Newbie Question Re: H-Alpha filters

[archer73]

Hiya, folks. First-timer here. I'm a photographer by trade and was wondering if I can apply h-alpha filters for solar photography the same way I would apply regular photographic filters...i.e., over the front of the lens. I've seen a lot of discussion about h-alpha filters in eyepieces and/or in dedicated solar scopes, but I'm interested in shooting the sun in h-alpha with my Canon camera and don't know if this is even doable. I ask because I've been using a standard Orion solar filter for some time but have fallen in love with the h-alpha look.

Thanks!

-Greg

[JayTee]

That h-alpha look that you love is generated by a specific type of solar telescope. These telescopes have a specific filter that let's through a very narrow band pass of light and also eliminates / reflects 99.5% of the sun's energy so you don't sustain any heat damage.

If you were to put just a simple h-alpha filter in front of your camera or even in front of the telescope objective. You would still get the detriment of all that heat going through the system. After a few seconds the filter, your camera, and everything would burst into flames --- not really, but you get the point.

So if the h-alpha look is what you are really in love with, unfortunately you're probably going to have to get a dedicated solar scope. Now there are specific types of eyepieces that will do the same thing but they are nearly as expensive as the solar scope itself.

Cheers,
JT

[Voyageur]

No. H-alpha filters that screw onto the front of a DSLR lens are for taking photos at night of nebulae with strong emission in those wavelengths. They are NOT for solar photography. You CAN get an H-alpha filter for a DSLR: google Daystar Quark camera filter. These are a specialized piece of technology in no way similar to a filter that screws onto the front of a lens. They cost $1295 for a reason.

Edit: Oops, JT beat me to the punch.

And welcome to the forum!

[archer73]

Thank you, [mention]JayTee[/mention] and [mention]Voyageur[/mention] , for your responses! In looking at the Daystar Quark camera filter, I have two follow-up questions (which may be best reserved for the retailer than here, but I'll let you decide, assuming you're familiar with the product):

1) The filter apparently doesn't accommodate electronic pass-through, which I suppose means that the lens will stop down to its minimum aperture (which in my case is f64, since I'm using a Canon 600mm f4 with a doubler on it (the lens normally stops down to f32)). Is this accurate?

2) In the product description, they mention, "Daystar recommends use of red, orange or yellow colored glass lens front filters such as Cokin, Hoya brand, etc or similar on lenses above 80mm in aperture." To me, this presupposes that one is using a lens with a smaller diameter and that could hold a screw-in filter. The diameter of my 600mm is about 7.5" at the opening of the lens hood and about 6.5" at the end of the lens. I've never heard of a screw-in filter of that size (assuming the lens even had threads in those areas, which it doesn't). Thus, how would I affix the colored glass to the end of the lens? Also, where would I even get such colored glass?

Thanks again, and my apologies if these follow-ups would be better posted elsewhere. Like I said, total newbie...

-Greg

[Voyageur]

Greg, the colored filter DayStar mentions sounds like an Energy Rejection Filter (ERF) to reduce heat entering an existing lens. DayStar sells ERFs, but it doesn't look like they have anything to accommodate a lens of the diameter of your 600mm.

It may be that the Camera Quark doesn't accommodate that particular lens (they do have a disclaimer that the product may not work for 100% of Canon lenses) so your best best is going to be to call DayStar. It is a quality product (my astro club has a 150mm refractor with ERF and Quark filter) and I'm sure they will be able to give you all the information you require.

[Lady Fraktor]

There are no f/ stops with telescopes or eyepieces (or Quarks)
The f/# that you see being used are the focal ratio of the equipment.
The terminology is the same but used differently.

[archer73]

Thank you again, [mention]Voyageur[/mention] and thank you anew, [mention]Lady Fraktor[/mention] . I'll reach out to Daystar for further info. Already loving how helpful everyone is on this forum!

[Baurice]

You need to buy a solar telescope, something called a T-ring and an adaptor to fit your T-ring to the camera. This allows you to use a telescope instead of a camera lens with a DSLR. However, be careful about using the cheaper solar telescopes. I have a Coronado PST but it only has a short focus travel, so I cannot achieve focus with a DSLR. To use a Quark, you can use an ordinary telescope and place the Quark before the T-ring.

I use a DSLR with a night-time telescope quite often and I use it during the day with a white light filter. However, this shows sunspots but not the type of features that you can see with a solar hydrogen alpha telescope.

