Hi @alejandrom6594753 ,

In my opinion your exposure is fine. Your photos have a white balance issue. They have a purple tint.

Details are lost in the highlight. In a setting like this you needed a fill light to soften the sun's highlight.

The photos are noisy when zoomed. Also they have color fringing on the edges. 

Best wishes

Jacquelin

This is a nice series, and probably worth re-shooting. I agree with the assessment of @Nancy OShea regarding lighting and angles. The areas of the book where the sunlight hits are completely blownout. A shade on that window would help - or just wait until the direct sun passes. Additionally, you have what appear to be sensor hotspots, which seem to be more obvious in the darker parts of the image. See those bright white spots? Those are hot pixels, or dead spots on your sensor. Read more about it here: https://www.youtube.com/watch?v=WSgWixX8G3g

I like the subject very much.

Uneven lighting.  Natural light from the window is casting harsh sunrays on some parts (book pages, knees) and not enough light on others.

I think you have some angular problems, too.  Photos should be anchored horizontally or vertically. Diagonals can be used to imply depth or distance in a scene but it only works when contrasted by straight anchors.

Hope that helps.