View Full Version : Entire frame in focus
arnica
24-01-2012, 11:55am
Hi All,
I've been wanting to ask this question for ages, but haven't gotten around to it until now. I mainly take landscape photos some which include people in it every now and then.
However when I take the picture, I can never seem to get the entire frame in focus (with detail). I have a basic understanding of depth of field and you can control this by adjusting the aperture (f/value), and focusing to infinity (sideways 8).
When ever I take pictures, it seems that the majority of the frame in in focus (around 90%) and the remaining (usually around the edges) seems to be out of focus (not in detail). Also, what metering mode should I use (or is that for auto focus only)?
I'll post up a few pictures later tonight and show you what I've done in the past. Could you show me of point me in the right direction on how I can have the entire frame in focus?
junqbox
24-01-2012, 12:04pm
What will help first off here is usung the shorter of your focal lengths, eg- 24mm not 75mm. Also, using a smaller aperture, eg- f11 not f1.8 (which will require a longer shutter speed).
It may be worthwhile taking your lens(es) out somewhere and running a few permutations so you get a handle on the different outcomes from different settings.
There's more, but this will get you towards a solution once you experiment with your gear.
arnica
24-01-2012, 12:16pm
What will help first off here is usung the shorter of your focal lengths, eg- 24mm not 75mm. Also, using a smaller aperture, eg- f11 not f1.8 (which will require a longer shutter speed).
It may be worthwhile taking your lens(es) out somewhere and running a few permutations so you get a handle on the different outcomes from different settings.
There's more, but this will get you towards a solution once you experiment with your gear.
Thanks for your reply jungbox, I'll give that a try.
Tom J McDonald
24-01-2012, 12:19pm
You may have a dog of a lens if it's always soft around the edges.
arnica
24-01-2012, 12:26pm
You may have a dog of a lens if it's always soft around the edges.
I could have, but I reckon it's more the setting(s) that I shoot at.
Tom J McDonald
24-01-2012, 12:55pm
Ok... Stop down as much as practicable. I aim for f/11 as being the safest aperture for full frame for me.
What lens are you using?
Ok... Stop down as much as practicable. I aim for f/11 as being the safest aperture for full frame for me.
What lens are you using?
I mainly use the 24-70mm
Tom J McDonald
24-01-2012, 1:13pm
Ok. Small apertures are the way to go.
Ok. Small apertures are the way to go.
Thanks for your help Tom. I'll post up some of my experiments.
photomike666
24-01-2012, 2:19pm
There's also a trick called the hyper focal point. At any aperture the depth of field is two thirds in front & one third behind the focal point.
If u use a tripod and stop down around f16 (really slow shutter speed, hence the tripod) and focus two thirds through the landscape everything comes into focus.
photomike666
24-01-2012, 2:22pm
Also using this method, if u cannot get everything into focus, you can move the focal point to choose which part of the image is not sharp. Having a depth of field preview is handy here
ameerat42
24-01-2012, 3:05pm
And now we've all finished guessing why, post a picture to illustrate what you originally meant.
Depth of field is a tricky one I suffered the same problem when I started off taking landscape pictures as mentioned above f11 will give you good depth of field on a full frame having said that cameras with small sensor sizes will give you better depth of field with larger apertures like f9 I know for a fact as I have both full frame and a crop sensor camera. But it is just not enough if you set a small aperture value when you auto focus you need to focus one third into the scene this is close to the hyperfocal point as mentioned above. Another point to remember is how close the foreground subject is for example I use a 17-40 lens on a full frame to take a landscape shot at 17mm so my foreground subject should not be closer than 1.42 meters for a aperture value of f11. You can refer to the hyperfocal chart online.
ricktas
24-01-2012, 5:55pm
also do not focus at the hills way off in the distance, or the log in the foreground. Focus around 2/3 of the way into your scene. There is a thing called the hyperfocal distance (http://www.dofmaster.com/hyperfocal.html).
William
24-01-2012, 5:59pm
Yep on a crop sensor (30D) , Using my Sigma 10-20, f8-f10 and focus 1/2 thirds into the scene (In this shot I focused halfway up the track) will give sharp definition from front to back , EG this one I posted today
f8 @12mm
There's also a trick called the hyper focal point. At any aperture the depth of field is two thirds in front & one third behind the focal point.
If u use a tripod and stop down around f16 (really slow shutter speed, hence the tripod) and focus two thirds through the landscape everything comes into focus.
