Uranus and moons; Titania, Umbriel, Oberon & Ariel

[Dennis]

Hello,

After having a look at Jupiter last night (30/31 Aug 2008) I slewed to Uranus just after midnight and grabbed 30 x 15 sec exposures using a TeleVue x4 PowerMate in the Mewlon 180 F12, delivering an effective focal ratio of F48 (8640mm fl).

I also managed to grab an RGB set and have tried to blend the RGB with the Luminance to reveal a hint of colour. The moons were not visible on the RGB frames so they remain B&W in the composite.

The session was marred a little by thin clouds and occasional strong gusts but overall, I had a good time and was quite pleased with the outcome. I have included a screen print from SkyTools (http://www.skyhound.com/cs.html), a very rich observation planning and charting application. Oberon and Ariel were 2 arc sec apart at the time of capture. Oh the things we do for fun!:lol:

Cheers

Dennis

[sheeny]

Very cool, Dennis!

Al.

[AlexN]

great resolution! Really shows the quality of the setup.

[Matty P]

Awesome result Dennis, amazing detail and clarity.

You have inspired me to give it another go after my last attempt.

Well done. :)

[Striker]

Wow very impresive Dennis.

Love the presentation as well.

[war bird]

great stuff

[Dennis]

Thanks guys, I had heaps of fun planning for this, finally finding a night when conditions were reasonable, with 5 to 6/10 seeing. I thought at one stage that an F-111 from Amberley (on its way to RiverFire) might fly through the field to add some drama! LOL!

I’ve also just updated the image to include the following details:

FOV is approx 1.7x2.3 arcmin
Image scale is approx 0.2 arcsec/pixel

Cheers

Dennis

[AlexN]

:eyepop: 0.2 arcsec/pixel!! Crrraaazzzzyy!!!!

I'll be picking your noggin for tips on this kind of imaging soon enough Dennis... :) You've been warned :D

[Dennis]

LOL! As a validation test, I counted 10 pixels between the moons Oberon and Ariel, which when multiplied by 0.2 arcsec/pixel, nicely gives the expected results of their 2 arcsec separation as indicated by SkyTools.

Cheers

Dennis

[StephenM]

Great image Dennis! Very impressive.

Cheers,
Stephen

[Ric]

Lovely capture Dennis and to bag three of it's moons as well, well done.

[Dennis]

Here is a single, 15 second raw frame showing more or less how the image appeared on screen at the time of capture.

Cheers

Dennis

[iceman]

Beautiful, inspiring result. I love it when you do these type of images.

More than just a pretty picture!

[h0ughy]

You’re a very talented and clever man Mr Simmons!! Brilliant result!!

[RB]

Excellent capture Dennis, fantastic work and I love the presentation too.

:thumbsup:

[drmorbius]

Very nice Dennis, well done!

[Dennis]

Thank you for all your nice comments.

Sadly, I have been relegated to the far reaches of our solar system, as the local seeing for this Jupiter season just has not come up to the amazing quality we Brisbanites experienced a couple of seasons ago.

Cheers

Dennis

[AlexN]

oh come on Dennis.. Its not great, but its not THAAAAT bad...

[Dennis]

Hey Alex

A couple of seasons ago, the seeing was soooo good that I almost didn’t need to process the AVI’s in Registax, the detail was popping out on individual frames!:eyepop:

It’s such a pity that then, I was using the ToUcam and still at the beginning of my planetary imaging apprenticeship. Nowadays, I don’t even bother getting out of bed unless it’s at least 7 or 8/10!:P

Cheers

Dennis

[AlexN]

Yeah.. I've heard that from a few people now... Im still in the fairly infantile stages of my planetary imaging, so any chance I get im out... even if the seeing is average, its still good practice..

[Dennis]

I feel most sorry for Matt, who suffered awful seeing conditions in Canberra when it was hitting 9/10 in Brissie. Since the poor fellow relocated to Brissie, it’s been an awful period of seeing, not to mention fewer nights on which to even consider dragging the gear outside!

Cheers

Dennis

[AlexN]

You feel sorry for him??? MATT IS TO BLAME FOR OUR SEEING!! He brought it with him from A.C.T.!!

[matt]

Ahhhhh.

Yes...I remember your images from that period, Dennis, and recall thinking to myself 'Wow!!! I gotta hi-tail it to Brizzy":lol:

As you say, no such luck this apparition.

But nice work on Uranus and the moons:thumbsup:

Dennis, you've inspired me to have a crack at this myself. I've never imaged Uranus. But I may as well while I wait for my new LRGB filter set to arrive.

[matt]

Nah.

The seeing was already crap when I arrived in late July '07.

You can't pin that one on me, bucko!!!!:lol:

[AlexN]

:p :)

[spearo]

very cool stuff and as Striker said, i too love the presentation
very impressive stuff
frank

[Babalyon 5]

Yeah, way cool! Kudos for a not often imaged planet!:eyepop:

[theodog]

Its been a while since I checked this forum out.
I'm glad I did.
What a cracker of an effort.
Well done Dennis!

[matt]

I'm considering having a go at this tonight, Dennis.

