Using images with Flex-objects

Hi, I’m having a look at Flex-objects as I think it might suit an artist’s portfolio I’m building - there are artworks plus related prints for sale so I thought I could have a directory of artworks, and a directory of prints and relate the two: if I look at an artwork I want to see which size prints might be available. But I’d also like to just show a listing of prints. So it seems a good fit.

I’m struggling with the image path. I’ve added the image upload field, and I can see where grav is storing the image but when I try to show it I’m getting an empty string.

my twig is:
{% if object.item_image %}
show the image - and this if is successful because i see the alt tag
{% endif %}

within the if I’ve tried:
<img src="{{ object.item_image|first }}" alt="{{ object.title }}" >
or
<img src="{{ object.item_image.media|first }}" alt="{{ object.title }}" >
or
<img src="{{ object.item_image.url }}" alt="{{ object.title }}" >
or
<img src="{{ object.item_image.media.url }}" alt="{{ object.title }}" >

with no luck - what am I missing?