Beginner Soft focus

Nostromo

Nostromo

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Dominic
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Could somebody please explain what causes soft focus? I've taken many a photo that look fine until I zoom in, then see that it's just a little bit out. I've also taken a series of photos with the same setting but slightly different focal lengths, where some are fine and others are soft.
It drives me up the wall sometimes. I'm just a hobbyist but would still like a sharp shot. What is annoying is that I know my camera and lens (t3 with kit lens) can take a sharp shot, (I not expecting pro quality by the way).
 
On the shots that are soft. Can you see any part that is in focus. If so is it in front or behind the spot you focused on and is this the same on most of the OFF shots. If it is you may need to do a micro adjust If you can on the T3.
 
It can be a number of different things, more obvious ones are:

1. The lens, cheaper lenses tend to be softer when viewed at 100% and this varies depending on focal length
2. Focus, AF systems tend not to get it 100% right every time, small errors don't show up at normal viewing but at 100% they show up
3. Shutter speed vs. focal length, if the shutter speed drops too low it can be a bit blurry

Might be helpful to post some shots :)
 
Post one of your shots up here with the EXIF data and some one will be able to help.

Dave
 
Thanks for the replies, i understand that a kit lens won't give the best of quality and that the camera body is getting on a bit, so will be up grading the lens at some point (money is tight at the moment) in the future.

vetonbike said:
On the shots that are soft. Can you see any part that is in focus. If so is it in front or behind the spot you focused on and is this the same on most of the OFF shots. If it is you may need to do a micro adjust If you can on the T3.
Click to expand...

This was my first thought, but as far as i can tell the whole image is out,

Nawty said:
It can be a number of different things, more obvious ones are:

1. The lens, cheaper lenses tend to be softer when viewed at 100% and this varies depending on focal length
2. Focus, AF systems tend not to get it 100% right every time, small errors don't show up at normal viewing but at 100% they show up
3. Shutter speed vs. focal length, if the shutter speed drops too low it can be a bit blurry

Might be helpful to post some shots :)
Click to expand...

I will up load some shots.
The cat and dog (which i think are sharper) were also taken in raw, adjusted, with a smallish crop. The cat (Barny) i think is focused on the left eye and the dog (Ruby) also the left eye.

The shot of the Rose (which is soft) was taken in raw, with center point focus and adjusted, with a small crop and converted into jpeg.
The Tulip was taken as a jpeg, center point focus and a small crop.
Sorry it's taken so long to reply, my internet went back to the dark ages. It was like having dial up again. That's one of the downfalls of living in the countryside.View attachment 38864 View attachment 38865 View attachment 38866 View attachment 38867
 
cant see exof data on any of these but could simply be that most lenses are at there sharpest when stopped down a couple of stops , even more so with kit lenses too which can be soft and short and long end of there range. normally stepping down to around f/8 will give you the sharpest of shots.
also rule of thumb is shutter speed should be faster than focal length. and when using a crop sensor you have to multply the crop factor first to get the focal length then you can work out the speed.
so for instance on a crop sensor standard 18-55 kit lens the longest focal length is around 88 so if you have no image stablization then for handheld you need around 1/80th and above shutter speed. below that and even the tiniest wobble can convert to an image being 99% sharp instead of 100% sharp.
so at full length shoot f/8 above 1/80th sec and see how you get on.
at the 18 mm end again around f5.6 to f/8 and shoot around 1/30 sec and above . also any filters you use ( if you do use any ) can degrade image quality by a little if they are budget filters ) which can also result in a tiny amount of image quality loss.
 
Difficult to tell at these resolutions - if you can post crops that would be handy and also the shutter speeds/aperture.

The other thing is that as you get closer to the subject you need to have a higher shutter speed because as you magnify the subject you also magnify any wobble.

Barney and Ruby look like it was sunny and the shutter speed will be high enough to be very sharp, the roses are darker and don't look like they were in full light so either the ISO has gone up or the shutter speed has gone down, either of which will cause softening.
 
Nawty said:
Difficult to tell at these resolutions - if you can post crops that would be handy and also the shutter speeds/aperture.

The other thing is that as you get closer to the subject you need to have a higher shutter speed because as you magnify the subject you also magnify any wobble.

Barney and Ruby look like it was sunny and the shutter speed will be high enough to be very sharp, the roses are darker and don't look like they were in full light so either the ISO has gone up or the shutter speed has gone down, either of which will cause softening.
Click to expand...

You are right that Barny and Ruby were taken in sun light and the flowers were in light shade.
 
Agreed, the shade doesn't help. 1/60s at a 43mm focal length on a crop body is pushing it slightly - I'd be more confident personally if the shutter speed was double that or more.

Also remember (although this isn't why the rose shot looks soft) that when you focus close to an object the amount of that object in focus will be lower.
 
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