Aperture Priority and Landscaping

DavidUK

DavidUK

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Got a few spare moments so I thought I'd raise the question of aperture priority and F stops.

When I shoot landscapes I use almost exclusively aperture priority mode, and after doing a bit of reading on the forums use either F11 or F22.

My girlfriend got a second hand D70 for her birthday (nice generous boyfriend I say :lol:) and until she is used to it has been shooting in Auto.

Shes come up with some nice shots, and varying apertures where I would normally have used either 11 or 22.

Is there any general rules of thumb as to which F stop to use?
 
This one sparked a long argument a few weeks back m8 !!!

It all depends on the focal length, and how much DoF you want

On your super wide 10-20 f8 focussed practically anywhere from just a few feet away and all will be sharply in focus

The argument went on to discuss image quality, as on some lenses f22 makes for a less shape image than f8 - so where f8 gives enough DoF for you, there's no point using f16 or higher as it won't add anything and may make the image worse

DD
 
This post really interests me...

I do allot of landscape photography and my rule of thumb has simply to go for the highest apature number that I can comfortably hand hold to avoid camera shake when not using a tripod... not using a tripod out of lazyness is probably my biggest flaw in photography... but it often comes due to time constraints... or im nipping out the car whilst on a drive with my pretty considerate fiancee! Obviously if im going for a low DOF effect I go for a smaller apature... but generally I will focus on my foreground interest item... and set the highest apature number I can hand hold at....

I thought this was good practice... but it seems this may not be... can anyone help me out... with my lenses the sigma 15 - 30, canon 28 - 135IS and 75 - 300IS am I actually better going for f numbers like 8 or 11?
 
For me it depends on the landscape. Is there close foreground interest? If so then you will need the extra DOF. If not, then pop on to a lens review site and find the f stop your lens is sharpest at and use that. I would never use more DOF than is needed because small apertures give softer pictures - it is unavoidable.
 
My point was specifically aimed at the super-wide lenses most of us enjoy these days

Have a play with such as this DoF calculator to see what I mean http://www.dofmaster.com/dofjs.html

But if you're shooting a landscape on a 12mm lens and the aperture is f8 - the nearest point that will be sharp (focussed 10ft away) is just 30 inches away, and everything to infinity would then still be in focus

Using the same lens focussed 10 ft away but at f22 would make everything in focus from 12 inches away - so it only makes 18 inches difference!!!

So unless you're laid on the floor wanting those pebbles closest to you in focus as well as the hills 3 miles away, either f8 or f22 will do the job perfectly well

The next issue then is which will actually be sharpest? And on most lenses around f8 is always sharper than f22. So if f8 gives you the DoF you need, it makes more sense to use f8 than f22

Added to which, f8 will also give you a much faster shutter speed, which means you can get away without a tripod more often too and still get totally sharp great DoF shots

HTH :shrug:

DD
 
DonnaM said:
For me it depends on the landscape. Is there close foreground interest? If so then you will need the extra DOF. If not, then pop on to a lens review site and find the f stop your lens is sharpest at and use that. I would never use more DOF than is needed because small apertures give softer pictures - it is unavoidable.
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This is a great post, which has taught me something new today.

When I first got my DSLR camera I spent time trying to get to grips with the full funtionality of the camera and basically just through myself into full manual mode. With more experience I now shoot almost all the time in aperture priority mode to give myself DOF control over shutter speed. I do exactly the same as markelliot, when I am shooting something like a landscape, I increase the aperture F Stop until the shutter speed is getting to the limits of normal hand held limits. I have heard that most lenses do have 'sweet spots', but have always just thought that the higher the F stop the more the DOF is in focus and tac sharp. Therefore in taking a good landscape shot you were ultimately trying to find the perfect compromise between shutter speed and aperture F stop. Are you saying that when using a tripod you can go too far with the f stop to the point of producing poorer images?
 
