[rtroxel]

I have attempted to observe Antares' companion star twice this month. Each time I've tried both OIII and UltraBlock filters. I'm thinking about blocking off part of an eyepiece with black tape, to cover Antares, but that would take the fun out of seeing the two stars together.

Any other solutions?

Thanks,

Roy

[Zeldaman2004]

I would think the filters would dim the companion too much, unless it's fairly bright?

What about using a cross hair eyepiece and placing the cross hair on the side of antares to try to add a little separation to them? It wouldn't be large enough to block the star, just a part of it.

I would also try going to insanely high magnifications.

[Capella85]

I believe I tried to split Antares once a number of years ago in my XT8, but I failed to pick out the companion star.

Something you could try is to build a hexagonal mask for your scope. There was an interesting article in the February 2008 issue of Sky & Telescope about how such a mask aids in seeing Sirius B (the "pup" star) next to the bright Sirius A. Apparently the hexagonal shape minimizes the glare around the bright star, thus enabling the faint companion star to emerge into view. I can expect such a setup would work just as well with Antares.

This post has been edited by Capella85: 21 June 2010 - 08:47 PM

[rtroxel]

Zeldaman2004, on 21 June 2010 - 09:06 PM, said:

I would think the filters would dim the companion too much, unless it's fairly bright?

What about using a cross hair eyepiece and placing the cross hair on the side of antares to try to add a little separation to them? It wouldn't be large enough to block the star, just a part of it.

I would also try going to insanely high magnifications.

I've read several places that an OIII filter brings out the companion star, although I don't know why it would. You also need very stable, clear skies, which can be difficult to find, since Antares is usually low on the southern horizon.

I'm sure high magnification helps, but that would also magnify any air turbulence or haze. Still, I'm going to keep trying - but not at BC .

This post has been edited by rtroxel: 22 June 2010 - 03:49 AM

[Bill Weir]

rtroxel, on 22 June 2010 - 02:48 AM, said:

I'm going to keep trying - but not at BC .

You're coming up to BC? Where?

The OIII can make the companion show up as green. I've seen the companion twice, both with my 12.5". An apodizing screen was used , not an OIII.

Bill

[rtroxel]

Bill Weir, on 22 June 2010 - 04:47 PM, said:

You're coming up to BC? Where?

The OIII can make the companion show up as green. I've seen the companion twice, both with my 12.5". An apodizing screen was used , not an OIII.

Bill

Do you mean British Columbia? Actually "BC" stands for Broad Creek, a local Boy Scout facility where my astronomy club observes.

[turbo-1]

As mentioned, a hexagonal mask can work wonders. It concentrates the Airey disk into 6 distinct spikes, so you can rotate the mask in order to position a close companion in a relatively dark zone so it will pop out. You can make it out of a piece of heavy black poster-board, so it's a very cheap accessory. Certainly, a whole lot more cost-effective than narrow-band filters.

[Bill Weir]

Those hexagonal masks work best with refractors, that's why I use an apodizing screen.

Bill

[turbo-1]

Bill Weir, on 22 June 2010 - 11:39 PM, said:

Those hexagonal masks work best with refractors, that's why I use an apodizing screen.

Bill

Yep. I'm just so used to using refractors now that I often fail to remember to account for secondary obstruction.

[FJAstronomy]

I had a crack at it last week, just for laughs. Needless to say, and entirely expected being at 50 North, all I saw was a smeary mess of Antares' colours being split up by the seeing, which was quite pretty.

This post has been edited by FJAstronomy: 21 July 2010 - 12:42 PM