Hey Will,
It’s possible to send photos from an attachment field in the Sendgrid block as long as there’s just one photo uploaded per attachment cell. To do so, first add a formula field to pull the URL from the attachment field:
MID({attachment}, FIND('dl.airtable.com', {attachment}), LEN({attachment}) - FIND('dl.airtable.com', {attachment}))
Then, as long as your Sendgrid block is configured to Send as HTML,
you can reference the formula field to display the image:
<img src="{Attachment URL Formula}">
Does this help?