been a while since any imaging can be done here in Melbourne, this image was taken back on 4th july.
Have had some issues with flexure in the system, my current suspisions are centred on the focuser (gso 10.1) as its not a premium job. have since relocated and tied the cabling so as to not apply and inadvertant pressure as it moves...... if the weather clears i will find out if i was right, perhaps an upgrade to a JMI event horizon focuser may help ????...feel free to make sugestions
Anyway the technical details
Mount Losmandy G11
Scope 12 inch f5 newtonian
Guiding PHD 1 sec updates, .5 sidereal 20% aggression, through ED80
Camera QHY8
Exposures 17 x 6 min
also added m20 shot the same night... only 6 or 7 exposures due to trailing of stars so its a bit gritty.
Beautiful results Clive!
Yes the dust does stand out nicely in the M20 shot!
Have you tried a reinforcing plate/base under the focuser to strengthen the OTA.
I have heard that the focuser causes flexure problems with the tube wall bending under the weight of the focuser/gear attached. I shall be doing this with my OTA. Might be worth checking out as well?
cheers Gary
thanks eric it looks like m20 is the favorite having a squiz at the other replys. you know its about time you got that 10 inch scope out and travelled out from the bright lights for a night and got your hand back in, i miss the way you used to image.
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Both really nice shots Clive but I agree with Eric M20 looks great, with lots of outer nebulosity and some nice greeny brown dust visible.
Mike
thanks mike , i just wished i got more usable shots from the 15 frames i took, if the sky clears i would like to add more to this image.
[QUOTE] MULTIWEB M20's awesome. What gain and offset did you use with the QHY8?
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i used gain of 50 and offset of 117...... i find it interesting that people are shooting with a gain of 1 or 2 yet with DSLR cameras no-one shoots at ISO 100 , given the camera is so noise free why wouldnt you bump it up a bit. (my 2c worth)
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Brown dog Wow - that M20 is a very nice image. It looks great on my monitor.
Nice capture and nice processing.
Thanks browndog , there is so much difference in some monitors its hard to know if you got it just right, i use my laptop mostly so i can be semi sociable while i process the images with my wife, (she doesnt mind because she gets to watch what she wants on the TV then) my worry is the greens which dont show up too well on this screen.
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Have you tried a reinforcing plate/base under the focuser to strengthen the OTA.
I have heard that the focuser causes flexure problems with the tube wall bending under the weight of the focuser/gear attached. I shall be doing this with my OTA. Might be worth checking out as well?
cheers Gary
thats a peice of gold gary, i dont recall anyone here having done it here before, what gauge and type of metal would you consider using and how big.... its quite possible that could be happening as 12 inch is a large tube and its pretty thin too. (Congrats on the image for the Malins it was a beauty )
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HAGAR Very Nice Clive, You seem to have it all working well. Question: How did you get the clouds to part? Help needed.
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I wish i knew doug , we need some help here too, this was shot 2 weeks ago, i can only reprocess it so many times so i need more data to work with now. i think i have accumulated about 10 hours in 3 months
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Pride of the fleet Clive...very very nice indeed!
kind words peeb61 but i think theres quite a few much better than i. still glad you liked it
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Both great shots. The M20 is the standout but then NGC6357 is not a very photogenic target.
Greg.
thanks greg, ive got lots of other things to image .... this weather down here in melbourne has hampered things somewhat, still want to do Ms 16 and 17 sometime this year
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Very nice images, well done Clive.
thanks lester, the big observatory in your Avatar.... that yours??
Nice work Clive. M20 is a cracker image. Nicely processed. NGC6357 looks like it needs more exposure time or some data through a ha filter to bring out the details. Still another fine image under the belt. Well done.
thats a peice of gold gary, i dont recall anyone here having done it here before, what gauge and type of metal would you consider using and how big.... its quite possible that could be happening as 12 inch is a large tube and its pretty thin too. (Congrats on the image for the Malins it was a beauty )
Don`t really know what would work best but with mine I just used a off-cut from my second hand tube as I have a spare 200mm of tube as it was a f/6 tube. Made a plate 150 x 125mm to go under the focuser. Screwed and also epoxied down. Its only thin like 1mm thick but I hope it will make it extra rigid..With your 12" tube I reckon a bit larger and heavier gauge plate would be better. At least it is a cheap mod to try...
cheers Gary
JASE NGC6357 looks like it needs more exposure time
yes no doubt, i watch the better imagers in this forum and they are going 6-7 11 hours for the data, clearly this is the way to go for better images..... just struggling at the moment to get even a clear sky
As always thanks for your constructive input. the m20 was the easiest to process, i guess the brighter objects always will be though.
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ICEMAN I've missed your work, Clive!
me too, the weather has been cloudy for soooo long.
GARY thanks for your ideas i think its worth a try, it would eliminate another possibility for movement.
