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alpal
25-02-2012, 01:50 PM
I spent a night on Mt Baw Baw - 2.5 hours drive from my place in Melbourne.
5,000 feet in altitude - the sky was the best I've ever seen
but the wind came up - and buffeted my telescope.
The result was that most sub-frames had to be deleted.


I managed to get only 5 resonable frames of Eta Carinae -
each was 2.5 minutes &
6 x 5 minute sub-frames of M83 - the Southern Pinwheel
all at ISO 1600.
Telescope 8" f6 Newt, EQ6 Pro modified mount, Baader MPCC,
no filters with an unmodified Canon EOS 1000d.
PHD guiding, Dither Master from Nicola with Canon remote shooting.

I only did a minimum of processing.

A larger version of Eta Carinae is here:
http://i262.photobucket.com/albums/ii119/alpal2002/EtaCarinae5frames_DSS_PS_PS_PS.jpg

astronobob
25-02-2012, 02:43 PM
A Good nights work @ 5000ft, Great amount of light collected in both, envious of the location, the bigest hills in SEQ is about 1300ft : (
M83 looks mighty fine , tho I am bias toward galaxies : ) both great !

Mighty_oz
25-02-2012, 02:53 PM
You've got to be happy with those ones :)
Dedication plus for going so far as well. A wind shield next time hey.

alpal
25-02-2012, 09:30 PM
Thanks guys.
The trip to Mt Baw Baw was worth it just for the view.
This was a photo just with my camera from a previous visit.

http://i262.photobucket.com/albums/ii119/alpal2002/SouthernCrossabovetreesatBawBawmedi umsize.jpg

That's only a glimpse of what it looks like.
The true view is far more breath taking.
Pity we can't see it like that from our big cities.

alpal
26-02-2012, 08:11 AM
I don’t know of any place with a fair bit of altitude & sheltered.
You’d need a portable tent to protect the telescope on Baw Baw but as I image
from the car park there is no way to fix it to the road surface.
The wind gusts were making the lid of my laptop flap back & forward – it was that strong!
A tent would blow away like a kite.

Out of 4 times I've been to Baw Baw only 1 time had no wind.
What a pity as at that altitude you get the best seeing.
Example:
When I first got my telescope I thought there was something wrong with it.
I looked at Jupiter on about 6 occasions from Melbourne & all
I could see was a fuzzy ball with 2 lines going through it.
From Mt Baw Baw - Jupiter just snapped into view - I have
never seen it look like that - it was sharp & clear.
I could go to over 300 x magnification easily on Baw Baw.

5,000 feet up makes a huge difference!

alpal
27-02-2012, 01:26 AM
I had 2 other photos each of only 2.5 minutes at ISO 1600
that I also took to one side of the Eta Carinae Nebula.
I combined them in a mosaic to get a larger picture.
They are all just single shots - no stacking.
Shows you the good signal to noise ratio at a dark site
with a bright target.
You can still see the join in the photo which
I will later try to remove.
I used Louie's ideas for star repair from his video
& also Fitswork 4.
Looks like I ended up with a nice wide mosaic &
I suppose I could add the left had side another time?

A larger version is here:
http://i262.photobucket.com/albums/ii119/alpal2002/Eta_mosaic_3frames_m.jpg

multiweb
27-02-2012, 06:08 AM
Very nice shots considering the adverse conditions. Well done. :thumbsup:

strongmanmike
27-02-2012, 01:22 PM
Wind bluudy wind :mad2:

When it is gusting is the worst, steady breezes aren't too bad.

The actual keyhole area looks really good with a nice variation in colour and some depth to it, nice job. M83 looks a bit over processed though and you may have lost some data there I think..?

Man that sky looks good and that is a good skyscape shot of it too!

Mike

alpal
27-02-2012, 10:25 PM
Good advice Mike.
The sky at Mt Baw Baw is something you can never forget -
it's a life changing experience to see the Milky Way so bright.
Do you like this version of M83 better?
There is only so much I can do with wind affected data.
I did a lot of star repair as per Louie's videos.

Ross G
01-03-2012, 07:00 PM
Very good photos Allan.

I really like your M83.

Your dark site sounds amazing. You are so lucky to have it so close to you.

Thanks.

Ross.

alpal
02-03-2012, 10:34 PM
Thanks Ross,
I think I did well to get what little I did from that night.
I know I'll go to Mt Baw Baw again.
Maybe if I can get a better idea of the wind forcast I'll do better.
The first photo I posted on this thread of Eta Carinae could
be improved with some more processing.

did you see the larger size?
http://i262.photobucket.com/albums/ii119/alpal2002/EtaCarinae5frames_DSS_PS_PS_PS.jpg

Only 5 frames stacked gave me a grey/blue true colour
that I haven't seen on other photos.
Everyone else has all red.
If I could tidy the star sizes up in PS I could really make it much better.
5 stacked photos from Baw Baw is worth more than 50 from the city
even on bright targets.

Ross G
03-03-2012, 07:32 AM
Hi Allan,

The larger version looks very good. Your tracking, focus etc looks spot on to me. I wish I could stars like that from my Vixen 8".

I am no expert but I think the bluer colour is a product of your unmodded camera. When I moved from an unmodded 350D to a modded one I saw a huge increase the amount of red in many of my photos, including Eta C.

You are right about a good dark site.
We have a place we go to called Coonabarabran. It is about 6 to 7 hours driving west of Sydney. We might only get there 3 or 4 times a year but it's worth it.

