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tilbrook@rbe.ne
07-03-2012, 05:56 PM
Hi,

The cloud finally cleared late monday night, so it gave me a chance to test out my orion mini guider package.

Fantastic peice if kit!!

I picked the tarantula becuase it's bright, and to test out the guider with something closer to the SCP. The image is cropped to take out coma, still need to get my spacing right. I now have it a spacing of 54mm, they say 53 to 55mm if it won't work with this final adjustment I thnk at has to be the corrector.

The image is quite blue from moonlight, and 5minute exposures, I think the background is about right ?

Telescope 8" f/4 astrograph.
HEQ pro 5 mount.
Camera Canon 1100D, plus not quite coma corrector.

10 x 5 minute subs.
9 darks.
9 flat.
9 bias.
Stacked in DSS.
Processed in Phtoshop.

Cheers,

Justin.

Lester
07-03-2012, 06:06 PM
Nice view Justin, showing the inner regions of this great nebula well. What ISO did you use? I'd be interested to see how much more you can get when the Moon leaves the sky.

All the best.

tilbrook@rbe.ne
07-03-2012, 06:18 PM
Thanks Lester,

Always forget to put the ISO, I used ISO 200 thought at 5 minutes any higher would be washed out in the moon light.

Cheers,

Justin.

Ross G
08-03-2012, 06:05 AM
A very nice shot Justin.

Great detail.

Ross.

mswhin63
08-03-2012, 11:44 AM
Nice job Justin, curious why Tarantula always seems blue/green, even mine turn out the same colour as yours.

Great tip on ISO, will try that as well.

alistairsam
08-03-2012, 01:02 PM
Hi Justin,

Looks good.
Did you try a shorter sub and higher ISO rather than a longer sub and lower ISO?
I'm guessing stacking 2 min subs at 800 ISO would provide good details as well and shouldn't look overexposed even with the moonlight.
would keep noise low as well. I'd say its worth a try to compare.
Did you find a reasonable amount of guide stars with the mini guider?
edit: my hunch is that with your dark skies and a the F4, the short sub will provide sufficient details at 400 or 800 since the object is bright.

tilbrook@rbe.ne
08-03-2012, 05:40 PM
Thanks Ross, Malcom and Alistair.


Hi Alistair,
The only reason I went for 5 minute subs was to try out the auto guiding. I tried at ISO 400 but in moonlight it washed out at 5 minutes.

Cheers,

Justin.