Solar observing with a white light and Ha filter

[Ags]

If you used a white light filter (e.g. baader solar film) on the front of the scope, and a Ha filter on the eyepiece, would you see any more details (like prominences or granulation)? If not, why not? Doesn't a solar scope just filter on the Ha wavelength too?

I've been told before on the forum this won't work, but I would like to understand why.

If it does work, could you try other wacky stuff, like a H-beta filter or an OIII? Obviously I don't own any of this stuff or I would just try it out myself.

[Ad Astra]

Most H-alpha filters need a very specific energy rejection filter - mylar films can cut out the crucial part of the spectrum you are trying to see, making your fancy H-alpha filter almost worthless.

I would think the same would apply for stacking with O-III or other specialty filters.

You could try it - but I think it would be $$$ down the drain. If you want to view the sun - be smart about it! Get a filter system that is made for the purpose, and more importantly, matched to your optical system. When you observe the sun, you must take great care - you only have one set of eyes.

Dan

[johninderby]

What it really comes down to is the incredible degree of precision needed to make a solar Ha etalon. It's a very expensive process to obtain the fine tolerances needed. Then there's the blocking filter (££££) and the ERF filter (££££) of course.

An Ha imaging filter is a completely different animal with really nothing in common with a solar Ha system except the "Ha" name.

John

[Peter Drew]

The white light solar film cuts out 99.99% of the light. There would be nothing much left by the time it had passed through the Ha etalon and the blocking filter. .

[Merlin66]

I comes done to the simple fact that you need a very, very narrow bandwidth to see that Ha detail. Somewhere around 0.1nm. None of the DSO type filters come anywhere close to this requirement. Same goes for the other wavelengths.

You can't make an Ha, Cak etc solar scope from a combination of "standard" filters - just not technically possible.

[Ad Astra]

I comes done to the simple fact that you need a very, very narrow bandwidth to see that Ha detail. Somewhere around 0.1nm. None of the DSO type filters come anywhere close to this requirement. Same goes for the other wavelengths.

You can't make an Ha, Cak etc solar scope from a combination of "standard" filters - just not technically possible.

Precisely! The H-alpha band is very narrow - the trick is to reject the dangerous IR and UV, then cut the bandwidth of the filter to the narrow tolerances needed.

Fooling about with solar observation is NEVER a good idea.

Do is properly with professional equipment, or leave it alone. I've seen people damage equipment - a shattered EP from heat buildup and a burnt out CCD in one case. One shudders to think what would happen if you did a bad job rigging a filter and "just took a peek".

There are plenty of companies that make high quality solar obs. equipment. Save up your cash, do the research, then make an informed purchase and enjoy yourself.

Dan