Focusing Tips?

[Canon88]

Hey everyone,

I use a canon rebel xt and I'm having some difficulty focusing my lens manually during low-light exposures. Because of the low lighting, it is always difficult for me to see if a subject is exactly in focus; any suggestions?

Please do not mention the diopter, better lighting conditions, or live-view, a feature my camera does not have. Also, I do use manual focus because for auto-focus to work you generally have to have some kind of contrast for the lens to go off of, which I usually do not have in low light, and even if I did, I would still rather trust manual focus.

Below are two images on a six second exposure --- the first one I thought was in focus, but obviously is not. Because of the available light I only waisted six seconds... but what if my exposure required a minute or two? I'd rather get the focusing down the first time; hence I'm writing this.



versus the in-focus version as seen here:

[phillip ino]

Was there any wind at all?

[Canon88]

Originally Posted by phillip ino

Was there any wind at all?

None.

[snidow]

The only thing I can think of is to use a source of light to be able to focus on the subject in low light conditions. Like a flash light or something, I've had to use one before at night to focus.

[JohnT]

Originally Posted by snidow

The only thing I can think of is to use a source of light to be able to focus on the subject in low light conditions. Like a flash light or something, I've had to use one before at night to focus.

This is exactly what I was thinking, and I have done this as well.

[toverman]

You were probably using a tripod, but if not, that would solve part of the problem.

Using a flash to help you focus and then turning it off sounds like it's worth a try, though.

[Dobick]

One thing that I find that helps me in these types of situations is to pick out a spot and adjust the focus until that one spot is most in focus. take the scene you posted above as an example. I would pick out the smallest detail in the tree that I could see, and manually focus it in to the point to where it was most sharp. I know that is pretty much the definition of focusing, but the point that I am getting at is that it helps sometimes if I remind myself to pay particular attention to it.

Another thing that no one has mentioned is to walk off the distance between the camera and the subject, and then use the focus distance guide on the lens if it has one.

[CincoJoe]

What lens are you using?

[kronos2818]

As I look at the two photos, I am thinking maybe a little camera shake might be the cause not out of focus. You said you were using a tripod, but even in a tripod any slight viberation on a 6 second exposure may give you that effect. If the tripod is not solid on the ground the shutter opening and closing can cause enough vibtration to blur your photo...

[douge]

You need a good flash light. I use a Husky re-chargeable (Model HSK117S). It is a million candlepower and it has been invaluable when I am shooting in the evening and at night. I use it to do some light painting on the home or building. I hope this idea will help you in focusing those pesky branches in low light.
Good luck.
Doug

[venchka]

I do hope you solve the problem. Once upon a time, auto-focus cameras had an infrared focus assist beam. Then they moved the beam into the flash. Now you have to spend $300-$400 for the flash to get the assist beam.

Meanwhile, back at the ranch, another giant leap backwards for modern cameras. You can Chimp on the little TV screen but you can't focus the silly things. But, since you can Chimp, you know the camera wasn't focused. Didn't somebody write a book about these things?

[TxManx]

I bought an STE-2, specifically for this purpose...

it's also a remote trigger for other Canon speedlights...

Ken