When I was a boy, my father would often set up a pop-up screen, light up the Kodak carousel slide projector, and put on a show of 35mm slides that he'd taken of our family vacations. There was always something riveting and a bit magical in seeing warmly remembered people and places come alive on the big screen in living color. For millions of families back then, the homemade slide show was the only "big screen" experience that existed in the home. People used to load their cameras with Kodachrome anticipating that the photos they took would be shown and experienced as large, brilliant, projected images in a family or communal setting. And it was a great way for families to remember and re-live special times.

Somewhere along the line, the digital revolution changed the expectations of how photographs could or should be experienced. Instead of being projected, people began to expect photographs to be viewed on computer screens and cellphone displays. The communal big screen experience of a projected image got lost. Many people still have not realized that today's high resolution digital projectors can deliver the same family experiences as the Kodak slide projectors of the past. No surprise, I guess, because while projector makers promote their products for home theater, business presentation, and classroom use, they rarely mention photography as a unique application of its own. But the truth is, showing photographs to the family, or the camera club or other group setting is one of the best applications for today's digital projectors.

The question is -- what are the best projectors for photography? As an avid photographer myself I have tackled this question with great personal interest. I work in black/white as well as color, and use both film and digital cameras. I use every aspect ratio format from landscape/widescreen to vertical portrait to square (if you are curious, you can see my work at www.evanpowell.com). So, the big question for me is which projectors would I use to show my own work? What would I recommend to others? Let's consider the issues.

Keys to Great Projectors for Photography

There are four important attributes that make for a great photography projector:

• High native resolution
• High contrast
• Excellent image sharpness
• Excellent color balance

This is the first of a two part article. Here we will examine practical issues related to high native resolution. In Part Two, we will take up the other key factors of contrast, sharpness, and color balance.

One of the most important features of a great projector for photography is high pixel resolution. The more pixels you have to work with, the more detail you can successfully transfer from your image source to the screen. Today's digital cameras and film scanners can capture more detail and texture than can be projected on a digital projector. So to minimize the loss of detail, choose the highest resolution projector you can afford. For most people, that will be a high definition 1080p projector, with a physical pixel matrix of 1920x1080 pixels. (There are higher resolution projectors, but at the moment they are extremely expensive, so we won't spend any time discussing them here.)

We tend to think of today's 1080p projectors as being the ultimate in high resolution. So it may come as a surprise to realize that today's "high definition" HD 1080p projectors are less than half the physical resolution of a typical pocket-size 5 megapixel point and shoot camera. A Nikon Coolpix 5700 5MP camera has a physical pixel matrix of 2560x1920, or just about five million pixels. An HD 1080p projector has a physical pixel matrix of 1920x1080, or about two million pixels. So any picture taken on that little Nikon needs to be digitally compressed in order to display it on a 1080p projector. A high resolution projector will let you minimize the loss of detail when compressing your image files.

Two years ago, I was enthused about the SXGA+ resolution projectors as great tools for photography. At the time, SXGA+ resolution (1400x1050) was much less expensive than 1080p, and they delivered great pictures for the money. However, in the last two years, HD 1080p resolution projectors have dropped like a rock in price, and SXGA+ projectors have not followed suit. So today, you can get a higher resolution picture, sometimes for less money, from the 1080p format projectors than you can from the SXGA+ models.

Now, we can't really discuss resolution without thinking about aspect ratios. An SXGA+ projector is 4:3 in format, same as a traditional old television. If many of your photographs tend to be square or relatively close to 4:3, you might imagine that an SXGA+ projector would be the best match from a format perspective. Conversely, a 1080p projector is 16:9, which is the HDTV widescreen format. That would seem to be good for wide-format landscape photography, but not so good for portraits and other images that don't have a wide aspect ratio. So which is better for photography, a projector that is native 4:3 or one that is 16:9?

The answer is this: in most cases, the 16:9 format 1080p projector will be the better choice no matter what type of photography you are presenting. The only exception would be if you have a very large venue that demands 3000 ANSI lumens or more of brightness. At this moment in time, there are several SXGA+ projectors which deliver 3000 lumens or more, which is quite a bit more than most of the 1080p products on the market. So if you have the need to sacrifice some resolution in exchange for added brightness, an SXGA+ model might be the best bet. But the ideal solution from a resolution perspective will in all cases be the 1080p projector.

