Rcw105

[EddieT]

Hello to all,
I thought some of you might be interested in seeing some of the Ha images I've been doing lately of southern emission regions.
Starting with RCW105 a very interesting area in Norma.

[rumples riot]

Nice stuff, the region really comes alive under Ha imaging.

Keep them coming.

[Rodstar]

Nice image Eddie. Does that area have an NGC #?

[[1ponders]]

Your really tempting me Eddie to get the IR filter removed from my 300D and get a Ha filter. That's a great shot.

[iceman]

Very nice! Are you going to combine it with some RGB exposures?

I just love the long exposure HaRGB stuff that Suk Lee and others do.. your image is superb.

[EddieT]

Rod,
This object doesn't have an NGC number. It's one of our mysterious nary-seen southern gems. I only discovered it from my Milky Way mosaic which I'm using to pick areas of interest from. It's a sort-off backward discovery mission for me :)

Also known as Gum51 and located at RA: 16h10m0.0s Dec: -49°08'00", this is not a very bright object.

This exposure is 7.5 hours taken over three nights and the field covers 56 x 38 arcminutes.

[EddieT]

Paul (R), I've been very tempted to get one of the later digital cameras. I have a Sony DSC-P1 (3.3MP) but back when I bought it a camera with manual exposure settings was about $70k! Needless to say it's not really useful for astrophotography.

[EddieT]

Mike, Yes I have done a HaRGB of this one. Total exposure time was 9.5 hours. Here you go.

[[1ponders]]

:jawdrop:

[iceman]

Just georgeous Eddie! Is it visible at all through a telescope? Do you need any UHC/OIII filters for it?

[EddieT]

It's a HII region so a Ha/Hb (maybe Red) filter would help, but I've never visually attempted it so I can't say. Optical emission line fluxes of these (RCW/Gum) objects are also hard to come by so I cannot give you an estimate. Based on my data I would say it would at least be "very hard".

All you can do is try I suppose it shouldn't be hard too to locate being within the main formation of stars in Norma.

My Milky Way Map may help you http://astroshed.com/milkymap.html

It's object number 12 in Norma.

[ving]

man do you do some long exposures!
gret pics eddie! :)

[EddieT]

Thanks Ving. I'm not in the best place for astrophotography so long exposures are needed to cut through the light pollution and average out the mediocre seeing.

[h0ughy]

They are absolutely fantastic images. You have definetly got everything spot on in the tin shed!

[EddieT]

Thanks Houghy, it took some months and quite a bit of tweaking but the new system is finally working well.

[rumples riot]

Yes I like the colour image much better. Nice detail and very sharp. Good stuff Eddie.

[EddieT]

Thanks Paul, I prefer the colour version too. It tends to bring out more contrast.

[tornado33]

Yes great shot. Speaking of RCW objects heres one two down from yours, RCW 103
http://www.users.on.net/~josiah/temp/rcw103small.jpg
taken last year. Its just a stack of two 5 min shots with 300d and 10 inch f5.6 scope
Scott

[EddieT]

Good one Scott. These RCW regions are dim suckers aren't they!

[xelasnave]

I am totally impressed with your work Eddie.. brillant stuff. Mate if you ever want to work out of a dark site just call by, I would love to see how you would go in a better site... or have you taken it as far as possible with your current work? I have a 300d and a couple of scopes could you please tell me what one has to do to set up for ha work.. I have no idea
alex

[EddieT]

Thanks Alex, I'm glad to be able to give these images an appreciative audience!

As for dark skies, Ha rejects all but a narrow bandwidth so darker skies won't benefit the images all that much. The RGB components would benefit by requiring shorter exposures, but not much in any other way so imaging is a good viewing alternative for people who live under bright skies. But thanks so much for the offer, I do appreciate it.

Once a year I take my entire setup to Esk for 7 days and nights. This is a half day tear-down and setup so I don't like to do that too often. My main reasons for going to astrofest are not so much the darker skies, but the different aspect; i.e. I can position the setup for targets I can't see from my backyard. And of course the social aspect of catching up with friends I only see once a year.

I'm not really up to speed with digital cameras these days, but I get more and more impressed with their capabilities as the years pass. I think the biggest obstacle is with the IR filters installed in them for daylight use. If yours is one of the Astronomy versions without the IR-blocking filter, then you may well be able to take good Ha images with them. You will need a Ha filter and some way of mounting it between the camera and telescope. There are various flavours of deep sky Ha filters around, but you are probably best to get one with a wider passband. Mine is 10nm, there are others around that are 3nm (most of the stars will simply disappear and exposures will need to be very long) and up to 15nm, allowing more light around the Ha band to pass through. Unless doing extreme Ha data analysis, the wider filters are the way to go.