Trumpler 10 in Vela
Jos� Joaqu�n P�rez Guy
Dear Group, Trumpler 10 is a less known open cluster in Vela. I managed to get roughly 8 hours of data on this on January 2015.http://www.astro-austral.cl/imagenes/starclusters/Trumpler10/info.htm ![]() -- José Joaquín Pérez Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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Roland Christen
This is a very deep image which brings out some interesting faint detail. The small orange nebulosity is intriguing.
The image also brings out some limitations of the imaging system when used for very faint observations - basically the filters or other surfaces near the focal plane are forming out of focus halos around bright stars. I wonder if this is also a problem for the large observatories on an object like this. And of course lots of diffraction spikes which are unavoidable with reflective systems that have spiders.
If we have time, I may try imaging this with the Mak-Cass at Las Campanas, which has different filters and no spider vanes.
Rolando
-----Original Message-----
From: PEREZ, José Joaquín cotejardinero@... [ap-gto] [ap-gto] To: tekic545@... [ap-gto] Sent: Fri, Mar 13, 2015 4:10 pm Subject: [ap-gto] Trumpler 10 in Vela
Dear Group, Trumpler 10 is a less known open cluster in Vela.
I managed to get roughly 8 hours of data on this on January 2015.
http://www.astro-austral.cl/imagenes/starclusters/Trumpler10/info.htm ![]() --
José Joaquín Pérez
Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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Jos� Joaqu�n P�rez Guy
Thanks Roland. And yes, you are right. As using a newtonian one gets difractions spikes that I personally don't dislike. Fast optics let me get faint details in relatively short time, but I concerned about the halos around the brightest stars.
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José Joaquín Pérez Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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Roland Christen
What is the instrument that you used? I think the Astrodon filters are very good and do not produce halos. We have Astrodons on our Chile scope, so we will see if this is the issue or not. Since the halos are sharp edged and centered on all the stars, they are not being produced by the main optics, but by something near the focal plane. It could be the cover glass that is near the chip. Some cameras have cover glass which only has a single layer coating on the two surfaces, which reflects a lot of blue. This could be the source of the reflections.
Rolando
-----Original Message-----
From: PEREZ, José Joaquín cotejardinero@... [ap-gto] [ap-gto] <ap-gto@...> To: tekic545@... [ap-gto] Sent: Fri, Mar 13, 2015 6:08 pm Subject: Re: [ap-gto] Trumpler 10 in Vela
Thanks Roland.
And yes, you are right. As using a newtonian one gets difractions spikes that I personally don't dislike. Fast optics let me get faint details in relatively short time, but I concerned about the halos around the brightest stars.
2015-03-13 19:34 GMT-03:00
chris1011@... [ap-gto]
<ap-gto@...>:
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José Joaquín Pérez
Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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Jos� Joaqu�n P�rez Guy
Mmmmmm....I see I used my beloved ST11K.
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José Joaquín Pérez Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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Roland Christen
>>An if this is really the cause of the problem, can I do something with this cover glass? >>
A good question. I don't know if a modern multi-coated cover glass can be purchased from SBIG. Anyone?
Rolando
-----Original Message-----
From: PEREZ, José Joaquín cotejardinero@... [ap-gto] [ap-gto] To: tekic545@... [ap-gto] Sent: Fri, Mar 13, 2015 6:22 pm Subject: Re: [ap-gto] Trumpler 10 in Vela
Mmmmmm....I see
I used my beloved ST11K.
2015-03-13 20:16 GMT-03:00
chris1011@... [ap-gto]
<ap-gto@...>:
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José Joaquín Pérez
Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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BTW I believe that the “orange” blob is planetary nebula PLN 263 +0.1 I, however, am not an expert!
Mag. 7 Skies!
Howard Hedlund Astro-Physics, Inc. Phone: 815-282-1513 Please include this e-mail with your response.
P Consider the environment before printing this e-mail.
From: ap-gto@... [mailto:ap-gto@...]
>>An if this is really the cause of the problem, can I do something with this cover glass? >>
A good question. I don't know if a modern multi-coated cover glass can be purchased from SBIG. Anyone?
Rolando
-----Original Message-----
From: PEREZ, José Joaquín cotejardinero@... [ap-gto] [ap-gto] <ap-gto@...> To: tekic545@... [ap-gto] <ap-gto@...> Sent: Fri, Mar 13, 2015 6:22 pm Subject: Re: [ap-gto] Trumpler 10 in Vela
Mmmmmm....I see I used my beloved ST11K. An if this is really the cause of the problem, can I do something with this cover glass?
