Quick Numpty advice for sun/eclipse viewing ?

[powerlord]

Hi chaps, can some comment on some basic help on viewing eclipse/sun ?

I am going to use my MAK 102 and DSLR - I have a solar cap I made from Thousand Oaks Optical stuff, and that works fine.

And i have a solar finder to help find the thing.

But my numpty questions:

1. is there a way of seeing any detail like all the swirls and internal structure of the sun ? All I saw was a white circle ?

2. can I use something like an h alpha filter to help get some of that structure ?

3. any other tips basically ? I could use my 72ED (taping same filter on the front) and ASI224 instead.. might get me better quality fps video (well lower resolution video, but maybe better ?)

I still found it tricky to find the pigging thing, and the tracking didn't work wonderfully with my azgti.. maybe I'll try my frankenstien EQ5..

 

[rnobleeddy]

I had a practice on Saturday just incase it's not cloudy!

 

1. You should see some small sunspots (I assume they're long lived) and you may make out some granulation (I had to sharpen in Registax to see it) but to see the detail you're probably referring to requires dedicated equipment with a very narrow band pass

 

2. A filter may help improve seeing (e.g. red is less impacted by seeing) but afaik you can't simply use a glass filter to see the fine details in the sun.

 

3. I think people tend to use planetary techniques for the sun (record a video, stack the best frames) but it probably depends what you want to achieve. I can't get the full disc with a similar zwo camera so will use my 4/3ths CMOS for the eclipse as a compromise. My EQ6 tracked the sun very well on Saturday, so perhaps giving the eq5 a go would help 

[michael.h.f.wilkinson]

With white light you should be able to see some granulation, and currently a pair of sunspots (checked this morning with Lunt 8x32 SUNoculars). More detail is only visible in ultra-narrowband H-alpha or Ca-K light. The image below shows the same sunspot in H-alpha, Ca-K and white light (from a few years back, when the sun was more active).

[powerlord]

So I've got a few narrowband H alphas so sounds like they could be worth trying then...will give em a test !

[geordie85]

31 minutes ago, powerlord said:

So I've got a few narrowband H alphas so sounds like they could be worth trying then...will give em a test !

No do not do this.

Standard ha filters have a much higher band pass than solar ha filters. 

My astrodon filter has a bandpass of 3.0 and ha solar filters have a bandpass of around 0.3.

 

[powerlord]

ok, remember I am never removing the main solar filter from the front of OTA ! so surely, it can only make it darker than it was without the extra H alpha filter ?

stu

[michael.h.f.wilkinson]

40 minutes ago, geordie85 said:

No do not do this.

Standard ha filters have a much higher band pass than solar ha filters. 

My astrodon filter has a bandpass of 3.0 and ha solar filters have a bandpass of around 0.3.

 

Actually, make that 0.03 nm, rather than 3. But you are right, DSO narrow-band filters are useless for solar work. 

[powerlord]

ah, ok. so best I can hope to see is maybe a sun spot or two and the partial eclipse. fair enough. I might rake out the video I took in 1999 in Hungary when I shot a full eclipse and share it.

[Tiny Clanger]

OK, I'd not usually reply to a query in the imaging section  , but the OP did not mention imaging, simply viewing , and I've been experimenting with simple kit/solar filter myself for that so :

Finding the Sun : take bit of card out with you, hold it 30-50 cm behind the 'scope. shift the 'scope until the shadow of the tube etc shows as a neat cross section circle rather than an elongated shape. Then fine tune with the solar finder. My bit of card has a cut out and some masking tape on it, so after use to line up,  it goes on top of the tube and casts some shadow near the eyepiece. If I was viewing from a nice smooth  slabbed area I  guess I could  use the shadow of the 'scope on the ground. .

Filters: I read somewhere that a green filter might bring out some extra solar detail , but didn't find it much use, what does work for me is a UHC , sunspots are more than simple freckles,  some surrounding structure is visible .

 

 

[Nigel Rees]

If you have a narrowband filter give it a try, I found using one with a Solar filter helped with being able to under-expose the image slightly. Here's a first attempt at solar photgraphy from Saturday using a DSL:R, 300mm lens and H-alpha, Solar and green (to boost contrast) filters. So try and see what you find out

[Stu]

31 minutes ago, Tiny Clanger said:

Filters: I read somewhere that a green filter might bring out some extra solar detail , but didn't find it much use, what does work for me is a UHC , sunspots are more than simple freckles,  some surrounding structure is visible .

Yep, that’s a good idea. A continuum filter is best, but if you don’t want to invest in one just for solar, a UHC (or OIII) filter does seem to work quite well as an alternative.

@powerlord are you just imaging or viewing? With a 102mm scope you should be able to see granulation on the surface and some detail in the spots. Imaging it requires stacking and processing of video frames to bring out the detail.

[powerlord]

i thought I'd have a go at imaging it. mak102 + 1200D will fit sun in and no more.

Or I could use my 72ED and asi224- which will fit the top half in only - possibly ideal for eclipse.. and get benefit of easy video capture, etc with it (albeit at lower res than the DSLR).

Not sure which would be best really ? filter changing and focus will be easier with the DSLR - but best for stills rather than video really.

ill try UHC and a oiii too then. Ideal to try today if I had any time at all between fecking work meetings!! 😖