Focusing

MarcusF

MarcusF

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Name
Marcus
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Yes
...its doing my head in!

Right, at the minute I'm getting fairly pants shots when not using automatic mode. Regardless of subject or location. But on automatic mode it won't let me change which focus 'point' I want to use. Or anything else for that matter!

I've been trying to take some nice (by my standards!) portrait style pics of my dogs. When I auto focus on them and take the pic the nose and muzzle is in focus but the eyes aren't. Once I get the beep if I try to move the camera slightly to get the eyes in focus I end up with everything out of focus :bang:

Am I making sense?

My nifty fifty arrived today and I've been trying some shots this evening. Unless I'm nine miles away I can't get the eyes in focus without chopping off the nose.

And the flash makes their eyes look horrible :(

Some pointers would be awesome and much appreciated.

IMG_0577.jpg


I've resized this pic slightly but haven't cropped it or done anything else. And this is the best one I took :shrug:
 
It sounds like your aperture is causing this. If you're using something like F1.8 then you basically have something like an inch or less in acceptable focus (depends on how far away you are from the subject). When shooting dogs the fact they have a large snout can make it harder to use the lower apertures.

If you bump it up to something like f4 or a bit higher it will increase your depth of field. This will make it easier to get both the nose and eyes in focus. Also, as Lee said, always try to get the eyes mainly in focus too because that's what people will be drawn to in the photo first.
 
Right, at the minute I'm getting fairly pants shots when not using automatic mode. Regardless of subject or location. But on automatic mode it won't let me change which focus 'point' I want to use. Or anything else for that matter!
Click to expand...

it would make sense that another 450D owner might need to explain why you can't move the focus point around, as I am assuming the camera does have more then one, so something in your settings is amiss I think. Even with just one though, focus on eyes rather than nose, as already mentioned, eyes are what pull the viewer in, then when it beeps, move it to fit nose in. Remember though, if aperture is wide open, even just moving the camer aenough to fit nose on will probably throw if off the prefocused plane enough that it will still be blur.
It almost wouldnt matter if the nose was OOF, but increasing aperture number [decreasing size of the 'hole'] will improve the amount of image that is in focus.
 
In AUTOMATIC mode the CAMERA makes all selections for you and uses ALL the focus points. You need to move out of Auto and try P (program) mode. That is basically Auto but allows you to change the camera settings - one being the focus point.

Not sure what the buttons are but I'd suggest you rtfm first :)

Shooting a dog like that with the 50mm f1.8 isn't simple. To get the dog's head wholly in focus you may need to be up at around f8 or even f11!!! So you are not going to be able to do it. At f1.8 depth of field is very narrow.

If you's shooting 6' say from the dog at f1.8, the depth of acceptable focus is only about 3.5"! The dogs nose to eyes is probably close to 8" or maybe more so you need to be shooting from 6' at around f8. That will give you a sharp head to nose. Shutter speeds are likely to be VERY slow at that especially indoors unless you use flash as the main light. In that case switch the camera to M. Set the camera to f8 and your shutter speed to 1/60th. Increase your ISO to about 800 (helps the flash) and the flash will expose the subject properly. Before you shoot, make sure your single focus point on the camera is set to target the near eye of the dog .

Fire

You could step back a little more too which will help increase the dof.
 
Basically in automatic mode it won't let you move focus points, or do anything else really. But it will in other modes like AV for example. Same with apperture. But if I stick it in AV the pics come out worse....lol

I get the part about getting the eyes in focus first. Getting the eyes in focus was my aim, but it didn't work out as planned...lol. I'll give that a shot. Its just everytime I aimed for the eyes, then moved the camera, everything was out of focus. But then if the apperture being low gives me a short DOF (or whichever way round it is), then that might explain that.

I want to be able to use one of the AV type modes but everytime I do the pics come out pants. And because I'm very new to this, I don't know which setting to change.
 
MarcusF said:
Unless I'm nine miles away I can't get the eyes in focus without chopping off the nose.

And the flash makes their eyes look horrible :(
Click to expand...

To answer these points.

You can't - no matter the camera! And you will NEED flash to light the subject. What will help is an off camera flash to add some modeling and a soft diffuse light source.

Either that or do it during the day in window light. Try starting at f8 (f1.8 is just too wide open for a dog with a nose that length) see above!
Cheers
JD
 
Thanks EOS. I'd posted before I saw your post. I'll give all that a shot tomorrow, excuse the pun. Yeah their nose to eye distance is about 6" so that will explain a lot. I understand what you guys are saying so thanks for that, and the patience!
Its hard because I don't know what to expect or what is or isnt possible yet. So I'm trying to apply what I've learnt so far. Just badly :lol:
My other dog is easier to photograph as he'll sit still and you can pose him. Problem is he's black so that makes things a real challenge.

I don't intend to be beaten by a few pieces of glass and a bit of plastic :D

Ki User - Do they do a version of that calculator for the layman?...lol. I've barely scratched the surface of DOF but I've bookmarked it for later.

Thanks everyone. If you guys think of anything else keep em coming!
 
