Being still a complete beginner on this i need some help. Ive done a bit of reading up on this and think im more confused now than i was to start off with.

Im after a new lens (to replace the kit lens 18-55 on my 350D), I tend to shoot more indoor shots than anything else and find the kit lens pretty rubbish with no flash, and even with the flash its hit and miss (although im 100% certain this is due to my lack of ability)

Now my first thought was to get an F2.8 lens as this should allow me to shoot in less light and not get blurry hand held shots as the shutter speed can be quicker. Where my current lens is at F4 and say 1/60 with a 2.8 lens (1 stop quicker?? hope im getting this right) my shutter speed would be 1/125? so this is good :) .

Now ive just read the dpreview of the 400D and it says the middle AF point of the new 9 point AF system is F2.8 capable, does this mean my 350D is not? and if so does this mean F2.8 lenses are not an option for me anyway?

But then i stumbled across some Canon text about IS and how it can improves the camera (whats the right phrase here?) by 3 stops, now surely for my type of shooting getting a F4-5.6 lens with IS is going to be much better than an F2.8 lens. As it give me 3 stops of improvement as opposed to the 1 or 2 the F2.8 with give me over the F4-5.6?

would really appreciate your thoughts or experience on this.

Cheers.

Mark

Your best bet might be to get a better flash than the one that's built into the camera. You could get, say, a 430EX and bounce it off the ceiling, which would give you natural looking light at 1/250 sec or thereabouts, which would certainly be sharp.

IS is a wonderful thing provided your subject isn't moving - it can compensate for camera shake, but not subject motion.

You can certainly use an f/2.8 lens on your 350D. I don't honestly know what they mean by 'f/2.8 capable' on the 400D - probably the AF points become faster or more accurate for some reason with an f/2.8 lens. All other things being equal, a wider aperture is always better for focusing than a smaller one.

You don't mention a budget, but getting f/2.8 in a zoom lens is going to be expensive. Your best bet might be the new EF-S 17-55mm f/2.8 IS USM which gives you both f/2.8 and IS as well, but it's about £750 and will only fit recent DSLR cameras with an EF-S compatible mount. If that doesn't appeal, you could go for a prime lens, say the 50mm f/1.4 @ £250ish, or the inexpensive but optically excellent 50mm f/1.8 mkII @ £80.

On 400D its just accuracy or speed, it will function fine with f2.8 or above lenses.

A 50mm f1.8 is very affordable and is excellent in low light.

You need to remember that IS only gives you upto 3 stops improvement in exposure by cancelling, or reducing , the amount of camera shake and vibration as you take the photograph, and not an equivalent shutter speed of +1,2 or 3

So, theoretically, your photographs taken at 1/15 sec should contain the equivalent amount of camera movement as one taken at 1/125. BUT if the subject is moving, no amount of IS will give you a sharp subject at 1/15.

If you have a f2.8 lens then at least you have the extra stop as you rightly mention - this may be enough to prevent subject motion blur if you are now shooting at 1/125 instead of 1/60 @ f4.

Ideally you need f2.8 and IS :D

PS - Sorry Andy, just realised you mention this characteristic in your post, must learn to read posts fully and not scan :)

Before shelling out on new lenses or flash units, try experimenting with iso settings. The newer breed of DSLR's do not add significant noise at the higher settings.

The new sensor on the 400D is leaps and bounds ahead of the 300D when it comes to noise reduction at high iso. I have a couple of 1600 ISO that look as good as 200 ISO on the 300D in print. :)

By indoor shots, do you mean portraits? I use my 50mm f/1.8 for that and it's great.

Now ive just read the dpreview of the 400D and it says the middle AF point of the new 9 point AF system is F2.8 capable, does this mean my 350D is not? and if so does this mean F2.8 lenses are not an option for me anyway?


would really appreciate your thoughts or experience on this.

Cheers.

Mark

Mark,

What that means is that the 400d (like the 20D and 30D) has a centre AF sensor that is in laymans terms more accurate (to within 1/3 of the focus plane as opposed to 1 x the focus plane) when using lenses which are f2.8 or faster.

The outer AF sensors are accurate to (i think) 1x the focus plane regardless of the lens used within the af operational range.

Basically, using the centre AF point with a lens of f2.8 or faster should result in more accurate focus.

I use an f2.8 and f4's on my 20d, and I would say that the 2.8 does probably produce a higher percentage of shots with the focus bang on.