Although it's quite windy today, and the seeing's going to be horrid. It probably doesn't matter too much about the seeing, since I'm not trying to capture very fine planetary surface detail as is the case with Jupiter.

I wonder what length exposure I'd need to set using the C9.25, DMK 21AF04 and 3x barlow??? Would it be wise to use some kind of filter (IR)?? Hmmm.

It'll be a night of experimentation.:D

[Dennis]

Hi Matt

Great stuff – if this horrendous wind eases I might just get out there myself as well.

Here is a link to a CN Post (http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/2617862/page/0/view/collapsed/sb/5/o/all/fpart/1)where a guy has used his 8” Newt at F19.6 with a DMK21AF04.AS - you should find his settings in there; I think he was exposing for 2.8 secs at a Gain of 950.

If you want an easy start, I’d go for Neptune at the prime focus of your C9.25; you should be able to pick up his moon Triton quite easily. I usually leave the IR block filter on the DMK camera just to protect the chip from dust bunnies.

Cheers

Dennis

[Deeno]

Very Cool....

[Dennis]

Here are a couple of screen prints from SkyTools:

Neptune – Triton separation 73 arcsec for around 11:00pm.
Uranus – Umbriel separation 17 arcsec at around 9:30pm.

I was using the cooled and more sensitive ST7 at F48 with 15 sec exposures just to get some image scale. Not too sure how tonight’s conditions will hold up for such long exposures!

The Uranian (?) moon positions are not as favourable compared to the time I grabbed them.

Cheers

Dennis

[matt]

As always...most helpful:)

Many thanks, Dennis.

I'll be keeping an eye on the wind conditions. I checked the BOM website and the forecast is for the winds to die down. Fingers crossed.

[Matty P]

Good luck Dennis and Matt. Let's hope the conditions improve and you have a great night. I'll be looking forward to the results if you do.

I'm all clouded out down here at the moment. :(

:thumbsup:

[matt]

Hopefully conditions will improve for you, Matty:thumbsup:

The jetstream's looking 'Super Dodge' for SE Queensland (as per the attached image).

So what's new?!?!?!:lol:

[AlexN]

Nasty looking map Matt... There will be no scope action for me tonight... Maybe lunar photo or two.. but nothing more serious than that...

Or maybe just test the C11 for visual use...

[matt]

Hi Alex.

Yeah...moonage could definitely be an option.

When did the C11 arrive? How exciting.

[Dennis]

We’re still being pounded by the wind here, so maybe just a bit of visual observing will have to suffice for tonight? Must find my set of eyepieces and figure out how to use them! :lol:

Cheers

Dennis

PS – Matt, I read somewhere that the C11’s just don’t cut it, and that the C9.25 is the preferred ‘scope for serious planetary imagers! :whistle::whistle::P:evil:

[AlexN]

it arrived yesterday. unfortunately for me it balances ok without anything on it, it will not balance however with camera/dew shield/heater band etc etc.. I need another counterweight...

I think I'll just use the old 8" tonight.. I'll go somewhere monday and get another counterweight.

[matt]

In which comic book did you read this???:lol:

[Dennis]

I picked up a 5kg cw from Ron (Sirius Optics at Underwood) at the Qld Astrofest as it happened to fit my EM200 mount, although I think it was an EQ6 cw. They may have stock so it might be worth giving the shop a call.

Cheers

Dennis

[AlexN]

Yeah, I'll give them and York Optical a go... Should be around the $55 - $60 mark yeah?

[Dennis]

That sounds about right and yes, York may have stock too so you should be able to pick one up, which is good news.

How much weight do you think you need to balance the C11 when it is fully accessorised and loaded with finder scope, focuser, camera, side-by-side plate, rings, guide scope, etc?

For the C9.25, I need 20kgs (4 x 5kgs).

Cheers

Dennis

[AlexN]

I don't know with the whole setup.. I would imagine 4 counterweights should do it... my guide scope + guide cam + QHY8 + C11 weighs just on 14kgs... The side by side bar and guide ring setup wouldnt weigh 1kg i dont think.... Should be right... we'll have to wait and see i guess

[Dennis]

Hey Matt

I’ve just come inside after looking at both Uranus and Neptune at the F12 prime focus of the Mewlon 180 with the DMK31AF04.AS. I was having to shoot between 5 and 10 second exposures, Gain around 850 and Gamma at 12 just to (barely) record any of the moons. I couldn’t even contemplate putting a PowerMate or Barlow in the optical train to increase the magnification! Neptune's Triton was the easiest of the moons.

It seems that with the 7” aperture of the Mewlon, it’s either the ST7E CCD or no moons! How did you get on with the increased aperture of the C9.25?

Cheers

Dennis

[matt]

Hi Dennis.

I decided to give last night a miss. It was still very windy here at 8.30pm, so there seemed little point in setting up.

A challenge for another night, for me:thumbsup:

[Dennis]

Hi Matt

Yes, it was a bit of a shocker wasn’t it, with the very gusty conditions all day long. The more violent gusts seemed to have abated by around 10:00pm, so I went outside and just had a bit of a play around with a new focusing mask that I had built, so no serious imaging done here.

Cheers

Dennis