My Dad is thinking about upgrading from a small compact to a proper SLR in the fairly near future. He's set his sights on a Canon 40D, but is having a bit of trouble with lens selection. In particular, he takes a lot of photos of bits of furniture after the piece has been installed in a customer's house, so a lens with pretty decent wide-angle features is important, however, it still needs to cover the other basis (ie we're talking an all purpose lens rather than a specialist one).

The part that's left me bloody confused is the full-frame (or not) issue, and the difference on focal length that these give either the AF or AFS lenses. He's got about £400-500 to spend on the lens, can anyone make some recommendations, and possibly explain to a luddite like me the difference please? From what I can gather, sticking an AF lense on a non-full-frame camera alters the focal length, so a 28mm effectively becomes a 35mm.

Canon always spec. lenses in 35mm equivalent focal lengths, be it EF (suitable for any EOS SLR) or EF-S (small-sensor D-SLRs only), so the EF-S 17-55 f/2.8 at it's widest setting will be exactly the same focal length as the EF 17-40 f/4L. Because the sensor is smaller, and so only uses the central portion of the lens (effectively cropping the image), the "effective" focal length is 1.6x the stated value (27mm using the 17mm example above). Nick's written a pretty good article explaining this in more detail.


When you talk about "the other bases" what sort of things do you mean? What sort of things does your dad take photos of? One of the great things about D-SLRs is that they are highly customisable tools, and, personally, I reckon it's best to just get it to do what you want. Also, has he considered getting the 550D instead of the 40D? I know it's an entry-level body compared to the "serious-hobbyist" 40D, but it's newer, more compact-like in size, and HK gets fantastic images from her 400D.

As for lenses, as stated above, it massively depends, but for wide-ish to normal I'd possibly consider the 17-40 f/4L (which I love), but I've just looked and the price seems to have increased since I bought mine a few years back, and maybe a nifty-fifty. Once we know more about what he wants to take photos of, and whether this is something he wants to invest in over time (rather than splashing a bit of cash and then being done with it), I'm sure the lens recomendations will come. I like the reviews on The Digital Picture (He also has a "Lens Recomendations" section), and EF Lens.com is useful when researching too, as it lists all of Canon's lenses with links to specs and reviews.

I'd go with Edd's suggestion and look at the 550D with a kit lens to start with.

The 17-55 kit zoom is an adequate starter lens, and when funds permit you could consider other lenses depending on what sort of photography your father wants to get into.

You'll read a lot about crop factors and stuff. Essentially, most of the baby Canon DSLRs have a smaller sensor than a full 35mm frame, giving in effect a 1.5 or 1.6 time enlargement. EF-S lenses are designed to work with the smaller sensor, and are "calibrated" to offset the crop factor. If you go for EF lenses, the effective focal length needs to be multiplied by the crop factor, so an EF 35mm prime lens gives you an equivalent 55mm field of view on the crop factor camera.

It sounds complicated, but it's not really. Get the camera, read the manual, take loads of pictures and learn how it works. Then worry about other lenses and stuff.

Hey Jon

EDIT: Edd has explained so I won't bother

EDIT 2: Heather has backed up what Edd has said so what is written below is now redundant

EDIT 3: I know - buy a Nikon

There are a few (Canon) lenses within your dad's budget and probably more third party lenses like Sigma, however, the focal length of even the cheapest (kit lens - Canon EF-S 18-55mm f3.5-5.6 IS Lens £147.89 at Warehouse Express) is 28mm in the equivalent of 35mm format. Heading towards the upper limit of the budget (Canon EF-S 17-85mm f4-5.6 IS USM Lens £384.99) is 27mm-136mm equivalent but still falls short in terms of how much of the room can be photographed around the furniture. Edd is right though - the 17-40mm would be the better lens to get. I have the 17-85mm and my copy is reasonably sharp but you can see the difference in results between it and the 17-40mm

Al

Apologies for breaching my self-imposed 1ppd ban, but I feel the need to correct this. All Canon lenses state focal lengths in 35mm equivalent format (ie. actual focal length - remember it is only the field of view that is reduced by using a smaller sensor - all other properties of the focal length remain (depth of field, etc.)) regardless of whether they can actually be mounted onto a 35mm body.

