ISS over Melbourne, 13/2/21

[Tulloch]

The ISS crossed over Melbourne again, nice and high and very bright (-2.6 mag according to SkySafari). I was lucky to get a break in the clouds for the transit, unlucky because I stupidly predicted the wrong path it would take (north of the zenith, not south :doh:), and set up the laptop table in the wrong position and missed half the transit.

In previous attempts I have both overexposed the satellite (gain 335 and 1 ms shutter speed), underexposed it (gain 200, 1.5 ms shutter), so this time I chose somewhere in the middle, 250 gain and 1.0 ms shutter. Like last time, I manhandled my C9.25" on the Evo mount and tried to get the bright white spot in the crosshairs of my 8x50 RACI finder scope with the hope that some frames of the ISS might make it onto the sensor.

These settings are also too high and I ended up overexposing the ISS again, but I managed to get a few frames where it was OK and I was able to see some detail, the best of which is shown below at captured size.

Capture details: Celestron Evolution C9.25" SCT @ f/10, ASI224MC, gain 250, shutter speed 1.0ms.

[JA]

Great detail & final result :thumbsup:

Best
JA

[xa-coupe]

One of the better ISS shots I've seen.

[multiweb]

Terrific catch Andrew. I'd be stoked with that. :thumbsup::thumbsup::thumbsup:

[AdamJL]

that is so cool :)

Imagine being able to see the reflection of an Astronaut doing an EVA

[Tulloch]

Thanks all, I think a single astronaut would be too small to pick up, but I'll keep trying :)

[FlashDrive]

That's quite decent in my books ...plenty of detail can be seen.:)

[MortonH]

Very cool.

[John W]

Well captured Andrew. Regards, JW.

[astronobob]

Thats Awesome Andrew- very well done, sharp, excellent exposure :thumbsup:
Nailed the focus, how did you manage that ?
I tried years ago with a 12" SCT but never nailed the focus, tho maybe using a Dslr & exposure of 1/4000 was not quick enough - that would be 4ms I believe, & could be the issue ?

Yeah, definately a top rate catch there - wicked !

[Tulloch]

Thanks Bob, it is my best one to date. To get this one image, I captured a 26GB movie with over 22000 frames at 100fps over 4 minutes, then used PIPP to filter the frames that showed something bright in those frames and then sort them into "quality" order. Of the 900 or so frames that PIPP ended up with, I then went through them manually in AS!3, only selecting those that were not overexposed, blurry or otherwise unsuitable. This left 37 frames, the best of which is shown here :).

Your DSLR should be able to image the ISS, especially at 1/4000 sec (which is 0.25 ms shutter speed btw), but you really need to get lucky, or plan really well. Because my camera could record full frame at 100 fps I just tried to track the ISS as it moved across the sky with the camera on record. I don't know the frame rate of the DSLR but it's probably not 100 fps. I think the best way of doing it is to point the scope ahead of where the ISS is moving to and let it move across the sensor, that way I reduce any blur from my moving the scope. You might be able to do the same thing, and hope that you can get a few frames on target - the DSLR's large sensor would certainly help here.

Focus was pretty easy, I just focused on a bright star (Sirius) and then left it alone.

Here's an animated gif of some of the "other" frames that weren't quite as good as the first one.

Andrew

[Sunfish]

Remarkable image. Such detail.

[rustigsmed]

excellent capture Andrew!!
I'd be stoked too - i went out for peak but was clouded out.
the gif is great too!

[astronobob]

Yeah, Congratts in order for sure as I definately know what it takes to capture Beauties like this :thumbsup:

I don't have any scopes these days, giving it all a rest for while, well after doing it for 20-25yrs.
I may even restart down the track :whistle: :astron:

These couple of my best from back in 2013 might interest you - check em-out :hi:

http://www.iceinspace.com.au/forum/showthread.php?t=109560

http://www.iceinspace.com.au/forum/showthread.php?t=111774

[Tulloch]

Excellent work Bob, looks to me like you nailed the focus on those images. I assume you just kept the camera continuously taking images while you stayed on target?

Was it 1/400 or 1/4000 sec shutter speed?

Thanks for sharing, they are certainly worth showing again :)

[astronobob]

Cheers Andrew. & yeah, Shooting continious with the cable-release whilst man-handling the scope/s on the EQ6 Mount with a little tension on the clutches, & eye on the finder cross hairs.

1/400th with the ED 100 & 1/1,000th with the 10" Newt.

Was using 1/4000 with the 12" Meade SCT but yeah, never caught a clean shot with the 12" @ 3 meter F/L.

All the best with any future attempts you tackle, I'll look on with interest :thumbsup:

[Hemi]

Great images, best Ive seen, and using my beloved c925 Evo Andrew.

H

[cometcatcher]

Great shots of the ISS!

[peter_4059]

Amazing. Great detail. Well done.

[alpal]

Top set of images Andrew.