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Uranium235

Dusty M45 - LRGB

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Yay! I've finally been able to finish off this one, thanks to a Gerd Neumann flatfield panel that I got a couple of days ago.

It took a while to figure out what would be the right exposure length - though it seemed to be different across all four filters, with L being the shortest (0.15s) and G being the longest (0.6). Im still not sure if im doing it right becuase any more than 16 flats made the calibrated subframe worse than its original. What level of exposure should I be aiming for? 20,000 maximum? (max level of camera is 65,000)

Anyway, it did exactly what it said on the tin and sorted out my gradients very nicely ;) still need a bit more practice though. I had to use a folded A4 sheet to reduce the brightness becuase the sockets on the back of my new 30A bench supply only run @ 13.8v. I could reduce the voltage if it were plugged into the front panel, but its not worth messing up the cables that id spent time on tidying up.

Anyways, here it is:

M45

L(25x360), R,G,B(10x300)

ED80 (0.85x), Atik 314L+, CG5-GT

Calibration: Darks, Flats

Setpoint: -10

Guiding: Some flex issues

Thanks for looking ;)

Rob

attachment.php?attachmentid=74415&stc=1&d=1322675063

post-18171-133877700314_thumb.jpg

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Thats awesome Rob, loads of dust showing, i thought it would be a wider FOV with the ED80, have you cropped it much?

Jamie

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Thanks Jamie ;)

Yes, its cropped a little bit - but only by about 5% because the channels stacked up with a little bit of rotation. M45 is pretty big, but the chip on my camera isnt, so I just aim for the best parts of whatever im shooting. I could do a mosaic, but Id prefer to use a shorter FL and faster FR instead.

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Nicely processed Rob, you've managed to maintain some of the star colours (other than blue/white) which often get lost.

Steve

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Very nice Rob!

Edited by AndyUK

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Thanks guys, I think I could have maintained a bit more star colour, especially that nice red one in the centre. I'll see if I can process it again so I can preserve more colour.

However, later that same evening I slewed up a little from M45 and found this lurking in the darkness NGC1333:

attachment.php?attachmentid=74433&stc=1&d=1322694440

There seems to be a lot of dark stuff there, and clearly its going to take some serious exposure to bring it out. Id probably start from scratch on this one as ideally I'd like it rotated by 90deg.

post-18171-133877700428_thumb.jpg

Edited by Uranium235

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Thanks Rob i get you, i vaguely remember when i first got the ED80 and took a picture with my 1000D that it was a wider FOV so wondered why you would have cropped so much. I googled NGC1333 and i think its definitely worth a go!

Jamie

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That's REALLY awesome... loving the dusty background coming out.

NGC1333 is on my list once I get something long enough focal length yet fast enough to capture it....

Frankly one of the coolest things up there... this is what it looks like if you can get the exposures on it:

http://cs.astronomy.com/asycs/cfs-filesystemfile.ashx/__key/CommunityServer.Components.PostAttachments/00.00.47.62.30/NGC1333_5F00_LRGB_5F00_b.jpg

I just love all the different coloured light coming out from the dark dust from the embedded stars... looks like something right out of a sci-fi film :-)

Ben

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Rob - I'd second (or third) Ben and Jamie... I'd never seen NGC1333 before you mentioned it - What exposure details / filter did you use for the one you took? As you noted, it looks as though it will need quite a few subs to pull out the darkness smoothly, but it sure looks a stunning object - I wish you good luck with it (and some clear skies!)

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Andy, I found NGC1333 by way of it being right next to vdB 17 (which is what I was originally looking for). Having read up a bit more on it, its part of the perseus molecular cloud and also contains LDN1448.

The exposure details on this one is 8x600 so far. I reckon it will need at least 30 to get something nice. Trouble is, the moon is back so that puts the brakes on any LRGB ;) so it might have to wait a couple of weeks.

Ben, you wont need a long FL to get this one with a CCD (if you have one). I did that at 510mm, but 400mm would be good enough (and for quite a few other things too!). I think speed would be very useful on NGC1333, anyone with an AG12 or powernewt could absolutely batter it.

I want to go fast, but I dont want to move away from refractors. About the best option I can see at the moment is to reduce a 90mm f5.5 APO (500mmm) to f4.4 (400mm). That would almost put me on par with a quattro in terms of speed, but it would cost almost 900 quid for the bits ;) ...ouch.

