A técnica ficou de editar o vídeo da apresentação, mas eu preferi gravar de novo com a câmera do celular.

In this sentence, a técnica means the female technician.

Portuguese allows técnica to mean two different things:

• técnica = technique, method
• técnica = female technician / female specialist

Here, the context makes it clear it is a person, because ficou de editar o vídeo describes something someone agreed or was supposed to do.

Related forms:

• o técnico = male technician
• a técnica = female technician
• a técnica = the technique

So this is one of those cases where context tells you which meaning is intended.

Ficar de + infinitive is a very common Portuguese structure. It usually means:

• to agree to do something later
• to be supposed to do something
• to leave it arranged that someone will do something

So a técnica ficou de editar o vídeo does not literally mean the technician stayed to edit the video.

It means something more like:

• she agreed to edit it
• she was going to edit it
• it was her responsibility to edit it

This structure often suggests an arrangement or expectation, not necessarily that the action was completed.

Examples:

• Ele ficou de me ligar. = He said he would call me.
• Nós ficamos de conversar depois. = We agreed to talk later.

Because ficar de + infinitive is its own expression, and here it is being used in the preterite: ficou.

That gives the idea of a past arrangement that was made:

• ficou de editar = she agreed / was supposed to edit

If you used estava, the meaning would be different:

• estava editando = was editing
• ia editar = was going to edit

So ficou de editar is not about the editing itself happening. It is about the plan or commitment.

No, not necessarily.

That is a very important nuance. Ficou de editar only tells you there was an agreement, intention, or expectation. It does not confirm the action happened.

If you wanted to say she actually did it, you would say something like:

• A técnica editou o vídeo. = The technician edited the video.

In your sentence, the second part — mas eu preferi gravar de novo — strongly suggests the speaker chose another solution instead.

Da apresentação describes what kind of video it is:

• o vídeo da apresentação = the presentation video / the video of the presentation

Portuguese often uses de where English uses noun-noun combinations.

Compare:

• o carro do professor = the teacher’s car
• a porta da sala = the classroom door
• o vídeo da apresentação = the presentation video

So da here is simply connecting vídeo and apresentação.

They are contractions:

• da = de + a
• do = de + o

In the sentence:

• o vídeo da apresentação = the video of the presentation
• a câmera do celular = the camera of the cellphone

These contractions are extremely common in Portuguese and happen automatically when de comes before a definite article.

Other common ones:

• de + as = das
• de + os = dos

Because preferir is normally followed directly by an infinitive.

So:

• preferi gravar = I preferred to record
• prefiro sair cedo = I prefer to leave early

You do not use de after preferir in this structure.

Another common pattern is:

• preferir X a Y = to prefer X to Y

For example:

• Prefiro café a chá. = I prefer coffee to tea.

But in your sentence, preferi gravar is the normal structure.

Yes, it could be omitted.

Portuguese often drops subject pronouns when the verb already makes the subject clear:

• mas preferi gravar de novo = also correct

Here, eu is included for contrast:

• the technician was supposed to edit it, but I preferred to record it again

So eu adds emphasis, especially after mas.

No. Gravar can mean to record in general, including:

• audio
• video
• music
• voice messages
• TV programs

In this sentence, because it mentions a câmera do celular, gravar clearly means recording video.

Useful comparison:

• gravar = to record
• filmar = to film

Both can work in video contexts, but gravar is very common in everyday Brazilian Portuguese.

Here, de novo means again.

So gravar de novo means:

• record again
• re-record

Yes, it is often similar to novamente, but de novo is more common and conversational in everyday Brazilian Portuguese.

Compare:

• Vou tentar de novo. = I’ll try again.
• Vou tentar novamente. = I’ll try again.

In this sentence, de novo can also suggest doing it over from the beginning, which fits the idea of re-recording.

Because the sentence is emphasizing the instrument used.

• com a câmera do celular = with the cellphone camera

This focuses on the fact that the speaker used the phone’s camera as the tool.

If you said:

• gravei no celular

that usually means something more like:

• I recorded it on my phone

That can emphasize the device itself, rather than specifically the camera.

So com a câmera do celular is a little more precise.

Yes. In Brazilian Portuguese, celular is the normal everyday word for cell phone / mobile phone.

So:

• câmera do celular = cellphone camera / phone camera

In European Portuguese, you are more likely to hear telemóvel, but in Brazil celular is standard.

Yes, absolutely.

That is one of the most natural implications of de novo here. It suggests there was already a first version, and the speaker chose to make a new one.

So the sequence is likely something like:

1. there was a presentation video
2. the technician was supposed to edit it
3. instead, the speaker decided to record it again with a phone camera

That is why gravar de novo feels very natural in this context.