Featured Stargazing Solar imaging and techniques

perimeter isn't the important measurement, it is almost 5x the diameter .... that's the important value

remember we are looking at length of prominence say 60,000km round figures
diameter of the Earth 12,700 km round figures. The Earth fits INTO that prominence 4.7x ( 5x if you go out to the 65,000km measurement)

Three Earths side by side will fit through that dark centre part of the loop....




now that is significant

Dave

 

Haven't been able to do any solar imaging for a bit over a month, mainly due to cloudy skies and or lack of activity on the sun
I could have imaged last Saturday 7th April very clear sky and some good prominences.
Only problem was that it was 35C outside and the heat was unbearable to be in for more than a few minutes,
let alone the amount of time to set up the scope and computer and do imaging. That would have taken at least 30mins,
28 - 29 mins more than I was prepared to endure

How does an astronomer overcome bad condition "blues" ...... buy some more gear

So here is my new scope .... A Skywatcher EVOSTAR120 Black Diamond refractor
120mm objective lens and a 1000mm focal length giving a f-stop of 8.3
f-stop (ratio) = FL / aperture = 1000 / 120 = 8.33333....

It's been around 45 years since I last owned a refractor scope (discounting finder scopes)
This scope will get used for visual observing and imaging of solar, planetary, lunar and deep space
The camera in the photos below is the ZWO ASI 1600MM

Visual observing setup ... eyepiece and diagonal....



visible light imaging.....



Solar Ha imaging through a Daystar Chromospheric filter.....



close-up of the filter and imaging setup......





cheers
Dave

 

cheers

lots of sun, but it's been mainly during the week days when I am at work and now that we are getting well into autumn, the days are getting shorter and daylight saving ended easter weekend so the sun is too low in the west for me to observe by the time I get home from work.
Weekends are my only chances for solar observing now.

quite light the tube, mounting rings and that green mounting bar total around 5.5kg

yeah, I know that feeling with my Celestron 9.25" Schmitt-cass .... It's quite heavy

a home observatory is out of the question for me
1... primary reason ... I'm renting the property
2... I'm deep in the red zone of light pollution for doing nite time astronomy

Back in NZ, I had a 2.5 x 2.5m garden shed obs. that I made the roof roll off

just googled it, nice looking scope does your one have the 10:1 Crayford fine focuser ?
http://www.skyatnightmagazine.com/review/telescopes/sky-watcher-equinox-80-ed-apo


cheers
Dave

 

this one ?

http://www.skywatcherusa.com/product/esprit-80mm-ed-triplet-apo-refractor/

haha yeah, that is pretty typical and every astronomer within a couple of 100 km's can blame you for the cloudy skies

Don't know if you read @sophiecentaur 's post #130, he has the 80mm Equinox



Dave

 

grrrr .... been there too in days gone by

yup, that's where you can use some of narrow band filters .... they give weird colours but still give awesome results in heavily light polluted areas
I haven't gone that path as yet. I just travel around an hour out of the city area to get to darker areas.

cheers

For the Daystar Quark as shown in my photo above, it can handle up to 150mm objective before a ERF is needed
I bought the 120mm scope rather than the 102mm with the thought that I can always stop it down to ~ 100mm. This would still give a 40mm improvement over the Lunt 60mm scope and it would also kick the f-ratio up a bit to improve image sharpness over it's f8.3 @ 120mm

The Baader filters are good white light filters and I will still use my one for sunspot imaging ( not that there are many of them lately .... solar minimum)


Dave

 

sweet ! ... really nice looking scope and quite compact
What sort of mount do you have for it ?

I'm assuming, awaiting confirmation from @sophiecentaur , that it is this one ......
https://www.teleskop-express.de//sh...ox-80---80-500mm-Apo-with-aluminium-case.html

a good looking scope

 

The Sun in Ha 13 Apr 2018

Been off work all week with a not nice case of bronchitis, am feeling very unwell
but did decide to haul the gear out today and do some solar imaging
Reasonably quiet, 4 or 5 small filaments across lower part of disk, 2 groups of prominences on opposite limbs.
The new active region has moved further onto the disk and is showing an associated filament ...
The seeing conditions were better than yesterday
Lunt LS60THa, ZWO ASI1600MM and SharpCap capture software












Cheers
Dave

 

nice mount

that now begs the question ..... what is the other scope ?

 

the one you see in my posts #102 and #129 is the Skywatcher HEQ5 PRO, also a good solid mount :)

Sweet !!

My main scope is the Celestron CPC925, bought that at the beginning of 2012, it's a fork mount scope on an Al/Az mount

without going back through pages of posts, I cant remember if you have any sort of solar filter

I commented to Sophicentaur a few posts ago that the Baader filters are good white light filters for sunspots, and some other visible light surface features. It can be purchased as a roll or sheet of film
quite cheaply. I bought a roll of it, enough to make several filters for scopes and camera lenses etc.

eg .....
https://www.ozscopes.com.au/baader-astrosolar-safety-film-large-100cm-x-50cm.html
https://www.ozscopes.com.au/accessories/eyepieces/filters?p=3

the first link is the one I got .... will do many filters

dunno where you live, probably some where with sales closer to you



Dave

 

yup, the 1000 Oaks W/L filters are good, I have 2 of them one for the CPC925 and one for the 100-400mm Canon camera lens


hadn't seen this system before ....
http://thousandoaksoptical.com/shop/h-alpha/h-alpha-9-angstrom-complete-system/

just be aware that at 0.9A you are not likely to see the filaments on the face of the disk ( at minimum only a hint of the very largest ones)
as you can see from their supplied images ... the surface features are very blurred
0.9A is quite a broadband bandwidth. for every 0.1A you drop in bandwidth, the features become sharper and sharper
so dropping from the 0.9A down to the 0.65 - 0.7A of my Lunt system lots more details appear.
Dropping to the 0.45 - 0.5A, of my Daystar Chromospheric filter, is even better for surface/disk face features

I would suggest you do some research on the different filters and spent the most your budget can afford ...
it will possibly save disappointment and having to pend a whole bunch more money later on

when buying expensive gear, I'm a firm believer in the saying "do it once, do it right"

you have spent good money on excellent scopes .... DON'T skimp on a lesser quality a Ha solar filter

hope that all makes sense ?

Dave

 

Take your time, wouldn't want you to have any regrets
it took me 25+ years to finally be able to afford a Ha filter/scope, their prices have dropped considerably ( also their quality has probably improved in that time)
It was only last August (2017) that I finally lashed out on the Lunt LS60Tha ... AU$2599.
The Daystar Quark Chromosphere one came a month later at around AU$1600 (~US$1295)

My wish list for another filter, if I could afford it, a Calcium-K filter. It gives a very different view of the disk features



Photo credit: Guilherme Grassmann

he is one of the member s of the
Uk Solar Imaging & Observations. on facebook

a good group to see what people are up to with solar observing



Dave‎

 

The Sun in Ha 21 Apr 2018
Absolutely crap seeing conditions... even the "blue" parts of the sky between the cloud gaps had a high haze.
Nice new active region with spots and a nice prominence showing a large detached section
Lunt LS60THa, ASI 1600MM camera and Sharpcap capture software

Full Disk




AR2706




large detached prominence





Dave