Neptune and moon, Triton

[Dennis]

Now folks, you’re just going to have to trust me on this one – it’s not a fake, Photoshop, creative blob! Whilst waiting for Near Earth Asteroid 2008 BT18 to clear some trees, I captured an image of Neptune and his moon, Triton.

Screen copy from SkyTools at http://www.skyhound.com/cs.html

Neptune mag 7.8
Triton mag 13.5
Separation approx 16 arc secs

Brisbane, QLD, Australia
19th July, 2008 at 10:40pm AEST (GMT+10).

Takahashi Mewlon 180 F12 with WO x2.5 Barlow (5400mm at F30).
SBIG ST7E CCD camera, 20 sub frames of 10 secs each.

Cheers

Dennis

[Lester]

Well done Dennis, its good to some different planetary imaging.

[Matty P (Matt)]

Nice one Dennis, you don't see images of Neptune too often.

Very well done.

[ving (David)]

more outter planet work! thats what we want

[Dennis]

Thank you Lester, Matt and Dave, it was a busy session chasing the various targets I had listed for the evening/morning. Sometimes I wish the Earth would slow down a tad, just to let me, and the mount, catch up!

Cheers

Dennis

[Ric]

Well done Dennis, a fine capture.

Cheers

[alphajuno (Dave)]

That's awesome. I liked you Uranus shots too!

[Dennis]

Thanks Ric and Dave.

I would encourage anyone with a ‘scope and ccd camera or webcam to have a go at the moon(s) of Uranus and Neptune. It’s a fun project and you don’t need expensive or sophisticated equipment.

Neptune and Triton are the easiest due to the large separation between the pair and the relatively bright Triton at mag 13.5.

Cheers

Dennis

[iceman (Mike)]

Wow, a 10-second exposure to bring it up.. that sure is faint. Nice work Dennis.

Is your tracking that good or do you autoguide when doing this type of work?

I've been meaning to capture Uranus and Neptune around this time of year while they're well placed - but never found the time. Your images have inspired me again.

Cheers

[Dennis]

Originally Posted by iceman

Wow, a 10-second exposure to bring it up.. that sure is faint. Nice work Dennis.

Is your tracking that good or do you autoguide when doing this type of work?

I've been meaning to capture Uranus and Neptune around this time of year while they're well placed - but never found the time. Your images have inspired me again.

Cheers

Hi Mike

With the WO x2.5 Barlow, I was working at 5400mm F30 so I didn’t even take a look at the ST7’s on board TC211 guiding chip!

I was just tracking, but I did notice that Neptune and Triton were being quite cooperative so I just kept on increasing the test exposures and 10 secs seemed the optimum. I have tried this before and didn’t succeed, so I got lucky this time.

The data was a bit smeared at this fl and exposure so I have done quite a bit of cleaning up in PS CS3.

Here is a single, raw frame for comparison.

Cheers

Dennis

[iceman (Mike)]

Nice one D.

I remember when trying Neptune last year it was barely visible with the 5x powermate, only a couple of points above the noise. I had to drop back to a 3x to get enough light in.

[Dennis]

Originally Posted by iceman

Nice one D.

I remember when trying Neptune last year it was barely visible with the 5x powermate, only a couple of points above the noise. I had to drop back to a 3x to get enough light in.

Hi Mike

I just used the tools in Maxim to measure a single raw image with the following results:

Photons:

• Neptune: 2651
• Triton: 165
• Background average: 118

Here is a composite screen capture from using the Line Profile tool (at 200%). I suspect my DMK data would be swamped by the background noise if I used the webcam!

Cheers

Dennis