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Cheers Rob - I still feel a bit guilty not being able to help you out on M16 earlier this year, but this one I could definitely get to. If you can get me a Artemis screenshot with a reticle, and let me know which filter you'd like me to have a crack at, I'll very happily have a go with my Equinox 80(?)

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Ben, you wont need a long FL to get this one with a CCD (if you have one). I did that at 510mm, but 400mm would be good enough (and for quite a few other things too!). I think speed would be very useful on NGC1333, anyone with an AG12 or powernewt could absolutely batter it.

I want to go fast, but I dont want to move away from refractors. About the best option I can see at the moment is to reduce a 90mm f5.5 APO (500mmm) to f4.4 (400mm). That would almost put me on par with a quattro in terms of speed, but it would cost almost 900 quid for the bits ;) ...ouch.

Unfortunately, with a DSLR, I do need the extra focal length ;-)

I'd probably be mad to even try and get anything from this target with my current set-up.

Unfortunately I have two options of focal length/ratio.... I have the Meg72 with reducer at 345mm/f4.8 or my new Orion Optics Newt at 1.2m / f6.... and nothing in between :-)

I've managed 10 min exposures guided with a 1.3m fl scope on my mount with the DSLR.... but only a couple... i fear I'd need something like 5hrs of 10 min exposures at ISO1600 on this to get anything at all... probably not worth it, should wait intil 2013 or so when I have a CCD and a faster, more suitable fl scope :-)

Then again, with the 500D and it's TEEEEENY pixel size, I could shoot this with the Meg and just crop it like anything?

There's actually an image of this target in Harrel's gallery on the PowerNewt website... IIRC less than 2hrs of exposures, and it looks pretty darn good :-)

Sorry U235... your M45 thread seems to have been hijacked totally!

Ben

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Sounds ideal Andy ;) thanks!

Its rather an easy one to centre becuase you just need to switch to 4x4bin, 1 sec exposure - then move the bright fuzzy patch to the centre of the reticle. If your goto is well calibrated its not hard to find, NGC1333 is the fuzzy bit.

Will PM you the other details later today (camera orientation, filters, exposure etc) as we need the dark stuff running from left to right, not top to bottom.

All being well, we could do this in one night. Still one problem though.... the moon. Willl check stellarium to see if its possible to start it on saturday.

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... I just checked my next forecast clear night - It looks like Monday (although Saturday might give an opportunity if the rain stops before 10pm). As you noted though, the moon's not great, but if it's clear then it has to be done... (I wonder if it might be worth trying to add some Ha to the mix...?)

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Just to say... good luck guys, look forward to seeing the results if you get a joint project going on this one! :-)

All the best

Ben

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Nice work Rob.

Different exposure times for flats with different filters is normal, and yes, 20,000 ADU with a 285 chipped camera is about right.

Cheers

Rob

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Nice work Rob.

Different exposure times for flats with different filters is normal, and yes, 20,000 ADU with a 285 chipped camera is about right.

Cheers

Rob

Thanks Rob, thats exactly the info I was looking for. Mine worked out at about 30,000, but now Ive installed the appropriate software on the netbook I can measure the ADU as im capturing them. It'l be fun trying to do the NB filters ;)

Ben, I think you may be right in that this is just beyond your current camera. If youve ever tried to do the Iris nebula you will know how hard it is (even with a ccd), I think NGC 1333 will be in the same ball park, probably tougher.

Andy, with a bit of luck we can get out on Saturday. Otherwise it will have to wait a little bit, Ive just looked at stellarium and the moon is bang next to it on monday ;) Also there wont be any Ha in this as is mostly a reflection/dark nebula - though there is a hint of red stuff amongst the dust. You might have to take flats as well, that should fix any gradient caused by the moon. Fingers crossed!

Rob

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Cheers Rob - Fingers crossed for Saturday then... Just FYI, I did some tests a while back for getting 285 flats with the MN190 and an EL panel and noted the exposure values to get 22-23k ADU - As a guide, the LRGB were .03, .16, .09 and 0.055 respectively, with the Ha being a wapping 3.5s!

Obviously they'll be different with the Equinox 80 (I imagine slightly more but at least I know the rough area to start ;))... and by the sounds of it, I need to work out what they'll be before tomorrow night ;)

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Hmmm.... ive just seen tomorrows forecast.... not a happy bunny (ok.. whos been buying telescopes?!). Lets just hope theyre wrong!

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