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The “Modern Eddington Experiment”: Spontaneous Emissions
And now for something completely different.
Sometimes, when I try to describe to others what I do as a color scientist, I am asked if I can fix their photos. Usually it is to make their printer look more like their monitor, but a few years ago it was a friend asking about how to correct his underwater pictures while scuba […]
Eddington epilogue
I was lucky to have ended up at this observing location with such excellent weather. When planning to view total eclipses, I am advised to arrange for other activities as well; the eclipse itself is subject to fickle viewing conditions (my one prior total solar eclipse effort was thwarted, but the travel experience was rewarding […]
Discussion
It is a bit disappointing to be unable to show a clear gravitational signal, even with all of the successful exposures that were taken, but I recognized the difficulty of this measurement early on. In addition to the variables I anticipated, there are some additional uncertainties that I now recognize. Here is my updated list […]
Analyzing Eclipse Day Results
I was able to obtain 35 photos during totality that were candidates to locate stars in the field. The exposures ranged from 1/60 to 2 seconds, but it became clear after applying the detection procedure starPos.m, that only the longest exposures, 1 and 2 seconds, would yield detected stars. The inner regions of the corona […]
Comparing Before and During images, step EE-4
This was written prior to eclipse day as I was contemplating how to compare the two image sets. I include it here to keep the thought sequence intact. When we apply steps EE-1, 2, and 3 to both the before images and the during images, we will have a set of radial distances to […]
Category Archives: Uncategorized
And now for something completely different.
Sometimes, when I try to describe to others what I do as a color scientist, I am asked if I can fix their photos. Usually it is to make their printer look more like their monitor, but a few years … Continue reading
Eddington epilogue
I was lucky to have ended up at this observing location with such excellent weather. When planning to view total eclipses, I am advised to arrange for other activities as well; the eclipse itself is subject to fickle viewing conditions … Continue reading
Discussion
It is a bit disappointing to be unable to show a clear gravitational signal, even with all of the successful exposures that were taken, but I recognized the difficulty of this measurement early on. In addition to the variables I … Continue reading
Analyzing Eclipse Day Results
I was able to obtain 35 photos during totality that were candidates to locate stars in the field. The exposures ranged from 1/60 to 2 seconds, but it became clear after applying the detection procedure starPos.m, that only the longest … Continue reading
Comparing Before and During images, step EE-4
This was written prior to eclipse day as I was contemplating how to compare the two image sets. I include it here to keep the thought sequence intact. When we apply steps EE-1, 2, and 3 to both the … Continue reading
Corona tangent
I encountered a report about the predicted corona and wondered how it would compare to what we actually saw. I do not know the orientation of either the simulation or of my image (where is the solar north pole?). Are these … Continue reading
Eclipse Day!
The good weather held and we had zero clouds and negligible smoke for the eclipse. Temperatures were climbing in the bright morning sun, but stalled and then dropped during the partial phases of the eclipse– enough that we donned our … Continue reading
Step EE-3: Finding the best fit
We now have a way to transform the stars detected in an image into our virtual camera reference frame, but the previous step was just the “rough alignment” based on two bright stars. This is vulnerable to errors in how … Continue reading
Step EE-2A: A side process to calibrate (radial) lens distortion
Unexpected errors while looking for the best angular fit between the imaged stars and their reference locations. My early efforts to map the imaged stars onto their virtual camera positions showed unexpected errors. They were close, but displayed error … Continue reading
Step EE-2: Transform to reference coordinates
The field of view for my EOS60Da APSC sensor (inner rectangle) and the EOS6D full-frame sensor (middle rectangle). The map overlay is the view from Idaho Falls on the day of the eclipse as displayed by Stellarium (and inverted to … Continue reading