solar filter

[daz01968]

what is the best way to view the sun using my celestron nextstar 6       do i buy solar film and make my own filter or do i buy a glass filter ?

and where do i buy a glass filter, the only 1 i found was on ebay and comes from america and costs an extra $54 postage

can anyone help me out please

[ronin]

Likely easier to make your own, a la Blue Peter style, or find the guide on SGL somewhere.

Baader film is around £20 a sheet, you need the ND5 for visual, the ND3 is for imaging.

There is a 100x difference in transmission so make sure it is visual.

The ND5 is 10^-5 transmission, ND3 is 10^-3 transmission.

You can buy ready made, look up Solar on FLO and that may be the better option, costs a bit more but it arrives ready made and ready to use.

http://www.firstlightoptics.com/solar-filters/astrozap-baader-solar-filter.html

I have a glass one, I like it, people criticise them - not sure why, mine is excellent, it is for a Meade and was made by Astro Engineering so irrelevant for you.

[farunj]

Making one for yourself is pretty easy. There are many online tutorials to help you do it. Be careful that there are no holes in the film while you are making it.

Also, there are many people who sell solar filters which are on the eyepiece. That is BAD. Never take one of those, as they break easily and it will damage your eyes.

The only way to use a solar filter is to put it in front of the telescope on the aperture.

Sent from my Nexus 5 using Tapatalk

[Steve Ward]

I have a glass one, I like it, people criticise them - not sure why, mine is excellent, it is for a Meade and was made by Astro Engineering so irrelevant for you.

I / We / They criticise glass-based filters on a number of grounds :

Firstly , the glass used is not of "optical quality" , either in substance or finish (unless an extremely expensive Zeiss filter is in the spotlight , and with these costing as much as an Ha filter we can assume they are not ) , any piece of glass not optically polished placed in front of the 'scope will inevitably detract from the potential view to some degree.

                  This may not appear significant if used for visual purposes only (and if no direct comparison is made ) but when imaging the difference is all too apparent.

Secondly , the glass is coated on one side only , making for filter that is much more likely to come with pinholes that require attention before use , and that degrade quicker pinhole-wise. 

                 Pinholes can be 'repaired' with a Sharpie" or similar but it's an unsatisfactory scenario in my opinion.

      I had to go through a heap of Astro-engineering filters for my ETX-105 before finding a half-decent one , half-decent in that I only had to "Sharpie" a dozen or so holes before use , only to find a dozen more a week or so later , hence my switch to  Baader film and subsequent comparisons ( the nicely machined filter-cell made for an excellent holder for a Baader-based filter for the Meade once the glass was removed ... )

Baader Solar film is coated on both sides lessening greatly the likelihood of pinholes being present or developing later.  That is to say that pinholes will appear in the surface over time , but the chances of pinholes on both sides developing and lining up to cause a problem are obviously minimal.

Thirdly , a glass-based filter is , by it's very nature , a delicate beast that is easily damaged accidentally , i.e. drop it and it will inevitably break , the Baader Solar film is much more robust despite its flimsy appearance.

All in all Baader Solar film is the superior option in my opinion.

P.S.  Avoid the black polymer based filters like the plague , they are all but useless for anything other than cheap 'eclipse' glasses.