eizou wo mimasita.

を marks 映像 as the direct object of the verb. In other words, it shows that the video/footage is the thing being watched.

So:

• 映像 = video footage / images / visual material
• を = object marker
• 見ました = watched / saw

A very literal breakdown is:

• 映像を見ました
• (I) watched the footage

Japanese often leaves out the subject, so I is understood from context.

This is a very common beginner question.

The particle を is traditionally romanized as wo, but in modern Japanese it is usually pronounced simply as o.

So:

• written: を
• romanized: wo
• actual pronunciation in a sentence: basically o

So 映像を見ました sounds like:

• eizō o mimashita

not eizō wo mimashita in normal speech.

映像 is pronounced eizō.

A simple breakdown:

• えい = ei
• ぞう = zō

Important point: the おう / ō part is a long o sound.

So it is closer to:

• ei-zoh

not a short zo.

The dictionary form is 見る.

Here is the relationship:

• 見る = to see / to watch
• 見ます = see/watch (polite non-past)
• 見ました = saw/watched (polite past)

So 見ました is the polite past form of 見る.

It can mean either saw or watched, depending on context.

The verb 見る is broader than the English verb watch. It can be used for:

• seeing something
• watching something
• looking at something

With 映像, English often translates it as watched the footage/video or saw the footage/video.

So both can be natural, depending on the situation.

It is polite because of 見ました.

The ます form is the standard polite style used in:

• normal conversation with strangers
• class
• work
• polite everyday speech

Compare:

• 映像を見ました。 = polite
• 映像を見た。 = casual

Both mean basically the same thing, but the tone is different.

Japanese very often omits the subject when it is clear from context.

So 映像を見ました。 could mean:

• I watched the footage
• We watched the footage
• He/She watched the footage

depending on the situation.

In English, you usually need a subject. In Japanese, you often do not.

If you wanted to include it, you could say something like:

• 私は映像を見ました。 = I watched the footage.

But if I is already obvious, Japanese usually leaves it out.

Not exactly.

映像 usually means visual images, video footage, or visual material. It is a fairly broad word.

Compare:

• 映像 = footage, video images, visual material
• 映画 = movie, film
• 動画 = online video / moving image clip
• ビデオ = video

So 映像を見ました often sounds like:

• watched some footage
• viewed some video material
• saw the images/video

It does not automatically mean a full movie.

No, normal Japanese is usually written without spaces.

The standard writing is:

• 映像を見ました。

Spaces are often added in textbooks or beginner materials to make the parts of the sentence easier to see.

So the spaced version is just a learning aid.

In casual spoken Japanese, particles are sometimes dropped, so you may hear something like:

• 映像見た
• 映像見ました

However, for learners, it is best to keep を in normal sentences:

• 映像を見ました。

That is the standard and safest form.

So:

• with を = grammatically complete and standard
• without を = possible in casual speech, but less formal and not the best default for beginners