Why aren't these shots in focus?

crotonmark

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Help Please !!
Shooting with a Canon T4i
Using a 35/105 mm lens
In all cases I used a center focus point
In all cases the camera beeped to tell me it was in focus
In all cases when I look at the photos they don't seem sharp
What am I doing wrong?
This is starting to drive me mad

thanks - Mark $IMG_0890.jpg$IMG_0889.jpg$IMG_0886.jpg$IMG_0891.jpg
 
It's not out of focus, it's motion blur. Unless you were using a tripod your shutter speed was far too slow. I only looked at a couple of them but the shutter speed was 1/13 second which is much to slow to shoot hand-held. You were only at ISO 200 and didn't use a flash, so my recommendation would be to up the ISO to whatever you can stand which will allow you to use a faster shutter speed.
 
Probably because you moved during a slow shutter speed.

What was your shutter speed and aperture on these?
 
Focal Length: 105mm
Exposure Time: 0.077 s (1/13)
ISO equiv: 200


Focal Length: 35mm
Aperture: f/5.6
Exposure Time: 0.100 s (1/10)
ISO equiv: 200


Focal Length: 35mm
Aperture: f/3.5
Exposure Time: 0.040 s (1/25)
ISO equiv: 200


Focal Length: 35mm
Aperture: f/5.6
Exposure Time: 0.077 s (1/13)
ISO equiv: 200
 
What you are seeing is small photographer induced camera motion and is more commonly termed 'camera shake'. 'Motion blur' is blur induced by subject movement.

The rule of thumb for hand-held shutter speed is 1/focal length of the lens.

At 35 mm at least 1/35 and good camera holding technique is needed to minimize the chances of camera shake blur, but a somewhat faster shutter speed, say 1/60 is better. At 105 mm use at least 1/105 for your shutter speed, but somewhat faster, 1/125 or more is better.
 
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but if my largest aperture is F3.5 then why did the camera choose such a slow shutter speed (ok I guess there wasn't enough light??) Should I have just upped the ISO to 400?
I am not being dense - just very unsure of myself and disappointed.
 
Don't be disappointed. You'll get this right. Were you in aperture priority mode? If so, and you're ISO is NOT auto, the camera is going to do what it has to to get the exposure level correct. in this case, all it could do was decrease the shutter speed. You could mitigate that by upping the ISO, or perhaps by allowing some degree of auto ISO, but different cameras will deal with that setting slightly differently. As a rule, try to keep your shutter speed at or faster than 1/focal length. Make sense?
 
If you grab a book about photography it might help. It helps to understand "stops". So if you raise your ISO to 400 ie 1 stop, you would double your shutter speed. Take the second picture for example, at iso 200 your shutter was 1/10th, at iso 400 it would be 1/20th at iso 800 it would be 1/40. That is a basic explanation....
 
Yes, increasing the ISO makes the image sensor seem more sensitive to light. More light means you don't need to leave the shutter open as long to make a good exposure.
Camera Exposure: Aperture, ISO & Shutter Speed
Understanding Camera Lenses
Tutorials – Sharpness
Understanding Camera Autofocus

A 'stop' is a doubleing or a halving.
Changing from ISO 200 to ISO 400 is one stop. ISO 400 apparently doubles the amount of light. (Actually, the image sensor electronics just use different amplifier circuits.)

A stop of shutter speed would be 1/25 to 1/50, or 1/30 to 1/60. But with a faster shutter speed, less light is let in because the shutter is open for 1/2 as long.

By increasing the light 1 stop by changing the ISO, and decreasing the light 1 stop by changing the shutter speed, the total amount of light that makes the exposurestays the same. +1-1 = 0

Lens aperture can also be changed in 'stops', but the amount of light the lens aperture lets in or blocks is determined by the area of the lens aperture, not by it's diameter.

consequently x2 or /2 doesn't apply, the square root of 2 applies (about 1.4142). That is why full stops of lens aperture are f/1, f/1.4, f/2, f/2.8, f/5.6.
f/1 x 1.4142 = 1.4142is rounded to f/1.4........ NOTE: f/1.4 lets in 1/2 as much light as f/1 does.
f/1.4 x 1.4142 = 1.98 is rounded to f/2
f/2 x 1.4142 = 2.83 is rounded to f/2.8 .......NOTE: f/2 lets in 2x more light than f/2.8 does.
etc.

Most of today's DSLR camera are set by default to be adjustable in 1/3 stop increments.

Typical one-third-stop f-number scale (the green backed numbers are the classic full stop steps)

f/No.0.70.80.91.01.11.21.41.61.822.22.52.83.23.544.55.05.66.37.1891011131416182022

So, f/1.8 to 2 is 1/3 of a stop. f/1.8 to f/2.2 is 2/3 of a stop. f/1.8 to f/2.5 is a full stop.
 
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I was in Aperture Priority mode. Someone told me to try to understand aperture mode first so I am (badly). My ISO is not on Auto. Camera is the Rebel T4i (I know something you all here would never buy) It was all I could afford and it is more than I can handle.
What I don't understand is this - should I have shut down the aperture to force the camera to increase the shutter speed??

thanks
 
Dude... can I give you a great piece of advice??? Pick up the book Understanding Exposure by Bryan Peterson... This book will explain the relationship between ISO, Shutter Speed, and Aperture, and it is worth every red cent. Read it from cover to cover, and I promise, you will come out a better photographer. I have read it three times, and I plan on reading it again, as a refresher... I have learned more from this single book, than probably the other 20 I have read on photography...
 
Sirashley said:
Dude... can I give you a great piece of advice??? Pick up the book Understanding Exposure by Bryan Peterson... This book will explain the relationship between ISO, Shutter Speed, and Aperture, and it is worth every red cent. Read it from cover to cover, and I promise, you will come out a better photographer. I have read it three times, and I plan on reading it again, as a refresher... I have learned more from this single book, than probably the other 20 I have read on photography...

Yes I have this book and I am working my way thru it. The problem is I need to use the camera before I have gotten thru the book!!
 
should I have shut down the aperture to force the camera to increase the shutter speed??
No, that is backwards.

Making the lens aperture smaller lets in less light, so the shutter has to be slower (open longer) for enough light to fall on the image sensor to make a good exposure.
A shutter speed of 1/200 is a decrease (open 1/2 as long, lets in less light) from a shutter speed of 1/100.
 
KmH said:
No, that is backwards.

Making the lens aperture smaller lets in less light, so the shutter has to be slower (open longer) for enough light to fall on the image sensor to make a good exposure.

So all I could have done here was increase the ISO or use a flash?
 

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