Black and White printable map for locating Vesta at s asimilar scale to the images. Elnath and zeta Tau (Tianguan) are fairly obvious and Vesta is near 121 Tau. Click to embiggen | Photorealistic map for locating Vesta (and in conjunction with the printable map). Elnath and zeta Tau (Tianguan) are fairly obvious and Vesta is near 121 Tau. Click to embiggen. |
Stack of 30x 1 second exposures at ISO 3200 with my canon IXUS "point and shoot" on 8 March. Click to embiggen. | Labelled Stack of 30x 1 second exposures at ISO 3200 with my canon IXUS "point and shoot" on 8 March. Click to embiggen. |
Stack of 10x 4 second exposures at ISO 3200 with my Samsung S24 on 8 March. Click to embiggen. | Labelled stack of 10x 4 second expsures at ISO 3200 with my Samsung S24 on 8 March. Click to embiggen. |
So how did my asteroid 4 Vesta imaging challenge go? Remember my original attempt didn't go too well, despite my confidence.
I had a second opportunity on the 8th. The sky clarity was better, I could actually see Tianguan (zeta tau) and Elnath on the back of the camera/phone screen in test shots (there was a lot of groobling around on the ground setting up the shots and several test exposures to get the right patch zoomed in. My Knees do not like me as I did this on the gravel bike path near the beach.
But eventually I got Tianguan (zeta tau) and Elnath framed at a good zoom level (don't ask me what the Zoom is, the Canon IXUS just gives a zoom bar and the Samsung S24 give a zoom level but I forgot to record it. Both the IXUS and Samsung were on a tripod (I have a special adapter to pones for my tripod).
For the point and shoot IXUS I took 30 x 1 second frames at ISO 3200 (f/5.6), as the IXUS doesn't take exposures longer than 1 second (well it does, but defaults to ISO 50!). I traded noise for sensitivity. I also took a dark frame (exposure exactly the same as the main images but with the lens blocked to account for noise. The frames were then stacked in Deep Sky Stacker, the stacked output saved (a TIFF file), then exposure adjusted in The GIMP and the TIFF converted to JPG.
Unlike last time 4 Vesta was clearly (if faintly visible). You should embiggen the images above to see Vesta clearly.
For the Samsung S24 I took 10 x 4 second frames at ISO 3200, f/3.4no dark frame though. The frames were then processed as for the IXUS (stacked in Deepsky Stacker, the stacked output saved (a TIFF file), then exposure adjusted in The GIMP and the TIFF converted to JPG). The result is much better than the single 10 second exposure.
The Samsung S24 is cheating though, few cameras/phones have a 200 megapixel camera. They will be closer to the 20 megapixel IXUS. But the point is that even with an ordinary camera phone and stacking you can take effective astrophotos down to at least magnitude 8. This opens up a world of sky imaging you didn't think you could access with simple equipment.
How did others go, Well Brendan got Vesta on the 9th,
Brenden stacked a sequence in Photoshop. 20 x 5 sec ISO 1600 f/5 42mm on Canon 1000D DSLR on tripod.Vesta is seen faintly above121 tau and has clearly moved since my images on the 8th.
If anyone else has images and wants to submit them, let me know.
Single 10 second second exposure at ISO 3200 with my Samsung S24 on 3 March, Vesta is just visible. | Labelled stack of 10x 4 second expsures at ISO 3200 with my Samsung S24 on 8 March. Click to embiggen. |
In these images from 3 and 8 mrach you can clearly see the movement of Vesta.
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