Jump to content

Banner.jpg.b89429c566825f6ab32bcafbada449c9.jpg

Getting the best out of Solar Film (visual)??


Paul73

Recommended Posts

Hi Guys

So. I've made my filter using the ubiquitous Baardar Solar Film. The sun spots are lovely with great detail (didn't realise how much they change over the course of a day). Is it possible to get much in the way of surface detail other than Sun spots? Is there any chance of seeing prominences?

Given that the solar film costs £20. I'm not getting to carried away re expectations, but would like to know what is possible.

Any hints and tips greatfully received.

Lastly, what should be my next bit of solar viewing kit? And what would it do for my viewing. Budget is limited!!

Paul

PS. My little ED80 seems to do a much better than my 10" dob.

Link to comment
Share on other sites

For proms, you'd need a dedicated H-alpha scope (or specialist filter like the Daystar Quark about 850 pounds).  With white light viewing (e.g. Baader Solar film) you can see some surface granulation, sharper detail on the sun spots, and limb darkening - darker towards the edge  https://en.wikipedia.org/wiki/Limb_darkening).  Upgrading to a Herschel wedge (also a white light observing system, replaces your ed80's diagonal) may improve the view but isn';t cheap (starting around 130 pounds).  Some filters may also make surface granulation more easy to see - the most popular at the moment is the Baader solar continuum filter, but for your ed scope, even a basic visual green filter might help (cheaper scopes might benefit more from the solar continuum filter due to the CA), but check this thread out http://stargazerslounge.com/topic/66025-baader-solar-continuum-filter/.  A variable polarizing filter, e.g. http://www.firstlightoptics.com/moon-neutral-density-filters/variable-polarizing-moon-filter.html  can help by letting you tune the brightness and make detail easier to see.

Given that you say your budget is limited, you might get best "bang for your buck", from a simple green filter, e.g. a number 56 filter, (for example, one on ebay: http://www.ebay.co.uk/itm/OSTARA-LIGHT-GREEN-56-Filter-1-25-Fitting-High-Quality-Stackable-/351347323239?hash=item51cdeeb167 )

oh and I'd stick with the ed80 for solar observing

btw, unless you're using the herschel wedge all those other filters still need the solar film.  I hope that's obvious but I have to say it :)

Link to comment
Share on other sites

If you've got a Oiii filter you could try that, I believe the band pass is very similar to the continuum filter, I've noticed a difference with a ST80 and baader film using this filter..

Failing that, the next biggest jump in quality of view, I found, was the Lunt wedge in a 72mm ED..  The views here in the uk were as good with this combo as they were in Corfu with an 80mm Achro and film... (im anticipating corfu might have better observing conditions, on average)

Ta

Fozzie

Link to comment
Share on other sites

Hi Guys

A quick update. Today I tried a small selection on astromomical filters on the eyepiece end and the solar film on the other end.

The ND 0.9 moon filter and the OIII worked best in getting some surface texture. Certainly nothing startling but an improvements none the less. This could just be down the image being dimmed just enough to show a bit more contrast.

The Green sun through the OIII was certainly surreal.

Paul

Link to comment
Share on other sites

I agree with the 1.25" Lunt wedge. It's provided the best WL views of the sun I have ever had on my 120ED and 80ED.A used PST is the cheapest option for Ha observing which is very different to WL. I spent some more and went for a PST / Tal mod stage two and this is great value.

Link to comment
Share on other sites

There were some lovely areas of faculae showing today towards the limb, sort of bright streaks I suppose they appear as.

Granulation was ok today although there was high haze and seeing wasn't great. Early morning is best as the atmosphere is calmer then

Link to comment
Share on other sites

And try to avoid "chasing the seeing" as far as focus is concerned , the atmosphere can be very turbulent when the Sun's had a chance to warm up your surrounding environment .

As with planetary viewing it's better to carefully watch to start with while adjusting initial focus until you see moments when the detail just pops out at you , at that position just leave the focuser alone and view , the details will emerge ... maybe only fleetingly ... but they will appear - and disappear - and appear .....  :smiley:

To give you an idea of how it can be , I shot 300 frames today for my full disc image , the focus was absolutely nailed .... ( using a USB controller giving around a 250:1 fine adjustment ) .... out of those 300 frames only 22 were deemed by me to be worthy of stacking , the rest ranged in quality from "nearly there " to "atrocious" , all due to the atmosphere ...  :embarrassed:

Link to comment
Share on other sites

Not necessarily , there's good seeing to be had at all times of year ...  :smiley:

Thing with Solar viewing is that the Sun is the most dynamic object up there , it's not like looking at M42 which looks exactly the same this year as it did last , it is constantly changing it's appearance so I would never let an opportunity to observe go begging .

