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Post by marklemon on Nov 20, 2007 10:37:00 GMT -5
I am trying to accurately reconstruct how much, if any, ambient light existed during the hour to hour and a half that transpired during the battle in 1836. Has anyone done any serious research on this subject, i.e. calculating, by factoring in our current daylight saving time, what would be the CURRENT, Central Standard Time window of time that most accurately duplicates the same period from 1836?
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Post by TRK on Nov 20, 2007 11:13:38 GMT -5
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Post by marklemon on Nov 20, 2007 11:54:28 GMT -5
Tom, Thank you sir, that was very helpful, especially wolfpack's initial post. Mark
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Post by TRK on Nov 20, 2007 12:43:18 GMT -5
Glad to help, Mark.
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Post by Herb on Nov 20, 2007 15:07:57 GMT -5
Mark,
I remain convinced that the bulk of the fighting occurred between 6 and 7 AM CST for the reasons cited in the above link.
But, there is one very significant problem that I don't know how to address and that is cloud cover. If you accept DLP, he mentions cloud cover, but imo the translation by Carmen Perry is contradictory in that he speaks of the moon providing light to see as they deployed, but that it was "opaque" and prevented the defenders from detecting the deployment.
I wish somebody like Tom could try to translate that passage and make more sense out of it! The best meaning I can make out of it is that there was enough cloud cover to limit the range of visibility from a nearly full moon, but not too much to hinder movement.
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Post by TRK on Nov 20, 2007 15:18:41 GMT -5
I wish somebody like Tom could try to translate that passage and make more sense out of it! You secure a copy of the page(s), and I'll be glad to translate it
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Post by marklemon on Nov 20, 2007 15:21:33 GMT -5
wolfpack So, as I understand you, the present amount of daylight that occurs TODAY, between 6 and 7 AM, closely corresponds to the 1836 battle timeframe of 5 to 6, or 6:30?. As I recall, during the dawn ceremonies, by the time 7AM comes around, there is no actual sunlight, but rather that grayish, pre-dawn light that permeates the scene. That is the light condition that I was imagining, but wanted to be sure. Mark
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Post by Herb on Nov 20, 2007 15:43:09 GMT -5
wolfpack So, as I understand you, the present amount of daylight that occurs TODAY, between 6 and 7 AM, closely corresponds to the 1836 battle timeframe of 5 to 6, or 6:30?. As I recall, during the dawn ceremonies, by the time 7AM comes around, there is no actual sunlight, but rather that grayish, pre-dawn light that permeates the scene. That is the light condition that I was imagining, but wanted to be sure. Mark Exactly. With the nearly full moon - none of the battle was really in the dark (with the possible exception of the impact of cloud cover). The effect of shadows, however would have been significant. I mentioned the effect of the defenders being skylighted and shooting down into shadows in the above link. But for the Mexicans once in the compound, they would have been in the light attacking into shadows as they attacked the Long Barracks and the Church. The light conditions also significantly effected the Cavalry action, imo. With what sun there was - on the eastern horizon, at the cavalry's back, would have made the cavalry virtually undetectable while illuminating the defenders as they moved from the west.
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Post by Herb on Nov 20, 2007 16:01:23 GMT -5
I wish somebody like Tom could try to translate that passage and make more sense out of it! You secure a copy of the page(s), and I'll be glad to translate it If I knew how to get a copy of the original Spanish, it would already be in your hands!
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Post by TRK on Nov 20, 2007 16:09:07 GMT -5
The Center for American History, UT Austin, has the DLP manuscript; I'd guess there are restrictions on photocopying them.
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Post by stuart on Nov 20, 2007 16:22:44 GMT -5
Its perhaps worth making the point (as I'm sure Bill will agree) that there is a very significant amount of light generated by gunpowder artillery and small arms fire - far more than from modern smaller calibre weapons with smokeless powder and flash suppressers.
To use a rather old fashioned expression the Alamo inside and out will have been lit up like a Brock's benefit once the action got going.
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Post by billchemerka on Nov 20, 2007 20:18:08 GMT -5
Its perhaps worth making the point (as I'm sure Bill will agree) that there is a very significant amount of light generated by gunpowder artillery and small arms fire - far more than from modern smaller calibre weapons with smokeless powder and flash suppressers. To use a rather old fashioned expression the Alamo inside and out will have been lit up like a Brock's benefit once the action got going. But the illuminations are erratic and cause optical exaggerations thereby negating the constant light necessary to maintain visual continuity. I recall participating in a dawn Battle of Cedar Creek reenactment years ago in Virginia in which the musket volleys shrouded individuals on the battle field rather than highlighted them. And a Rev. War artillery demonstration back in 1981 at night was more blinding than illuminating. These visual variables are difficult to compartmentalize. As such, they make assumptions that are difficult to support with metaphysical certainty.
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Post by Allen Wiener on Nov 20, 2007 23:45:38 GMT -5
The Center for American History, UT Austin, has the DLP manuscript; I'd guess there are restrictions on photocopying them. Take a look at this link. I don't think it offers much of the document in Spanish, but there are some contact names and emails at the bottom. www.cah.utexas.edu/exhibits/Pena/pena.htmlAW
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Post by stuart on Nov 21, 2007 9:44:59 GMT -5
Its perhaps worth making the point (as I'm sure Bill will agree) that there is a very significant amount of light generated by gunpowder artillery and small arms fire - far more than from modern smaller calibre weapons with smokeless powder and flash suppressers. To use a rather old fashioned expression the Alamo inside and out will have been lit up like a Brock's benefit once the action got going. But the illuminations are erratic and cause optical exaggerations thereby negating the constant light necessary to maintain visual continuity. I recall participating in a dawn Battle of Cedar Creek reenactment years ago in Virginia in which the musket volleys shrouded individuals on the battle field rather than highlighted them. And a Rev. War artillery demonstration back in 1981 at night was more blinding than illuminating. These visual variables are difficult to compartmentalize. As such, they make assumptions that are difficult to support with metaphysical certainty. Absolutely right Bill. The point I'm making is that chasing after the levels of natural ambient light is probably the wrong hare. Against the question of whether or not the moon was peeking behind the clouds you have to set the very dramatic pyrotechnics which will have destroyed the the chiaroscuro of those flashes (and bangs) the level of natural light or lack of it becomes pretty irrelevant
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Post by Herb on Nov 21, 2007 13:22:16 GMT -5
Absolutely right Bill. The point I'm making is that chasing after the levels of natural ambient light is probably the wrong hare. Against the question of whether or not the moon was peeking behind the clouds you have to set the very dramatic pyrotechnics which will have destroyed the the chiaroscuro of those flashes (and bangs) the level of natural light or lack of it becomes pretty irrelevant I'll have to disagree with you there. I won't deny the effect of muzzle or pan flash, but the available natural light was a critical component in the battle - for both sides. Target detection, march orientation all were impacted before there ever was a muzzle flash. Besides there are two other factors the first and formost is that the majority of the battle took place in morning twilight - when muzzle flash was irrelevant (powder smoke is another story). The other factor is that even before the twilight period, most people familiar with weapons know to close one eye before firing to preserve at least a portion of your night vision. Flashes at a distance have significantly less impact on night vision than those close up.
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