Black hole

[Peter Ward]

Imaging from under the ever increasing light spill of Sydney is always a challenge. But I was curious to see how deep I could go with a modest exposure and reasonable seeing.

The answer seems to be magnitude 19.5.... as I managed to determine from this less imaged target (50% resolution to keep it web friendly)

It would be interesting to see what the result would be under a truly dark sky,
but I have a suspicion this is not too bad a result for an urban sky.

The link is here (http://www.atscope.com.au/BRO/gallery412.html)

[Atmos]

Although taken from skies with approx SQM of 21-21.5 depending on the night (I don’t have a meter but this is the range that others have measured), this hits about Mag 21. Significantly less aperture than 16” though ;)

PGC 9408 (www.astrobin.com/full/317234/0/)

For Sydney skies I have to say Mag 19.5 is pretty damn good.

[Peter Ward]

Thanks....but seems the link you supplied is broken :(

I can certainly reach Mag 21...but with mucho grande effort.... It would probably take me 8 hours and require good transparency. I was more curious about what an hour's worth would deliver.

[Atmos]

Fixed, not sure why but my phone refuses to put in the correct symbol :shrug:

You’ve got several times my light gathering power so an hour for you is like four hours for me and this has about four hours of luminance :)

[Peter Ward]

Ah...your link is mucho better. There are soooo many of these faint fuzzies.

I’ve taken pictures of dozens of them that simply are not catalogued...but when I asked the professionals as to whether I could lay claim to a “discovery” they answered, at Mag 21, unless they are interesting...meh! There are millions we haven’t listed...So what? :)

BTW....anyone else imaged this (somewhat drab looking ) eliptical galaxy?

[Atmos]

This is the ONLY amateur image of this region and it is by far the deepest. The only professional images are that of DSS and are limited at about Mag 19.5. I one night after fiddling with my scope I just decided to grab it and point it at the deepest darkest patch of sky that was going to go over zenith and went to bed. PGC 9408 just happened to randomly be near the centre of frame.

[Peter Ward]

I suspect our lines are crossed....I was referring to NGC 1407 as drab...as to PGC9408...well, yep, can't say I've seen that little sucker before :thumbsup:

Totally agree... at mag 20 and deeper, there is much to be explored.

[Star Catcher]

An interesting exercise Peter. Your location is actually very respectable given its proximity to the city.
Ted

[theodog]

From a post of mine on 23-05-2008;

http://www.iceinspace.com.au/forum/showthread.php?t=32167

"Two of the smaller members

Hi All,
Taken early last night.
Animation 4x10min +dark 12"

Upper right 1998 FO72 Mag 18.5
Lower middle 1994 PS10 Mag 20

*The Gif compression degraded the quality.* "

The images are 600 sec, and the asteroid in lower centre was mag 20.

Taken using a ST7e on a 12" GSO Newt on a Losmandy G11.
1 hour would be interesting:).

[Peter Ward]

Wow, that is remarkable.:thumbsup:

My skies are rubbish....but you can only work with what you've got.

That said I've found predicted minor planet magnitude estimates to be inaccurate, often way brighter (or dimmer) than the measured reality.

Seems I've also sold myself a little short, the posted image actually reached Mag 20 comfortably....but no way could I do that in 10 minutes at my location.

[Atmos]

You might just have to locate your scope 300km inland ;)

[Peter Ward]

You think it would help? Nah...I'd be at the mercy of our "worlds best practice NBN" :lol:



Thanks Ted.

[leon]

I don't really know what you two guys are one about, but i reckon that is a mighty fine effort Peter. :thumbsup:

Leon :thumbsup:

[Peter Ward]

:lol:

Indeed Leon, moaning about Mag 20 images from suburbia, complete with billion sun black holes.

This would the stuff of dreams when I was using hypered film, and CCD’s were only good for guiding being just half size of my little fingenail.

Today’s gear is just so awesome. :thumbsup:

[multiweb]

Looks good Peter. Pretty deep. :thumbsup: When did you get clear skies? :question: