snapbridge – Nikon D5600 Photos come out blurry when zoomed

I am a beginner at photography and recently got a camera (Nikon D5600). I watched a few videos on how to use it but I am still finding it difficult to operate. I have several questions but the main one is how to make pictures sharper?

I have an iPhone X which takes better pictures, when I zoom in I can see the image clearly, however when I zoom in on a photo with my camera, everything is kind of blurry. The photos I’m using as comparison are the ones from SnapBridge app. I will also give my usual settings if needed.

Does anyone have any tips on how to learn the best way to take pictures or how to at least make my pictures a higher resolution?
Picture from iPhone

Picture from Nikon D5600

timelapse – During interval timer shooting, NIKON D5600 overexposes photos randomly

I am having an issue with my camera. At random, it will overexpose photos during interval timer shooting. It’s generally fine at the beginning, but as time goes on, there are more and more overexposed shots. The time on those shots is the same as on the ones that are properly exposed.

Here’s my last timelapse, you can see the overexposed shots:

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I am thinking that either the aperture is not being set properly on the lens, or the shutter is broken. How can I diagnose this so that I can know if I need to get anything fixed? It never happened when I was taking pictures normally.

autofocus – Nikon D5600: AF area mode (no of focus points ) doesn’t work in any of manual mode (aperture, shutter, manual) for any fou

AF-area mode (no of focus points 9, 21, 39 ) doesn’t seem to work in manual modes (aperture priority, shutter priority, manual) for any focus mode (AF-A, AF-C), only it focus at centre with a single focus point)

While If I select Auto-area AF in AF-area mode as shown in picture, then auto focus (more than one focus points) works well.

Could you please explain that is it a problem in my newly bought dslr or it is like that way only ?

enter image description here

Exposure value changes but image brightness remains same (Nikon D5600, Manual Mode)

I have Nikon D5600. I have tried several times in Manual mode to change the exposure value by pressing the exposure button (given in the top control) and rotating the dial. I can see that the exposure value changes (plus or minus) but once I click the photo, the brightness of the photos remain same (although if you check the details, the exposure value is equal to the value that I set).

On the other hand, if I change the exposure value by pressing the info i button and then change the value using touch screen then, the brightness of the photos changes as per the set values.

Why brightness/exposure remains same (even the values show in data differ) if you change exposure settings using +/- dedicated button?

150-600 mm lens for Nikon D5600

I have checked Sigma and Tamron 150-600 which are mentioned (in Amazon) as compatible with Nikon D5600. The reason why I am posting is to know whether to go with any of these lens with this camera or buy a Full-Frame camera instead.

I want this lens for wildlife photography though I don’t have much experience with the camera and lens suitable for this. Nikon D5600 does have some limitations with low-light photos. Moving ISO beyond 500, it adds lot of noise. Even Adobe Lightroom is able to suppress partially.

For full-frame camera, I want to go with Sony Alpha sIII.

smartphone – Does NFC in Nikon D-5600 have any purpose beyond pairing?

I noticed that having Bluetooth always on drains the camera battery even though it’s Bluetooth Low Energy. The camera also has an NFC antenna and I’ve seen other photographers use that to trigger WiFi transfer.

On Nikon D-5600 I only found examples using it for initial pairing, but placing my phone next to the camera does not seem to enable Bluetooth or WiFi if they were shut off in the camera settings.

Is there any other purpose for NFC in Nikon D-5600 than the initial pairing with camera, which can be done without NFC?