Ok now I got it to return the id’s. . using:
<?php $images = get_field('acf-gallery'); if( $images ): ?>
<?php foreach( $images as $image ): ?>
<?php echo $image['id']; ?>,
<?php endforeach; ?>
<?php endif; ?>
The above gets me this output:
<div class="textwidget">
315,
314,
305,
306,
308,
309,
307,
313,
311,
312,
</div>
