Focus Point Positions!!! Why not one at the thirds!

captures.in.time

captures.in.time

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Whilst standing waiting for light this weekend... and focusing a landscape shot something occured to me... why is there not a focus point on Canon cameras at the rule of thirds points... that would be really usefull as when composing landscapes it would make focusing a little easier... especially for foreground objects in the bottom right or left... the focus points towards these areas are still a bit away and and I often find myself focusing using auto focus and then sticking the camera onto manual focus before recomposing the shot... especially if im taking a few of the same at dif settings with the same composition!
 
The AF lock only locks the focus for about 20secs I think on my camera... no doubt there will prob be some custom function button I could change... but if im going to be there focused for ten mins waiting on light... maybe changing filters etc... I prefer just to flick the switch to manual focus so all im doing is focusing once and then eliminating focusing completely for that shot... I just find recomposing all the time on the tripod tricky.

M
 
markelliot said:
but if im going to be there focused for ten mins waiting on light...
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... then what you want to do is focus, recompose, wait for the light, and shoot. Where's the problem?
 
The focus point is so different for different types of shot. Landscape, portrait, macro. Did you know that in macro there is no thirds, its halves.
 
StewartR said:
Oh wait, I get it. I bet you're using the shutter button to focus, aren't you?
No doubt there will be. ;)
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Yes I use the shutter button to focus... I know you can somehow change this but not had time to experiment with this! I take it it's the thing to be doing....???
 
StewartR said:
... then what you want to do is focus, recompose, wait for the light, and shoot. Where's the problem?
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Focusing then recomposing isn't really an accurate way of doing things tbh. Granted on things like landscapes it won't do much damage but on closer subjects it can cause you to miss focus.

Focus points are never right where you want them, but I'd agree that points on the intersecting thirds would be handy.
 
classcams said:
The focus point is so different for different types of shot. Landscape, portrait, macro. Did you know that in macro there is no thirds, its halves.
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What does that mean?

Compose how you want to make the image you want. Ignore all these rules of thirds, rules of halves etc.

Walk away now before you're brainwashed!
 
now i am 100% sure i asked this before and got some technically answers but i cant for the life of me find the thread. All i can remember is that the centre focus point id the best one to use.

also if you have the time and your on a tirpod why not manual focus?
 
Toothie^^ My eyesight is fairly poor... I wear glasses and tend to think the autofocus will prob do a better job of making sure objects are in focus than I can!

I struggle seeing subtle changes in the viewfinder... I have bought the canon eyepiece extender which makes it all a bit smaller which has been a fab purchase.... but I still struggle with it a bit... I can never see that much of a difference when I rotate my polariser either!

Mark
 
for landscape, dont you set it based on the hyperfocal thingy, and virtually everything is sharp or am i missing the point:thinking:
 
The central focus point on my 450D is a cross point sensor and is more accurate than the others when partnered with a lens f/2.8 or faster.

However, some of the focus points on the 450D fall as near as dammit on the rule of thirds intersection:

Canon_XSi_AF.jpg


There's four points which are near enough in my book so you could select those if you don't wish to lock focus and recompose but I guess it depends on your camera offering these same focus points.
 
NorthernNikon said:
My thinkg as well. Focus a 20mm lens at 2m and f:8 and just about everything in your shot will be in focus
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Glad it wasnt me losing the plot again:D
 
Try using back button focus. Then once set, the shutter only takes the picture, rather then focus and take the picture. Or, once focused, switch to manual, so the focus wont change.
 
Deckard said:
The central focus point on my 450D is a cross point sensor and is more accurate than the others when partnered with a lens f/2.8 or faster.

However, some of the focus points on the 450D fall as near as dammit on the rule of thirds intersection:

Canon_XSi_AF.jpg


There's four points which are near enough in my book so you could select those if you don't wish to lock focus and recompose but I guess it depends on your camera offering these same focus points.
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Those are the ones I tend to use... however on the 5d they are a bit further centralised than you have shown in the screen shot there... not much but enough to mean a bit of recomposition... I tend to like landscapes with an object right in the bottom third too so sometimes you want to focus on the front of that object... It was really just a thought I had... didn't think i'd generate so much discussion... though I def need to look at my custom functions again and focus buttons being diff from my metering function... that sounds usefull!

M
 
classcams said:
The focus point is so different for different types of shot. Landscape, portrait, macro. Did you know that in macro there is no thirds, its halves.
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I think this needs an explanation. What the contributor is reffering to is depth of field.

When you focus on a point there is a certain area nearer to and further from the camera that are still in acceptable focus. This in-focus zone is what is known as depth of field.

The in-focus zone has 1/3 of its area closer to the camers than the point of focus and 2/3 of it further away than the point of focus. The size of this zone increases as you stop down you lens.

That is why traditional landscape photos are taken at a high f-number and it is recommended that you focus a 1/3 of the way into the scene. Thay way, at a certain stop you will have everything in focus.

When you are talking about macro photography, this in-focus zone is split half and half closer to and further from the point of focus.

Also, wide lenses have a bigger depth of field. When you go ultra wide it is pretty much full focus throughout when you stop down.
 
subseasniper said:
I think this needs an explanation. What the contributor is reffering to is depth of field.

When you focus on a point there is a certain area nearer to and further from the camera that are still in acceptable focus. This in-focus zone is what is known as depth of field.

The in-focus zone has 1/3 of its area closer to the camers than the point of focus and 2/3 of it further away than the point of focus. The size of this zone increases as you stop down you lens.

That is why traditional landscape photos are taken at a high f-number and it is recommended that you focus a 1/3 of the way into the scene. Thay way, at a certain stop you will have everything in focus.

When you are talking about macro photography, this in-focus zone is split half and half closer to and further from the point of focus.

Also, wide lenses have a bigger depth of field. When you go ultra wide it is pretty much full focus throughout when you stop down.
Click to expand...

Yeh since this post and another I have learned allot about hyperfocal focusing... I did know about it... but never really if you know what I mean... now I do and I think focusing for landscape is allot simpler than I was making it... and I should get better results... or certainly less hassle free landscape focusing!
 
Hyperfocal focussing is best used when you realise that it won't get everything in focus. More realistically it will get everything nearly in focus to a reasonable degree, for a certain sized print.

If you use the hyperfocal chart printed on most lenses, on 35mm film, you get what the manufacturer deems acceptable focus at a reasonable print size viewed a reasonable distance away.

If you're the sort of person who likes to make 18" prints and get close to look at them, you may be disappointed.

It's all about compromises!
 
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