Το βάθος πεδίου είναι μικρό.

In Greek, a full noun phrase used as the subject of a sentence usually takes an article. So το βάθος πεδίου is the normal way to say the depth of field as the subject.

English often leaves out the in technical expressions, but Greek is less likely to do that in an ordinary sentence. Without το, it could sound more like a heading, label, or very compressed technical style.

Because the article and adjective tell you:

• το = neuter singular
• μικρό = neuter singular

So βάθος is neuter.

This is a very useful lesson for Greek learners: a noun ending in -ος is not automatically masculine. Greek has nouns in -ος that can be masculine, feminine, or neuter.
For example:

• ο δρόμος = masculine
• η οδός = feminine
• το βάθος = neuter

So you should learn the noun together with its article.

Because Greek often uses the genitive case instead of a separate word like of.

Here:

• βάθος = depth
• πεδίου = of field

The base noun is πεδίο. Its genitive singular form is πεδίου.

So βάθος πεδίου literally works like depth of field, even though Greek does not insert a separate word for of.

The dictionary form is πεδίο.

In this sentence, it appears as πεδίου, which is the genitive singular form.

So the pattern is:

• το πεδίο = the field
• του πεδίου = of the field

And inside the phrase βάθος πεδίου, that genitive form shows the relationship depth of field.

Because adjectives in Greek must agree with the noun they describe in gender, number, and case.

The noun being described is βάθος, which is:

• neuter
• singular
• nominative

So the adjective must also be neuter singular nominative:

• μικρός = masculine
• μικρή = feminine
• μικρό = neuter

That is why the sentence says είναι μικρό.

είναι means is. It is the 3rd person singular form of είμαι (to be).

So the sentence structure is:

• Το βάθος πεδίου = the subject
• είναι = is
• μικρό = small

In normal Greek, you usually do not omit είναι in a sentence like this. If you left it out, it would sound incomplete or like a label rather than a normal statement.

The sentence as written has the most neutral, straightforward order:

Το βάθος πεδίου είναι μικρό.

Greek word order is more flexible than English, so other orders are possible for emphasis. For example:

• Μικρό είναι το βάθος πεδίου.

This puts extra focus on μικρό.

But for a basic, neutral statement, the original order is the best one to learn first.

Yes, μικρό literally means small or little.

In photography and optics, Greek commonly uses:

• μικρό βάθος πεδίου = shallow depth of field
• μεγάλο βάθος πεδίου = deep depth of field

So even if English often says shallow, Greek naturally says small here. This is a good example of why technical phrases should be learned as natural expressions, not only word by word.

A rough pronunciation is:

to VA-thos pe-THEE-ou EE-ne mi-KRO

A few notes:

• θ sounds like th in think
• δ sounds like th in this
• the written accents show the stressed syllable:
  • βάθος
  • πεδίου
  • είναι
  • μικρό

So πεδίου is stressed on the -δί- part, and μικρό is stressed on the last syllable.

It follows a very common Greek pattern:

[subject] + [form of είμαι] + [predicate adjective]

So here:

• Το βάθος πεδίου = subject noun phrase
• είναι = linking verb
• μικρό = predicate adjective

This is the same kind of structure as:

• Το σπίτι είναι μεγάλο. = The house is big.
• Το πρόβλημα είναι σοβαρό. = The problem is serious.

So the sentence is grammatically simple, even though βάθος πεδίου is a technical noun phrase.