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View Full Version : Discussion: Astrophoto: North America Nebula ...



Fraser
2005-Jul-27, 07:21 PM
SUMMARY: Lorenzo Comolli took this beautiful picture of North America Nebula on the 16th of May 2002 in Capanne di Cosola, Italy. Lorenzo used a Pentax 75 apochromatic refractor with an exposure time of 45 minutes.

Do you have photos you'd like to share? Post them to the Universe Today astrophotography forum or email them to me directly, and I might feature one in Universe Today.

What do you think about this story? Post your comments below.

Eric Vaxxine
2005-Jul-28, 11:02 AM
Is that genuine red ? Or has it been filtered?

Ola D.
2005-Jul-28, 03:35 PM
Absolutely magnificent!

antoniseb
2005-Jul-28, 03:45 PM
Originally posted by Eric Vaxxine@Jul 28 2005, 11:02 AM
Is that genuine red ? Or has it been filtered?
It is a color photograph, and this cloud is red, which is expected color for a cloud of mostly Hydrogen. If you mean to ask how close is this red to what your eye would see? There are a lot of factors including the color balance of YOUR monitor.

Lorenzo Comolli
2005-Jul-29, 11:39 AM
Originally posted by Eric Vaxxine@Jul 28 2005, 11:02 AM
Is that genuine red ? Or has it been filtered?
Dear Eric,
that really a red nebula, no filters was used! The red emission is due to H-alpha line at 656.4nm.

Lorenzo

Astra
2005-Jul-30, 02:52 PM
I hate it when (almost always) astropics are filtered I want to now what celestial objects really look like.

Nereid
2005-Jul-30, 10:10 PM
Originally posted by Astra@Jul 30 2005, 02:52 PM
I hate it when (almost always) astropics are filtered I want to now what celestial objects really look like.
And how could we determine what 'really look like' means?

On the one hand, we could ask 'if all the light that my eyes/brain are capable of detecting were magnified 100/10,000/100million times, what would it 'look like'?' And a pretty good approximation to the answer would be 'look in a telescope which has an effective appeture that is 10/100/10,000 times that of your pupil' And you could do this (the Kecks/Geminis/VLT and maybe others will all give you a ~'10,000 times' experience).

On the other hand, we could ask 'if I were sufficiently close to {X} that my naked eye could register at least a 100:1 range of (optical) intensities. what would it 'look like'?' This would be trickier to answer, but I suspect that it would be hugely disappointing, if only because sufficiently close to get that range of intensities, the nebula would be spread across the whole sky, and so 'dilute' that the Milky Way (as seen from a good, dark southern hemisphere site) would be more impressive. :blink: :P

Astra
2005-Jul-30, 10:20 PM
B) Hey thanks for bursting my bubble! I think that sometimes a comparitive series of photographs would be interesting don't you? X Ray, visible spectrum ect. At the moment I'm just staring at the skies though.