User larger image on product page

I think i have the correct code in Views > Displays > Show

But I don't know exactly what to change to use a larger image for the product image.

^{</div>
<div id="hikashop_product_left_part" class="hikashop_product_left_part">
<div id="hikashop_product_image_main" >
<div id="hikashop_main_image_div" class="hikashop_main_image_div">
<?php
$image = null;
if(!empty($this->element->images)){
$image = reset($this->element->images);
}
if(!$this->config->get('thumbnail')){
if(!empty($image)){
echo '<img src="'.$this->image->uploadFolder_url.$image->file_path.'" alt="'.$image->file_name.'" id="hikashop_main_image" style="margin-top:10px;margin-bottom:10px;display:inline-block;vertical-align:middle" />';
}
}else{
$height = $this->config->get('thumbnail_y');
$style='';
if(!empty($this->element->images) && count($this->element->images)>1){
if(!empty($height)){
$style=' style="height:'.($height+5).'px;"';
}
} ?>
<div class="hikashop_product_main_image_thumb" id="hikashop_main_image_thumb_div" <?php echo $style;?> >
<?php echo $this->image->display(@$image->file_path,true,@$image->file_name,'id="hikashop_main_image" style="margin-top:10px;margin-bottom:10px;display:inline-block;vertical-align:middle"','id="hikashop_main_image_link"'); ?>
</div>
<?php }
?>
</div><div id="hikashop_small_image_div" class="hikashop_small_image_div"><?php
if(!empty($this->element->images) && count($this->element->images)>1){
foreach($this->element->images as $image){
echo $this->image->display($image->file_path,'hikashop_main_image',$image->file_name,'class="hikashop_child_image"');
}
}
?>
</div>
</div>
</div>}

Could you be more specific. Sorry I don't know exactly which tab file you are referring to. Could you please reference something more concrete so I can find the exact place to make the changes. Not a programmer but trying to understand.