Yes - The Bulb

Because being Sharp is NOT the same as being in-focus

Depth of Field (DoF) is simply how much of the scene is in focus, how sharp it is depends on a number of factors (i.e. camera shake, subject blur) and what we're discussing here is the quality of the lens

Assuming everything you need is in focus at f8, so the DoF you need is fine and the subject won't be blurred due to your or the subject's movement, then on most lenses f8 will give a sharper image than f22

It really depends on the lens' IQ, but all manufacturers post their resolution power in graphical form, where the lens gets better from wide open to around f8, f11 and steadily worse again thereafter

Of course there are times when you really need f22 or even f32 for max DoF, but where you don't need such small apertures using f8/f11 is almost always better - assuming they give sufficient DoF - and for 2 reasons...

1) IQ is usually better
2) it automatically gives you a higher shutter speed, so again sharpness may be improved by the reduction of the possibility of camera shake or subject movement

DD
 
By stopping down the lens beyond a certain point, detraction occurs with the actual diaphragm itself. This results in interference with the imaging light rays and causes the image to be less sharp than it can be. This value varies from lens to lens, but a a rough guide once you get past about f11 the definition starts falling off.

DPreview have a new "widget" in there test reports on lenses. This shows very graphical how the image quality falls off with an increase in aperture ( going from f4 to say f16)

Here's a link to the canon 50mm f1.4 review. Notice how the quality drops after about f7.1

http://www.dpreview.com/lensreviews/canon_50_1p4_c16/page4.asp.

However you need to temper this with the need for adequate DOF. sometimes the DOF is more important than absolute image quality. If however the required DOF is obtained at say f6.3 then there is no point in stopping down to f11.

If you are fortunate enough to have a iPhone there is a little app called PhotoCalc that will work out DOF for differnt cameras, lenses and apertures. All for £1.80
 
DiddyDave said:
:agree: except I think you misspelt 'diffraction' as 'detraction'

Only mentioning it as detraction is a word too!

DD
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Thanks DD. Yes is it a typo. should be diffraction, I was probably distracted
 
Chappers said:
Thanks DD. Yes is it a typo. should be diffraction, I was probably distracted
Click to expand...

:lol:

I don't normally bother with typos on TP - just thought the fact that the misspelling is a word too could confuse someone

:thumbs:

DD
 
OMG... This post has been such an eye opener for me... can anyone give me a link to a site which has good lens reviews... def want to see these graphical diagrams for my lenses... and need to get using that DoF calculater so I actually have figures for DoF in my head for my lenses... Im am so blown away by how this might improve the quality of my images... It's amazing how the basic rules you read about in basic books can be flawed!
 
Thanks for the responses everyone, made a good thread to read over my morning coffee :D

I must admit when I have taken images with my 10-20mm, at 10mm and F22 the resulting pictures do look quite soft, but not so much that they detract from the quality of the image (in my opinion, but then I am somewhat bias!)

I put it down to my RAW processing skill, but I'm going away for a long weekend to the lakes next week, so I'll give F8 a go and see how I get on :thumbs:
 
good link for lens reviews to see these diagrams you are talking about... especially canon lenses!?!?!

Thanks again... cant wait to get out and try only going to f11 and compairing it with f22 pics... will def be my next photography experiment!

M
 
markelliot said:
good link for lens reviews to see these diagrams you are talking about... especially canon lenses!?!?!

Thanks again... cant wait to get out and try only going to f11 and compairing it with f22 pics... will def be my next photography experiment!

M
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Do you have a shutter release and do you use mirror lock up? The shake caused by pressing the shutter button or the mirror actually flipping can unduelly affect how sharp the shots are as they can introduce some shake
 
markelliot said:
OMG... This post has been such an eye opener for me... can anyone give me a link to a site which has good lens reviews... def want to see these graphical diagrams for my lenses... and need to get using that DoF calculater so I actually have figures for DoF in my head for my lenses... Im am so blown away by how this might improve the quality of my images... It's amazing how the basic rules you read about in basic books can be flawed!
Click to expand...

