01-05-2016, 01:46 AM
(This post was last modified: 01-06-2016, 12:10 AM by stargazer.
Edit Reason: clarity
)
The sun has a large apparent disc covering a big area. The lower limb has more atmospheric refractive bending than the upper limb. By the way, the bent light makes it look high, just like shooting at a fish with an arrow. With the lower limb appearing a bigger percentage higher than the upper limb, it makes the sun look flattened as it approaches the horizon.
So how have others been adjusting for the centerline of the apparent disc? Somewhere between the upper limb and lower limb tabulated amounts, but not exactly half way which would not allow for the increased effect on the lower limb?
Heck, I'm not even sure how to figure the halfway point, which would at least be fairly close to correct. I added the two corrections, one is a negative number so I got a smaller negative number. Appears sensible but seems awfully easy, so I fear it may be wrong.
Anyone have any ideas or good/bad experiences?
Edit: I should have mentioned that I'm using a reflective artificial horizon.
So how have others been adjusting for the centerline of the apparent disc? Somewhere between the upper limb and lower limb tabulated amounts, but not exactly half way which would not allow for the increased effect on the lower limb?
Heck, I'm not even sure how to figure the halfway point, which would at least be fairly close to correct. I added the two corrections, one is a negative number so I got a smaller negative number. Appears sensible but seems awfully easy, so I fear it may be wrong.
Anyone have any ideas or good/bad experiences?
Edit: I should have mentioned that I'm using a reflective artificial horizon.