help with AF

[ivans75]

Hey guys, happy new year. Been awhile since last time I posted here. I need some help with focus please. Particularly when I try to take photos indoor in a restaurant without flash for example during a birthday party.
I always have a problem in taking multiple persons in a frame (lets say 3 persons), there is always one person on the right or left who appears to be a bit soft (not sharp) even if I use f6. I cant use higher f number as the shutter speed will be too slow (increase blur) and ISO was already in 1600-2000.

Taking photo of 1 subject or 1 person is not a problem, i can use zone or point AF.

I also need to know what is best seting in taking photos during birthday indoor such as birthday party with low light and no flash. Should I use AI servo or AI focus? One shot is out of the question i think. And should I use evaluative or spot metering for objects?

I know I should have bought a flash but thats another world to learn.
Thank you in advance

FYI, lens I used was combination of 50 mm, 70-200 and 16-35 (for wider capture) Canon 5DIII

sample picture (ok this was f4.5 so that might be the problem, i have another with f 5.6 with same problem)
3G4A9380 by Ivan Sutrisno, on Flickr

- - - Updated - - -

I think i deleted some of them as I was frustrated lol, but here is another better example with f5, iso 3200 (doh) 1/125 speed (cant do lower as these babies are moving alot) the baby girl in navy blue appears to be softer than the girl in red dress.
3G4A9557 by Ivan Sutrisno, on Flickr

***
Edited by ameerat42 to reinstate images below, in the order they originally appeared (but both same size)...
***
3G4A9380 by Ivan Sutrisno, on Flickr

3G4A9557 by Ivan Sutrisno, on Flickr

[ameerat42]

I can't find any Esif info to check your exposure settings for this shot.
Clicking on it takes me to a Yahoo! log-in page Also, I cannot
find it in your Photostream.

So, going on what you have here, and assuming it is not a cropped shot,
I'd say "too close for the aperture used". (Ie, the aperture can't yield an
acceptable DOF.)

So, depending on how well your camera handles high ISO, use a higher one
to allow a smaller aperture AND get a bit farther away from your subjects.
I'd guess that about 3x this apparent distance may have given you
better results.

You'd have to do a bit of trial-and-error, but that's about it.

[ivans75]

Hi, thats because I put these on private sorry I ll make them public now

[ameerat42]

Ta. Well, that's "not too bad" for noise in the higher ISO shot.
Looks like what's left to do is increase the subject distance for
the likes of the first shot.

I would say, though, that for serious "baby shots" you should
really use some reflector-type flash lighting. You will certainly
get lots of "iffy" shots using your method for the 2nd type of shot.

[KeithW]

Problems with photographing groups of people in low light? Try these:

1. Get them to pose on the same plane. Or move yourself so that they are all on the same plane. This means you can get away with less DOF.

2. Longer lenses = less DOF. On the other hand, wider lenses = more distortion for people on the edge of the frame. The lens I typically use in restaurants is either 28mm or 35mm.

3. Stop down as much as possible. I have a strict "no flash" rule in restaurants because I don't want to disturb other diners, which means I have to crank the ISO. Stopping down also means slower shutter speeds, so I brace myself with both elbows on the table, or lean against a column.

4. If you have image stabilization, use it! Or go and buy a lens (or body) with IS if you are going to take these types of photos often.

5. You will be surprised how good a humble phone camera is at taking good shots of groups of people. This is because it has stonking DOF compared to any large format camera you might be carrying. Given that most restaurant photos are happy snaps and you are not trying to create art, you may as well use your phone camera.

6. If all else fails, remember that if you are further away, you get more DOF. Go further away, use a 35mm lens, and crop. Your subjects will fill the tiny center of your frame, and you WILL lose resolution after you crop. But at least they will all be in focus, which is more important.

(edit) --- just re-read your post.

As for your camera settings, I tend to prefer full manual everything, including manual focus. That way I get maximum control of every setting I need and I know the camera isn't going to try to over-ride me.

But if you don't want to do this, you should at least separate exposure metering and AF on your 5D. By default - when you half press the shutter button, it triggers both AF and exposure metering before the shutter fires. For years when I was shooting Canon, I would have these settings:

- half press of shutter button to take exposure ONLY
- AF set to the "*" button at the back
- AF point - center point ONLY. AF = single shot.
- Exposure = evaluative.

The reasoning for this is to give me control of what the camera AF's on. To take a picture, I point the camera at the subject so that the center AF point lands on what I want. I press the "*" button to get focus, then recompose and shoot. Remember, the more control you cede to your camera, the more likely your camera will screw it up.

[swifty]

This is purely an issue of dof.
You need to place your subjects all within the dof of your chosen settings.
Technically you could have many more subjects than your example as long as they are all in a line (depth wise).
Once you have a subject that is clearly in front (the baby in your example) or behind the plane of focus you’d need to rely on increasing your dof from your plane of focus to encompass your subjects in front or behind this plane.
To maximize your dof you need to determine where to focus since your dof includes things a little in front and a bit more behind of your plane of focus. To make things easier many people just place the focus point on the front most subject.

To increase your dof, use a combination of backing away from your subject, stopping down and using a wider focal length. The focus distance (subject to camera) has the greatest impact on dof.

If you know your lens really well you can also utilize its (known) field curvature if it has any. Many lenses don’t have a flat plane of focus but a curved one. If you know how it’s curved you can place your subject within that curvature.
But in general if you can’t move the subject, you move yourself to a position that has the least depth variation relative to your subject. In your example you’d need to move to your left and arc your lens clockwise right such that the man and baby are both roughly equiv-distance to the camera. Then focus on the front most subject (could be your side subjects or the woman.. hard to visualize exactly from the picture).

