Eksponeringen på lysmåleren er riktig.

Because -en is the usual definite singular ending in Bokmål for many nouns.

• eksponering = exposure
• eksponeringen = the exposure
• lysmåler = light meter
• lysmåleren = the light meter

So Norwegian often puts the idea of the at the end of the noun instead of using a separate word before it.

In Norwegian, the definite article is usually attached to the noun as a suffix.

So instead of:

• the exposure
• the light meter

you get:

• eksponeringen
• lysmåleren

A separate article is often added only when there is an adjective before the noun. For example:

• den riktige eksponeringen = the correct exposure

That pattern is often called double definiteness.

Here på lysmåleren means something like on the light meter or on the meter/display.

Norwegian often uses på for things shown, located, or read on a device, screen, display, or instrument. So if a value appears on a meter, på is very natural.

Using i would suggest something more like inside the light meter, which is usually not the meaning here.

Yes. Norwegian very often forms compound nouns by writing them as one word.

• lys = light
• måler = meter / measurer
• lysmåler = light meter

This is very common in Norwegian, much more so than in English. So where English might write two words, Norwegian often writes one.

Because riktig is a predicate adjective here, and it agrees with a singular noun.

The subject is eksponeringen, which is singular, so the adjective stays in its basic singular form:

• Eksponeringen er riktig. = The exposure is correct.

If the subject were plural, you would normally use riktige:

• Eksponeringene er riktige. = The exposures are correct.

Er is the present tense of å være, which means to be.

So:

• å være = to be
• er = is / are / am depending on context

In this sentence, er means is:

• Eksponeringen ... er riktig. = The exposure ... is correct.

The structure is:

subject + verb + adjective/complement

So:

• Eksponeringen på lysmåleren = subject
• er = verb
• riktig = complement/predicate adjective

That is the normal word order in a simple Norwegian statement, just like in English:

• The exposure on the light meter is correct.

Usually yes in a sentence like this. Riktig often means correct, right, or accurate, depending on context.

Here it means that the exposure reading is the right one.

A word like korrekt also exists, but riktig is often the more natural everyday choice. In technical contexts, both can appear, but riktig is very common and idiomatic.

In some varieties of Bokmål, yes, that may be possible.

Many nouns can appear with either:

• -en definite ending
• or -a definite ending

depending on gender choice and writing style. So some speakers/writers may use eksponeringa.

However, eksponeringen is completely normal and is a very standard form in Bokmål. If this is the form you are learning first, it is a safe choice.

In practice, it usually refers to the exposure value/setting/reading associated with the light meter.

That is why på lysmåleren matters: it narrows the meaning to the exposure as shown or indicated on that device, not just exposure in an abstract sense.

So even if the English meaning is already clear to you, the Norwegian wording strongly suggests the exposure reading on the light meter is correct rather than just exposure is correct in a general sense.