Luna 3 did something as complicated as you thought: It took photos on a film, processed it in a kind of onboard minilab, and then scanned and radioed it back home in analog way not unlike an old fax.
Funniest part was that Soviets didn't have the technology of radiation-hardened film, but Americans did. They used it against Soviets in high-altitude spy balloons. This program was quite a failure for Americans, but Soviets retrieved some of those balloons before they spent their precious cargo and repurposed the film for a space mission. Manufactured in the USA, sent to the Moon by Soviet Russia! You can read more about Luna 3 here
If you ask about similarities to raw "format", analog picture transmission is more like uncompressed bitmap than raw dump from a typical modern sensor. Raw data is not a format, every sensor makes it's own and there are no metadata like end-of-line markers or info about what sensel represents which color. Analog transmission (as in fax or TV) usually is way more structured, eg time to return the scanning beam to the beginning of the next line makes a natural end-of-line marker, or a special tone is used to denote that, which among others allows at least partial recovery of the image if there are some hiccups.