astrofilm filter

[Langaandy]

Hi all,

im buying http://www.ozscopes.com.au/baader-astrosolar-safety-film.html and i just want to know should this cover the full apeture or should i set it up with a reduction ring becuase i have seen it done both way, my scope is 6" atm

[ZeroID]

I'm in the same quandary. I think I'll build mine for almost full aperture but make a couple of masks with smaller holes that can go on top to reduce the area exposed. Options, always options...
Good luck, take care.

Brent

[jjjnettie]

I've only ever viewed and imaged the Sun through a filtered 2" aperture reduction hole in the dust cap.
I mean, look at the PST's, they have only a 40mm aperture.
That will leave you with heaps of film left over to make a filter for your finder scope and binos.

[Poita]

I'd go the other way and use a full size filter and aperture it down if you see the need.

The first thing I did with my 40mm PST was upp the aperture to 80mm via modifications. The resolution at 40mm was considerably less than at 80mm. The view through the SCT with solar filter is the best out of all of my scopes with white light solar filters on them.
You can always cut the filter down later if you change your mind.

[brian nordstrom]

:) I agree with Peter , the view of the sun with my full apeture Kendrik white light filter is the best I have seen , beller than my 1000 oaks filter on my ed80 .
It must be the extra apateure of the 127mm triplet .
One more thing the purple colour of the suns disc is only see in photos , as the naked eye view its white ? Strange .
Brian .

[JB80]

I haven't had any issues using a full arpeture filter with my 6" scope.
Full arpeture should get better resolution in the end.

[ZeroID]

Solar film arrived. Spent about 3 hours finally getting a smooth finished cell (well nearly) which slips inside the lightsheild of the 80 mm. I can then use the front cap with it's smaller centre hole if I need to cut the aperture down.
The cell just slides down inside the lightsheild, no way will it get blown off or knocked. Just need some sun to test it out now, it's been total cloud cover or rain from the last three days. :shrug:
I'll be working that day obviously so might bring the scope into work and do a wee bit of 'Outreach' at the same time. Just got to get the clouds to cooperate. :rolleyes:

[brian nordstrom]

:question: Hey, HEY ,,, :sadeyes::sadeyes::sadeyes: Brent , BE CAREFUL HERE !!! ,,,
:sadeyes::sadeyes::sadeyes:

DO !! you realise that the solar filter has to be wrinkled ? eg left loose .

:sadeyes::sadeyes:
If its streached to taught , like you describe what you have done , it may tear under the suns heat , :sadeyes: VERY !!! Dangerous mate .
The wrinkles wont hurt the view at all , please Check this as the sun wont take any prisoners . :sadeyes::sadeyes::sadeyes::sadeyes :, give it some major thought Brent .
Be Careful !!! if it tears ,
Instant irreversable BLINDNESS :sadeyes::sadeyes::sadeyes:.
Brian.

[ZeroID]

S'Alright Brian, it is not stretched in any way. In fact it is sitting loose between two sheets of very stiff cardboard. Taped the edge but the film is just 'floating' unsecured so it can move ok. And no creases or wrinkles but it is not drumhead tight for sure.
I was more concerned with making sure there were no edge leaks or the possibility of it being dislodged. The lightshield is extremely difficult to pull off and the cell is right down against the objective and the front surface about 30 mm away from front edge of lightshield so feeling pretty safe with the arrangement.
Weather is improving so the weatherman says so it will get a test out shortly I hope.

[alistairsam]

Brent,

any pics of your handiwork?
I have an 8" Dob and an ST80. Not sure which'll be better. the 8" would have a higher magnification due to its longer focal length.
I was thinking of using a QHY5 in video mode at prime focus so I can possibly hook it up to my Plasma ??
Might have to call in a sickie that day though.
Also, is the Baader film better than the mylar?

[Shark Bait]

I have used both and I prefer the Baader Solar Film. The Sun presents in true white light. Mylar gives the Sun a slightly blue tint, but it still does the job.

[wayne anderson]

I am now ready for the transit of Venus, I decided to try full aperture for my 12” LX200 as many have commented that full aperture gives better resolution so I managed to get some Baader Visual AstroSolar Filter Material from Sirius Optics, stocks of solar filters and film are very low as you would expect, the largest sheet they had was 250mm x 500mm, I really needed at least 310mm x 310mm for full aperture so I managed to get around the problem and go full aperture by changing the usual simple design to the one shown below using thick cardboard, It works great, the sun showed a sharp white disc with great detail in the sunspots and the surface showed a slight orange peal like texture. Eyepieces used were Televue Panoptic 41mm, Ethos 17mm and 2x Powermate at magnification of 74x, 148x, and 179x. the design allowed me experiment and view using 1, 2, 3 or 4 quadrants for viewing, by viewing with only one quadrant open the resolution does suffer noticeably, so going full aperture was a good idea in this case.

[alistairsam]

Hi Wayne,

That looks good. Have you tried taking an image with it?

[Shark Bait]

:thumbsup: Nice filter Wayne. I used the 50mm stop down on the dust cover for the 12" dob and am impressed with the quality of the views. Tempted to go full now.

+1 for some photos of the Sun.