- - - Updated - - -

In your second example with the two babies, you’d have a hard time for spontaneous movements such as the red baby leaning forward. I can’t see that clearly in this example cos i’m on my phone but if the focus point is on the red baby’s head, the plane of focus is now in front of the blue baby and so blue baby will be a little softer.
But when the red baby lifts her head up, they are essentially on the same plane so focusing on one should result in both being equally sharp.

[ivans75]

Wow great tips!!!

will look into this asap guys.
And yes i should have used my 16-35 lens @ 35 here more often instead of the 50 mm. I must admit i felt bit lazy to change since i do single portait on the birthday girl many times.

i had my wife with her phone covering the rest of the scenes so we were pretty much covered. But just found it frustrating that i got alot of bad shots

printing these tips out now

[ricktas]

I was going to take a look and comment, but the photos have disappeared. If you have removed them, please don't. As others can no longer comment and the answers can help others learn how to improve, not just yourself. But without any photos, this thread is useless now.

[ivans75]

Hi Rick I dont think i removed them. I will check them and get back here asap. Sorry about that

- - - Updated - - -

Hi Rick I dont think i removed them. I will check them and get back here asap. Sorry about that

Just checked on flickr for some reason they go back to private/friends. I just made them public again.

[ameerat42]

That's odd how the images disappeared. I checked the code and it looked OK.

In the original post you can click on the blank image space and open the image in Flickr.
I copied the BB code for each again and re-posted it below the originals. They then appeared.

Did you use the "tree-looking" Insert Image button to link them the first time?

[swifty]

I had a better look on a computer screen.
Re: image 2 with the two babies. Focus plane in on the red baby's face which is roughly the same as her toes as well as blue baby's toes. Blue baby's face is a bit behind this plane, roughly equal to her left hand.
In addition there's a hint of smear on blue baby's face, most likely she actually moved a bit despite looking as though she's quite still.
But to be honest, this one really ain't too bad but I guess it depends on what you intend to do with the photo.

[ivans75]

That's odd how the images disappeared. I checked the code and it looked OK.

In the original post you can click on the blank image space and open the image in Flickr.
I copied the BB code for each again and re-posted it below the originals. They then appeared.

Did you use the "tree-looking" Insert Image button to link them the first time?

hi thanks, it was due to the privacy status. I made them public now

[Geoff Port]

I have been reading this thread with interest attempting to take all the advice in. The quote from you ameerat42 caught my eye.

So, depending on how well your camera handles high ISO,[/QUOTE]

This has been a never ending source of frustration for me. Why is it that others on this forum can take razor sharp images using ISO settings of 800 - 1600 or higher?
When I attempt similar, using a tripod and a remote control my images are grainy and far from sharp.
Obviously a Canon 60D is a far cry from a 5D111 but I thought it, (the 60D) would achieve better results than it does. I have always blamed my inability to master the technology but you have cast doubt on that thought process ameerat42.
Can you give me an explanation as to why some cameras handle high ISOs better than others?

[ameerat42]

I can only [rather non-technically] guess, Geoff: sensor design; sophistication of electronics; processing algorithms (for in-cam jpegs)...
Then, on the PP side: mainly too aggressive manipulation of image data; judicious application of noise-reduction software.

That's about all I can offer, but others will surely add to it.

- - - Updated - - -

PS: Don't forget "noise" in any context means "signal-to-noise ratio".

[swifty]

PS: Don't forget "noise" in any context means "signal-to-noise ratio".

This is a very important point and often forgotten.
An image taken at low ISO can have more noise than a high ISO image in absolute terms but because of the overwhelmingly more signal on the low ISO image, you don't see or notice the noise.
Many high ISO images are 'noisy' largely due to the lack of signal present. When you hit the ultra-high ISO ranges, there are so little signal usually that it's predominantly shot noise.
There's also read noise which is what Am refers to in reference to the technology and sophistication of the electronics and that has to do with how much extra noise the electronics is adding. This is where some of the latest sensors, particularly the Sony Semiconductor derived ones are really good.
Sensor size has to do with how much signal is collected. Ie. the larger the surface area, the greater the collection area. Since we're talking Signal-to-noise and not noise alone, technology also plays a role in how efficient a given sensor collects the signal and is often referred to as the quantum efficiency of the sensor.
So a combination of maximizing the data collected and minimizing the read noise added is how modern sensors betters older ones.
But there are shooting techniques to maximize the SNR of any given sensor eg. ETTR (without blowing highlights).
Geoff: we'd really need to see the images you refer to, to give any advice on why they might appear to be too noisy since the 60D is really no slouch.

[Geoff Port]

Thanks for the explanation swifty. I'll pull a couple of images out and post them for your perusal.

[arthurking83]

....
This has been a never ending source of frustration for me. Why is it that others on this forum can take razor sharp images using ISO settings of 800 - 1600 or higher?
......

I suspect that you're probably being a little too hard on your self and your images!

there is a very high probability that you're not comparing the images quality under the same set of conditions.

1. if you're seeing razor sharp images that other's have captured at high ISO, then almost certainly you're seeing them at 1000, 1200, or so pixel width resolutions .. ie. downsampled from their original image size.

2. you'd be viewing your images at much larger degrees of magnification, which is a natural tendency to do. And you're probably not using much, or any noise reduction application, or maybe not as heavy handed with it or something.

Like swifty said, we'd have to see some of your images, and under what conditions you've captured them too, what processing you've done to the images .. etc, etc.


ps. just had to go back to some very old reviews to compare the 60D and 5DMkIII, and in reality they're aren't too far apart in terms of high ISO noise quality.
probably 1 stop difference. (ie. 5DIII @ ISO6400 = 60D @ISO3200) ... and ISO3200 on the 60D should be very usable with the right processing and resizing.