Christmas Lights

[thisbejonas]

Can someone tell me what Im doing wrong. I just cant seem to get a real crisp focus on houses with Xmas lights. And the lights themselves always seem to have a "halo" around them. I am using a tripod. Does someone know if there is a way to force the canon 40D to focus on all its focus points instead of just 1 or 2 points. Thanks for your help

[Japaslavian]

Originally Posted by thisbejonas

Does someone know if there is a way to force the canon 40D to focus on all its focus points instead of just 1 or 2 points.

If it works anything like my Rebel there's two small buttons on the back side towards the upper right. One of them should have a grid shape underneath. If you're in a non-automatic shooting mode, you should be able to press that, and a red light will appear in your view finder on some of the focal points. If you press your arrow buttons (or scroll wheel), you should be able to get each focal point to light up, and you will be focusing on everything. Supposedly.

Not completely sure about the 40d, but give it a try. I'm sure someone who uses the same camera can probably tell you for sure.

[hpebley3]

Originally Posted by thisbejonas

Can someone tell me what Im doing wrong. I just cant seem to get a real crisp focus on houses with Xmas lights. And the lights themselves always seem to have a "halo" around them.

I don't think you have a focusing problem (it looks in focus to me) so much as an exposure problem. I think the issue is you have a high dynamic range in the scene: bright points of light and dark areas. To get good detail in the dark areas, the bright points will be blown out, bleeding over into the adjacent pixels. At f/14 the lights need a shutter speed of probably less than a second and the shadows obviously need 15 seconds.

A couple ideas for "fixing" it:
- Take multiple shots and use HDR software to combine them.
- Take two shots, one properly exposed for the dark area and one for the lights and combine the best of each in post-processing.
- Expose for the lights and in post-processing selectively lighten the dark areas.
- Light the house so you don't have dark areas needing a long exposure. E.g. put a number of flashes pointing up around the foundation or get a couple 10 million candle power spot lights and have some assistants light the house when you take the picture.
- Reduce the intensity of the lights so they don't blow out on a long exposure for the dark areas. E.g. put them on a dimmer and turn them way down.

Hope that helps.

[Major_Small]

Originally Posted by Japaslavian

...you should be able to get each focal point to light up, and you will be focusing on everything. Supposedly.

That's not exactly what's going on there. You're just selecting AF points. When you have all of them lit up, all that means is that your camera will focus on any one of those points. whichever ones light up when you squeeze the shutter halfway down are the ones that are in focus. I think you're getting that confused with your A-dep setting

[thisbejonas]

Originally Posted by Major_Small

whichever ones light up when you squeeze the shutter halfway down are the ones that are in focus.

Thats what I was thinking but is there a way to force all the points to light up at once?

[Major_Small]

Originally Posted by thisbejonas

Thats what I was thinking but is there a way to force all the points to light up at once?

If you mean getting all the points in focus, yes, just make sure they're all on the same plane parallel to your sensor, or use the A-dep setting and set your aperture accordingly. Barring that, you can always try bending the fabric of space-time to your will... but good luck with that

< insert a bunch of babble about how to get a higher f-stop, then delete it because I was too stupid to check your EXIF data first >

edit: actually, looking at your EXIF data, you shot that at f/14... that's already pretty closed down >.<

okay, next suggestion... post-processing. Have you tried sharpening in photoshop or another similar program?

[clockdoc]

Good advice provided by others. One other key to successful light shots is to start shooting earlier in the evening when there is still some light in the sky, about 20-30 minutes after sundown. Start taking shots about every 30 seconds and check the results on your LCD. When the balance is there, shoot like crazy using equivalent shutter speed/aperture combinations and refocusing between shots as the time window is limited before the sky becomes too dark.

[Thinking_Mommy]

Im jealous...I can NEVER get decently clear shots of Christmas Light!

[thisbejonas]

Originally Posted by Major_Small

okay, next suggestion... post-processing. Have you tried sharpening in photoshop or another similar program?

Well Im not any good with editing at all, I have gimp but have yet really learned how to mess with layers and such. Would anyone be willing to do a quick touch up job on my photo so I can see the difference and also maybe point me to a good sight to learn more about gimp from a beginers level. Thanks

[Major_Small]

here's my attempt. Keep in mind I'm no post-processing whiz. I'm sure others could do much better with this:

here's a little bit about how to use the unsharp mask: http://docs.gimp.org/en/plug-in-unsharp-mask.html

I used 0.1, 0.75, 0.0 as my values, and bumped up the brightness and contrast by a little bit (I think it was something like +60 brightness and +30 contrast).

A side note, it looks like you might have a hot pixel in there. It's not the easiest thing in the world to spot in the original, but if you take a look at the full-sized version of my edit (http://img20.imageshack.us/img20/636...arpeneduv4.jpg) you can see it just to the left of the house in the top of the tree. It's bright blue. I'm not actually sure if it's a hot pixel or not, but that's my guess.

In the full-size version, you might also notice that with that sharpening I introduced noise into the image. If this were a professional shoot, I don't think that'd be acceptable, but as it's 230am and I only really intended to post the scaled-down version, I let it slide >.<

Also, out of curiosity, I see you list a circular polarizer in your sig. were you using it for this shot?