clone imagick object - wrong output

Question

Following code produces entirely different image clone. Let me show you:

$image = 'image_input.jpg';
$im = new Imagick();

$im->pingimage($image);
$im->readimage($image);

$im_clone = clone $im;

$im_clone->writeimage('image_output.jpg');
$im_clone->clear();
$im->clear();

Answer 1

This works fine with PHP 5.6:

<?php
$image = new Imagick();
$image->readimage('input.jpg');

$im_clone = clone $image;
$im_clone->writeimage('result.jpg');
?>