topic Re: Can't get my camera to focus in EOS DSLR & Mirrorless Cameras

Can't get my camera to focus

Mghnickell — Tue, 15 Aug 2017 22:39:26 GMT

Hi y'all,. I'm new to photoboothing and I can't figure out what setting I put my Canon Rebel T5 on so that everyone stays in focus and don't come out blurry. Can someone please give me some pointers ?

Re: Can't get my camera to focus

diverhank — Wed, 16 Aug 2017 00:29:37 GMT

@Mghnickell wrote:
Hi y'all,. I'm new to photoboothing and I can't figure out what setting I put my Canon Rebel T5 on so that everyone stays in focus and don't come out blurry. Can someone please give me some pointers ?

What are your settings (Av, Tv and ISO) in the pictures that are blurry. How far apart are the rows of people? How far are you (your camera) from the people? What focal length?

Re: Can't get my camera to focus

Waddizzle — Wed, 16 Aug 2017 01:16:00 GMT

@Mghnickell wrote:
Hi y'all,. I'm new to photoboothing and I can't figure out what setting I put my Canon Rebel T5 on so that everyone stays in focus and don't come out blurry. Can someone please give me some pointers ?

Read the instruction manual.

Do a web search for " exposure triangle " , and " depth of field ".

Read the instruction manual again, because you should have gained a better perspective after learning about the above.

Find out why the following common reasons for not being able to focus, can cause the camera to not be able to focus.

Not enough light for the camera to focus. Try enabling the "AF Assist Beam"
Not enough contrast under the AF point for the camera to focus.
Subject is too close to the camera.
Use of an extender raises the effective f/stop too high for the camera's AF system to focus.

There are more reasons, but those are some of the most common.

Re: Can't get my camera to focus

ScottyP — Wed, 16 Aug 2017 10:08:55 GMT

By "photoboothing " do you mean like at a wedding where people climb into a little booth with funny hats and make group selfies?

is the problem that no one in the group is in focus or that like one or two people are in focus but other people who are closer or farther from the camera are out of focus?

As as mentioned you need to know the exposure triangle to understand the problem. It could be several different things including:

-too slow a shutter speed allowing the living moving subjects to show motion blur, or

-too large an aperture (too low an f/number) giving you too shallow a depth of field in focus so individuals closer or farther away even by inches, won't all be in focus, or

-not enough light for autofocus to work at all.

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 16:14:24 GMT

In answer to diverhank's first question , apparently I had it on landscape mode which I guess is an auto feature instead of manually setting my aperture, ISO and shutter speed. Should I manually set this info instead of relying on the camera to make the corrections for me? In answer to you second question,. The people that are in the photo booth either get right on top of the camera or they stand back but don't stand still. I was reading up on the "exposure triangle" last night and saw that tweeking your settings can correct for a little movement. Did I interpret that correctly? The focal length is approximately 4 feet so when they crowd camera it goes seriously out of focus

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 16:19:32 GMT

I saw where both ScottyP and Waddizzle mentioned not enough light as one of my problems. I have an alien bees strobe but when it goes off it lights the subjects up so much they look like they're glowing white . Due to that issue I have just turned it off and are using ambient light that seeping into the photo booth. Any suggestions?

Re: Can't get my camera to focus

jrhoffman75 — Wed, 16 Aug 2017 16:37:19 GMT

A strobe won't help low light focus.

Which lends are you using?

What camera settings?

Re: Can't get my camera to focus

diverhank — Wed, 16 Aug 2017 17:02:38 GMT

@Mghnickell wrote:
In answer to diverhank's first question , apparently I had it on landscape mode which I guess is an auto feature instead of manually setting my aperture, ISO and shutter speed. Should I manually set this info instead of relying on the camera to make the corrections for me? In answer to you second question,. The people that are in the photo booth either get right on top of the camera or they stand back but don't stand still. I was reading up on the "exposure triangle" last night and saw that tweeking your settings can correct for a little movement. Did I interpret that correctly? The focal length is approximately 4 feet so when they crowd camera it goes seriously out of focus

Thank you for the info. Now I feel I have enough info to give you a half-way decent advice (maybe :)).

For a photobooth environment, you should definitely use a Manual setting and not leave it up to the camera system which can be easily fooled.

1. You should definitely use the Alien Bee...you just need to control it so the light output is not excessive (overexposing your picture). This will give you plenty of light to work your settings which will solve lots of other problems.

2. Set the camera to M mode.

3. Set your ISO to some value. For photobooth type quality, I'd set ISO to 800...This will give me flexibility in other two settings without harming the quality of the prints that much. You can vary ISO to your liking, of course.

