manual focus help please

[ali_mama]

hi, I'll have the chance to shoot some fireworks after a couple of days (it'll be Eid al-Fitr in the Muslim world where I live) and I diligently read the article on How to photograph firework displays and all the comments after it ( I found both the article and comments very illuminating and precious)...so one of the tips is to set the manual focus to infinity and as I have never ventured into manual mode until now I have no idea how to do that and I didn't find any info on that in the manual either. My cam is Canon EOS 450D - please can anyone tell me how to set the manual focus to infinity? Please, don't laugh, I suppose it's a stupid question but I'm a novice

[OsmosisStudios]

Depends what lens youre using. Chances are its the 18-55 (IS or non doesnt matter).

in this case, set the lens to M on the A/M focus switch (left side of the lens barrel when holding the camera as normal). Once youve got that, you can fiddle with the focus ring which is at the very end of the lens barrel, at the front. Moving it one way all the way will give you the closest focus distance: the other way will stop you at Infinity. Just use your viewfinder to figure out which way is which.

[Doug Pardee]

Originally Posted by OsmosisStudios

the other way will stop you at Infinity.

Are you sure about that? Most Canon lenses allow the focus ring to turn "beyond infinity" to allow for infinity focus under extreme temperatures.

I'd say just pick something really distant, focus on it, and mark your focus ring to show where that is. Then when you're ready to shoot fireworks, switch the lens to MF mode and turn the ring to the mark you made.

[OsmosisStudios]

The 18-55 is one of the few that doesnt, IIRC. I could be wrong and could be thinking of the Nikon version. Curse my retail job...

[ali_mama]

Originally Posted by OsmosisStudios

The 18-55 is one of the few that doesnt, IIRC. I could be wrong and could be thinking of the Nikon version. Curse my retail job...

yes, my lens is the 18-55 and you're right - it doesn't focus beyond infinity. And here's what digital photography review says about the manual focus:
"The manual focus ring is a miserly 3mm wide, and rotates less than 60 degrees clockwise from infinity to 0.25m.
The focusing action can only be described as loose and imprecise (especially noticeable when using magnification in live view). To add insult to injury, there’s no distance scale."

Anyway...

Thanks to both of you for the prompt reply - it was really useful to me!

Second question: I'm short-sighted and though I'm wearing contact lenses I don't see very well too far - so is there something I can attach to the viewfinder or whatever that can help me with the manual focus?

[inkista]

Not really. But the viewfinder has a small wheel next to it that allows for diopter adjustment. You could try spinning that to see if it helps you.

[Marcuscarcus]

if im in autofocus mode, can i turn the focus wheel to tweak the autofocus or is this going to mess up my lense. Does it depend on which lense or is it just a no no.

[ali_mama]

Originally Posted by Marcuscarcus

if im in autofocus mode, can i turn the focus wheel to tweak the autofocus or is this going to mess up my lense. Does it depend on which lense or is it just a no no.

even when the camera is in auto focus mode the lens focusing ring is moving to achieve focus so you should be careful to keep your fingers away unless you disturb the work of the motor...so I guess you're not supposed to play with this ring in autofocus mode...