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Sighting the eclipse - BigBill - 08-21-2017

I'm thinking I might try and take a sextant sighting of the sun (and moon) during the eclipse. It could be interesting.
I hope the clouds stay out of the way.


RE: Sighting the eclipse - CelNav57 - 08-21-2017

We just had very good success looking at the eclipse using the sextant and also allowing the unfiltered sun light to be projected through the telescope on to a piece of white paper. Focus the sun's image on the paper and you'll get a good sharp image. The greater the distance between the telescope and the paper target- the larger the image. That is the best method so far.

CelNav57


RE: Sighting the eclipse - BigBill - 08-21-2017

I was able to see it well.

I wonder if the eclipse bends the light somewhat. I took a number of sun sights during the event but so far have only reduced two of them. They are both off by 20+ miles. It'll be interesting to see if they are all off and consistent.


RE: Sighting the eclipse - c_davidson - 08-21-2017

(08-21-2017, 09:22 PM)BigBill Wrote: I was able to see it well.

I wonder if the eclipse bends the light somewhat. I took a number of sun sights during the event but so far have only reduced two of them. They are both off by 20+ miles. It'll be interesting to see if they are all off and consistent.

Curious isn't it?  Do you think because you were only observing a portion of the Sun (assuming not the Upper Limb) and not complete Lower Limb that the difference in Hs is the cause?

It was a fantastic eclipse and I'm quite pleased to know that a sextant is so helpful in viewing the Sun.

Clen


RE: Sighting the eclipse - BigBill - 08-22-2017

(08-21-2017, 10:45 PM)c_davidson Wrote:
(08-21-2017, 09:22 PM)BigBill Wrote: I was able to see it well.

I wonder if the eclipse bends the light somewhat. I took a number of sun sights during the event but so far have only reduced two of them. They are both off by 20+ miles. It'll be interesting to see if they are all off and consistent.

Curious isn't it?  Do you think because you were only observing a portion of the Sun (assuming not the Upper Limb) and not complete Lower Limb that the difference in Hs is the cause?

It was a fantastic eclipse and I'm quite pleased to know that a sextant is so helpful in viewing the Sun.

Clen

It's still too early to tell, maybe I just messed up my sights. I was making a video and scrambling to write down the times and read off the vernier and bumping into things in 85 degree temps. I should probably do an internet search to see if there are considerations for taking a sight during an eclipse that I'm not aware of. Maybe there's a standard deviation to factor in.

  From what I could make out, the entire sun should have been within the bubble (bubble sextant) and though only the shadow from the moon was visible, the entire moon should have been within the bubble as well. I haven't tried to reduce the moon sights yet but if they are also off, it will be interesting to see if they have the same error as the sun sights.