4. Your camera/lens combo has something called a Minimum Focus Distance so you have to control the environment so the people cannot get too close to the camera...otherwise everything will be blurred. Best is to move the camera back enough behind a glass panel so people can stick their faces right up to the panel without being blurred.

5. I'd set the MF (manual focus) on the lens,manually focus to a spot a couple feet off the glass panel (where people will most likely be) and set the aperture (Av) to something like f/8 or higher. This way your depth of field will be ample no matter where people may end up with.

6. Set your shutter speed (Tv) to 1/200 or faster if your Alien Bee can do high speed sync. This way people moving will not be as blurred.

7. With my proposed setting, there is no way you can get away without using flash/strobe like the Alien Bee. The key now is that once you manually set Av, Tv and ISO, the required amount of light is fixed. You need to set the Alien Bee to manual and adjust the intensity until the faces are properly exposed.

8. If you have ambient light in the booth, you might want to set White Balance to degrees Kelvin. Tweak it so the color looks the best.

8. Tweak the settings until things look perfect. This is a lot easier than taking pictures of people mingling in a wedding...everything in a booth can be controlled.

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 17:53:27 GMT

The lens is a Canon EFS 18-55 mm and it was set on an auto mode for landscape. Im going to try a manual setting and see if I can clear up my issue. I noticed there is an image stabilizer on the lens. Will that help?

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 18:02:09 GMT

Im going to try all your suggestions and see what happens. The only thing I can't do is move the camera. It is actually installed in the photo booth cabinet. What I might end up doing is put maybe a velvet rope inside the booth to discourage people from getting to close. Hopefully that along with your suggests will clear up my issue. If it does, thanks so much for your input. If it doesn't hopefully ya'll wont mind helping me some more.

Re: Can't get my camera to focus

jrhoffman75 — Wed, 16 Aug 2017 18:08:22 GMT

If you can control how close people can get to the camera you could set lens to MF, manually focus lens on location where people are and set camera to Av mode, set lens to f/11. That would give you some depth of field, focus acquisition wouldn't be an issue, and it sounds like your flash has plentiful power to handle f/11.

Re: Can't get my camera to focus

ScottyP — Wed, 16 Aug 2017 18:38:09 GMT

Image stabilization won't help here. All IS does is to counter the effect of your hands shaking as you hold the camera. Since your camera is hard mounted there is no camera shake and you should in fact turn IS off or it may actually cause blur by operating in a firmly mounted camera.

The blur you are worried about is subject movement blur. The only cure against that is a shutter speed fast enough to freeze that action. 1/200 probably covers it but if not try 1/320 or 1/400.

Re: Can't get my camera to focus

diverhank — Wed, 16 Aug 2017 18:41:06 GMT

@Mghnickell wrote:
The lens is a Canon EFS 18-55 mm and it was set on an auto mode for landscape. Im going to try a manual setting and see if I can clear up my issue. I noticed there is an image stabilizer on the lens. Will that help?

Image stabilizer only helps if you're handholding the camera and you shake a lot. In this case, since it sits on a cabinet, IS is doing nothing for you.

The Minimum Focus Distance for this lens is about 11 inches so try to block people from coming closer than that. I'd set the lens FL to 18mm to maximize the Depth of Field. I'd try focusing on a spot roughly 24 inches from the lens and set aperture Av to f/8 or f/11. That should do it. Tweak it so everything can be in focus.

I'll be glad to offer more help if you need it.

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 19:22:19 GMT

Thank you

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 19:50:07 GMT

Ok I'll try that

Re: Can't get my camera to focus

Waddizzle — Wed, 16 Aug 2017 22:49:41 GMT

I seem to recall the old fashioned photo booths having a white line on the floor, which you had to stay behind, otherwise your photos would be out of focus.

I would definitely look to upgrade a faster lens. The T5 does not have good low light performance. I try not use ISO settings higher than 400, due to noise. But, for a photo booth, ISO 800 will probably work, and work well.

If the booth is function unattended, then using a low end DSLR and lens is the way to go.

Re: Can't get my camera to focus

kvbarkley — Wed, 16 Aug 2017 23:15:23 GMT

Actually, using a small sensor P&S would work better because of the DOF. I used to pretty good portraits with my A400.

Re: Can't get my camera to focus

Mghnickell — Wed, 16 Aug 2017 23:47:35 GMT

Dumb question, What is P and S?

Re: Can't get my camera to focus

ScottyP — Thu, 17 Aug 2017 00:08:34 GMT

Point and shoot.

Re: Can't get my camera to focus

Mghnickell — Thu, 17 Aug 2017 00:12:23 GMT

Ok . Thank you