See this pdf (columns 2a & 2b) for confirmation.

http://nickminers.com/ffs

:-D

(8-p)

That kind of makes sense, but the PDF just confirms what I said, really.

For example: 28mm prime on an APS-C (1.6x crop factor) camera equates to a 45mm prime on a 35mm camera.

It's just a spot of mental arithmetic you have to make when you choose a lens. Now, since the EF-S lenses won't work on a full frame camera, I wonder why Canon don't quote the real APS-C focal lengths on the lenses as opposed to the 35mm figure. Seems odd, and has royally confused me from day one.

Right, I think I'm starting to get somewhere here.

With regards to "other stuff", it's mostly going to be things of the level of holidays /touristy things (and our wedding in the summer )

At the moment it's more a case of wanting a good general purpose zoom lens that is at the wider-angle end of the spectrum.

With regards to the body, larger is better as, like me, my Dad has pretty large hands. He also has an option on a well priced second hand model.

Apologies, Heather. I thought you were saying that to compare an EF & EF-S lens you should multiply the EF lens' focal length by 1.6, and not the EF-S lens'.

Edd

Oops - missed that. Thanks Edd!

I have a Canon 10-17mm lens for my 40D. It’s on the camera a lot.

That's the tricky bit. Most general purpose zooms don't go much below 17/18mm or so, apart from the odd pro-level lens that goes to 16mm with price tags to match. I'm not a Canon user so can't comment on their lenses specifically, but I do have a Sigma 10-20mm which does exactly what your dad will need i.e. enable him to get a decent shot of a 'built-in' when he's backed into a tight spot.

I know we're drifting into the realm of 'specialist' lenses here, but sometimes it's what you need - and if you need it regularly, then it's worth the money. I bought mine for exactly the same scenario as your dad (sounds like we do similar work) e.g. this picture was shot through a doorway across the hallway of a standard terraced house i.e. from about 5 feet away. Yes, there's some barrel distortion at the edges (no surprise on a lens this wide) but it's easy to correct if it offends, and without a lens that wide you simply wouldn't get the shot.

Don't know what the current prices are, but I paid about £450 for mine a few years ago.

HTH Pete.

While I certainly can't add anything to the comments above about crop factors and so on what I will say is certainly don't be afraid to have a look outside the canon range at other manufacturers lenses.
If your Dad is more interested in the wide end of the zoom range then Sigma and Tamron both do lenses in the 10 - 20/10 - 24 mm range that are within the budget you are looking at.

Tamron 10 - 24 mm f3.5 - 4.5 Di...

Sigma 10 - 20 mm F3.5 EX DC HSM
or slightly cheaper:
Sigma 10 - 20 mm F4.0 - 5.6 EX DC HSM

Canons equivalent lens is a bit over budget new although second hand would also be an option. Otherwise you are looking at something starting at 17 or 18 mm. Happy hunting.

+1 for Sigma.

I own two of their lenses (28-300 zoom and 10-20 zoom). To be honest, both have their limitations, but they're built like Russian tanks, and weigh the same! I was recommended Sigma by a nice man in a Jacobs store, who let me compare both Tamron and Sigma side by side on my camera body. The Sigma won because it had a metal lens mount, and faster autofocus.

I find the 28-300 a little soft overall, and really needs a sturdy tripod if you're doing anything at the extreme end of its range. The softness can be sorted out in post-processing, to a degree.

The 10-20 is an amazing bit of glass, but its very wide angle nature sometimes throws the autofocus for a loop. While it would seem an ideal lens for indoor work, it's not very bright - ƒ/4 wide open – so if there's not much light about it's not easy to use.