Why is that? Clearly, photographs are made in a variety of aspect ratios. Most smaller point-and-shoot digital cameras, regardless of resolution, have a 4:3 aspect ratio. Not only is this old television standard, but most digital projectors are made in this aspect ratio as well, including those in SVGA, XGA, and SXGA+ resolutions.



4:3 Aspect Ratio of Most Point/Shoot Digital Cameras

If you are a professional photographer shooting medium or large format film cameras, the full frame images will typically be 5:4, or in some instances they could be square.

On the other hand, if you are shooting a digital SLR, that type of camera will normally produce an image with an aspect ratio of 3:2, which as you can see is somewhat wider than the 4:3 image above. This aspect ratio can also be denoted as 15:10, which is not quite as wide as the HDTV 16:9 standard. However, these images can be displayed quite nicely on 16:9 projectors.



3:2 Aspect Ratio of Most DSLR Cameras

Now, how does an SXGA+ projector fall short in displaying these formats? First, let's assume your picture is in 4:3. An SXGA+ projector will show it full frame in 1400x1050 resolution. Meanwhile, a 1080p projector will show it in 1440x1080 resolution, which is an increase of about 6% in the total number of pixels used to create the image. This is not much of a difference. But the important thing to recognize is that, despite its 16:9 format, the 1080p model has a slight resolution advantage over SXGA+ with any image format that is 4:3, 5:4, or anything close to square.

However, let's assume your picture is from a DSLR, and it is in landscape 3:2 format. An SXGA+ projector will show that image in a pixel matrix of 1400x933, which is about 1.3 million pixels. Meanwhile, a 1080p projector will show it in 1620x1080, or 1.75 million pixels. That is an improvement in pixel density of about 35%. That is enough to give your images incrementally more detail than they would have on the SXGA+ projector. The increased pixel density also reduces the potential for visible pixelation in the image, allowing you to achieve a smoother picture.

The bottom line is that, unless you really need exceptional light output, I personally feel that SXGA+ is the less desirable of the two formats as far as photography is concerned, because no matter which aspect ratio your photographs are in, they will always be shown in less resolution on an SXGA+ projector than they will on a 1080p projector. And due to the competitive dynamics of the consumer home theater market, not only are 1080p projectors higher in resolution, but they can be lower in price as well.

Aesthetics of Image Presentation

Having stated my preference for widescreen projectors, there is an aesthetic consideration that must factor into your decision, and your preferences may be different than mine. Assuming you have a mix of 4:3, square, and 3:2 photographs in your collection, you need to ask, "Do I want the 4:3 and square images to look bigger on the screen than the 3:2 images, or do I want the widescreen 3:2 images to look bigger than the 4:3's? Your choice of a 4:3 vs. a 16:9 projector will determine which type of image looks the largest on the screen.

If you choose a 4:3 projector such as an SXGA+, all 4:3 and square images will appear larger than your wider landscape images. The landscape photos will be displayed in the same width, but they will have black bars top and bottom, and the total image size of your widescreen photos will be smaller than your 4:3 images.

Conversely, if you go with a 16:9 projector, your widescreen landscape format photos will appear larger (wider). Meanwhile, your 4:3 and square images will be displayed in the same height, and they will appear in the center of the screen with black pillars on the sides.

There is no right or wrong to this, it is just an aesthetic preference that you may have. If you want your square and 4:3 images to be the largest images on the screen, and if you are willing to sacrifice some resolution of your 3:2 images to achieve that effect, then a 4:3 projector will be a better solution for your particular needs.

Budget Projectors

Though 1080p projectors have dropped below $3,000, and a few models are below $2,000, that is still too hefty a burden on many budgets. If you are seeking a less costly alternative, you can find standard 4:3 XGA projectors (1024x768) and widescreen WXGA projectors (1280x768) for under $1,000. The pixel resolution math works almost the same way. For images that are 4:3 or less wide, these two formats will deliver images with the same pixel matrix. However, with landscape format images, the WXGA projector will have a significant advantage.

Conclusion

Overall, widescreen projectors will give you more pixels to work with than will standard 4:3 projectors. So the 16:9 models made for home theater tend to be the best choices for photography as well. Not only do they have an advantage in physical pixel resolution, they tend to be higher in contrast and better at delivering neutral color balance than are most 4:3 projectors. These issues will be discussed in Part Two, along with more specific evaluations of several widescreen projectors that make our short list of the best choices on the market today for photography.