When Will it End?

[AdamJL]

I'm glad that the country hasn't suffered the fires of a couple of years ago this summer. That's the most important thing.

But when will these clouds vanish? At a lovely B2 site now and the gods are teasing me with the weather.

Maybe I should go back to wildlife and landscape photography for a while

Trouble is I can't fit anything else in the car if I take the astro gear for a trip away!

I'm shooting clouds here, but not the space ones... at least the view is nice :)

[Zuts]

You need to pick the right place, I drove 1,200 km to Broken Hill over Christmas. it was the only place in N.S.W that wasn't raining...

[mura_gadi]

6-8 weeks with any luck.

The main La Nina drives are fluctuating or on the downturn, except for SAM.

Condition could return to neutral early Autumn, the SAM index needs to drop a little, but generally, the major indicators are favourable for a return to drier conditions by end of March.

(SAM is a major influence on east coast rain/cloud though...)


http://www.bom.gov.au/climate/enso/index.shtml

[AdamJL]

I love this hobby, but not that much just yet :D
That said, 3 hours out of Sydney with good weather and you're in B1-B2 skies. Here's hoping it will all get better come March



Good info, thanks! Should be perfect timing for Dragons of Ara season as well.

[OzEclipse]

My dark sky property is out near Young on the border between B1/B2 zones. Bortle is a moveable rating. The actual Bortle sky rating depends critically upon air transparency and transparency is especially important when you want to do anything at lower altitudes nearer the horizon. The low altitude skies, especially to the north are free of any light pollution so low altitude far north subjects come into play albeit not as good as shooting from the northern hemisphere where they are high overhead.

When the air is clear, this place is a B1 and better than skies I saw in the Atacama desert in Chile at 4800m altitude where the air is always full of dust blown off the desert. They put telescopes up there to get above the water vapour and transparency for the IR.

When the air out here is full of pollen or dust, my sky drops to a 2 or 3. Thick smoke probably drops it to a 4 or 5 depending how bad the smoke is. But when it's clear, it's sensational. The ECMWF model is extremely accurate out here so you can really plan ahead.

Once you get off the ranges out west onto the SW slopes, the summer skies become very clear and skies the rest of the year are clearer. I have lived in Canberra for the past 37 years. Canberra and all the mountains around it is just a big cloud bowl compared to out here in the Central West. Dare I say, I have too much clear sky. Unless I go to full automation, I can't really use all the clear nights.

I have owned this property since late October 2020. I have only had complete new Moon wash outs in March, June, and October of 2021. There was a new Moon around September 7, 2021. Between last qtr at the end of August and first quarter on Sept 14, I had 12/14 of the nights perfectly clear and many with stunning transparency.

Last week, I had 2 clear nights, Fri, Sat, and tonight clear, and this coming week another 3 clear nights. We have had moderate winds gusting to 20km/hr for the past few days. Consistent wind is unusual out here. We get big blows with storms but it's usually pretty still when the skies are clear. This is the first time I've seen it like this. Doesn't stop the observing, I just have to set up in a sheltered spot.

You don't need to go to Broken Hill, and Broken Hill wasn't the only place where it wasn't raining. During the 21 days from Dec 19-Jan 9 when comet Leonard was putting on the big show, I had 15/21 perfectly clear nights and 1 partly cloudy night when late twilight was clear then thin cloud came in. Even so, I was still able to shoot the comet through thin cloud. But I know from friends that south east of here Canberra and through to the coast, it was cloudy night after night and a few friends came out here to get a clear run at Comet Leonard and it's beautiful 10-20 degree tail.

Comet Leonard Gallery: https://joe-cali.com/astronomy/astrophotography-2/index9.html

Keep calm and carry on! ;)

Cheers

Joe

[Zuts]

Sounds nice, I left Sydney on the 4th of January, it was raining west of Cobar and cloudy until Wilcannia. Broken Hill was completely clear for my 5 nights there

The previous summer I went to Ivanhoe, but this time that was wet as well. Ivanhoe was better though as I sometimes stay in Airbnb's rather than camp and Ivanhoe is certainly darker than Broken Hill. If anyone goes to Broken Hill there is a lookout about 20km north of Silverton. It's flat and a couple of hundred feet above the plain, and around 50 km from Broken Hill so there is basically zero light pollution. However you need to setup and tear down every night, unless you want to be stuck in a tent at 45 degrees in the morning...

Paul

[frank777]

I've decided to take up meteorology... at least there'd always be something to look at.

[Zuts]

:rofl:

Not in Darwin, I lived there for 10 years. During the dry everything is the same each day, clear sky, 20 to 30 min/max. Best weather but mereologically a bit boring.

Now if we are talking about the wet, enough lightning and storms to keep everyone happy, except astronomers...

Cheers
Paul

[OzEclipse]

Hi Paul,

Yes there were 3 days of cloud on Jan 6,7, 8. The last two images in my Leonard sequence has images taken on Jan 5 & Jan 9. Cloudy/rainy on the 3 nights in between. However, your original post stated "over Christmas," when most nights were clear.

Before buying out here, I use to observe and photograph from a friends B2 property 50 mins drive Canberra. Had to set up and pull down every night.

In 2018, I developed a very simple fast and accurate polar alignment technique. It requires a laser aligning device which I built for about $30. It only takes me 4 mins to precise polar align. If the mount shifts during the night, a bump or sinking into soft ground, it only takes another minute or two to recheck the alignment. No computers, cameras, plate solving, or networks required.

