[Quicksand]

That looks pretty slick, Ex Finn. I think you do need that.

[Ex Finn.]

That looks pretty slick, Ex Finn. I think you do need that.

I know I "need it" and I really want it. The problem is that will I use it enough to justify the expense. Down deep, I am a cheap bastard.

[David]

My mother viewed the 1986 event from Hobart, Tasmania, Australia and was unimpressed saying "That it was better last time." viewed from country Western Australia !

Anyway it looks like this newcomer will be a northern hemisphere with just the tail visible south of the equator, or so local news advises,

[Nass]

Hmm, stacked short exposures, thanks for the tipoff. And I have a 200, a k5, I already stack ok and I have OGPS1 on its way. Cool!
Can I ask any reason not to use sigma 150-500?
Cheers

[p38arover]

Maybe not so easy to see for us in the Southern Hemisphere - unfortunately.

From the Sydney Observatory website:

......once the comet has made perihelion passage (perihelion is its closest point to the Sun), from the Southern Hemisphere it will be below the horizon both in the morning and evening sky. Our best chance to observe the comet with binoculars or the unaided eye is early in the morning before dawn in late November.

[steve1307]

Hmm, stacked short exposures, thanks for the tipoff. And I have a 200, a k5, I already stack ok and I have OGPS1 on its way. Cool!
Can I ask any reason not to use sigma 150-500?
Cheers

Well you can but the 150-500 is pretty slow f6.3 ? so you'll need a longer exposure to get enough light, compared to faster lens of course.

but.....

The astrotracer function can be used only for shorter durations with longer focal lengths as you reach the limits of the sensor's travel.
It depends on the FL and the declination (& i guess where you are pointing).

???GPS UNIT O-GPS1 | RICOH IMAGING - you may have to hit the google translate button

The tables at the bottom show the absolute maximum duration by FL (eg 50, 100 & 200mm) and declination (0, 45, 90degrees)
It only goes up to 200mm in the table so 500mm would be significantly less time. Any inaccuracy in the calculation/calibration is going to show up worse with a really long FL.

[Nass]

Thank you steve1307, just the sort of thing I was wondering about. Appreciated

[baro-nite]

Nothing much, but my first test of the Astrotracer function:




Although it is a good dark night (strong cold front just blew through), and this is about the darkest spot I can find near home, there's still plenty of light pollution -- couldn't really see M31 naked eye, for example. But I have a big trip coming up and will have better opportunities, hopefully to include Comet ISON, if it survives its approach to the sun. This is a single shot (other than the separate dark frame I took); I didn't get many good ones.

[Edit:] Different exposure (longer, wide open), and playing with the PP to bring out the nebulosity better: