Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_the_milky_way.thumb.jpg.dbd8b15e81d11e9303c8d6ef1898ac08.jpg

Buzzard75

Prepping for 2024

Recommended Posts

I was blessed to live in the US within a few hours driving distance of the path of totality for the eclipse last year. The next total eclipse visible in the US happens to be going right over top of my parents house so I'll be traveling for that one as well. Having seen the last one through both white light filters, PST's, telescopes with H-alpha filters, and a regional science centers observatory scope (it was rather impressive), I decided I want to get a setup squared away for the next one. First off, I have a 12" dob with an off-axis white light filter, but I would also like to do some H-alpha observation to be able to see the chromosphere and prominences as well. White light is all well and good if there's some sunspot activity going on at the same time, but otherwise it's just going to show the moon as it passes across the sun which isn't super dramatic. Some of my family and friends have never been fortunate enough to be able to see an eclipse or even observe the sun for themselves and I want to show them as much as I can. Secondly, I need a bit of an education in solar filters and equipment.

First question, is it even possible for me to do solar H-alpha observation of the chromosphere and prominences with a dob? If so, what do I need? I've been searching and reading and, if I'm understanding it correctly, I would need an energy rejection filter (ERF) and a H-alpha filter like a DayStar Quark. Is that really all I would need? If it's not possible, why? What's so different about a dob from any other telescope that prevents you from using it for H-alpha?

Thanks in advance!

Share this post


Link to post
Share on other sites
12 hours ago, Buzzard75 said:

First question, is it even possible for me to do solar H-alpha observation of the chromosphere and prominences with a dob?

yes of course, I will assume your dob may not be motor driven, so you will be constantly adjusting position to keep the sun in view

 

12 hours ago, Buzzard75 said:

If so, what do I need? I've been searching and reading and, if I'm understanding it correctly, I would need an energy rejection filter (ERF) and a H-alpha filter like a DayStar Quark. Is that really all I would need?

 

firstly, you don't need a 12" aperture, the sun is a "freakin bright " object, so chasing those elusive photons isn't an issue  :icon_biggrin:

I would be stopping down the aperture to a max of around 4" (100mm) and an ERF will be needed,  if you stop to 80mm or less, you wont need an ERF.

Daystar state clearly in their paperwork that 80mm aperture is the absolute max without an ERF

I use a Quark on my Canon 100-400mm zoom which is 80mm aperture and works well with the  Quark

Yup, the daystar Quark goes into the eyepiece holder and you eyepiece in the other end

 

Dave

Share this post


Link to post
Share on other sites
17 minutes ago, Davenn said:

yes of course, I will assume your dob may not be motor driven, so you will be constantly adjusting position to keep the sun in view

 

 

firstly, you don't need a 12" aperture, the sun is a "freakin bright " object, so chasing those elusive photons isn't an issue  :icon_biggrin:

I would be stopping down the aperture to a max of around 4" (100mm) and an ERF will be needed,  if you stop to 80mm or less, you wont need an ERF.

Daystar state clearly in their paperwork that 80mm aperture is the absolute max without an ERF

I use a Quark on my Canon 100-400mm zoom which is 80mm aperture and works well with the  Quark

Yup, the daystar Quark goes into the eyepiece holder and you eyepiece in the other end

 

Dave

Dave, this advice isn't correct so please be careful.

Although it may be possible to use a Quark with a dob, it's not something I've heard of. At very least, if attempting it a full aperture or sub aperture ERF must be used otherwise the secondary mirror is likely to get fried, same principle as an SCT. The 80mm limit will only apply to refractors.

Buzzard, if using a Quark, I would get yourself a refractor, its a lot easier and likely to give you a better result than trying with the dob. Do plenty of reaearch beforehand so you understand how they should be used.

 

  • Like 1
  • Thanks 1

Share this post


Link to post
Share on other sites

Thanks guys. My dob is a GoTo so it should be able to track with minimal corrections. I would definitely stop down the aperture with an off-axis ERF. I can't say I've ever seen or heard of anyone doing H-alpha with a dob before myself either, which is why I was asking before I even started going down that road. DayStar Quarks certainly aren't cheap though and I figure by the time I spend the money on one of those and an off-axis ERF, I could probably buy a dedicated solar scope. Just not sure I want to have more telescopes sitting around that serve a specific purpose. Maybe a refractor would be a better option and then I could potentially use it for some astrophotography work as well. Something to think about I guess.

  • Like 1

Share this post


Link to post
Share on other sites

With the Solar minimum already showing it effects on the Sun, also likely to get quiter as well. It maybe a good time to watch the 2nd hand market, as people become a little bored with all things Solar. You might be lucky and pick up a PST for around £400 maybe, depending on whether you want a dedicated Solar scope. 

