...
class ModelWithDefaultStaticImage(models.Model):
image_file = models.ImageField(default='img.png')
class officeUsers(models.Model):
....
photo = models.ImageField(verbose_name='Фотография',
upload_to='photos/%Y/%m/%d',
blank=True)
....
<div class="user_img">
<img src="{% if user.photo %}{{ user.photo.url }}{% else %}{% static 'sysadmins/img/avatar.jpg' %}{% endif %}" alt="">
</div>