Focusing question

I could sure use some advice when it comes to focusing for taking pictures of fireworks. I've always enjoyed taking pictures of fireworks, & have worked hard through the years to learn everything I can about taking good pictures of fireworks. I really felt like I had this down to a science! For the past few years, I've used my d7000 & nikon 18-105mm lens. Focusing hasn't been an issue until this year when I decided to use my new tokina 11-16mm lens. I really seem to be second guessing what has always worked for me in the past.

With my 18-105mm I usually wait for the 1st burst, half click in auto focusing, & then switch over to manual focusing on the lens & camera. The end results are pretty tack sharp. However with the tokina unlike the 18-105mm, it has an infinity marking. I know at least with my tokina right in the middle of the infinity symbol is pretty tack sharp. As I also do a lot of night photography, stars/star trails, so I've played around with manually focusing on stars, & the middle of the infinity symbol seems to be tack sharp on my lens.

This is probably a silly question, but is there really any difference between focusing either way, or is it a matter of preference? Whether I focus manually, & rock the focus ring back & forth to get sharp focus... or simply move the ring to the infinity marking, verses using the auto focus half click & switch to manual when I have sharp focus?

At one of our local displays tonight, I set the focus ring on the infinity symbol, and took pictures this way for about half the show, & then I worried that maybe it wasn't in sharp focus. So I turned on my live view zoomed in & began to rock the focus ring back & forth. I quickly learned that this was not as easy as it is with focusing on the stars in the night sky, where as you have plenty of time to get sharp focus. The fireworks on the other hand are constantly moving, and are bright one second & gone the next. So I quickly switched back to auto, half clicked on a burst & switched back to manual.

I haven't got my pictures onto my computer yet to really look at them. But I know there are many of you who enjoy taking pictures of fireworks as much as I do, so I figured if anyone could help me to better understand, it would be here.

On a side note, I find taking pictures of fireworks at Disney much easier, because I have the castle I can focus on beforehand. But with this specific display it's pretty much complete darkness before the show starts with an occasional car's headlights passing by. So nothing really to focus on before the show starts.

This is a general answer; just set the focus to manual/infinity and click away.

I say general because you'll almost always be far enough away from the fireworks for your lens (at a particular f-stop) to render the fireworks sharp when set to infinity. There are exceptions, as some lenses might prefer to be a bit "less" than infinity. Also, you might want an "artistic" shot with something in the foreground (or not as far away as the fireworks) in sharp focus with the fireworks of lesser sharpness.

kgreen said:

On a side note, I find taking pictures of fireworks at Disney much easier, because I have the castle I can focus on beforehand.

Click to expand...

You might be surprised how much further away the fireworks are from the castle.

OKW Lover said:

This is a general answer; just set the focus to manual/infinity and click away.

I say general because you'll almost always be far enough away from the fireworks for your lens (at a particular f-stop) to render the fireworks sharp when set to infinity. There are exceptions, as some lenses might prefer to be a bit "less" than infinity. Also, you might want an "artistic" shot with something in the foreground (or not as far away as the fireworks) in sharp focus with the fireworks of lesser sharpness.

Click to expand...

Okay, Yes that makes sense. Thanks for your quick response! We go to 3 local displays every year. The 1st is in a small town behind the ball field and we are pretty close to where they are shot off. The 2nd is in the country shot over a bridge. We sit pretty far off in a valley. And we have 1 more display in our town this evening. We sit pretty far away and I can include more things like people, buildings & cars passing by. So each are a little diffrent.
After thoughts, now that I have the option of these 2 lenses. I think the wide angle might be better for the display that I can get in closer to. And my 18-105mm may be better for the displays that are further away. I feel like the wide angle lens was a bit to wide.
Also thanks for the advice about the fireworks being further from the castle than I thought. Next trip I'll play around with my focusing. As my goal is to have the fireworks in focus, but also keeping the castle in good focus as well. Thanks again!

Our next trip to Disney is for Mnsshp, so I'm excited to take pictures of the halloween party fireworks. This will be my 1st time taking pictures of the fireworks during the party. I've done Wishes & Illuminations a couple of times. I'm excited to see how diffrent they are.

There is a difference, and how big it is depends on Canon vs Nikon, and I vs II lenses. Because it uses SD glass, it will not always be sharp at that mark on the focus ring, it varies with temperature (this is also why it will focus past infinity). Additionally, the clutch mechanism that lets you put it in and out of AF/MF on the lens is problematic and will cause the focus to move after switching it.

The, "Best," compromise is probably to use back button AF, so the lens stays in AF mode but does not AF unless you tell it to. Also, stop it down to f/11 and the DoF will keep everything in focus, too.

Yes I know what you mean about the clutch mechanism. On my 18-105mm it was a simple switch of a button. The tokina you have to pull back on the focus ring and it can be problematic. As long as I've had my camera, I've never really used the Af button thats on the back of the camera? So I'm not sure how that works?

kgreen said:

Yes I know what you mean about the clutch mechanism. On my 18-105mm it was a simple switch of a button. The tokina you have to pull back on the focus ring and it can be problematic. As long as I've had my camera, I've never really used the Af button thats on the back of the camera? So I'm not sure how that works?

Click to expand...

Conceptually it's pretty simple: when enabled, the camera will only AF when you push the AF-On button. What this means in your case is that you can focus and leave it at a preset focus distance, but it also makes switching between AF-S and AF-C instant: simply either hold down or release the AF-On button.

Here's a couple quick primers on it, and there's tons of info on the web about it. It does take some getting used to though, about 1-2 days worth, but once you have learned it, you won't go back.

http://www.learn.usa.canon.com/resources/articles/2011/backbutton_af_article.shtml
http://nikonrumors.com/2014/01/25/how-to-use-nikons-af-on-and-back-button-autofocus.aspx/

jec6613 said:

Conceptually it's pretty simple: when enabled, the camera will only AF when you push the AF-On button. What this means in your case is that you can focus and leave it at a preset focus distance, but it also makes switching between AF-S and AF-C instant: simply either hold down or release the AF-On button.

Here's a couple quick primers on it, and there's tons of info on the web about it. It does take some getting used to though, about 1-2 days worth, but once you have learned it, you won't go back.

http://www.learn.usa.canon.com/resources/articles/2011/backbutton_af_article.shtml
http://nikonrumors.com/2014/01/25/how-to-use-nikons-af-on-and-back-button-autofocus.aspx/

Click to expand...

Wow! Thanks! That will take some time to get use to, but will be very useful!

I played around a bit today and with my tokina it still seems tack sharp right smack in the middle of the infinity symbol. So I set it to infinity and looking through the pictures of tonight's firework display, they are really good and very sharp! And I had said that I felt like the tokina may have been a bit too wide.... not at all! I really like the extra wide path. It gives me a lot of room to crop in horizontal from the original vertical position. Even cropped in quite a bit, the fireworks are nice and sharp! Thanks again for all your help!