Saturn, Titan, Tethys & Dione (16th Jan 01:53am AEST)

Dennis · #1 16-01-2009, 06:35 PM

Hello,

Last night I set out to split Sirius A & B with my Mewlon 180 F12, which I did!

Then, I saw Steve’s (Kinetic) post about the Titan event for Saturn so I fitted the DBK21AF04 (colour) and DMK21AF04 (B&W) cameras and grabbed a colour and B&W avi around 1:50am before retiring.

I processed them and merged the output together to show the moons Titan, Tethys and Dione. This took some extensive manipulation of the moons’ brightness so their relative intensity in this composite image is false, although their positions relative to Saturn and each other is correct.

The seeing was very good earlier, but then gradually deteriorated so I pulled the plug around 2:30am as I ran out of gas for the Titan eclipse.

Cheers

Dennis

Kevnool (Kev) · #2 16-01-2009, 08:48 PM

Well done Dennis ,great work.......Cheers Kev.

iceman (Mike) · #3 16-01-2009, 08:52 PM

Excellent work, Dennis! It feels like ages since I've seen some planetary work from you.

Well done on the composite, it looks great. I tried to capture some moons the other day but damn they're faint!

Dennis · #4 16-01-2009, 10:05 PM

Thanks Kev and Mike – this was a real bonus as I didn’t expect the moons to come out.

Mike, I only had the x2.5 Powermate fitted, and although the moons were well below the threshold of the (colour) DBK, the (mono) DMK “easily” picked them up, albeit with 1 second exposures! I would have liked to go longer than 1 second but then Saturn’s brightness would have swamped Titan and Tethys.

It was very interesting seeing the huge amount of colour noise with the DBK at 1/5 second exposure, whereas the DMK image, at 1/15 second was so much smoother.

Interestingly enough, the visual sight through the eyepiece looked very pleasing, although only Titan could be seen.

Cheers

Dennis

Lester · #5 17-01-2009, 08:07 AM

Good to see some more images from you Dennis, very nice.

Dennis · #6 17-01-2009, 11:24 AM

Thanks Lester – I was astonished at how dim Saturn appeared with the ring system edge on!

Cheers

Dennis

AlexN · #7 17-01-2009, 02:49 PM

Dennis.. I think due to the edge on rings this time around capturing a great image of saturn is going to be difficult.. I find with my DBK frame rates and exposure times need to be fairly long in order to properly expose the histogram making it difficult in all but the very best seeing to capture a great image.. None the less you've done very well indeed...

Very clever of you to blend colour and mono data to reveal things that the colour camera couldn't reveal on its own..

Nice image of Saturn Dennis.. Hopefully a sign of things to come this apparition....

Cheers.
Alex.

Dennis · #8 17-01-2009, 03:31 PM

Thanks Alex – yeah, you’re dead right, its going to be one tough apparition so I’ll leave it to you guys in the +11” league; Bird, Mike and you!

IIRC, the DBK21AF04 had gain up around 950 or 1000 and I only managed to ½ fill the histogram using 1/5 second exposures. The live image on screen looked very, very noisy indeed, like a 1600ASA colour film of years gone by.

It’s a pity that I can’t auto record the Gain, Exposure and Gamma settings as part of the AVI file, as I always omit to scribble down the values.

Cheers

Dennis

AlexN · #9 17-01-2009, 03:52 PM

I too always forget to take note of settings used during imaging settings... I know with my DBK when I was imaging saturn a few weeks back the image on screen was very very noisy also.. I was doing 1/10th exposures with gain around the 900 mark.. With any luck it brightens up a bit during opposition and some good images result!