Focus issues

AMac

AMac

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Name
Alex
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Hi,
Sorry if this is not the best place to post this question :)
I took this pic a few weeks ago, when I was looking at it a thought it looked a bit soft, well very soft. At first I thought it might be camera shake, but I have looked at some others now and at 100% they all look soft!
So today I quickly took the other images attached. The bottom of the vase looks soft, whist the print in the other pic looks ok.
It is taken on a Canon 550D with 17-40 canon lens. With just the centre focus active. From a raw image, which has been exported form Lightroom with sharpen on output for screen.
The display in the view finder of the camera has gone a funny, so now I am questioning if the camera has gone faulty.
I dont think I am over critical of the sharpness, but it might be now I have seen something I am seeing things not there.
Many thanks for any help or advice.
 
The text on the paper is a good test, but not much use here as it's shot through glass. The base of vase being soft could be explained by shallow DoF. What aperture was it shot at? If wide open, how does it look a few stops down?
 
try some shots on a tripod and manual focus...to sort out the lens and dof suggestions
then set the lens on auto again and with the tripod take some shots with varying apertures
remember kit lenses arent good at all settings...at least i dont think mine is...
for close up and detail work use a prime

i have in the past left my lens on manual focus and merrily went off thinking it was on auto...so i got shots like these
 
Hi thanks for getting back to me, the shot of the fungus at f4/50, do you think it might be dof? and the vase as f7.2/160 so I cant see it being dof, as the bottom of the vase is only 150mm away from the top edge.
I could try again today, at different f stops and the manual focus.
The lens is an L lens, so I thought it should be sharper which I have had for some years, it is one of those things now I have seen it, I cant get it out of my head!
I will try some more today on the tripod to make sure and see, funny how the text one looks sort of ok?
Thanks for your help.
 
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The images are just far too small to evaluate. If you are concerned about the sharpness of your images, the first thing to do would be to post up images at the full resolution, as these are really small. Upload the full resolution pics to Flickr and post a link to them.
 
The vase/bowl shot, even at this low resolution is focused on the soil in the bowl, just behind the rim, so the very front of the bowl is out of focus, so this is user error (unless you wanted the soil to the in focus at the expense of the bowl).
 
Hi, sorry I have been way laid with jobs, and have not had a chance yet. I just checked the image in Digital Photo professional, the single focus point is shown on the very front of the bowl, so now I am wondering if something is wrong. Once I get a moment I will get some higher resolution images up. Thank for your help
 
The bottom of the vase is out of focus because it is not within the depth of field of the shot. How far were you from the vase? Even up to 2 or 3 metres away, you're only talking about a couple of cm depth of field at f7.6/160.
 
There's nothing wrong with the camera in terms of sharpness.

As for AF.. where on the front did you focus? It appears to be sharpest at the top of the birdcage. If that's where you focused, then it's fine.. The rest is, as ghoti said, out of focus due to a shallow depth of field.
 
Hi guys, yes you are correct it is on the bird cage, I didn't realise that depth of field would be so small, I normaly do landscape stuff, it was when I was taking some fugue out on a walk, it looked so soft, and very soft at 100%. But I guess user error ha ha, normally is.
You know what it is like, once you think something is wrong you cant get it out of your head.
I will have to practice some more!
Thanks for your help.
 
AMac said:
Oh one last general thought, I always use just the centre focus point. I always worry using all of them, it might lock on to the wrong area.
What does everyone else use?
Cheers
Click to expand...

centre only on auto
but really..and i am coming back to this really seriously...
manual...then the focus stays where you want it...
it shouldnt be a problem with slrs as they always had manual focus lenses...film or digital
 
DoF gets shallower as you get closer to a subject so probably why you weren't expecting to need a smaller aperture.

AMac said:
Oh one last general thought, I always use just the centre focus point. I always worry using all of them, it might lock on to the wrong area.
What does everyone else use?
Cheers
Click to expand...

Yeah, I tend to use the centre one too (although it does vary depending on the scenario). Just be aware that if you are recomposing after locking the focus, you need to keep in the same plane of focus as you can easily throw it off by moving forwards or backwards slightly, particularly with shallow DoF.
 
AMac said:
Oh one last general thought, I always use just the centre focus point. I always worry using all of them, it might lock on to the wrong area.
What does everyone else use?
Cheers
Click to expand...


For simple subjects like this, I'd use a singel AF piont. Usually for still life though, I'd be on a tripod, and using manual focus and a zoomed in live view to focus.
 
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