Learn Hardcore Portuguese (Portugal): Ontem fotografámos a escultura com a minha nova câmara. - Yesterday we photographed the sculpture with my new camera.

Because this is the first-person plural of the pretérito perfeito (simple past) for an –ar verb, and the acute accent marks the stressed á. It also distinguishes fotografámos (we photographed) from the present tense fotografamos (we photograph).

Why do we use the pretérito perfeito here instead of the present or a compound tense?

Because ontem (yesterday) indicates a completed action at a specific time. In European Portuguese, you normally use the pretérito perfeito to say “we did X yesterday,” rather than a compound like temos fotografado.

Why is a used before escultura? Is that the personal “a”?

No, this a is just the feminine singular definite article (“the”). It’s not the personal a, which only appears before people or personified beings. Here you’re referring to a specific sculpture, so it needs a escultura.

Why do we say com a minha nova câmara? Could we use another preposition?

We use com to express the means or instrument (“with my camera”). It’s the most natural way. You could say usando a minha nova câmara (“using my new camera”), but com is shorter and more common.

Why is it minha and not meu, and do we always include the article before a possessive?

Possessive adjectives agree in gender and number with the noun: câmara is feminine, so it’s minha. In European Portuguese you almost always keep the definite article (a minha) before a possessive, whereas in English you’d just say “my.”

Can we place ontem somewhere else in the sentence?

Yes. Ontem is an adverb of time, so you can put it at the beginning (Ontem fotografámos…), after the verb (Fotografámos ontem…) or even at the end (Fotografámos a escultura com a minha nova câmara ontem.). Starting the sentence with it is most common for emphasis.

Could we use a different verb instead of fotografar, for example tirar fotos?

Absolutely. A more colloquial alternative is tirar fotos (to take photos):
“Ontem tirámos fotos à escultura com a minha nova câmara.”
Both convey the same meaning.

Does câmara always mean “camera”? I’ve also seen câmara meaning “council.”

Câmara can mean “chamber,” “city council” (e.g. Câmara Municipal) or “camera.” When you want to be extra clear you say câmara fotográfica. In context, photographers will understand câmara as the camera.