July Solar Challenge
- Montana
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July Solar Challenge
Dust off your January perihelion images from around 4th January (doesn't have to be exact!) and check what equipment you used to get a full solar disc.
Now image the full solar disc with the same equipment around aphelion day on the 4th July.
Post your images here, let's see some amazing imaginative presentations to show the solar size differences
If you forgot to take an image in January, don't worry, the next perihelion is just 6 months away on 4th January 2023, so get snapping away
https://www.timeanddate.com/astronomy/p ... stice.html
Alexandra
Now image the full solar disc with the same equipment around aphelion day on the 4th July.
Post your images here, let's see some amazing imaginative presentations to show the solar size differences
If you forgot to take an image in January, don't worry, the next perihelion is just 6 months away on 4th January 2023, so get snapping away
https://www.timeanddate.com/astronomy/p ... stice.html
Alexandra
- DeepSolar64
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Re: July Solar Challenge
I have some close to aphelion ones now come perihelion in 6 months I'll have to do this! I'll use the SMII60.
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
- Montana
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Re: July Solar Challenge
I have finally processed my images from Sunday and I had a play this evening. Not perfect but it was the thought that counts
2022-07-03 CaK solar disc ap and peri size by Alexandra Hart, on Flickr
2022-07-03 Halpha solar disc peri and ap size by Alexandra Hart, on Flickr
2022-07-03 WL solar disc Peri and Ap size f colour by Alexandra Hart, on Flickr
Alexandra
2022-07-03 CaK solar disc ap and peri size by Alexandra Hart, on Flickr
2022-07-03 Halpha solar disc peri and ap size by Alexandra Hart, on Flickr
2022-07-03 WL solar disc Peri and Ap size f colour by Alexandra Hart, on Flickr
Alexandra
- DeepSolar64
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Re: July Solar Challenge
Very nice Alexandra. The apparent size difference is easy to see.
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
- Averton
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- Averton
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Re: July Solar Challenge
We didn't have an image from 4 January, the closest was 29 December but we did take an image on 4 July.
Both images are taken with our 72ED with a Meade white light filter and an ASI178 camera.
The apparent diameters of the sun are taken from Stellarium on date and time of the image capture.
The pixel measurement of the images was done in GIMP.
For a full size image see https://www.flickr.com/photos/153787832 ... 203787441/
Both images are taken with our 72ED with a Meade white light filter and an ASI178 camera.
The apparent diameters of the sun are taken from Stellarium on date and time of the image capture.
The pixel measurement of the images was done in GIMP.
For a full size image see https://www.flickr.com/photos/153787832 ... 203787441/
Clare & Peter
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Re: July Solar Challenge
That's excellent!!! a great presentation and easy to see the difference
Alexandra
Alexandra
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Re: July Solar Challenge
As an interesting additional exercise we calculated the FOV of our 72ED using the ASI178 camera.
We then determined the percentage of the FOV required by the sun at perihelion and aphelion and then the pixels used in each case.
Our 72ED actually has a focal length of 432.7mm at focus with this camera as measured by our astrophotography software.
Focal length 72ED 432.7
ASI178 X dimension (mm) 7.4
ASI178 Y dimension (mm) 5
ASI178 X pixels 3096
ASI178 Y pixels 2080
X FOV (min) 58.7920640254415
Y FOV (min) 39.7243675847578
Sun apparent dia Perihelion (min) 32.5145
Sun apparent dia Aphelion (min) 31.4488
pixels used to display sun @ perihelion 1712.21904977581
pixels used to display sun @ aphelion 1656.09910816988
This gives an answer very close to the measured values on the two images.
1712 vs 1711
1656 vs 1655
Quite surprising
We then determined the percentage of the FOV required by the sun at perihelion and aphelion and then the pixels used in each case.
Our 72ED actually has a focal length of 432.7mm at focus with this camera as measured by our astrophotography software.
Focal length 72ED 432.7
ASI178 X dimension (mm) 7.4
ASI178 Y dimension (mm) 5
ASI178 X pixels 3096
ASI178 Y pixels 2080
X FOV (min) 58.7920640254415
Y FOV (min) 39.7243675847578
Sun apparent dia Perihelion (min) 32.5145
Sun apparent dia Aphelion (min) 31.4488
pixels used to display sun @ perihelion 1712.21904977581
pixels used to display sun @ aphelion 1656.09910816988
This gives an answer very close to the measured values on the two images.
1712 vs 1711
1656 vs 1655
Quite surprising
Clare & Peter
- Carbon60
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Re: July Solar Challenge
Good challenge, Alexandra.
Here's my contribution. I have to confess that the scales may not be perfect as I make mosaics and crop when I create my original images, so the actual image scale changes every time. Therefore, these are more art than science. Also, I couldn't image 'on the day' because of the weather, so 'my Aphelion' image was taken a week after the actual Aphelion.
Anyhow, here we go:
Aphelion_Perihelion_CaK_2022 by Stuart Green, on Flickr
Aphelion_Perihelion_Ha_2022 by Stuart Green, on Flickr
Stu.
Here's my contribution. I have to confess that the scales may not be perfect as I make mosaics and crop when I create my original images, so the actual image scale changes every time. Therefore, these are more art than science. Also, I couldn't image 'on the day' because of the weather, so 'my Aphelion' image was taken a week after the actual Aphelion.
Anyhow, here we go:
Aphelion_Perihelion_CaK_2022 by Stuart Green, on Flickr
Aphelion_Perihelion_Ha_2022 by Stuart Green, on Flickr
Stu.
H-alpha, WL and Ca II K imaging kit for various image scales.
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
- Carbon60
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Re: July Solar Challenge
Really nice, Alexandra. I like the ‘3D feel’ to these.
Stu.
H-alpha, WL and Ca II K imaging kit for various image scales.
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
Fluxgate Magnetometers (1s and 150s Cadence).
Radio meteor detector.
More images at http://www.flickr.com/photos/solarcarbon60/
- Montana
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Re: July Solar Challenge
Great presentations Stuart I don't think it really matters about exact timings because the Sun and Earth take 6 months to move close and apart also, mine are mosaics too, I bet that won't make much difference either it is the fun that counts.
Alexandra
Alexandra
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Re: July Solar Challenge
Nice work Stu! The difference is easily seen.
Lunt 8x32 SUNoculars
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "
Orion 70mm Solar Telescope
Celestron AstroMaster Alt/Az Mount
Meade Coronado SolarMax II 60 DS
Meade Coronado SolarMax II 90 DS
Meade Coronado AZS Alt/Az Mount
Astro-Tech AT72EDII with Altair solar wedge
Celestron NexStar 102GT with Altair solar wedge
Losmandy AZ8 Alt/Az Mount
Sky-Watcher AZGTI Alt-Az GoTo mount
Cameras: ZWO ASI178MM, PGR Grasshopper, PGR Flea
Lunt, Coronado, TeleVue, Orion and Meade eyepieces
Visual Observer
" Way more fun to see it! "