Had a go at doing another mosaic last night, on dark i checked the moon and you wouldnt even shoot it through the ed 80 and webcam ,jumping all over the place, moonset at about 1ish saw the wind drop and skies were clear, so what the hey who needs to sleep, took a bunch of 10x 3 min exposures to merge with a corker that i have of the centre region. when i processed you suddenly realize the difference good seeing makes, i found the focus from one image to the next changing in and out, it wasnt so obvious til i merged the images onto the good one i have...... yep i think we will try again another day..... still i enjoyed having a go and experience is a great teacher.
hello to all that replied, the shot in the middle with the keyhole (the good one) done a week or two ago, the other 3 were done last night and as gary says good practice for later, ive had the middle shot printed as a 14x11 print and it is really sharp....... cant say the same for the rest, never mind ive done worse things...... when i took the good one i originally had 20 exposures to work with but the step ladder i was using touched one of the legs of the tripod so i lost 10 images due to movement when i climbed up to complete the exposure. this is anotrher project to finish but still plenty of time to do it.
Starting to take a pleasing form Alchemy. Well done. I don't think the other frames are too bad. A little deconvolution or minimum filter will shape the stars in subsequent frames and once you raise the black point I think you'll find it difficult to tell the differences between them. Hope you get to finish this piece of work.
eric.. once its complete i will print it out, im trying to get a few to hang on the wall, so far ive got pics of tarantula, m16, a moon mosaic, flame neb, centre of eta, and ngc1365. still plenty of wall space, and with a mosaic you just get so much more definition.
RB thanks for looking.
Jase...... i tried deconvolution on sections of some of the new bits it tightened the stars a little bit (van chittert, somewher between 2.5 and 3.3 cant remember at the moment, 16 levels) also tried lucy/richardson but this doesnt seem to do much, not too sure what a minimum filter is ...
the stars on the new sections are double the size of the old section and at full resolution really noticable,if one pic wasnt so good id probably not complain but... the night was not good for seeing , i checked earlier in the night but got a bit keen when i went out later, i checked the obs report section the following morning and SAB confirmed the poor seeing so at least it wasnt the focus, at only 1/2 hr per frame it can easily be redone it will just sit waiting for a little while til the moons gone ..... sometime after the first of jan.
i bought a red filter today so want to have a quick peek at mars while its at max, and i wouldnt mind having a crack at the homonculus with the dmk in the next week just B/W not colour, i can extend the FL to 15000mm so it might be worth a go.
Jase...... i tried deconvolution on sections of some of the new bits it tightened the stars a little bit (van chittert, somewher between 2.5 and 3.3 cant remember at the moment, 16 levels) also tried lucy/richardson but this doesnt seem to do much, not too sure what a minimum filter is ...
The downside of deconvolution is the effect on nebulosity. Depending on the quantity of iterations, you'll find it will sharpen the highlights, but clip the fainter wisps. I like to blink the pre and post deconvoluted images to see what has happened. If maximising nebulosity is your goal, then be careful.
I posted this on another thread. It should get you going with regards to the minimum filter...
"In relation to the minimum filter, I'm assuming you're familiar with the colour range tool as you'll need to use this for star selection. There are other advanced methods for star selection, but the colour range tool does a fair job.
Once you've got only the stars selected and have feathered the selection (say by 2 pixels), apply the minimum filter - Filter | Other | Minimum. Typically 1 pixel is sufficient. This will also bring back the star colours and reduce bloating. Make sure you feather! Feathering applies to just about all PS selection functions in astro image processing. Failing to feather results in abrupt/harsh results."
Thanks for the advice jase, as always youre willing to pass on your knowledge in the processing dept.
i will have a go with this method and see what sort of results i can achieve.
this is anotrher project to finish but still plenty of time to do it.
