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jenodorf

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Name
Ian
Edit My Images
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Hi

semi retirement etc has enabled me to take on a new project/learning curve!.

When I take landscapes either close up or distant is blurred.

I assumed thiswas depth of field issue so set up my camera on a tripod with an ISO of 200 pointing at my garden, Canvas seat in the foreground and flowers in the distance.

I then selected the Af setting and took a series of images from the maximum to the minimum fstop.

All are out of focus. Is it because my Canon lens has a low max f setting?

have a canon eos 400d camera with an EF-s18-55mm lens?

In Adobe Bridge it tells me that I have:

f-stop: f/9
aperture value: f/9
max aperture valuef/4.5

lens: EFS-S18-55mm f/3.5-5.6


Does this mean that the maximum aperture that can be used is 5.6 despite the camera display showing much higher?

thanks

Ian
 
The maximum aperture of your lens will preduce the shallowest DOF.
The variation in maximum aperture, denoted by the f/3.5-5.6, is because the longest focal length has an impact on maximum aperture that can be used.
Some sample pictures showing what you tried would be very helpful.
How far into the picture were you focusing?
Here's some reading on hyperfocal distance which may be of interest: linky
 
Matblack said:
I find f numbers confusing too, crank the apature down to the highest f number and try a shot like that, the DOF is largest at the highest f numbers not the lowest . Try f22 and see what that give you :)

MB
Click to expand...

f/22 will look worse than f/11.

Beyond a certain point you'll get diffraction rearing it's ugly head and softening your photos.

Can you post some examples? Indicate in the examples where you were focussing as well. If you don't know, then that's half the problem. You should be using spot focus or manual focus and setting the focus to a specific point in the scene that will give you maximum depth of field around the objects you want in focus.

Edit:
Quick and dirty guide. The f number is a ratio of the effective aperture to the focal length of the lens.

The aperture is described by the number. f/22 means the aperture is the focal length divided by 22. Therefore f/1 is wider than f/22. The lower the number, the wider the aperture, the faster the shutter speed and the shallower the depth of field.
 
jenodorf said:
Hi

semi retirement etc has enabled me to take on a new project/learning curve!.

When I take landscapes either close up or distant is blurred.

I assumed thiswas depth of field issue so set up my camera on a tripod with an ISO of 200 pointing at my garden, Canvas seat in the foreground and flowers in the distance.

I then selected the Af setting and took a series of images from the maximum to the minimum fstop.

All are out of focus. Is it because my Canon lens has a low max f setting?

have a canon eos 400d camera with an EF-s18-55mm lens?

In Adobe Bridge it tells me that I have:

f-stop: f/9
aperture value: f/9
max aperture valuef/4.5

lens: EFS-S18-55mm f/3.5-5.6


Does this mean that the maximum aperture that can be used is 5.6 despite the camera display showing much higher?

thanks

Ian
Click to expand...

Ian, you may find this site helpful when trying to calculate what's going to be acceptable focus : http://www.dofmaster.com/dofjs.html

......and welcome to TP.
 
Welcome to TP Ian :)

You say you have a focus problem, but then talk only about f/numbers. What are you focusing on, with which method, and what is your shutter speed?

Post a pic with that info and you'll get the answer ;)
 
When you done your test, was the autofocus on?

At 18mm, an aperture of f9 to f11 will keep things pretty sharp from front to back, but do not focus too close to the camera.
 
Hi

thanks one and all for the helpful comments, I suspect I may just be looking for the "perfection" photograph.

For the past few (uncountable years) I've been heavily involved in Website design and vector graphics etc where everything is perfectly aligned and in focus no matter how bog or small you make it.

Promising my boss/better half to slow down has encouraged me to expand my knowledge and (rather than let clients supply images ans spend hours in photoshop getting them right) try to take the photosd myself.

Always beed a keen snapper but now I want to learn a bit more. Perhaps I shouldn't be looking to have everything in focus but rather make sure what I want is perfectly in focus?

I always view at 100% in ACR or Photshop but again I'm beginning to feel this is an error.

In the words of the great Eccles "all rather confusing really"

thanks one and all

Ian
 
Many people spend fortunes on the fastest lenses available so they can put as much as they can out of focus whilst keeping the subject in sharp focus. To keep everything in focus is virtually impossible with all but the widest angle lenses.
I'd suggest embracing the OOF areas as a blessing, they help draw the eye to the subject of the photograph and reduce any distracting elements.
 
jenodorf said:
Hi

thanks one and all for the helpful comments, I suspect I may just be looking for the "perfection" photograph.

For the past few (uncountable years) I've been heavily involved in Website design and vector graphics etc where everything is perfectly aligned and in focus no matter how bog or small you make it.

Promising my boss/better half to slow down has encouraged me to expand my knowledge and (rather than let clients supply images ans spend hours in photoshop getting them right) try to take the photosd myself.

Always beed a keen snapper but now I want to learn a bit more. Perhaps I shouldn't be looking to have everything in focus but rather make sure what I want is perfectly in focus?

I always view at 100% in ACR or Photshop but again I'm beginning to feel this is an error.
In the words of the great Eccles "all rather confusing really"

thanks one and all

Ian
Click to expand...

"I always view at 100% in ACR or Photshop but again I'm beginning to feel this is an error."

Yes, an error. Nothing will ever look good at that size. Normal photographic standards are based on an average print, viewed at an average distance. Like an A4 print viewed from about two feet.

What you are doing is called 'pixel peeping' and you do it (we all do it) because it's so easy with digital. It always leads to disappointment and frustration, investment in ever more expensive kit, followed by yet more disappointment etc etc :D
 
jenodorf said:
...
I then selected the Af setting and took a series of images from the maximum to the minimum fstop.

All are out of focus.
Click to expand...
Repeat this test in a park. Find a tree, standing alone in the middle of the park or of a field - stand 30 feet from it and autofocus on it, then switch the lens to manual focus and put it on the tripod. Take photos at various f-stops. The tree should always be in focus, but nearer & further objects (grass in front, clouds in the sky) should show less focus at f/2.8 and more focus at f/8 & f/11.

Try different f-stops at different distances from the tree, but always focus on the tree first.

See some of these articles:
http://www.google.com/search?q=depth+of+field
 
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