Good luck.

Ross.

alpal
03-03-2012, 08:12 AM
Thanks Ross,
I like the blue colour.
I think the unmodded camera is giving me the correct natural colours.
The stars could be a lot better - they are elongated from the guiding.
Ha comes out all red & in some ways wrecks the colour balance - in my opinion.
The PHD guiding graph is normally within +/- one division but
at times due to wind it would go off scale.
I know how to fix the stars using photoshop in that photo.

Before I had guiding there was one night out of 4 on Mt Baw Baw
where there was no wind.
If I can get another night like that I'll pull in some big fish!
Another thing - it always gets cold on Mt Baw Baw.
That's good for my camera to reduce noise.

alpal
05-03-2012, 11:01 PM
Hi Everyone,
I finally got the time to process the original Eta Carinae with 5 frames stacked.
It has 21 iterations.
I did a lot of work fixing up stars using Louie's techniques
+/1 pixel back & forward. I Also used Fitswork4 to make stars smaller.
I used "digging out the details" by Ken Crawford to further stretch
various areas on the frame by using vector masks from a darker layer.
The keyhole nebula managed to even have a slight yellow section
& definetely a red part which streams off.
I turned up the blue slightly to emphasize the fact that the
unmodded camera with no filter at a dark site is picking up
a lot of the blue spectrum - whereas most pictures
of Eta - published are nearly all red.

This picture is just over 1 MByte & is 2143 x 1428 pixels.
Press F11 to get a full screen & ctrl + or - to change the size.
Press F11 again to return to a normal screen.

Picture here:
http://i262.photobucket.com/albums/ii119/alpal2002/EtaCarinae5frames_DSS_PS_PS_PS_21.j pg

alpal
11-03-2012, 03:50 AM
I just re-processed the mosaic.
I think it looks not too bad - basically 3 frames overlapping.
I had to do a lot of star repair - but anyway:

http://i262.photobucket.com/albums/ii119/alpal2002/Eta_mosaic_3frames_a_10thMarch2012_ h_4-1.jpg

Ross G
14-03-2012, 09:02 PM
Hi Allan,

Looks great.

You are acquiring some very good skills.

Keep it coming.


Ross.

alpal
14-03-2012, 09:21 PM
Thanks Ross,
I know it will all come together one night
& there will be an improvement.

ChrisM
14-03-2012, 09:29 PM
Allan, your latest repro looks great! The variety of colour makes it more interesting.

I think that it's hard to say what is correct colour because we don't actually see it live - we see just the photographic results.

I remember bivvying out on the side of the Baw Baw Plateau (up the other end near Mt St Gwinear) at a bit below 5,000' one night when I took the kids camping there, and the sky was fantastic. Not sure that I slept a lot that night; just lay back and admired the heavens!

Another time, I drove to the top of Mt McKay (out the back of Falls Creek) at 6,025' to photograph the night sky, but the wind was so strong that I thought my car was going to be blown off the mountain. No pics that night.

Anyway - well done.
Chris

alpal
14-03-2012, 10:00 PM
Thanks Chris,
I didn't know there was a higher point at 6,025 feet.
The wind is the problem at these altitudes.
I've had only one night out of 4 without high winds
at some stage of the night on Baw Baw .
Wouldn't it be great if there was an empty observatory
on top of Baw Baw or Mt McKay where you could place your telescope?

I really think our high peaks are too under developed for astronomy.
I wonder if it's because the National Parks Govt. agencies think
that observatories look ugly in those pristine environments?

Each time I've looked at the sky from Baw Baw I was
simply overcome at how bright the Milky Way &
the rest of the sky looked.
I feel sad for city dwellers & most people I know
who've never seen the sky like that.

ChrisM
16-03-2012, 06:54 PM
Allan,

Mt McKay is in a different part of Victoria to Mt Baw Baw. It's about 4 km by road from Falls Creek village on the Bogong High Plains. There are plenty of other spots up there that would provide more shelter, too.

I've attached a couple of pics I took over 30 years ago of Mt McKay. It has a fire lookout tower plus a communications tower on top, as well as a small public shelter. Unless you're on skis or similar, there isn't any access in winter.

Having an observatory above the snowline might present a few more challenges too (although plenty do it).

Chris

alpal
16-03-2012, 08:46 PM
Hi Chris,
Yes the highest peak is Mount Bogong:

http://en.wikipedia.org/wiki/Mount_Bogong

at 6043 feet but it doesn't have a car park at the top as far as I can see.

Yes I agree & people do great work at sub -zero temperatures in the Northern hemisphere.
Look at the Cloudy Nights forum.
A DSLR camera works really well at those temps.
I think the noise doubles every 7 degrees in temp for my Canon EOS 1000d.

Mt McKay is too far away for me when I can get nearly 5,000 feet
at Baw Baw with only 2.5 hours drive.
As you're in Gippsland maybe you can image on Baw Baw too?

I am surprised that no one has managed to put an observatory on Mt Baw Baw.
You'd think the Govt. or a private company would build a whole lot
of them there for astronomers - I mean empty ones so that
they could be hired out - it would even encourage astronomy tourism.
Some people have high end portable systems costing $40 grand or more.
I am sure they would dearly love to image from altitude.
I call it "getting your money's worth" out of your equipment.

The number of clear days has been too low in the last
3 years on Baw Baw but it will come good eventually.