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Neptune, Uranus, Saturn, Jupiter, Mars, Venus, Mercury, Moon & Earth
#1
I woke up at 2:00am on Friday morning 24th June and looked out of the bedroom window and saw that it was clear.  Smile In less than 1 hour, I had the car packed with camera gear and my Tak EM200 Mount and headed off to find skies a little darker than those of suburban Brisbane.

Just after 4:00am, after an 85 km drive, I found myself on the Esplanade at Toorbul and began to set up 100 metres or so from the car. It took me a while to figure out how everything fitted together again, then polar align and I was off. Smile

I fitted a Canon EOS R5 with RF 15-35mm F2.8L lens to the Mount and began a series of test shots and alighted on 30 secs, F5.6 at ISO1600. The lens promptly dewed up, so I went back to the car for the Pocket Powerbox Advance (PPBADV – USB & Power Hub) and a 12V DC SLA battery and fitted a dew heater, managing to plug the 12V DC IN to the IN Socket (physically it is a 2.1 mm DC input female socket, just like the 4 x 12V DC Power outlets and the Adjustable Out as well). Wouldn’t do to get this wrong in the dark…

Remarkably I had everything I needed as I didn’t have a plan as this was an impromptu decision to go for it, so I just began shooting using the built-in Interval Timer of the EOS R5.

I used the Focus Assist “Green Triangles” to manually focus, but when I checked again after a few shots, I noticed that the images were OOF – probably a result of the dew strap tugging on the lens, as it was fitted over the focus ring, as I had nowhere else to position it. Dodgy

Part way through the session, the PPBADV Blue LED began blinking so I went back to the car for the back up 12 VDC SLA and fitted that. I took this opportunity to point the camera up and grabbed a couple of shots towards the Zenith. Luckily, these came in use later as in those 3 images, I had also picked up Saturn. Sadly, Pluto was behind the trees by this stage.

PixInsight did a fantastic job of aligning and stacking the disorganized, chaotic set of files I emptied into it, although I had to manually blend in those lucky shots of Saturn in PS CC.

I have included crops of each target to provide some more detail on these regions.

How do you explain to Clyde William Tombaugh (discoverer of Pluto in 1930) that using modern equipment, I recorded the position of Pluto with a 15mm wide angle lens and a single 30 sec exposure… Rolleyes


Cheers

Dennis


   

   
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#2
Wow Dennis you do nice work when the weather cooperates! Most impressive! My wife went out to see the planets this morning, but only spotted 3 + the moon from our front porch.

I think Clyde would say that reciprocity failure's a killer. Plus 103Oa plates were pretty slow (I think those were the standard astronomical blue sensitive plates back then - maybe not that good). Digital sensors crush film these days.

Phil S.
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#3
Outstanding work Dennis. Thanks so much for your dedication and having it all together and sharing.
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#4
Thanks Phil and BMD, I appreciate you looking and commenting. Smile

I have attached the 30 sec test shot which I took after I had arrived and set up, just randomly pointing towards the Zenith to check all was okay.

It was taken at 15mm focal length with the Canon RF 15-35mm F2.8L IS USM lens, where I later discovered I had recorded Pluto. The region is right at the edge of the frame so suffers from distortion which did improve somewhat when stopped down to F5.6 compared to wide open at F2.8.

Cheers

Dennis

EDIT: The dew strap can bee seen at bottom right, a good reason to take test shots.

   
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#5
Wow, I'm really surprised that you could capture Pluto in 30 seconds using a 15 mm aperture. It's currently 14.3 magnitude according to my ST4v. I guess it helps to be in the southern hemisphere for Pluto these days.

Awsome.

Phil S.
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#6
(2022-06-27, 12:05 AM)PMSchu Wrote: Wow, I'm really surprised that you could capture Pluto in 30 seconds using a 15 mm aperture. It's currently 14.3 magnitude according to my ST4v. I guess it helps to be in the southern hemisphere for Pluto these days.

Awsome.

Phil S.

Hi Phil

Thanks for the feedback - I'll double check as it is so easy to see what you want to see. Smile

Cheers

Dennis

UPDATE:
Sigh, you're correct Phil, I hadn't zoomed in enough on the star field and when I did, Pluto popped out from the star Tycho 6892:511 which is mag 8. I think the 15mm lens, 30 secs at ISO 1600 managed to record down to mag 10, so no Pluto for me. Sad

The other brighter star in the circle is HIP 98575 at mag 6.

Thanks and good pick up, Clyde can rest easily now. Smile

Cheers

Dennis
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#7
Hi Dennis,

Magnitude 10 in 30 sec using a 15 mm aperture is still pretty amazing isn't it? You need ~50x more photons to catch Pluto then. Clyde would probably sacrifice a body part for today's technology Smile .

One nice thing about Pluto, he doesn't move very fast & now you know where he's hiding. After you get some sleep, he better be careful.

I think Makemake is within range of your system too BTW.

Phil S.
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#8
Thanks Phil, it is quite sobering to see the math's behind this. Smile

You also save me the embarrassment of sending my results to the Nobel Prize Organisation to gain global recognition for this feat of astrophotography. Dodgy

Cheers

Dennis
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#9
Oh man, don't even go there! While my friend Dan Grieser & I were using the 16" Schmidt camera at Perkins Observatory, Dan found a small object on one of the plates. We wondered if it was a comet, so we asked if anyone could confirm if there was something there. A comet hunter in California, whose name I can't remember, checked & found nothing. The astronomers at OSU were unhappy with us & sent the Schmidt camera out west for Gene Shoemaker & David Levy to use in their comet hunting.

Dan figured that we'd caught a faint head-on meteor because the object had a short tail like a faint comet. Interesting times  Big Grin.

You don't want to tick those folks off!

Phil S.
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#10
Nobel or not, you got my vote. Thanks for sharing those pics Smile
Win11 Pro, 64gb ddr4 Ram, RTX 2080 Super, i7 11700K, 3 x 1920x1080 280hz Monitors.
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