Une résolution d’image élevée utilise plus d’espace de stockage.

Because résolution is a feminine singular noun in French, so it takes the feminine singular indefinite article une.

• une résolution = a resolution
• Compare:
  • un fichier = a file (masculine)
  • une image = an image (feminine)

So une résolution is grammatically required here.

French usually shortens de to d’ before a vowel sound. This is called elision.

• de + image → d’image
• de + espace → d’espace

So:

• résolution d’image
• espace de stockage
• plus d’espace

This is very common in French and helps the language flow more smoothly.

Élevée is an adjective meaning high or elevated here. It describes résolution.

So:

• une résolution élevée = a high resolution

Because résolution is feminine singular, the adjective must also be feminine singular:

• masculine singular: élevé
• feminine singular: élevée

This is adjective agreement.

Because the noun it describes, résolution, is feminine singular.

French adjectives usually change form to match the noun they describe:

• un niveau élevé = a high level
• une résolution élevée = a high resolution

The extra -e marks the feminine form.

In French, many adjectives come after the noun, and élevé/élevée usually does in this kind of technical meaning.

So French says:

• une résolution élevée

where English says:

• a high resolution

This difference in word order is very normal in French.

Yes, but the phrasing is slightly different.

Very common French expressions are:

• une image haute résolution
• une image en haute résolution
• la haute résolution

In your sentence, une résolution d’image élevée is grammatically correct and understandable, but many native speakers would more naturally say something like:

• Une image en haute résolution utilise plus d’espace de stockage.
• Une image à haute résolution utilise plus d’espace de stockage.

So élevée works, but haute résolution is also a very common set phrase.

Because the subject is une résolution d’image élevée, which is grammatically singular.

The main noun of the subject is résolution, not image. So the verb agrees with résolution:

• Une résolution ... utilise = singular
• Des résolutions ... utilisent = plural

Even though image appears in the phrase, it is inside résolution d’image and is not the main subject.

After expressions of quantity like plus de, French normally uses de/d’ without an article.

So:

• plus d’espace = more space
• not plus de l’espace

This is because espace here is being used as an uncountable idea, like space/storage capacity, not a specific piece of space.

Other examples:

• plus d’eau = more water
• plus de temps = more time
• plus de mémoire = more memory

De stockage means for storage or of storage.

• espace = space
• stockage = storage

So:

• espace de stockage = storage space

This is a very common French pattern:

• une salle de bain = bathroom
• une carte de crédit = credit card
• un espace de stockage = storage space

The structure is often noun + de + noun.

Because espace de stockage is a general category: storage space.

French uses de without an article when one noun describes the type or function of another noun.

• espace de stockage = storage space
• bouteille d’eau = water bottle
• table de cuisine = kitchen table

If you said du stockage, it would sound more like space of the storage or space belonging to the storage, which is not the intended meaning here.

Not exactly.

• résolution d’image = image resolution in a general or technical sense
• résolution de l’image = the resolution of the image, referring to one specific image

So in your sentence, résolution d’image sounds more general and fits a general statement better.

Compare:

• La résolution d’image est importante. = Image resolution is important.
• La résolution de l’image est faible. = The resolution of the image is low.

Here, plus means more.

So:

• plus d’espace de stockage = more storage space

It is not the negative ne ... plus meaning no longer.

Compare:

• Cette image utilise plus d’espace. = This image uses more space.
• Cette image n’utilise plus d’espace. = This image no longer uses space.

So the meaning of plus depends on context.

It would become:

• Des résolutions d’image élevées utilisent plus d’espace de stockage.

Changes:

• une → des
• résolution → résolutions
• élevée → élevées
• utilise → utilisent

This shows both noun-adjective agreement and subject-verb agreement.

Utilise is the third-person singular form of utiliser, meaning to use.

Here it means:

• uses

So:

• Une résolution d’image élevée utilise... = A high image resolution uses...

French often uses utiliser in technical contexts the same way English uses use.

Examples:

• Ce logiciel utilise beaucoup de mémoire. = This software uses a lot of memory.
• Cette vidéo utilise plus de bande passante. = This video uses more bandwidth.

Yes. Résolution has several meanings depending on context, just like resolution in English.

It can mean:

• image/screen resolution
• a decision or formal resolution
• determination or resolve in some contexts

In this sentence, because of d’image, it clearly means image resolution.

So d’image is important because it removes ambiguity.

Yes, it is grammatical and clear. However, in everyday technical French, many speakers would more naturally phrase it as:

• Une image en haute résolution utilise plus d’espace de stockage.
• Une image à haute résolution utilise plus d’espace de stockage.

Your original sentence is still correct, but it focuses more directly on the resolution itself rather than on the image.

So it is a good sentence for learning grammar, especially:

• article agreement
• adjective agreement
• de/d’ elision
• quantity with plus de
• noun phrases like espace de stockage