Each image is out of focus. Some have slight fringing along the edges of branches and leaves. You probably needed to use a faster shutter speed, particularly when shooting these types of subjects outdoors, since the slightest breeze will cause them to move. The first image should also have been shot with a smaller aperture to increase the DOF and bring more of the buds in focus.
Out of focus and noisy. You need to focus correctly!
Out of focus and noisy. You need to focus correctly! In addition, the picture is slightly underexposed and could get a push of vibrancy.
Guess: Out of focus and noisy. You need to focus correctly!
It's missing also contrast and could get a little of vibrancy.
Still soft, but you're getting nearer. However, the noise level is much too high, so you cannot sharpen without amplifying that noise.
I've seen that your ISO is quite high (250-400), for a crop factor camera that is quite high. The DOF is mostly too small. You see that good with the last picture, where you missed the sharpness layer by not too much for some seeds, but most of the seed is out of focus.
Maybe you need to calibrate your lens focussing. Or your lens is not sharp enough for that camera.
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