What does "28mm equivalet" mean?

Question

I have a film camera that I use for taking real estate picutres. It has a 10mm lens. The wide angle is great for taking pics of interior rooms. I want to buy a digital camera with wide angle capabilities, but I need some advice. If I get an SLR with an 18mm lens, will I actually get that much angle, or just 28mm of angle, or as the product info says, "28mm equivalent?"

Answer 1

Wow, Skipper, you are not going to come CLOSE to your 10 mm lens without spending some major bucks for a full sized sensor like the Canon 5D that Jim mentioned. Maybe your film camera is a Canon so the lens might work (it depends) and at least you wouldn't have to buy a lens. The thing is, the 5D costs almost $3,000 for the body alone. This is a great camera, but I doubt you are looking to spend that kind of money for your purposes.

You are exactly correct in your understanding of the term "equivalent" in describing the lens. With a typical DSLR, there is a "lens factor" or "crop factor" of 1.5X or 1.6X, so multiply the actual focal length of your lens by that factor and you will see how the lens performs compared to the lenses you are accustomed to using on a 35 mm film camera. Your 10 mm lens would act like a 16 mm lens on the under-$1,000 Canon digital SLR's for instance, if it's a Canon lens or 15 mm on a Nikon dSLR.

In the real world, many real estate pros use a wide angle point and shoot camera which costs under $3-400.

I'm not a huge fan of the camera, but the widest angle I know about in a small, easy to operate camera is the Kodak V705. I say that I'm not a fan, because you won't get extremely high quality images from the wide angle end, which is fixed at an equivalent of 23 mm. We both know that you are not going to try making any photographic quality, poster-sized prints, though, and the camera will do just fine for your needs. In fact, if you don't do any cropping, you might even be happy with prints as big as 8x10.

http://www.steves-digicams.com/2007_reviews/v705.html

My top choice in a point and shoot for indoors would be the Canon Powershot SD800-IS (IS may help in low light) which goes to an equivalent of 28 mm on the wide end.
http://www.dpreview.com/reviews/canonsd800is/
http://www.steves-digicams.com/2006_reviews/sd800.html

Answer 2

Nikon may have just the thing: a 10.5mm fisheye. The images can be converted to rectilinear (straight lines) with software, giving a very wide view.

As another poster pointed out, the Canon 5D has a full-frame sensor, so the angle of view is the same as a film SLR, but there are no 10mm lenses for full-frame SLR's (other than fisheyes). There are for regular DSLR's, but that makes them equivalent to 15mm.

Answer 3

Digital cameras have sensors that crop the image. This makes it appear like it's zoomed in. Commonly like 1.5x, so it's common to translate this make to 35mm equivalents.

A Canon 5D has a full size sensor, so no adjustment is necessary. Thus with a 5D, it's easier to get the wide angle shots you desire.