Problem most folk have during the late Autumn through early Spring is it's low altitude , unless you have a clear low horizon from South-East through South-West you will undoubtedly have problems viewing in the early morning and late afternoon as greenery tends to start interfering with line of sight , thus limiting viewing time to around lunchtime when it's at it's highest in the sky. This unfortunately usually coincides with the poorest seeing of the day.

Extreme measures were taken by yours truly to get over the elevation problem regards to imaging , I built a fourteen foot tall pier to get a decent line of sight over the trees in order to try and  get a shot every day of the year , worked well enough to net me 311 from 365 last year ... a little drastic but needs must when the obsession takes a grip ... can't say I'd want to be perched up there at the eyepiece though ...   :p

Link to comment
Share on other sites

Or a Quark.

A Quark!!! True, the phrases "low cost" and "affordable" do appear on their website........ Great pieces of kit though.

Better than a PST? I was lucky enough to have a look through a fellow SGLer's Bino Double Stacked PST (2xPST with the add on). These were mounted on something that could have handled a reasonable sized machine gun! What a setup! What a view!

In fairness, not a great comparison. A PST vs Quark on a reasonable APO???

Scratch that. New thread needed for a cloudy Saturday. (my smiley emos have disappeared).

Paul

Link to comment
Share on other sites

If you, like me, can't justify spending our last £$ € on solar-wedges, Quarks, dedicated-scopes, etc. - and film will be it until we strike gold - then I do suggest a Baader Solar-Continuum Filter (FLO has 'em). While a simple Green #58 is a very good second choice, the Baader will let you tease out a bit more detail in spotting granulation on the solar-disk. If you happen to have a bunch of other filters (I have enough to choke a Plutonian), by all means try them. Stack 'em. See where you go and what you find. This is, after all, one of the real joys of our observational hobby! Maybe you'll end up inventing the "Phaser." And be rid of the neighbor's nasty outdoor light in the bargain ( hope the Mod-Squad doesn't truly believe this qualifies as a unlawful activity... :icon_mrgreen:)!

I recently found that Orion-USA had some cheap solar-filters made from film made by Thousand Oaks in California. These give one a very nice Orange-Yellow image - instead of the Baader-film which gives a (too bright many say) white image. They have only two - one fits a 8X or 9 X 50mm Finder-Scope. The other fits an 80mm refractor such as an ST80 or ED80:

http://www.telescope.com/Orion-400-ID-E-Series-Safety-Film-Solar-Filter/p/102779.uts?keyword=Solar%20Filters

Though I haven't ordered from here in years (and it was for something else), Thousand Oaks themselves are certainly worthy of a look:

http://www.thousandoaksoptical.com/solar.html

I hope you can use this info.

Sunny Skies,

Dave

Link to comment
Share on other sites

I recently found that Orion-USA had some cheap solar-filters made from film made by Thousand Oaks in California. These give one a very nice Orange-Yellow image - instead of the Baader-film which gives a (too bright many say) white image. They have only two - one fits a 8X or 9 X 50mm Finder-Scope. The other fits an 80mm refractor such as an ST80 or ED80:

http://www.telescope.com/Orion-400-ID-E-Series-Safety-Film-Solar-Filter/p/102779.uts?keyword=Solar%20Filters

Though I haven't ordered from here in years (and it was for something else), Thousand Oaks themselves are certainly worthy of a look:

http://www.thousandoaksoptical.com/solar.html

I hope you can use this info.

Sunny Skies,

Dave

Both those polymer film filters give vastly inferior views compared to the Baader film and are fit only for use as eclipse glasses .

You will never see as much detail using them , or any glass-based filter for that matter , as you will with Baader Solar Film ...  :rolleyes:

Link to comment
Share on other sites

Yes. The Baader Solar Film does seem to be ridiculously good value. £20 and 15 mins gets you great Sun Spots, some granulation and safe solar viewing.

In Astro terms, this is virtually free!

Paul

Link to comment
Share on other sites

There's no accounting for taste ...  :rolleyes:

Personally having tested all three extensively , both visually and more importantly for imaging , there was only one winner , by a country mile ...  :p

The 1000 Oaks R-G film is not too bad but the glass filters are not made with anything like optical quality glass and the lack of fine detail is very apparent up close , the only glass filter ever made with optical precision were the Zeiss SFO filters , but prices were prohibitive in the day ... on par with cheap Ha kit today.  And glass filters are only coated on one side making them very susceptible to pin-hole problems , Baader film is double-sided as regards to coatings making pinholes very rare .

And glass filters don't bounce too well either.

But I wish you clear blue skies nevertheless , happy viewing ...  :smiley:

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. By using this site, you agree to our Terms of Use.