Techincal Problems of my uploaded images

Caffe Latte:

Noise (arrow), bluish light (ok, that can be nice, but I think it does not add here something) strange ard edges between the blue and the white in the milk froth. In addition the histogram shows that the picture is kind of underexposed. Also the composition is not good. 

Adding a little bit more of the cup's shadow would make it more usable for potential buyers.

For the boat:

There are artifacts noticable in the image:

I think it's also oversaturated. And for the composition, I would crop out the light pole at the left and edit out the cable. unfortuneatly the building is somehow weird interconnected with the fore. 

The first would pile is underexposed (one to 1.5 stops) otherwise it would be a nice texture. When taking such pictures,

1. set your camera to manual mode
2. set the "correct" exposure as measured
3. use exposition brackets and choose the best exposed picture. If you use a tripod, you may even be able to combine different exposures.

The wood doesn't move fast, so take your time to get the correct composition out of the camera. Check the pickture at 100% on the camera screen for disturbing elements especially around your main subject. 

The second pile is really badly composed, besides being also underexposed.

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Fabian, I see something that I see often on Social media, no offense.  People check the density of their images with monitors that are too bright.  If the monitor is bright, which is most folks' preference, and they determine the lightness/darkness with software.  They inevitably will darken down too much.  

As an example, my monitor is at a setting of brightness close to the middle.  I went to the Apple store and dealt with a helper there.  The first thing he did, as he hit the brightness button to its max was to ask "what's up with your monitor?"  I said " Oh, well, it's calibrated", he quickly apologized.  Calibrating is great but, at least we can turn down the brightness to set photos density.  This applies to the first three.  The boat seems to be better in the density department.  Great shot.  Wish you well.

There may be more detailed technical issues visible with close inspection but let's look at the composition because that comes under Technical issues too.

* In the first image, the composition of the cup, and the out of focus background is nice. But there is a blurry object that seems to serve no purpose behind the cup, and there seems to be confusing lighting.

* In the second image there is one piece of wood that is different. Why, what is its story? And the strands of twig at the corner seem unplanned.

* The stump and woodpile seem too tightly cropped for general commercial use. I'd want to see the whole of both. 

* The boat is nice but the power line is not. Also the boat randomly overlaps a building: what is the relationship between boat and building? What are the two buildings lit differently and what is their story?