NavList:

In addition to safety, there is also the consideration of comfort. I recently had a conversation with someone over on the cruisers forum who said that he found it uncomfortable to look at the sun in an artificial horizon through the shades of his Davis Mk.15. I thought that was odd, considering I'd never had a problem, and I told him that. He posted a video of what he was seeing, and it did appear much brighter than what I was used to. Several people (including myself) suggested he might have gotten a defective instrument. (There was also a problem with the micrometer knob coming loose.)

Anyway, he wrote to Celestaire and they promptly supplied him with a replacement ... but he still had the same shade problem. (The micrometer knob was much better.) Now, I could understand one dud sextant slipping past Davis' and Celestaire's quality control - but two ... going to the same person? Extremely unlikely, IMHO. In the end he found that, if he kept the image of the sun on the unsilvered half of the horizon glass, he could comfortably take sights. I can only suppose that his eyes are more sensitive than the average person's.

He did toy around with the ideas of swapping out shades or adding some solar film somewhere in the light path to dim the image even more, but I don't know if he ever followed through with that. Point is: everyone is different and you might also find that the brightness is too much for your comfort level. If so, you can try either of the two solutions above - or some other remedy, such as Ed's suggestion. Note also that, in addition to clear glass, the Davis artifical horizon comes with two plastic windscreens which are tinted orange and blue - the same as some of the shades on their sextants. When used together they dim the reflected image of the sun quite a lot. So much so that I don't have to use any horizon shades at all when I have both of the plastic windscreens in place.

Cheers,

Sean