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minnum
01-05-2008, 2:05pm
I could use some advice on focusing methods. This is still all so new to me, but I'm SO keen to improve.
Anyway, I have setting on Auto focus... I lock the AF point over one eye then re-compose my shot and press the shutter.

Is there another, better way? especially when it comes to getting both eyes in focus?

I know how to change AF points in my camera, but I can only figure out how to change the one AF point (from middle, to side, up and down) ... What if I want to add AF points, so that more little red dots are showing and I can hold them over both eyes then lock the focus! Sorry, I know this is 'novice-talk' to you guys!
I find this frustrating too with group shots as I only ever have the one AF point in the middle.... with group shots, shouldn't they all be there. Am I missing something? Is there some crucial setting I haven't found? lol :p :o :D

Or do I just need a smaller aperture (bigger number)? to get more DOF. It is when the subject's head is slightly turned and one eye is closer to me that it happens, so is it just a matter of having a higher number? In whach case what f number would you suggest?

p.s.
I have attached a photo so you can se what happens to the eye furthest away. The aperture on this was f4 and ss 1/160

Thanks for your help :action66:

rbudiardjo
01-05-2008, 2:21pm
it also happens with my 400D if i use the selective AF. how about increasing the f stop (just a bit)? i suppose if you want to make the left eye focus as well, the area where the eye is will be in focus as well. the other way is to use PP, but it may come out awkward.

sorry can't help with your question...

Outback Flyer
01-05-2008, 2:21pm
Hi Minnum,
Yoy got it yourself with the DOF comment,
The red dots / squares only indicate the possible positions of focus, ones that may pick up and lock depending on your focus mode selected.
But a further tip, when shooting with long lenses, you need to allow for the compression of view, ie a shot @F4 through 200mm will not render any where near the DOF that a shot using say your 35mm lens @F4 , so I think you used F4 for the portrate shown, the DOF looks like it was only mabe 10mm, or less, so with the subject's face at the angle like that the depth from one eye to the other was mabe 25mm or so.
Dont be afraid to step the lense down to F8 or even F11 , with the long lense you will still achieve the split from the background as desired, but will in that example achieve both a catchlight and sharp focus on both eyes.
Hope that makes sense.
Cheers, John.

ving
01-05-2008, 2:21pm
yup you got it... smaller aperture = more DoF.

alternatively...
you seem to have enough Dof for both eyes. if you had focused inbetween the eyes they both would have been in focus.

The_Scroop
01-05-2008, 2:25pm
What you are doing is fairly standard, focus, lock, recompose.
I assume you are using the setting that has single focus point turned on. What camera are you using?
There is a setting on all dslr's that allows you to change the focusing from a single point, to a series of points, and even a setting to utilize all focusing points.
You can't choose two separate points but if you use the setting which uses multiple points, you are bound to have a couple of points over the eyes to ensure they are in focus.

When it comes to group photo's, you best method (in my opinion) is to select the setting that uses multiple points, and then set your aperture around f/5.6 or higher.
This should allow for most peoples faces to be in focus.

The amount you have zoomed in will also have a large effect. 200mm @ f/2.8 will have a much smaller DOF compared to 50mm f/2.8. So if you were taking a group picture, its better to use a shorter zoom and stand closer, rather than a longer length and standing back.

Of course these are my opinions and there are other methods out there.

minnum
01-05-2008, 3:05pm
Hi guys,
Thanks so much for your replies :)
I used 50mm f1.8 for this photo (and for all my portraits). The only other lens I have is the 18-55mm standard kit lens... and I don't really use that.

I haven't been able to find the setting on my camera where I can choose multiple AF points. That's exactly what I'm after. I must look through my manual again.

(My camera is Canon 300D)

Also, I didn't know about focusing between the eyes would get both eyes in focus. Maybe that's where I'm going wrong too. I always focus on one eye, then lock.

Thanks again.