When u say focus 2/3 into the frame, is it from the top of the bottom?
Still at work ... long day today.
ricktas
24-01-2012, 6:12pm
When u say focus 2/3 into the frame, is it from the top of the bottom?
Still at work ... long day today.
2/3rd of the way INTO the scene. So say you have person in foreground, river behind them, plains behind that, and distant hills, Use a small aperture and focus on the plain or the opposite river bank. The idea is that for a certain distance closer to, and further away from the focal point will be in focus. If you focus on the hills, then anything really close will be out of focus. If you focus on the person, the distant hills will be out of focus. So focus somewhere in between.
William
24-01-2012, 6:46pm
:) Thanks Rick , I could'nt explain it properly , Hence the halfway up the track :D
ameerat42
24-01-2012, 7:19pm
The "into" part usually means "from the observer/photographer".
William
24-01-2012, 8:10pm
I may have to add , That a wide angle lens like the 10-20 Sigma or 10-22 Canon have an inherent built in big DOF by design , You basically cant go wrong to get the whole image in focus , But the same focus rules will apply to any lens
Google, " On-line Depth of Field Table " it will give you depth of field of all lenses,and cameras, as the circle of confusion is different for most camera models you wont be able to use a rule of thumb to get accurate focus where you want it.
The rule of thumb is to get focus at 2/3 into scene, that will give you 1/3 of the scene focused in front of focus point and 2/3 behind.
Jack.
PS it is getting late hope you can understand this.
Good question and one that, also being new to photography, I wish that I had asked. I tend not to do things by halves and so wanting a greater depth of field on my most recent photo shoot I ran around taking photos of everything at f22. The results were not as clear as I expected so I did some more reading and discovered information about diffraction which is probably the reason for my disappointing results.
Next time I will follow the suggestions that the more experienced and wiser heads have provided in this thread and try around f11 and check the results. I have also now got an app on my phone to help me with figuring out the hyperfocal distance but over time I want to learn to figure this out and set my camera appropriately without this aid.
Thanks again for asking the question.
ameerat42
27-01-2012, 1:10pm
...I ran around taking photos of everything at f22. The results were not as clear as I expected so I did some more reading and discovered information about diffraction which is probably the reason for my disappointing results...
The other 1/2 to this is that the amount of diffraction you get (at f/22 say) depends on the focal length of the lens. A shorter focal length will have a smaller aperture, and hence greater diffraction effect, than a longer focal length at the same focal ratio (f-stop).
I read an article in from a magazine recently and it talked about "Hyperfocal focusing". It said an easy solution is to use manual focus, compose the shot and focus on hyperfocal distance by eye.
Can someone explain what that means to me? I've included a photo of a table on hyperfocal distances.
http://farm8.staticflickr.com/7197/6914874861_4bdf6935c9.jpg
Correct me if I'm wrong, but if I refer to the above table. /
If I am shooting at f/11 @ 28mm, does it mean in order for me to have he entire frame in focus, I will have to focus on an object 7.8ft in front of me?
It really annoys me that modern lenses have dropped the DOF scale. With my old film camera I would focus on the foreground I wanted and then manually Move the focus ring to put this point at the front (or back) of the DOF range indicated on the lens. In a landscape I would try to get the DOF to reach back to infinity. There are some apps for Android (and I assume iPhone) that calculate the DOF range for you at a given aperture that tells you where to focus at.
Here is a link to explain the old school gibberish I speak of
http://www.fineart-photography.com/dofScale.html
ricktas
22-02-2012, 5:28am
Correct me if I'm wrong, but if I refer to the above table. /
If I am shooting at f/11 @ 28mm, does it mean in order for me to have he entire frame in focus, I will have to focus on an object 7.8ft in front of me?
Yes! Note how the distance changes depending on the lens length and aperture. It is all inter-linked just like Aperture/ISO/Shutter Speed.
And now we've all finished guessing why, post a picture to illustrate what you originally meant.
I finally got around to finding a picture to illustrate what I meant in OP.
http://farm8.staticflickr.com/7048/6773852658_2ffa1e0138.jpg
That's going to be pretty tough to get from 0 to infinity! I wonder if there was a different angle that would move the log further back into the scene?
Maybe the focus point could just bring the log in focus and let the trees blur a bit?
Sometimes you hit limits that means your idea does not work out but often there are alternatives.
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