An 80-100mm refractor + Baader safety film would be less than half that price, depending on the quality of the OTA. You have plenty of time, so do plenty of research and think long term not just this one event.

Edited by Pete Presland
spelling
  • Like 1

Share this post


Link to post
Share on other sites
On 1/13/2018 at 08:29, Stu said:

Dave, this advice isn't correct so please be careful.

Although it may be possible to use a Quark with a dob, it's not something I've heard of. At very least, if attempting it a full aperture or sub aperture ERF must be used otherwise the secondary mirror is likely to get fried, same principle as an SCT. The 80mm limit will only apply to refractors.

Buzzard, if using a Quark, I would get yourself a refractor, its a lot easier and likely to give you a better result than trying with the dob. Do plenty of reaearch beforehand so you understand how they should be used.

 

Yep, the secondary mirror will be fried. Eeek

White light is the only option for a big dob

https://www.cloudynights.com/topic/485056-best-solar-filter-for-a-dobsonian/

https://www.cloudynights.com/topic/486344-can-i-view-sun-flares-with-a-dob/

Golden rule: BE AFRAID OF THE SUN, IT WILL BLIND YOU AND YOU CANNOT GET NEW EYES :( 

 

Buy either a "80mm refractor & add a Quark" or just go buy a nice "Lunt solar scope". You have many years to save up :) 

Edited by alanjgreen

Share this post


Link to post
Share on other sites
On 1/12/2018 at 19:45, Buzzard75 said:

I was blessed to live in the US within a few hours driving distance of the path of totality for the eclipse last year. The next total eclipse visible in the US happens to be going right over top of my parents house so I'll be traveling for that one as well. Having seen the last one through both white light filters, PST's, telescopes with H-alpha filters, and a regional science centers observatory scope (it was rather impressive), I decided I want to get a setup squared away for the next one. First off, I have a 12" dob with an off-axis white light filter, but I would also like to do some H-alpha observation to be able to see the chromosphere and prominences as well. White light is all well and good if there's some sunspot activity going on at the same time, but otherwise it's just going to show the moon as it passes across the sun which isn't super dramatic. Some of my family and friends have never been fortunate enough to be able to see an eclipse or even observe the sun for themselves and I want to show them as much as I can. Secondly, I need a bit of an education in solar filters and equipment.

First question, is it even possible for me to do solar H-alpha observation of the chromosphere and prominences with a dob? If so, what do I need? I've been searching and reading and, if I'm understanding it correctly, I would need an energy rejection filter (ERF) and a H-alpha filter like a DayStar Quark. Is that really all I would need? If it's not possible, why? What's so different about a dob from any other telescope that prevents you from using it for H-alpha?

Thanks in advance!

Its not clear to me why you draw a correlation between solar eclipse and H-alpha observing.

You dont need a solar eclipse to use h-alpha (in fact, there will be less sun to see as it is blocked by the moon!).

You dont need h-alpha to observe an eclipse, solar glasses or solar binoculars (sunoculars) will be much simpler.

https://www.firstlightoptics.com/solar-filters/baader-solar-eclipse-observing-glasses.html

https://luntsolarsystems.com/sunocular-tm-solar-binoculars/

As you are in the US, I would save for a nice dedicated Lunt solar scope and the date you need to prepare for is 2025 (the next solar maximum) - this is the year when YOU WANT TO HAVE h-alpha :)

 

Edited by alanjgreen
  • Like 1

Share this post


Link to post
Share on other sites
10 minutes ago, alanjgreen said:

You dont need a solar eclipse to use h-alpha (in fact, there will be less sun to see as it is blocked by the moon!).

You are absolutely right, you don't NEED an Ha scope to view an eclipse, but it is certainly amazing to view an eclipse through one. Seeing the prominences either side of the 'bite' taken out of the sun by the moon was amazing during the partial eclipse we viewed at SGL10.

2025 is a long way off! Plenty of action in Ha even when the sun is relatively quiet, so don't wait until then!

  • Like 1

Share this post


Link to post
Share on other sites
7 minutes ago, Stu said:

You are absolutely right, you don't NEED an Ha scope to view an eclipse, but it is certainly amazing to view an eclipse through one. Seeing the prominences either side of the 'bite' taken out of the sun by the moon was amazing during the partial eclipse we viewed at SGL10.

2025 is a long way off! Plenty of action in Ha even when the sun is relatively quiet, so don't wait until then!

Exactly! Thats my point. Why wait until 2024 solar eclipse???????????

Although, as someone who observed the solar max of 2014 in Ha, 2017 was a pretty sparse year :( Just three huge sunspots and associated active regions the whole year. The sun has been fast asleep for the last 2 months...

