1600 on your camera are much more grainy than those taken at ISO 100 — that’s what noise looks like in your pictures. At the same time, the lens aperture (f-stop) puts an upper limit on how much detail can be resolved by the camera. Overall, more megapixels don’t automatically mean better pictures.

Noise is a result of the fundamental physics of light and the way that digital color cameras capture images. Light is made up of photons, with more photons meaning brighter light. The digital camera sensor counts the number of photons that arrive at each pixel to build the overall digital image. In a 21-megapixel 35mm digital camera such as the Canon 5D Mark II, there are about 20 photons hitting each sensor pixel in the darkest (shadow) areas of the image, assuming a perfect lens. That’s not very many, and it gets worse because of the way digital cameras deal with color. A red, green or blue lens covers each pixel so that only light of that color is detected at each pixel. Dividing 20 by 3, that’s just 6 or 7 photons arriving at each pixel.

Even with a super efficient sensor, this means there’s a lot of noise due to mis-counting of photons.  If we add more pixels to the sensor, the number of photons arriving at each pixel goes down because each pixel has to be smaller, which means more noise. That’s why adding more megapixels makes the photos more grainy, especially in shadow areas.

When it comes to image resolution, adding more megapixels helps the camera resolve more detail – up to a point. Adding more pixels reduces the pixel size on the sensor, which also increases the effects of diffraction, caused by the lens. Diffraction is a fact of life: Isaac Newton discovered that light beams spread into a circle pattern as they pass through an aperture such as the iris of a lens. Diffraction effects make pictures look “soft” and lack sharpness. Diffraction softness becomes more noticeable as sensor pixels get smaller because the diffraction circles spread over more pixels.

Too many megapixels can soften your photos

Newton showed that diffraction increases as the aperture gets smaller.  As the f-stop increases and the aperture of the lens gets smaller, diffraction increases. The point where diffraction starts to noticeably affect picture quality is called the diffraction limit. The diffraction limit for a 21-megapixel full-frame (35mm) sensor is f/10. This means that at f/11 or greater, the image will get softer and softer. The limit is f/8 for a 10 megapixel APS-sized sensor, and f/2.8 for a 12 megapixel pocket camera. Most pocket cameras don’t have a lens that offers that wide an aperture!

In other words, while adding megapixels initially increases camera resolution, there comes a point when it leads to noticeably softer pictures (as well as more noise). For example, in this New York Times review of a new, tiny Samsung ST80 14.2 megapixel pocket camera, the reviewer notices that “people and scenery in the background looked murky, and the photos lacked crispness”. Recall that to get a sharp picture on a pocket camera of 12 megapixels, you need f/2.8 or better aperture to avoid softness from diffraction. The ST80 has 14.2 megapixels and a maximum aperture of f/3.3, so pictures are guaranteed to be soft from diffraction – in addition to the extra noise from pixels that are so tiny you can fit 50 million of them in an area the size of your fingernail.

With today’s cameras, don’t obsess over megapixels, and stick to lower pixel counts where possible — especially with pocket cameras, where the limitation in picture quality is more likely to be the lens rather than the sensor.

Think twice about:

  • Any full-frame (35mm) SLR with more than 25 megapixels
  • Any APS sensor (“cropped”) SLR with more than 15 megapixels
  • Any pocket camera with more than 11 megapixels

To find a camera with low megapixel count, use DPreview.com’s Camera Statistics pages. For more than 1600 cameras, DPReview lists the number of megapixels per centimeter squared (cm2) — lower is better. For example, the Canon 1D mark IV has just 3.1 megapixels per cm2 as you might expect for high-end professional gear. The 5D Mark II has just 2.4 megapixels per cm2. The Canon SX210 pocket camera has 50 megapixels per cm2 as it’s a 14.1 megapixel pocket camera with a tiny sensor. Instead, consider the Canon S95 with a pixel density of 23 megapixels per cm2 — a 10 megapixel camera.

Judging by the comments on photography sites, many people have yet to upgrade Adobe Photoshop CS3 to CS4, or Lightroom 1.x to 2.x. Adobe doesn’t update the Camera Raw plug-in for older versions of Photoshop, which is a problem because updates are the only way to get support for new camera models. The same problem exists for Lightroom, where a new version of the program is required.

The Canon 50D isn’t supported in Lightroom 1.4 — only version 2.x. While the 50D is supported in Camera Raw 4.6, which means you can use it with Photoshop CS3, owners of the 5D Mark II are not so lucky: no support in Lightroom 1.4 and no support in Photoshop CS3 either; it’s supported in Camera Raw 5.2 which only works with Photoshop CS4.

To solve this problem, use the latest version of Adobe’s free DNG (Digital NeGative) converter to translate the RAW files from newer cameras into .DNG files. Lightroom 1.4 and Photoshop CS3 can open any DNG file, regardless of the original camera type. The DNG converter can be found here, and there are PC and Mac variants. It is updated at the same time as the Camera Raw plug-in for Photoshop when new camera support is added.

It works in batch mode — you point it at a directory (folder) full of RAW files and it grinds away creating DNGs in another directory. Taking the long view, DNG is probably a better file format for archiving images because it is open, unlike the proprietary camera-makers’ RAW file formats.

Most compact cameras are designed to fit in your pocket and take a basic photo with the minimum of fuss and fiddle. Picture quality is not the most important criterion for most of these cameras. So what are your options if you want a small, simple camera that’s easy to carry around and use — but you also want the best picture quality you can get?

The biggest determinant of picture quality is actually sensor size divided by number of pixels. As I talked about in an earlier blog posting on camera sensor size, more megapixels can actually make your photos look worse. The more pixels that are squashed into the same small area, the smaller the pixels become, and smaller pixels don’t register light as well as larger ones. The result is blotchy, smeary images with a general lack of detail.

To give you some idea of the difference: a digital SLR like the Canon 50D has 4.5 megapixels per square centimeter, whereas the compact Canon G10 has 35 megapixels crammed into the same area.

In a recent test, the Fujifilm Finepix F100fd was a winner. It has 24 megapixels per square centimeter, laid out in a diamond formation and octagonal in shape, compared to square pixels in a grid for almost all other cameras. In the test, the F100fd does very well up to IOS 800 — where it is dramatically better than comparably-priced cameras from Canon, Nikon, Sony and Samsung. See this comparative review at www.dpreview.com for the full scoop. A close second is the Canon SD880 IS (also called the Ixus 870 IS outside the US), with 35 megapixels per square centimeter but, frankly, better in-camera image processing in the camera than its competition.

Digital SLRs are still kings of image quality and camera responsiveness. But you can’t always carry one around, and these two cameras represent good alternatives if you want to get the best picture.