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View Full Version here: : ED 127/QHY 8/H alpha -Lagoon


seeker372011
21-09-2008, 11:08 PM
here's my first H alpha image with the ED 127

finally got the EQ6 to autoguide Friday night so naturally cloud intervened before I got very far

the last sub was shot through plenty of cloud

as a result this is only 50 minutes of exposure so its also a bit noisy

600secs x 5
ED127
EQ6
QHY8
Baader 7 nm H alpha Filter
PHD guiding
DSS and Photoshop for stacking and processing
for a larger image:
http://www.flickr.com/photos/91784720@N00/2875480444/sizes/o/

for an even larger close up crop

http://www.flickr.com/photos/91784720@N00/2874654031/sizes/o/in/photostream/

these are not too large (about 500 k each) so do have a look if you can

I had some wierd eggy stars in the left hand side so had to crop those out-not sure why yet, didnt find them in other images with the ED 127-

otherwise think the ED 127 is delivering on its promise

your comments appreciated

Narayan

Gama
22-09-2008, 12:26 AM
Every man and his dog that owns a QHY-8 is doing H.a now.
Geez, people get hooked on narrow band imaging easy. Suppose its light pollution moving them in that direction.

Looks great by the way.

Theo.

iceman
22-09-2008, 04:49 AM
Lovely images, Narayan. Beautiful contrast and detail.

AlexN
22-09-2008, 10:45 AM
Agreed. It looks fantastic. especially for 5x10mins.. Do you plan to add more data to this in the future?

As Theo said, there are a lot of QHY8 users narrowband imaging at the moment.. I've only used mine once and since doing so I've bought a H.a. filter due to the light pollution in my area, and also the added advantage of being able to shoot during the full moon.

RB
22-09-2008, 10:48 AM
Nice and sharp with good detail.
Well done Narayan.

Ric
22-09-2008, 10:50 AM
Lovely image Narayan, the Ha certainly brings out the clarity and detail.

Cheers

Astrod00d
22-09-2008, 11:09 AM
Great result there Narayan, good depth and detail. Looks as if the EQ6 is guiding OK now.
The eggy stars you mentioned at one edge only... The 127mm APO has quite a flat field so optics probably aren't the cause. Check that the QHY8 is correctly seated in the focuser and hasn't tilted sideways. The compression ring in the 127mm APO focuser has a tendency to force things sideways resulting in different focus from edge to edge.

Cheers,

Rob

h0ughy
22-09-2008, 11:27 AM
that is an understatement Rob - I bough t a new moonlite for my focuser.

I am so impressed with this shot Narayan, shows what is possible with the scope:thumbsup:

Hagar
22-09-2008, 11:30 AM
Very nice result Narayan. I don't think it is a noise problem it is more likely to be just the fact that the Ha requires a lot more exposure than does the standard RGB image. I have recently shot a couple of 30 min exposures with the QHY8 and found near enough to no noise even at this exposure.

Looks good , Keep em coming.

multiweb
22-09-2008, 01:42 PM
Very cool. Which channel do you use when you debayer? Do you only keep the red and throw the rest?

Phil
22-09-2008, 05:02 PM
great shot love the HA photos.
Phil

seeker372011
22-09-2008, 06:10 PM
While this was a first H alpha with the ED 127, Theo, I have had the QHY8 for 4 months-and have only taken one RGB image I think from memory with my ED80. The real reason for shooting in H alpha is of course I can image from home despite the light pollution

I will try and add colour-for objects high in the sky I can shoot RGB using real short exposures.

for too many objects-which dont rise high enough in the sky- its not possible from home-rgb images have this awful greenish cast and no amount of gradient exterminator really overcomes this

Rob I think you are right , I will go and check my subs, the wierd eggy stars in one corner may be due to slippage in one or two frames as the night went on

seeker372011
22-09-2008, 06:13 PM
I throw away the green and blue channel-which have only noise pretty much and convert the red to grey scale

DSS has an option to stack H alpha images but I dont like it as it reduces the size of the image by 50% -so I just use standard AHD debayering and then take the stacked image to photoshop

seeker372011
22-09-2008, 06:15 PM
oh there's no noise in the raw frames Doug, its just when I stretched aggressively it added noise. More exposure-say two or three hours more would help, thats for sure


Thanks everyone for the interest. As Houghy says this scope seems to have potential, even if it has a dodgy focuser

Narayan

multiweb
22-09-2008, 09:20 PM
Exactly my problem. I did a bit of RGB from my backyard and it's a real processing challenge to extract anything out of the greenish sky glow. I still can't believe how crisp your pictures of M8 are. I did a RGB 10x10min from really dark skies on the same object and I can't even match 50% of the nebulosity you've captured in a light polluted environment. I'm converted if I can do luminance from home. My baader filter's on order. :)

bluescope
23-09-2008, 12:10 AM
Looks real good Narayan, excelent detail throughout the neb. Where's the best place to buy the Ha filters from ? I think they would be handy whether in light polluted areas or not.

:thumbsup:

winensky
23-09-2008, 02:53 PM
A lovely bit of Ha. Yes it is flavor of the month, (or dare I say that time of the month), :whistle:to get some worthwhile images. The real star is the ED 127. great sharp image.

allan gould
23-09-2008, 03:30 PM
Have the moonlight focuser for the 127mm APO, have just bought a QHY8 and need the H alpha filter. What do you guys recommend as I will be shooting through light pollution of Brisbane.
Tried a semi-apo Baader but it couldnt cut through the light pollution.
Allan

allan gould
23-09-2008, 03:32 PM
Narayan
Have a good look at your focuser. Mine would give a slight tilt to one side as a tensioned up the focuser grip. This can give slight egg shaped stars to one edge of the photo. Thats why I bought the Moonlight focuser.
Allan

seeker372011
23-09-2008, 06:31 PM
Thanks Allan, I will have close look in daylight at the focuser

I can recommend buying a Baader 7nm H Alpha from OPT in the US-it was heaps cheaper than I could buy locally and plus they had it in stock. came quite quickly

and I got made a lifetime member of the OPT club entitling me to a discount on future OPT purchases ;)-guess no one escapes that privilege

Bassnut
23-09-2008, 06:46 PM
That, Narayan, is very impressive, striking, excellent work.

seeker372011
24-09-2008, 09:46 PM
thanks Fred!

Tandum
25-09-2008, 12:49 AM
I agree ... It is a attractive image ... an excellent result.