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[1ponders]
16-01-2005, 04:08 PM
Around the 14th of January both asteroids Flora (8) and Herculina (532) reached opposition. After a bit of trial and error and a lot of juggling of focal lengths and image size adjusted in PS I've manage to put the few images together.

The images don't quite line up correctly if you download them and view them in windows picture and fax viewer as they were taken at two different focal lengths. I've adjusted them as best I can at this time. Both were taken with Canon 300d, one with and EF80-200 mm lense @ 200mm (had trouble with this lense with blooming off one side of the star images), and the other an EF 28-90 mm lense @ 90mm. All were taken at ISO1600, one at 45 sec and the other at 50sec. They were taken piggyback mounted on LX200.

These have then been cropped, rotated and resized in PS with minimal image enhancement apart form resetting black point, despeckling, sharpening and brightness and contrast adjustment.

I've tried this exercise, not to produce a visually pleasing image, but simply to try to track these two asteroids. The bright star is saturn.

A couple of things I've learnt out of this exercise are:
1. :) don't change lense focal length :)
2. take the images at close to the same Sidereal time as possible to stop the need to try to rotate the photo to line up stars. (which is a pain in the butt when you use different focal lenths)
3. In Alt/Az mode use a fairly shot focal length to get as much of the center of the image not rotating. It center can always be cropped, enlarged and enhanced.
4. for brighter asteroids 45 - 50 sec is long enough. (about 8.5 - 9.8 in this case)

Cloud cover at midnight - 2:30 has restricted me to only two imaging sessions. The first was the 12/1/05 and the other 14/1/05 (opposition for flora)

Any suggestion for improving my chances of catching these allusive celestial bodis is appreciated.

This first two images show both Flora (nearer to Saturn) and Herculinia (bottom right hand corner)

[1ponders]
16-01-2005, 04:09 PM
The 14/1/05

[1ponders]
16-01-2005, 04:11 PM
The next two shots are closer views of Flora only. Again 12/1/05 and 14/1/05

[1ponders]
16-01-2005, 04:13 PM
Positional change is fairly obvious

beren
16-01-2005, 04:28 PM
Hey nice work Paul , been meaning to do something similar ,cool.

silvinator
16-01-2005, 04:32 PM
Nice work ponders! I think you did a great job with the first image. The other images are great in showing how fast they move relative to the background stars. Job well done consdering you picked really tough targets.

[1ponders]
16-01-2005, 04:34 PM
Its challenging fun Aragorn. Especially trying to line the images up and use the windows picture and fax viewer as a blink comparitor.

beren
16-01-2005, 05:01 PM
:) i like the idea of tracking objects against the backdrop of the stars using maps but to do it on film instead of sketch would be neat.

[1ponders]
16-01-2005, 05:16 PM
I must admit that I would have found it much more difficult with out using an updated planetarium program (in this case Autosuite). It was an invaluable assistance in detemining angular separations from saturn and Pollux and Flora and Herculinia and consequently suitable lenses focal lengths. As it was I could have imaged through anything up to 500 -600 mm and still been able to get both in the field of view.

Its also convinced me that I need to clear some trees around my place (at least the bloody great leopard tree on my nortern boundary) so I can prime focus through my LX200 in equatorial. I can't see low enough to the east, to drift align and the only place I can use iteration alignment I cant see much of the ecliptic (about 10 degrees thanks to the leopard tree, luckily its a bit of a weed up here and its growing over powerlines.)

Thanks for the comments guys

beren
16-01-2005, 05:31 PM
Paul i have a house blocking my eastern view so i roughly have a 20-25 degree {1 handspan at arms length eyelevel}limit but still i manage to get pretty good drift alignments done , if there isnt any brightish stars around i use one thats visible using the finderscope . You can also use the western horizon but you have to reverse the adjustments.

gbeal
16-01-2005, 05:37 PM
Nice work Paul.
I wonder if they show as a trail or are they too far apart.
Gary

rumples riot
16-01-2005, 05:59 PM
Nice shots Paul, something a little different.

On a friendly note, you might like to check your collimation. I recognise the funny little tail like objects on your stars. My stars use to do the same until I got bobs knobs and fixed my collimation up.

Other than that their great

beren
16-01-2005, 06:08 PM
Think Paul was piggybacking the camera , tricky thing to do because the focusing screen is so dim , well on my FE2 anywhy, even when its set at infinity

[1ponders]
17-01-2005, 10:25 AM
Yes I was piggy backing. And your right Aragorn, not an easy task getting that small dim image focused.

Garry I was hoping to get one photo a night for two weeks and put together a animated gif. Unfortunately I've only had two nights out of 6 up the last date of these images.

I'm looking forward to my next plantetary/asteroid conjunction to try again. I've learnt heaps out of this so hopefully the next one will be better focused and of a higher quality.

Thanks for the feedback

rumples riot
17-01-2005, 11:40 AM
Sorry Paul, my mistake. Feel like a dill.