@MichaelKjorling gives a good answer that should be expanded upon.
I'm guessing that you creature is an invertebrate since you mention it has "multiple tentacles" and imply that its 'head' is not a tradition head. It may be helpful to think about the evolutionary advantages for an animal with multiple methods of sight (and why we evolved sight in the first place). Why does an eagle need such great visual acuity? To see its prey from a great distance. Did you know birds can't turn their eyes? Its easiest to see where you're going with biological "blinders" built in. Why do fish have an eye on both sides of their head (yeah, yeah...except the flounder)? To see predators better. Did you know deep sea fish tend to see more blue/green while fish in lakes are rivers see more red? And sometimes you don't need any visual acuity at all. Sometimes you just need to know if something is between you and the light source, like an octopus that can sense light/dark with its skin. The eyes of dragonflies are linked directly to their wings to allow them to track prey without using any brain power. But in my opinion, the king-daddy of ocular evolution has to be the Mantis Shrimp. It has 12 different types of photo receptors (compared to our 3).
So thinking of your creature, perhaps it only has two "good" Mantis Shrimp-like eyes, but a multitude of other "eyes" that see varying degrees of detail or color. Its skin (which could sort of count as an eye) senses only light or dark so it knows when it is in hiding. Scattered around its body are numerous simple eyes that can sort of see. They're better than just sensing light/dark, but they lack a lens or mechanism for focusing so their main purpose is to grab the attention of better eyes when they detect something. The main eyes (2, 3, 5 whatever) would be like those of the Mantis Shrimp. These eyes would have numerous types of photoreceptors to see a broad spectrum of light as well as its polarization. Throw a couple on some retractable eye stalks since they will be the ones that use the most brain power and have the highest evolutionary cost (and therefore in need of the most protection), and you have a believable creature.
Edit: Expanding on the idea of brainpower and evolutionary costs.
Have you seen any of the YouTube videos where kids flip a bottle of water and get it to land correctly (yeah, I don't get it either :/ )? What you don't see is the huge number of failed attempts they make before finally getting it. Nature does the same. There isn't any intelligence involved in evolution. Evolution is a series of mutations. Some mutations help the organism survive, and some don't. This is natural selection at work. "Oh, that extra rib prevented you from jumping out of the way and didn't stop the hawk from eating you once he caught you? Good thing it took those genes out of the gene pool."
The evolution of vision really exploded during the Cambrian period. Not coincidentally, body coloration (as camouflage, as a warning that "Hey, I'm poisonous!", or as a reproduction method "Hey, look at me! I'm sexy!") also exploded during that time. But this came at a cost. Senses take energy. A study of blind Mexican cave fish found that they use 5 to 15% less of their metabolism by not having sight. And why have a circadian rhythm when there's no day/night cycle? That's another big energy savings. Want to eat on cold days? That will cost ~50% of your metabolic energy. Chimps have something like twice as many glucose transporters in their muscles than we do which is why they are pound for pound stronger than a human (sorry, I can't find a link to back that up...just pulling it from a memory of an article I hope was factual). Somewhere on our evolutionary path, we "transferred" some of our glucose transporters from our muscles to our brains. Our ability to "out smart" other animals costs us about 20% of our caloric intake. Every biological activity has a cost.
If you want to have lots and lots of biological activity (eg, multiple eyes, mouths, limbs, etc.), you either need to eat A LOT, find energy dense food, or cut energy consumption in other areas. This known as the Expensive Tissue Hypothesis. In a nutshell, the greater the evolutionary cost, the more energy it consumes. And if it consumes a lot of energy, it must be pretty vital to the survival of the organism. If it isn't vital to the survival of the animal, it will eventually go away. Things that are vital for survival get protected: vital organs have a rib cage, the brain has a skull, eyes have lashes or eyelids or nictitating membranes, etc.
And finally coming back around to your creature. The simple light/dark sense of the skin doesn't require much on the order of brain power or metabolic energy (at least, I'm presuming it doesn't since this is the earliest "eye" in evolutionary terms). The simple eyes that can make out vague shapes can be wired directly to the mantis-eye stalks (thereby saving brain power) so that when they see "something", the eye stalks automatically swivel to gather details. This isn't very far fetched. Horseshoe crabs have two simple eyes on their belly so they can see predators above them when they are swimming (because they swim upside down). In terms of your creature, I'm imaging a species of octopi that figures out how to cook food over thermal vents which in turns leads to even larger brains.
