Jupiter, 8th April 2007

[bird]

Made a late decision yesterday evening to head out and try my luck with Jupiter, mostly a waste of time as it turned out as the easterly breeze always brings poor seeing and cloud, but there was one run which came out ok, before the clouds rolled in and ended the party... so here it is.

Capture details: 50 seconds each channel @ 40fps, f/40
Scope: http://www.acquerra.com.au/astro/lexx.html

regards, Bird

[matt]

Nice work, Anthony.

So these were captured shortly after 2am, our time?

I was already clouded in by then:sadeyes: Should've already been capturing AVIs but I was waiting for later GRS transit.

Silly me.

[iceman]

Definitely worth it, Anthony.. A very interesting blueish barge feature in the NTZ.. what is it?

[bird]

I think 1700 == 3am. The poor seeing was already coming by then, but the clouds didn't arrive until about 4.30am. I could see Oval BA later on but didn't capture anything worthwhile.

cheers, Bird

[davidpretorius]

still lotsa detail.............are you out tomorrow morning????

[matt]

Aren't we now only +9 hours ahead of UT???

That would make it 2am.

Anyhoo... nice capture:)

[iceman]

We're GMT+10, Matt.

[bird]

We were GMT+11 during daylight saving, now we're back to normal GMT+10.

Here's one more image from the end of the session, just before I started to pack up.

regards, Bird

[matt]

Ah yes.

Was getting confused with the fact we're currently only 9 hours ahead of London.

The "Your Zones" panel shows it. London:11.13am, Canberra 8.13pm

Have been phoning the UK this weekend and having to try and make the time adjustment.:)

[bird]

I also had a first go at comparing my DX to a Dragonfly2 (on loan for a couple of weeks) and a DMK21AF04. Lessons learned:

- Clean the ccds of any new camera before you go out - the DMK was covered in black spots :-(

- My capture software needed extra tweaking so that it records the name of each camera, otherwise it gets confusing later on telling some of them apart, especially since I tried setting the DX and DR2 to the same settings for comparison.

- I need my 4x powermate instead of the 5x for the DMK, Jupiter is too big otherwise :-)

Next clear night (maybe tomorrow night) should be good for doing some real comparisons.

regards, Bird

[matt]

Yep. I had that messy CCD in my DKM, too

[iceman]

Interesting, Anthony.. Can't wait to see the results.

[John K]

Great images there Anthony as always. The smoothness of the images generated by the camera is great and sure beats a webcam. Thinking that I will have the patience to survive with my SPC900 for only another 6-12 months!

[davidpretorius]

hmmmmmmmmm, so the dragonfly 2 has smaller pixels????

should that be a bad thing or a good thing?

[iceman]

The DMK has smaller pixels, DP. I assumed the DX and DX2 are the same?

[bird]

Size-wise the DX and DR2 both have 7.4u pixels, although they use different ccds. The DMK has 5.6u pixels.

DX = Kodak KAI-0340DM
DR2 = Sony ICX424AL
DMK = Sony ICX098BL

Comparing sensitivities is tricky, as I don't know how the cameras are calibrated, ie I don't have any real way to measure the 0db gain sensitivity (I'd need a carefully controlled light box with known spectrum).

The DX and DR2 seemed very similar in my initial tests, but it later occurred to me that PGR (the manufacturer of both cameras) could easily have calibrated them at the factory to be like this. It doesn't really say anything about the actual ccd sensitivity.

However the DX has gain up to 30db and the DR2/DMK both stop at 24db. The extra 6db makes a big difference in practice. It's the difference between a dim image and a nice bright image.

The 16bit modes of the PGR cameras is also nice, and it is even more important when you are using a short shutter / high fps, as it allows the camera to more accurately digitise the lower signal level.

Bird

[RB]

Awesome work Anthony, love the image scale.