Here are what I believe to be the best 2 sites:
http://www.slrgear.com/reviews/index.php
http://www.photozone.de/
There are others, DPReview has started a good lens review section but the range is limited at present.
 
I never use anyhting smaller than F16 for my landscape shots & very rarely go beyond F11...the crop sensors on digitals provide more inherent DOF than film cameras so the same rules need adjusting slightly.

Whenever I've used F22 ( a long time ago) it's always produced slightly soft images, certainly noticable over a F11 one.

simon
 
In my opinion it depends what you want in 'REAL' focus.

If theres a viaduct at the back of the frame, say 300 yds. and you want the stonework sharp, then focus on that.

If you focus at hyperfocal distance say (Dslr@17mm@f8@12ft) the viaduct will be soft.
 
Hi all

I did a test to evaluate the sharpness of both my lenses that I usually use for landscape my Sigma 15-30mm and canon 28 - 135 mm

I set the camera up on a tripod... a landscape of my home city of edinburgh from Blackford hill with a bench and bushes as some foreground interest... I shot pictures keeping the pic, focal length and focus the same only changing the apature in AV mode.

It was clear with both lenses that they seemed to peak in close up sharpness at about f8 to f 11... to be honest to my untrained eye and just using this scene rather than some sort of test card... it was impossible to tell any dif between f8 and f 11.... however f16 was soft and it amazed me how much softer f22 was...

Im off to print out some DoF charts for dif focal fengths for my camera and then going to pump the values into excel to give myself a wee pocket guide for each of my lenses...

Ive briefly looked at the tables already... and def think i'll be shooting much more of my landscapes at F11....

Thanks for this... I think this thread has been the first of many that will spur a real improvement in my photography! I cant believe they hardly mention this in books!

M
 
Hi again...

Sory to be a pest guys... could someone actually explain to me a bit more about what im looking at on the charts that are part of the reviews on the slrgear reviews page....

Especially the blur index one.

Thanks

M
 
markelliot said:
Hi again...

Sory to be a pest guys... could someone actually explain to me a bit more about what im looking at on the charts that are part of the reviews on the slrgear reviews page....

Especially the blur index one.

Thanks

M
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What I'd be looking for is a summary saying "This lens is at its sharpest between f5.6 and f11" (or whatever) and I would then use it within that range as much as possible.
 
I think i've kinda sussed from my test pics on sat that its sharpest between f8 and f11 and will now use them more for my landscapes... along with taking my tripod more... but that can be a pest at times as often my photography involves combining it with weekend walks or drives where I don't have the time for the whole tripod setup without ****ing off the fiancee to much... its a very fine ballance...

What I have done though is laminate wee cards I made up using the DoF tables ^^^ and rejiged them to suit my lenses and the 20, 28, 35 and 50mm FL's I normally shoot in... I think once I start using them I'll get a good idea in my head of my kit... its def what i need to do more... get to know my kit a bit better...

Somehow need to find more time for my photography!

M
 
Fabulous thread. You know how sometimes you can read and read and still not understand and then suddenly one quick sentence explains it all, well thats just happened to me. I actually get dof now.

Thanks all

Andy
 
dcash29 said:
In my opinion it depends what you want in 'REAL' focus.

If theres a viaduct at the back of the frame, say 300 yds. and you want the stonework sharp, then focus on that.

If you focus at hyperfocal distance say (Dslr@17mm@f8@12ft) the viaduct will be soft.
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I have to disagree there m8 :shake:

The point of a Hyperfocal Point is that everything beyond will be sharp too, it's just that if you just focussed on that viaduct you'd be 'wasting' some of the DoF available to you

In landscapes, the Hyperfocal distance is that which maximises the DoF use by bringing the nearest point of sharp focus closer to you without lessening the sharp in-focus area in the distance

DD
 
Can someone explain hyperfocal focusing to me practically... I've read it in a book and it goes on about focus marks on the lens... my lenses dont have the makings they show on the books...