2015-03-13 20:16 GMT-03:00 chris1011@... [ap-gto] <ap-gto@...>:
What is the instrument that you used? I think the Astrodon filters are very good and do not produce halos. We have Astrodons on our Chile scope, so we will see if this is the issue or not. Since the halos are sharp edged and centered on all the stars, they are not being produced by the main optics, but by something near the focal plane. It could be the cover glass that is near the chip. Some cameras have cover glass which only has a single layer coating on the two surfaces, which reflects a lot of blue. This could be the source of the reflections.
Rolando
-----Original Message----- Sent: Fri, Mar 13, 2015 6:08 pm
Thanks Roland. And yes, you are right. As using a newtonian one gets difractions spikes that I personally don't dislike. Fast optics let me get faint details in relatively short time, but I concerned about the halos around the brightest stars. What do you think? Can I do something about the filters (I´m using Astrodon), the Wynner corrector or it will be a condition to live with?
2015-03-13 19:34 GMT-03:00 chris1011@... [ap-gto] <ap-gto@...>:
This is a very deep image which brings out some interesting faint detail. The small orange nebulosity is intriguing.
The image also brings out some limitations of the imaging system when used for very faint observations - basically the filters or other surfaces near the focal plane are forming out of focus halos around bright stars. I wonder if this is also a problem for the large observatories on an object like this. And of course lots of diffraction spikes which are unavoidable with reflective systems that have spiders.
If we have time, I may try imaging this with the Mak-Cass at Las Campanas, which has different filters and no spider vanes.
Rolando
-----Original Message-----
Dear Group, Trumpler 10 is a less known open cluster in Vela. I managed to get roughly 8 hours of data on this on January 2015. After reducing data I found a lot of other interesting objects as Vela's SNR filaments, NGC2671 cluster and nebulosity from a "GUM" object. There is a little orange nebulosity at the right side that I was unable to identify. Somebody knows its designation? Here´s the link
Thanks for looking and best regards!
José Joaquín Pérez
José Joaquín Pérez
José Joaquín Pérez
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Jos� Joaqu�n P�rez Guy
Thanks Howard for the info!
toggle quoted messageShow quoted text
Best regards,
El viernes, 13 de marzo de 2015, Howard howard@... [ap-gto] <ap-gto@...> escribió:
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Enviado con Gmail Mobile
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James Janusz <jjanusz@...>
That is the most beautiful and interesting open cluster I have
seen. When I saw the original post I thought, "another boring open
cluster" wow, was I wrong.
toggle quoted messageShow quoted text
Rolando. Regarding the halos. I'm suffering from the same issue with my Honders. The same camera and filters gave almost no halos with my old 17"CDK. Now that I'm using the Honders I see them all the time on bright stars. Assuming that it is the camera or the filters, (AD latest generation) what could be the cause of them showing up with the Honders? Don G. thinks it's the camera but I still do not understand why they were 90% less noticeable with the CDK. Any help is appreciated. Jim On 3/13/2015 4:56 PM, chris1011@...
[ap-gto] wrote:
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Roland Christen
The Honders cannot create halos, it is not optically or physically possible. All halos are caused by optical surfaces very close to the chip (i.e. cover glass, filters etc). The halos are there of course with the 17" CDK, however they are smaller diameter and you may not have noticed them from the glare of the star itself. In the Honders, the halos from two cover glass reflections are many times larger because the speed of the instrument is many times faster. In other words, for the same out of focus distance an F8 has a smaller blur circle than an F3.8. On top of that, a short focus instrument concentrates the energy of the star itself to a smaller glare circle, so now you see a larger difference between the star and the halo.
There is a wonderful explanation of halos caused by cover glass on the web, and in fact you can calculate exactly which glass surface causes the halo. Here are some references just by Googling (which you can do too ;^):
-----Original Message-----
From: James Janusz jjanusz@... [ap-gto] To: ap-gto Sent: Sat, Mar 14, 2015 1:41 pm Subject: Re: [ap-gto] Trumpler 10 in Vela That is the most beautiful and interesting open cluster I have seen. When I saw the original post I thought, "another boring open cluster" wow, was I wrong. Rolando. Regarding the halos. I'm suffering from the same issue with my Honders. The same camera and filters gave almost no halos with my old 17"CDK. Now that I'm using the Honders I see them all the time on bright stars. Assuming that it is the camera or the filters, (AD latest generation) what could be the cause of them showing up with the Honders? Don G. thinks it's the camera but I still do not understand why they were 90% less noticeable with the CDK. Any help is appreciated. Jim
On 3/13/2015 4:56 PM,
chris1011@... [ap-gto] wrote:
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Jos� Joaqu�n P�rez Guy
Thanks for the compliments James! Really appreciate it (<:
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José Joaquín Pérez Rancagua_Chile http://www.astro-austral.cl http://www.eso.org/public/outreach/partnerships/photo-ambassadors.html#perez
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