Group Shot - F Stop

JamesU2005 · 2 Dec 2012 at 20:03

Shooting a group shot for my office photo this week.

Taking a photo of about 30 people with a Canon 450D + Sigma 17-70mm. They will be about 8ft away from camera. Thinking maybe two rows of people to fit everyone in.

What sort of F-Stop should I shoot at to get everyone in focus?

Should I focus on a person in the centre front row?

Thanks

King Damager · 2 Dec 2012 at 20:12

F8 would probably do it. If you just need to make sure you get everyone in, and not care about anything else, just shoot it at f22, or whatever the highest you can go.

kd

AHarvey · 2 Dec 2012 at 20:14

http://www.dofmaster.com/dofjs.html

probably looking for around 3-4ft in focus.

so it depends what focal length you are shooting.

17mm + f/8 @ 8ft = Near limit 3.52 ft
Far limit Infinity
Total Infinite

70mm + f/8 @ 8ft = Near limit 7.45 ft
Far limit 8.63 ft
Total 1.18 ft

Big difference

PistolPete · 2 Dec 2012 at 20:15

http://www.dofmaster.com/dofjs.html
Use that to work it out based on whatever focal length you'll be using.

As a rough guide you should focus about 1/3 of the way in as the focus is usually 1/3 in front of the focus point and 2/3 behind.

JamesU2005 · 2 Dec 2012 at 20:51

So around F8 seems to be the common opinion.

Might have to bump up the ISO depending upon the light, otherwise people might be a bit blurry me thinks.

Do you think I can get away with lower than F8?

Focus on the front row then?

Paul11 · 2 Dec 2012 at 20:53

it also depends how far you are from the group

and the distance between the first line and second line of people

a1ex2001 · 3 Dec 2012 at 08:33

JamesU2005 said:
So around F8 seems to be the common opinion.

Might have to bump up the ISO depending upon the light, otherwise people might be a bit blurry me thinks.

Do you think I can get away with lower than F8?

Focus on the front row then?

If it is inside I'd go with a flash or two so you can use f8+ and keep a nice fast shutter.

Nexus · 3 Dec 2012 at 10:11

I'd also add in here that the critical sharpness of the lens is a factor. You could just use f/22 for front to back sharpness, but that might not be the sharpest aperture that the lens offers. Something like f/11 might be far better.

londonbairn · 3 Dec 2012 at 12:11

You should get a DoF calculator on your phone, it's very useful to think along those lines and understanding why to choose a particular aperture, rather than using what has been suggested to you, as Aharvey is outlining.

Nexus is also right - understanding where your lens is sharpest by focal length is also good to know.

apeksdiver · 3 Dec 2012 at 12:20

Most sigmas seem to be best in the middle of their aperture range.

alexthecheese · 3 Dec 2012 at 14:58

I have read (and only read) that a lens performs best 3 stops from either extreme of it's apertures. Nice little rule, if it's right.

PistolPete · 3 Dec 2012 at 18:52

That's a bit of a generalisation I would expect as different lens can perform differently.

My 70-200 f/2.8L IS II is sharpest at f/3.2 and my 24-70 f/2.8L I is sharpest at f/4.5 then both get worse to f/22

Scam · 4 Dec 2012 at 18:53

rafster said:
You should get a DoF calculator on your phone, it's very useful to think along those lines and understanding why to choose a particular aperture, rather than using what has been suggested to you, as Aharvey is outlining.

What's a good DoF calc for Android?

londonbairn · 4 Dec 2012 at 19:35

I have dof calc by raimen ag and I also have the canonsg app as well as it has some cool calculators and some amazing lens porn

An Exception · 4 Dec 2012 at 19:54

JamesU2005 said:
Shooting a group shot for my office photo this week.

Taking a photo of about 30 people with a Canon 450D + Sigma 17-70mm. They will be about 8ft away from camera. Thinking maybe two rows of people to fit everyone in.

What sort of F-Stop should I shoot at to get everyone in focus?

Should I focus on a person in the centre front row?

Thanks

If you can find a way to get more distance between you and subjects so you have to zoom in, you will probably be able to shoot that lens wide open.

I do family group shot's with an 85mm lens@ f1.4, admittedly it was only single file, but either f2 or 2.8 would be fine for two rows.

englishpremier · 6 Dec 2012 at 08:25

PistolPete said:
http://www.dofmaster.com/dofjs.html
Use that to work it out based on whatever focal length you'll be using.

As a rough guide you should focus about 1/3 of the way in as the focus is usually 1/3 in front of the focus point and 2/3 behind.

I've seen this rule around many times now.

How do you focus 1/3 in front of the focus point though? Presumably you have to go manual as oppose to auto focus, but then you actually need something their to focus on.

apeksdiver · 6 Dec 2012 at 08:36

You could try focussing in live view. On all Canon dSLR’s with live view, the depth of field preview button will engage in live view to show you on the camera LCD the exact amount of depth of field you’ll get given the aperture you’ve chosen.

An Exception · 6 Dec 2012 at 08:45

englishpremier said:
I've seen this rule around many times now.

How do you focus 1/3 in front of the focus point though? Presumably you have to go manual as oppose to auto focus, but then you actually need something their to focus on.

Just focus on the person closest to you.

englishpremier · 6 Dec 2012 at 15:54

That's not really focusing 1/3 in front of the true focal point though.

I find it easy to do in landscape shots as there is usually something to focus on, and then you know you're going to infinity.

It's much harder in doors and with people.