Open the attached link, then change the date (top left) to 2014 to see what the sun can really do... :)

https://www.helioviewer.org/

Edited by alanjgreen

Share this post


Link to post
Share on other sites
7 minutes ago, alanjgreen said:

Although, as someone who observed the solar max of 2014 in Ha

Yep, plenty to see at max I remember.

I was responding to the 'the date you need to prepare for is 2025', no need to wait that long there is usually something to see in Ha. The bigger issue is how low the sun is currently but spring is on the way.

Share this post


Link to post
Share on other sites

Doesn't look so asleep in this image ;) 

 

Share this post


Link to post
Share on other sites

I know I don't NEED to wait until 2024 for the eclipse to view the sun in H-alpha and I know I don't NEED a solar scope to view the eclipse, however, I want to make sure I'm prepared for it. That's all. Viewing the eclipse in H-alpha was certainly an amazing sight and I've got some time before the next one to save up the funds or slowly acquire the equipment. Right now I'm just trying to decide if I want to use the equipment I already have and just get some filters, get something dedicated, or get a completely new setup that I can use for both H-alpha and possibly astrophotography. I'm leaning towards the latter, it's just going to be a lot more expensive than the other two options.

Share this post


Link to post
Share on other sites

By the time we get to 2024 there may be even better more cost effective Ha filters available.......

In the meantime you could consider an external etalon filter (Lunt or Coronado) and temporarily turn a good night time refractor into a very effective Ha solar scope.

I use the SM60 on an ED80 with excellent results.

 

Share this post


Link to post
Share on other sites

A little PST on a reasonable photo tripod is a joy to own. It takes up very little space. Mine used to stay set up in the corner of my study. If the sun appeared, I’d grab it carry it outside with one hand, plonk it down and observe. I’ve since graduated to a 100mm scope which needs proper mounting. I do a lot less solar observing now..☹️

Paul

NB. A Little Lunt does the job just as well (if not better)

  • Like 1

Share this post


Link to post
Share on other sites
24 minutes ago, Paul73 said:

A little PST on a reasonable photo tripod is a joy to own. It takes up very little space. Mine used to stay set up in the corner of my study. If the sun appeared, I’d grab it carry it outside with one hand, plonk it down and observe. I’ve since graduated to a 100mm scope which needs proper mounting. I do a lot less solar observing now..☹️

Paul

NB. A Little Lunt does the job just as well (if not better)

A very good reminder that bigger is not always better Paul. It's funny, I was having a 'lively debate' with someone on FB (quite possibly a member here, all is good :) !) about the merits of a SolarMax 90 vs a Double Stacked PST. It was basically a 'contrast vs resolution' thing.

To my mind I know I would rather have an SM90, than the PST, but your comment is very telling. Setting up either of my solar scopes is more hassle than it used to be, so I see more but less frequently..... go figure! :) 

  • Like 1

Share this post


Link to post
Share on other sites

A good debate. I couldn’t answer the question.

I have what is basically, a 100mm PST. Rather like yours. I sold the double stack unit to pay for the mod to 100mm. The proms are outrageously good in the bigun. The surface detail was much better in the little dimmer view of the PST/DS

Oviously, we need both!

Paul

 

Share this post


Link to post
Share on other sites

The great thing about ha is that there is always something interesting to observe. Often over the past year the sun's disk has been completely blank on Gong, but the view through the eyepiece always picks up on small proms or filaments that make it worthwhile. So while the next active phase frankly can't come soon enough, there's lots to enjoy in the meantime. And the PSTs and Lunt 35/50s really pack a punch.

  • Like 3

Share this post


Link to post
Share on other sites
6 hours ago, Paul73 said:

A good debate. I couldn’t answer the question.

I have what is basically, a 100mm PST. Rather like yours. I sold the double stack unit to pay for the mod to 100mm. The proms are outrageously good in the bigun. The surface detail was much better in the little dimmer view of the PST/DS

Oviously, we need both!

Paul

 

It really is a good debate and I appreciate all the input. Being able to lay out all the pros and cons for each solution from people who have experience using all different types is extremely useful for me and I'm sure others who are interested as well.

Paul, you also mentioned in one of your previous comments about getting a 100mm scope and it needing proper mounting. Is there a reason you wouldn't be able to set it up on a regular tripod for just some quick, unguided observations?

 

Share this post


Link to post
Share on other sites
On ‎25‎/‎01‎/‎2018 at 00:54, Stu said:

Doesn't look so asleep in this image ;) 

 

 

thanks for the link to my pic ;) 

there's always prominences to be had even when the sun is quiet. Have been some good ones over the last few days 27-30 Jan.  

The quiet or as some one said "asleep" sun is referring to the lack of active regions = sunspots and flares

 

Dave

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×

Important Information

By using this site, you agree to our Terms of Use.