If for instance you had a photo to take with a bench in the foreground at 4m away... how would you go about hyperfocal focusing?

Is it a technique you only need to use if you are using wider angle lenses... 28mm or wider as you get such a close foreground when composing... Im thinking the pebbles on a beach sort of example with a low point of view...

M
 
markelliot said:
Can someone explain hyperfocal focusing to me practically... I've read it in a book and it goes on about focus marks on the lens... my lenses dont have the makings they show on the books...
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It is much easier with the depth of field scales you get on prime lenses.

As I understand it hyperfocal focusing works like this.

*You decide what aperture you are going to use - say f8.
*You place the infinity mark just inside the f8 marking on the depth of field scale on your lens. (that way infinity will be in focus)
*Look at the other end of the scale to see if your nearest subject matter is within the other f8 mark.
*If it is, fire away. If not set to f11 and repeat.

With zoom lenses this is almost impossible, but a rough rule of thumb is to focus about 1/3 of the way into the picture. (Use the depth of field preview button to check, if you have one.:)
 
Quote:
Originally Posted by dcash29 View Post
In my opinion it depends what you want in 'REAL' focus.

If theres a viaduct at the back of the frame, say 300 yds. and you want the stonework sharp, then focus on that.

If you focus at hyperfocal distance say (Dslr@17mm@f8@12ft) the viaduct will be soft.


I have to disagree there m8

The point of a Hyperfocal Point is that everything beyond will be sharp too, it's just that if you just focussed on that viaduct you'd be 'wasting' some of the DoF available to you

In landscapes, the Hyperfocal distance is that which maximises the DoF use by bringing the nearest point of sharp focus closer to you without lessening the sharp in-focus area in the distance

DD
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They do say a picture never lies, and ive got them that prove what i'm saying.



Mark
Im unable to find at which point in the frame you focussed on in your tests
 
dcash29 said:
Quote:
Originally Posted by dcash29 View Post
In my opinion it depends what you want in 'REAL' focus.

If theres a viaduct at the back of the frame, say 300 yds. and you want the stonework sharp, then focus on that.

If you focus at hyperfocal distance say (Dslr@17mm@f8@12ft) the viaduct will be soft.



They do say a picture never lies, and ive got them that prove what i'm saying.



Mark
Im unable to find at which point in the frame you focussed on in your tests
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I've never posted my test pics so im unclear what you mean... I used a bench in the foreground...

You've lost me as to how you thought you would know where i'd focused on?

M
 
Mark

The section above was for someone else, i asked you the following

Where in the frame did you focus while testing your lens?

Dave
 
dcash29 said:
Quote:
Originally Posted by dcash29 View Post
In my opinion it depends what you want in 'REAL' focus.

If theres a viaduct at the back of the frame, say 300 yds. and you want the stonework sharp, then focus on that.

If you focus at hyperfocal distance say (Dslr@17mm@f8@12ft) the viaduct will be soft.



They do say a picture never lies, and ive got them that prove what i'm saying.
Click to expand...


Sorry still m8 - but either the rest of the world's physics is wrong or you've done something wrong (perhaps it's just a crap lens even :thinking: are you a Canon user :D)

Hyperfocal focussing is a fact, it's not subjective, so used correctly it will work - always

I have used it to great effect focussing only a few inches in front of my lens and getting sharp focus from less than 12" to the horizon every time I've wanted it, so God knows why you're saying it doesn't work :shrug:

DD
 
dcash29 said:
Mark

The section above was for someone else, i asked you the following

Where in the frame did you focus while testing your lens?

Dave
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Ah right sorry... In my test shots I focused on a bench about 5 m away from the camera set up...

Have I done the wrong thing....

Is there a test card I could use to test the lens?

Mark
 
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