Joe

[AstralTraveller]

Package them up and sell them. :)

[strongmanmike]

Sounds like a reeeally wonderful spot you have there Joe, be nice to visit one day :thumbsup:



This period was stunning up at Eagleview too, lots of clear nights with super transparency and high contrast, as you say, right down to the horizon. I could still see one of the stars inside the Coalsack when it was sitting at its lowest point on the southern horizon! Calibrated SQM readings were hitting 22 and regularly in the mid to high 21.90's, had incredible views of Jupiter and Saturn and being able to max out my 12" Dob with the highest magnifications possible (750X) on many nights was great, even revealing the Enche division in Saturns rings a few times. Under such conditions the sky is utterly breathtaking huh? :thumbsup: Apart from being able to see the rare Gegenschein and even rarer Zodiacal bridge, the most incredible feature I will remember is the enormous breadth of the Milky Way overhead, it was massively wide, the very faint outer gossamer glow that extends to the East and West from the usual dark sky bulge, seemed to extend for ever, it was just amazing :)

Looking forward to the easing of Ms Nina though :rolleyes: :scared:

Mike

[strongmanmike]

Great looking spot there Adam :thumbsup:

Mike

[PaulSthcoast]

Hi Joe,

Care to 'shed some light' onto the Polar Alignment tool ?

I'm sure I am.not the only one who is curious about it.

Young...
I have spent quite a bit if time out that way.

Brings back many many memories.

Thanks.

Paul.

[OzEclipse]

Sure, there's a whole article about it on my website.
https://joe-cali.com/ Go to the bottom of the home page and look for the article on APPS. APPS stands for Artificial Projected Pole Star. It's simple, quick and cost me $30 to build 4 years ago. I can usually do a precise align in about 4mins and then don't need to do any dec corrections in 3 min subs at 1300mm focal length. I've been using it since 2018 and it's never failed me. The only problems I have affect any method of polar alignment, tripod legs sometimes settling into soft ground during the night. I leave the laser in place turned off. Then it only takes a couple of mins to re-check and re-align the polar alignment during the night. This only occurs when the ground is saturated and wet.

Joe

[Startrek]

I’m also interested in your polar alignment method too
With no computers or cameras how do you measure your polar alignment error ( drift time and laser
angle ) ??
I’m assuming within 4 minutes your under an arc minute ?

Curious !!

Thanks

[OzEclipse]

Hi Martin,
I don't measure the PA error so I can't tell you how many minutes of error I have. As you note, with no computers or cameras I can't measure polar alignment error.

Over a couple of hours of subs, I'll see dec drift but not within a sub.

The attached diagram shows the three stars I use. The little circle is 1 arc minute radius. It's not hard to get pointed somewhere around or just over 1 min using this method.

The trick is to keep parallax small by keeping the polar axis & optical axis of finder very close to the laser beam and the binocular line of vision. Working at home, I place the laser on a tripod right in front and almost in line with the PA and I stand just in front of the laser and have it shoot past my ear. I often use 7x35 German binos. The 8.9 mag star is a little hard to see but I can use the two brighter stars. This is fine when shooting with 135 f2 or 300 f4 lenses. For the prime focus, I'll use my 9x63mm Orion's and use all three stars. I have a tripod mount for them.

There is no graticule so the accuracy does depend on your visual geometry ability with the two stars and of course, how accurate the polar finder is aligned to the polar axis. It works for me, in particular because I use a DSLR driven by an intervalometer, setting up a computer and camera is all extra work, extra wiring etc. I also used to work from an unpowered site with lots of dew so I started working this way to be able to work all night off a small 7AH SLA battery or a small car battery if running dew heaters. Now, although I have AC power in my backyard I have continued working the same simple way.

If you use an ASI air, Sharpcap or similar and have to set up computer and camera anyway, then the time & trouble saving is somewhat less than for me. I can look outside at midnight, see clouds have cleared. I can be set up and PA'd in about 30 mins shooting soon after. My DSLR runs for about 5-6 hrs on one battery, intervalometer batteries last many nights and if I don't slew much, can run most of a night on one 7AH SLA.

I'm not trying to sell these to anyone. The design is so simple, patenting would be a waste of time so I put details on my website for anyone to use. You can build one without a lathe or any machining. You could make one with glued and sanded dressed wood and use Danish wax, candle wax or soap between the surfaces to lube the wooden bearing surfaces. The key is that those surfaces need to slide smooth and stop where you leave them so you can point accurately.

Feel free to PM me if you want to build one and have any specific Q's.

Joe

[AdamJL]

not sure this is going to end anytime soon:



https://www.smh.com.au/environment/weather/temperature-drops-sharply-as-sydney-says-icy-farewell-to-autumn-20220530-p5apkn.html

[xelasnave]

Don't worry..given the amount of rain that has fallen there can't be much left up there:P

-New astro shot details..of the future.. 200 subs each of 2 seconds at 35000 ISO during a 5 minute clear sky.

Alex

[Startrek]

Saturday night in Sydney was clear and last night was clear too with less dew and no moon around , conditions were excellent up to mid night
South Coast NSW was clear too
The mid to south east coast has had some clear nights through May which Ive taken full advantage.
Tuesday and Wednesday nights are clear too but windy ( 25 to 30 km /hr ) with low humidity. I’m going to rig up a tarp behind my rig and give it a shot.

I’m sure the worst is behind us ( at least on the mid to south NSW east coast )

[OzEclipse]

:rofl::rofl:
Check your math Alex. You can only do 150 subs in 5 mins. Hope your weather improves soon.

[xelasnave]

Armed with that information I can make a huge improvement in my work flow;)

Alex

[AdamJL]

Looks like a high chance of another La Nina developing soon.
See you in 12 months

https://www.news.com.au/technology/environment/first-signs-of-triple-la-nina-emerge-negative-indian-ocean-dipole-to-bring-extra-rain/news-story/f6f498a69e2c1406d286dd142b8247db