If anyone knows the Canon 300D and has an idea where the multiple AF point setting is, then please let me know. I will of couse look in my manual again, but I just read about it the other day (even made notes on it) and didn't come across it.

I did think it was strange that it didn't have that setting... now that I know it's there, I am more encouraged to figure it out :D

ricktas
01-05-2008, 3:27pm
I would add to this.

If you are going to use an aperture of f2.8 - f4 I would suggest use don't use the focus, hold shutter and recompose method, as you generally do not move naturally on a single plane, therefore when you recompose, you could also move slightly closer or further away from your subject and this can exacerbate the OOF effect.

kiwi
01-05-2008, 3:35pm
Re the point of focus, a master of 50 1.4 portraits done at 1.4 told me to focus on the bridge of the nose, seems to work.

MrJorge
01-05-2008, 3:55pm
If anyone knows the Canon 300D and has an idea where the multiple AF point setting is, then please let me know.

On my 400D there is a button that has a rectangle drawn on it with a mini version of the AF points inside. Hitting this button lets you cycle between all AF points on or single AF point mode.

Did a quick google search and found this for you...

http://photonotes.org/manuals/eos-rebel-2000/#focuspoints

And having a flick through your camera manual here

http://support-au.canon.com.au/contents/AU/EN/0900027401.html

Page 62 has the bit you want in the resulting PDF.

Looks like you hit the button that is a rectangle with a dotted cross on it (looks like top right corner) button. Then you scroll the dial while looking in the viewfinder to select which AF point is in use. Then when you have what you want selected you half press the shutter.

Presumably when you scroll through with the dial it will eventually go back to having all AF points selected.

ving
01-05-2008, 4:06pm
glad to help. :)

see your problem was that the person is not facing straight on. so when kyou focused on teh closest eye it didnt really make any difference where you move in a sideway motion because teh closest eye was still going to be the main focus. if kyou had moved forward at the same time things may have worked better. the place where the camera AFs to is the center of the focal area and the DoF extendes backwards and forwards of that point. hence focusing 1/2way between the eyes :)

make sense?

minnum
01-05-2008, 4:19pm
Thanks so much. You're a star :) I will look at it all tonight and let you know how I get on :D

minnum
01-05-2008, 10:12pm
If you are going to use an aperture of f2.8 - f4 I would suggest use don't use the focus, hold shutter and recompose method, as you generally do not move naturally on a single plane, therefore when you recompose, you could also move slightly closer or further away from your subject and this can exacerbate the OOF effect.

Ricktas, so if I don't use that method what do I do?
Do I have all AF points on and compose my photo, then shoot, even with portraits?
Or? What if I focus between the eyes, like mentioned, then I only need to recompose slightly after locking focus.

Thanks for all your help.
I found the setting for all AF points. Like suggested, I just had to keep scrolling. yay :)

arthurking83
02-05-2008, 6:46am
focus and recompose method as Rick suggested is what caused the slightly OOF right eye, I don't think it was a lack of DOF.
As Risk said, when you recomposed, you altered the plane of focus(in this case most likely moved backwards a little bit).
I do it all the time if I use the focus-recompose method, so I sipmly stopped using that method, and now I'll just move the AF-point in the finder.
Also! Don't be afraid to refocus manually!!
My main reason for purchasing a manual focus lens over a AF version.
Nikons 50mm f/1.4 is not AF-S, which means you can't fine tune the focus with a simple twist(very annoying). The focus is mechanically linked and makes it hard to manually adjust on the fly.
If the viewfinder is clear and bright and affords you the ability to easily fine tune focus, manually, then do so.

minnum
02-05-2008, 8:03am
Thanks so much for your feedback. It's just that I'm photographing children and the little ones just don't stay still long enough for me to move AF points in the finder or fine-tune focusing manually. I've got to be so quick. Will give it a go with my daughter though and see what happens.

Thanks again :action66: