Learn Hardcore Croatian: Na putovanju snimamo kratke filmove i radimo fotografije. - On the trip we record short films and take photographs.

na
- accusative = movement onto / to something
  - Idemo na putovanje. – We are going on a trip.
na
- locative = location or time on / during
  - Na putovanju snimamo… – On the trip / While on the trip we record…

Here, we are talking about what happens during the trip (a location in time/situation), so na takes the locative: na putovanju.

Could I say na putu instead of na putovanju? Do they mean the same thing?

They are close, but not identical:

na putovanju – on the trip / during the journey
Focuses on the entire trip as an event or period of time.
na putu – literally on the road / on the way
Often emphasizes the physical act of travelling or being en route from A to B.

In many contexts they overlap, but:

Na putovanju snimamo kratke filmove… – suggests “when we travel” or “while we’re on trips (in general)”.
Na putu snimamo kratke filmove… – sounds more like “while we are on the way (in transit) we record short films…”, a bit more literal, less like a “holiday/trip project”.

Both are possible, but na putovanju is more natural if you mean “on our trip/holiday” as an activity you do during that trip.

What is the infinitive of snimamo, and what does snimati mean exactly?

The infinitive is snimati.

Snimati means:

to record (video or audio)
to film, to shoot (movies, clips)
to take (x‑ray, medical imaging)

In this sentence, snimamo kratke filmove = “we record / shoot short films”.

So:

infinitive: snimati
1st person plural present: snimamo = “we record / we are recording”

What is the infinitive of radimo, and does raditi fotografije literally mean “to do photos”?

The infinitive is raditi.

Literally, raditi means “to do, to work, to make”. The phrase raditi fotografije is idiomatic Croatian and corresponds to English “to make / take photos”.

Some common ways to say “take photos”:

raditi fotografije – make/take photographs (quite neutral/formal)
slikati – to photograph, to take pictures
fotkati (colloquial) – to take photos, to snap pics
praviti fotografije – also possible, similar to raditi

In standard, neutral language, raditi fotografije or slikati are very common.

Why is it snimamo kratke filmove, not snimamo kratki filmovi?

Because of case and agreement:

The verb snimamo takes a direct object in the accusative case.
The noun film in plural accusative is filmove.
The adjective kratak must agree with filmove in gender, number, and case.

So we have:

nominative singular: kratak film
nominative plural: kratki filmovi
accusative plural: kratke filmove

Pattern:

masculine -i (nominative plural) → often -e (accusative plural)
adjective changes accordingly: kratki → kratke.

Since filmove is the direct object, it must be accusative, and the adjective follows it: kratke filmove.

Why does filmove end in -e in the plural, even though filmovi ends in -i?

For many masculine nouns in Croatian:

nominative plural ends in -i
accusative plural ends in -e

Example:

(NOM pl.) filmovi – films (subject)
(ACC pl.) filmove – films (direct object)

Other examples:

gradovi → gradove
zadaci → zadatke

In snimamo kratke filmove, filmove is the direct object, so it must be in the accusative plural, which takes -e.

What person and number are snimamo and radimo, and why is there no word for “we”?

Both snimamo and radimo are:

1st person plural, present tense → “we record”, “we make”.

In Croatian, personal pronouns (like mi = we) are usually omitted because the verb ending already shows the person and number:

snimam – I record
snimaš – you (sg.) record
snima – he/she/it records
snimamo – we record
snimate – you (pl./formal) record
snimaju – they record

So Snimamo kratke filmove already clearly means “We record short films”. Saying Mi snimamo kratke filmove is also correct, but it adds emphasis to mi (“WE record…”).

Can I change the word order, for example Na putovanju radimo fotografije i snimamo kratke filmove?

Yes, Croatian word order is quite flexible. All of these are grammatically correct:

Na putovanju snimamo kratke filmove i radimo fotografije.
Na putovanju radimo fotografije i snimamo kratke filmove.
Kratke filmove snimamo i radimo fotografije na putovanju.
Fotografije radimo i kratke filmove snimamo na putovanju.

Changes in word order mostly affect emphasis and what sounds most natural.

The original sentence first mentions film-making, then photos.
If you say Na putovanju radimo fotografije i snimamo kratke filmove, you’re slightly emphasizing that you (also) take photos, and then mention films.

For learners, it’s good to start with the original neutral order; later you can play with word order for nuance.

Why is it na putovanju and not u putovanju? How do I choose between na and u?

Both na and u can mean something like “in/on/at”, but they are used with different types of nouns and idioms.

With putovanje (trip, journey), the natural choice for “on a trip” is na:

na putu, na putovanju, na odmoru (on holiday), na sastanku (at a meeting)

U is more like “in(side)” something:

u kući – in the house
u gradu – in the city
u autu – in the car

So na putovanju is an idiomatic, fixed expression meaning “on a trip / while travelling”. U putovanju would sound very unnatural.

What aspect are snimamo and radimo? How would the sentence change with perfective verbs?

Both snimamo (from snimati) and radimo (from raditi) are imperfective verbs. Imperfective is used for:

ongoing actions
repeated actions
general habits

So the sentence describes what you (usually) do during a trip, or what you are in the process of doing.

Perfective counterparts:

snimiti – to (successfully) record/film (one or more complete acts)
napraviti / uraditi – to make/do (to completion)

Examples with perfective:

Na putovanju ćemo snimiti kratke filmove i napraviti fotografije.
“On the trip we will (manage to / succeed in) record short films and take photos.”
→ Focus on the result of the actions, not the ongoing process.

In your sentence, the imperfective form fits best because it describes what you do during the trip, not just the end result.

Why is there no word for “the” or “a” before kratke filmove and fotografije?

Croatian has no articles like English “a/an” or “the”. Definiteness and indefiniteness are usually understood from:

context
word order
sometimes pronouns or demonstratives (e.g. ti filmovi – those films, neki filmovi – some films)

So snimamo kratke filmove i radimo fotografije can mean:

“we make short films and take photos”
“we make the short films and take the photos”

Which one is meant depends on context. The grammar of the Croatian sentence itself does not force a/the.