[yobbo89]

you need a protective filter ie a solar filter or solar film (white light filter) at the front of the lense or a speciality solar scope .

a ha filter or contiuminum filter can add contrast in addition of a solar filter to enhance the photosphere . you'll need a solar scope to see proms.

[Lowjiber]

Greg, we're all glad you joined us here. I have some experience shooting the sun at the Hydrogen-alpha wavelength and certainly don't want to be a curmudgeon concerning your quest.

You've gotten some very good answers to your questions by some pretty savvy folks above, and I don't need to re-hash their answers. However, since you are a "photographer by trade" I can only assume that you want to capture the sun as well as possible.

The best solar imager in the world is a Brit named Alexandria Hart (solarnutcase). When she enters a contest, everyone else is playing for second place. In her blog, she outlines the entire process quite well here: https://solarnutcase.livejournal.com/18572.html

The last section discusses using a DSLR. I suggest reading the entire article before jumping into the frey.

From my perspective, I don't think a DSLR and your 600mm scope will provide the images that befit your goals... I may be wrong. After perusing the above article, you may agree.

We can, and will, help.

Respectfully and Clear Skies

[Baurice]

Greg, we're all glad you joined us here. I have some experience shooting the sun at the Hydrogen-alpha wavelength and certainly don't want to be a curmudgeon concerning your quest.

You've gotten some very good answers to your questions by some pretty savvy folks above, and I don't need to re-hash their answers. However, since you are a "photographer by trade" I can only assume that you want to capture the sun as well as possible.

The best solar imager in the world is a Brit named Alexandria Hart (solarnutcase). When she enters a contest, everyone else is playing for second place. In her blog, she outlines the entire process quite well here: https://solarnutcase.livejournal.com/18572.html

The last section discusses using a DSLR. I suggest reading the entire article before jumping into the frey.

From my perspective, I don't think a DSLR and your 600mm scope will provide the images that befit your goals... I may be wrong. After perusing the above article, you may agree.

We can, and will, help.

Respectfully and Clear Skies

As with most astrophotography, the equipment at the top of the pile costs serious money, going well into 5 figures. This is very true of solar narrowband imaging. I managed to use 'scopes up to 70mm but, at the time, only had a compact digital camera and not a DSLR, as today.

As the Sun is very quiet, I even question my sanity persisting with a Coronado PST. As I said in another post, budget does not always increase with experience.

[Hankmeister3]

My two cents. Great, spot-on advice on this thread. Always remember, you can never be complacent or reckless when viewing the Sun. Given the light gathering power of even a two-inch finder objective (much less 6, 8, 10, 12, 14 inch light buckets), you can destroy unprotected finder scopes (you HAVE to put a quality solar filter on your finder scope, too, or take off the finder), cameras, and your Mark 1 eyeballs. Personally, I use a Baader Planetarium glass solar filter on my 8-inch Celestron SCT which yields a very pleasant yellow-orange image. Then I can start thinking about introducing various bypass filters though personally I haven't done any serious imaging of the Sun because of the sheer lack of sunspots. That's just me. Of course full-on "solar telescopes" have already been factory prepped for solar work.

ALWAYS BE CAREFUL. ALWAYS TREAT A SUN VIEWING TELESCOPE LIKE A LOADED GUN. You only receive one set of eyeballs in a lifetime so even a quality $200 glass solar filter is NOT too much to spend to guarantee a lifetime of safely viewing Sol with either your eyes or your camera. It takes a fraction of a second to trash an unprotected camera because of lack of installing a quality solar filter on your 'scope. Though they are much cheaper, I've never been a fan of using aluminized mylar as a serious sun filter. I highly value my eyes and my "expensive" equipment so several hundred bucks is some pretty cheap insurance, plus the extra quality in the final image.

[Lowjiber]

Great advice, HankMeister. Caution is paramount when even thinking about turning any scope toward the sun.

I use four dedicated solar scopes, each has a Baader UV/IR-cut filter installed as the first thing the light encounters after entering the tube. Additionally, there is absolutely no need for a finder scope to even be attached, as a make-shift one can be made with two popsicle sticks. Each of my scopes is equipped with a Sol-Searcher (TeleVue).

I haven't visually observed the sun in over five years, as there is no need since I'm going to use a cam anyway... just another layer of safety.