Hi Danijel,

I think that its not possible. May be you can download the picture and then see in full size in your computer.

Regards,

Juan José - Ing ADHOC

Juan thanks for your answer. I cannot believe that Odoo is so user-unfriendly at this functionality.... pictures are useless then. When I go to business partner I wanna see the picture of what he looks like. Totally unacceptable, but that's just the way it is I guess....

EDIT: I checked the log, Odoo resizes image to 128x128, so even if you managed to click on the picture, the size would remain the same. Such a pity...

Hello Daniel, 
Are you talking about Customer in backend ? 
If yes, I'm not sure that is really a need for many peoples and so a user-unfriendly  behavior !
But if you want really do that, you can always add this option updating/extending the widget FieldBinaryImage.

if (this.options.click_fullsize) {
            field = 'image';
            url = this.session.url('/web/binary/image', {
                                        model: this.view.dataset.model,
                                        id: id,
                                        field: field,
                                        t: (new Date().getTime()),
            });
            $img.attr('onclick', _.str.sprintf("window.open('%s')", url));
        }

And so, inherit Qweb template res partner form and replace image by 

<field name="image" widget="image" class="oe_left oe_avatar" options="{&quot;preview_image&quot;: &quot;image_medium&quot;, &quot;size&quot;: [90, 90], &quot;click_fullsize&quot;: True}"/>

But what is your real usecase? It's an avatar, so it small by default ...