HTH

Thanks for the great replies. Andy and Gareth it didnt even occur to me about subject movement but now you have explained it, it kind of puts a 'negative' against the IS feature. Especially with active subjects like kids and dogs :)


You don't mention a budget, but getting f/2.8 in a zoom lens is going to be expensive. Your best bet might be the new EF-S 17-55mm f/2.8 IS USM which gives you both f/2.8 and IS as well, but it's about £750 and will only fit recent DSLR cameras with an EF-S compatible mount. If that doesn't appeal, you could go for a prime lens, say the 50mm f/1.4 @ £250ish, or the inexpensive but optically excellent 50mm f/1.8 mkII @ £80.
Budget wise im looking at £400 tops, and probably a bit lower if i can get away with it.

The two lens ive seen so far are the
Tamron 28-75 F2.8
Canon 17-85 IS F4-5.6
I was thinking along the lines of, the tamron gets a few good reviews so would be a good relatively cheap way to play with F2.8, if it still doesnt work for me I could sell it on and try the IS lens instead and if that doesnt work well ill have to sell the wife then and get an F2.8 with IS :norty: .


Ideally you need f2.8 and IS :D

and ideally a budget to match it :(

By indoor shots, do you mean portraits? I use my 50mm f/1.8 for that and it's great.
Yeah standard indoor stuff really, kids, dogs, parties etc etc.

or the inexpensive but optically excellent 50mm f/1.8 mkII @ £80.

Haveing just re-read my post it seems i was missing a glaringly obvious cheap way to play with a low F number lens.

Might just pick one of these up for a play and see how i get on.

Mark

Here you go - the superior mk I version with the metal lens mount: eBay.co.uk: Canon 50mm F1.8 Mark ONE. Very rare and like new! (item 320038214948 end time 19-Oct-06 17:27:58 BST) (http://cgi.ebay.co.uk/Canon-50mm-F1-8-Mark-ONE-Very-rare-and-like-new_W0QQitemZ320038214948QQihZ011QQcategoryZ4687QQ rdZ1QQcmdZViewItem)

F2.8 isn't much better for indoor shooting than f4 really, so if you do a lot of that stuff then primes are your best bet. Trouble is, a 50mm lens on a 350D won't give you many options indoors, other than head and shoulders portraits.

There are plenty of decent primes about, as they are much easier to make than zooms. For £400 you should be able to buy 2 or 3 decent ones, especially if you don't mind secondhand or third party brands :)

Here you go - the superior mk I version with the metal lens mount: eBay.co.uk: Canon 50mm F1.8 Mark ONE. Very rare and like new! (item 320038214948 end time 19-Oct-06 17:27:58 BST) (http://cgi.ebay.co.uk/Canon-50mm-F1-8-Mark-ONE-Very-rare-and-like-new_W0QQitemZ320038214948QQihZ011QQcategoryZ4687QQ rdZ1QQcmdZViewItem)

thanks its on my watch list.

Mark

F2.8 isn't much better for indoor shooting than f4 really, so if you do a lot of that stuff then primes are your best bet. Trouble is, a 50mm lens on a 350D won't give you many options indoors, other than head and shoulders portraits.

There are plenty of decent primes about, as they are much easier to make than zooms. For £400 you should be able to buy 2 or 3 decent ones, especially if you don't mind secondhand or third party brands :)

Thanks for the advice, think im going to go with the 50mm first and see how i get on. but as you say 50mm on a 350D is a bit long for indoors, so ill try it out and see how it goes. As you say i can always pick up a shorter prime later on.

Or if i find the it a pain changing lenses all the time will have to comprimise on F number and get a zoom.

Cheers again.

Mark

For the kind of stuff you're shooting, this might do the trick:

Wind up ISO as necessary, set camera to Av, lens wide open and pop up the flash.

You will get good even exposures with flash illuminating the foreground and freezing movement, while the camera balances the background ambient light. I use this a lot and have some really great family snaps. The downside is that you can get ghosting when flash and ambient light are mixed with a fast-moving subject, but sometimes that actually enhances the images. Other times, it can ruin it :(

Worth a try. And cheap :D

Richard.

You've got to be careful with the flash... you can ruin some good shots with harsh lighting.

You've got to be careful with the flash... you can ruin some good shots with harsh lighting.

Agreed. But that's the advantage of fill-in flash as suggested above - the balanced ambient light helps to open up and soften any harsh shadows the flash might create ;)

Richard.