Why is one of my dog's eyes metallic and reflective? Is it an issue?

This is normal in dogs! It's a part of their anatomy (also in cats and other similar species) called the tapetum lucidum. This is what gives dogs that glowy, reflective look and a "red eye" when looking into a camera or light at night. Here's an article on the structure of the eye that you're seeing: https://www.acvo.org/tips-treatments-tricks/why-do-my-dogs-eyes-shine-at-night

Hello, that reflection in your dogs eyes appears like norma tapetal reflection. Red eyes do not always indicate blindness, so I wouldn't create that association with your dog's eyes. More so, look for any signs to bumping into things, being startled, looking into space and being unable to find his food bowl. These would be more likely to be consistent with blindness. Hope this helps and best of luck.

What you're seeing is likely the small blood vessels of the eye and pigmentation of the cornea. This is typically very normal, but if you are concerned you should take Dunbar to the vet for an ocular exam.

It is difficult to say without a picture, if not an eye exam. Tapetal reflection can be seen during daylight depending on where you and Tomita are in relation to a light source. If this is the case, the eye could be normal. If the shining is in the anterior chamber, this could be uveitis, a problem with the iris, a lipid Deposit, or other. The fact that the eye is visual and comfortable is a great sign but a good eye exam (with a veterinary ophthalmologist if it is very unusual) is a good idea.

I can see that the sclera (white part of the eye) does look a little red in your last picture. This could be from trauma but can also be seen with conjunctivitis or even a corneal ulcer. Given Mitzer's breed I would recommend seeing a vet to make sure the cornea does not appear affected. They can also look at the lens and the back of the eye to make sure there is nothing abnormal that would cause a difference in the reflection from the back of the eye.

When you take photos of your pets or people and the flash hits the eyes at a certain angle you will be able to see through the pupils to the back of the lense which has a lot of blood vessels. This will appear red and is normal. This will often happen when you take pictures of people also. Here you have some information: http://www.yalescientific.org/2011/05/what-causes-the-red-eye-effect/

This could be just a normal pigment change or it could be something more serious. I would have your vet take a look to ensure there is no infection or other abnormalities with the eye. i hope this helps!