Laravel 5.4: How to upload an image to the server with the user that uploaded it?

I am newbie learning laravel and i am trying to upload an image but i also need the user who uploaded the image. Here is my photos table

`public function up()
    {
        Schema::create('photos', function (Blueprint $table) {
            $table->increments('id');
            $table->unsignedinteger('user_id')->index();
            $table->string('title');
            $table->string('image');
            $table->timestamps();
        });
    }

    public function down()
    {
        Schema::dropIfExists('photos');
    }`

This is my Photos model:

protected $fillable = [
    'user_id','title','image'
];

public function user()
{
    return $this->belongsTo(User::class, 'user_id');
}

And this is my controller:

public function upload(Request $request)// store the image 
{             
    $user=Auth::user()->id;
    $this->validate($request, [  
        'title' => 'required',
        'image' => 'required|image|mimes:jpeg,png,jpg,gif,svg|max:2048',   
    ]);
    $input['image'] = time().'.'.$request->image->getClientOriginalExtension();
    $request->image->move(public_path('images'), $input['image']);
    $input['title'] = $request->title;    

    Photos::create($input);
    return back()
    ->with('success','Image Uploaded successfully.')
    ->with($user);

}

The error i get is :SQLSTATE[HY000]: General error: 1364 Field 'user_id' doesn't have a default value (SQL: insert intophotos(image,title,updated_at,created_at) The uploading is working without having a user_id row. Can you please help me what did I do wrong?

via Chebli Mohamed