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avandonk
15-09-2005, 01:21 AM
Here is a pic of the LMC from suburban Melbourne 85mm at f 2.8 211secX20
stacked with Registar.Taken 7-9-2005.Where did the red go.
iceman
15-09-2005, 06:09 AM
Very pretty shot, nicely done!

btw are you coming to the ballarat starcamp?
atalas
15-09-2005, 04:37 PM
Nice work avandonk !

Louie :thumbsup:
davidpretorius
15-09-2005, 04:42 PM
this is a great shot, i have been reading about this and i did not know it is a galaxy!
[1ponders]
15-09-2005, 04:44 PM
Its not an easy to drag the red out of avandonk. The ones I've tried have all ended up roughly the same colour as your. There's no denying you've got a great shot there though
asimov
15-09-2005, 06:52 PM
Very nice shot.
Striker
15-09-2005, 07:59 PM
Nice shot....what made you come up with "211 second x 20 exposures".....just curious
Itchy
15-09-2005, 10:43 PM
This is looking pretty good. What camera have you used?

Cheers
avandonk
16-09-2005, 11:04 AM
Canon 20D 85mm F1.8 at F2.8, with Hutech LPS-P2 LPR filter piggyback unguided on HEQ5.With this lens 3.5 minutes (211sec) exposure gets good detail without saturating the sensor.I've added a crop from the original stack to show the detail even with a focal length of 85mm.I am still learning what is possible with these digital systems.
Itchy
16-09-2005, 04:08 PM
Thanks. I am assuming that your 20D is unmodified. You asked "where did the red go?".

I asked the same question when I tried to shoot the Tarantula with my 300D. Unmodified cameras seem to miss all of the red on this object. Usually they can pick up a little and you can tease it out with processing. There must simply be not enough Ha there for the unmodified cameras to detect. Having said that I gave it a try anyway. The first link was my first attempt. As you can see No Red!

http://users.bigpond.net.au/itchysastro/tarantulaweb1.jpg

This one is from the same RAW's processed for red emphasis. Not much better really.

http://users.bigpond.net.au/itchysastro/taraLX.jpg

So I think if you want red on this object, then the IR filter needs to come out! :scared:

cheers
avandonk
17-09-2005, 02:16 PM
Yes,the sensitivity to H-alpha is down to about 20% to that of green say,on the 20D due to this filter.I have been tempted by the modifications Hutech do to Canons.
http://www.sciencecenter.net/hutech/canon/index.htm

The other way of course is to cheat and take exposures through a H-alpha filter for four to five times the exposure of the normal spectral response of the sensor and superimpose with Registar.

Next thing to try.

Bert