I got a nifty fifty a while ago and found the same problem

It's definetley DOF. If you have it wide open then you have a very narrow margin of error, as previous replies, only a small part of the subject will be sharp

I'd strongly suggest moving into manual mode. Keep opening your apperture up until you get everything in focus (have your flash on as you'll loose light doing this) and then when you're happy with the setting and you'd rather not use flash, then turn it off and crank up your ISO until the exposure is right.

You might be better off doing this outside during the day to overcome the light issue
 
Another little trick I've used with on camera flash is to get a little make up mirror and angle it under the flash so the flash is then directed up at the ceiling - easy way to "bounce" it at no cost (I knicked the wifes from her bag)

YOU MIGHT WANT TO CLOSE YOUR EYES WHEN YOU PULL THE TRIGGER AS SOME FLASH WILL BOUNCE BACK INTO YOUR EYES
 
MarcusF said:
. But if I stick it in AV the pics come out worse....lol
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Depends what settings are. In Av, the camera flash acts as a fill light. What's likely to happen is your shutter speed will be very slow soi you need to increase the ISO but even at ISO1600 and f8 your SS will be terribly slow - around 1/8th - you should be aiming for 1/50th minimum.

MarcusF said:
Its just everytime I aimed for the eyes, then moved the camera, everything was out of focus.
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With such a large aperture like f1.8, you need to use the focus point that is fixed on the eye - don't recompose! You'll just throw the eyes out of focus because the dof is so narrow. Imagine a bit of string on the camera. The focal plane is a curve. The camera needs to maintain that exact distance (within a few mm)

MarcusF said:
I want to be able to use one of the AV type modes but everytime I do the pics come out pants.
Click to expand...
You'll learn as you go along what to use and when. For this, I'd use M, ISO800 (maybe 1600), 1/60th and let the flash do its thing.

MarcusF said:
And because I'm very new to this, I don't know which setting to change.
Click to expand...

As I say read the manual - there's tips in there. Look at Understanding Exposure by Bryan Petersen too - Makes it a little easier to get a grip.
 
Ha ha..the wife has one of those too, so I'll try that as well. Do those flash diffusers work at all? The ones that fix over the flash itself.

Going to give these suggestions a try tomorrow. I was going to ask about setting apperture and shutter speed in manual mode but I picked the camera up and worked out how to set them both seperatly.

I also understand now that the lower the apperture the smaller the DOF. Is that right? So if you want a larger area to be in focus, your raise the apperture number?

Edit:

Cheers EOS. That book arrived today actually. Along with the 450D manual for dummies!...lol
 
On the 450D you can change the auto-focus in everything but Auto.

In AUTO the focus will also be set on auto with all the points active and the camera will automatically select the NEAREST point in focus - in the pic this is the dog's nose.

This may also be why you appear to have very small DOF - the camera has focussed on the end of the snout.

In fact in the pic the focus appears to extend at least half way up the snout if not more.

Not a DOF problem just the wrong focus points.

Try resetting to M or AV.

Now look at the back of the camera on the top right hand side.

There are 2 buttons close together.

Press the one marked + and the LCD screen will show the auto focussing points as small oblongs.

Use the 4 keys in the middle of the back - the ones around the SET button.

These will allow you to change the focus points.

Select a point which will allow you to focus on the eyes without moving the camera.

I would suggest trying the rim of the eye as the auto focus will find it easier to get correct focus there.

I wouldn't worry about diffusing the flash - get the focus right first then think about how to improve the shot.

The "Nifty Fifty" is a crackingly sharp lens but only if correctly focussed - like all lenses.
 
Thanks Peter. I've messed about with the focus points before, buy my non auto shots were never as good as when in auto, and as you've said, it won't let you change the points.

It was always a trade off....lol

I've learned loads tonight already so I'll put it into practice tomorrow and keep you all posted.

Thank you :thumbs:
 
P mode is auto :)
 
Once again thanks for your help folks. I took some more pictures this evening when I got in from work and they're a bit better.

Still plenty to learn but even I can see an improvement over last nights efforts.

Talonportrait1-8410.jpg


Rogueportrait2-8410.jpg


:D
 
Certainly better. Now you lust need to master lighting and you can teach the rest of us :)
 
ki_user said:
Much better, what problems are you having with the DOF calculator?
Click to expand...

lol...it might as well be in swahili :gag:

'Circle of confusion', 'Hyperfocal distance' etc. Do they make this stuff up?

;)
 
just need more DOF to get eyes and nose in focus. with large apertures you are better shooting the head from the side that way you get the plane of the face in focus
 
The hyperfocal distance is the point of focus where everything from half that distance to infinity falls within the depth of field.

Circle of confusion still confuses me, excuse the pun.

I wouldn't worry about these so much about these though.

The important ones are DOf measurements.
 
Hi Marcus,

I like the first picture you posted the most !

Is your dog smiling or is that a reflection on his/her bottom lip ? Simon
 
Simon-Australia said:
Hi Marcus,

I like the first picture you posted the most !

Is your dog smiling or is that a reflection on his/her bottom lip ? Simon
Click to expand...

Cheers. It'll be his bottom lip. He won't pose for the camera unlike Rogue so getting a decent shot is harder. But although Rogue will pose, he's black and that makes things more difficult.
 
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