The Golden Prawn - with AG12

[strongmanmike (Michael)]

This is my first deepish image with teh 12" F3.8 astrograph.

After spending quite a while trying to tweek the colllimation on-camera using trial and error and basically going around in circles ...I got lost so pulled the camera and corrector off and just recollimated with the Catseye tools....it's pretty close

Anyway..corner stars not perfect but everything else went well at least and after the high cloud cleared on Saturday night around midnight, I grabbed this reasonably deep image of the Prawn Nebula with just 60min each of SII, Ha and OIII...The Prawn region is not that bright really and I couldn't have gone this deep this easily with the Starfire

Full frame images 1.8deg X 1.8deg field of view

Large image (use your browser to shrink it if you like)

Small image

Crops

Slight crop for a tighter composition

Just the Prawn

Tested out the dew prevention too as the night was dew laden, the AG12 OTA has a heater molded into the tube just above the primary mirror and a heater pad is mounted behind the secondary so with the three rear mounted fans sucking air down the tube all night no dew formed on the primary, secondary or the corrector, so that was a possitive - see the photos of the scope in the morning here and here

Sadly although I have resisted and hoped it wouldn't be necessary...I need an off axis guider or at least need to try stabilising and shortening my guide scope-camera setup (see above photo), 5min subs is all I can get and even that shows some trailing at times ...lucky she is big and fast! ...all part of the learning curve

Hope you liked the darstedly narrow band colour pallet this time

Mike

[gregbradley]

Wonderful image Mike. Got to be happy with that. I like the tiny stars. I think apart from getting deep fast that will be a very nice aspect of these AG12 images. These fast Newts seem to get smaller stars than APOs. Lots of detail in the faint background nebula. This would be a great scope to pick up integrated flux nebulas.

Offaxis guiding is totally the way to go. You have more prospect of flex with this setup than your AP with its rigid tube and solid focuser. I tried to use a guide scope on the CDK17 and no way Jose. I just did a run of imaging using a MMOAG on the TEC180 and got rid of the guide scope. What a difference. Fabulous. Plus my setup requires one less counterweight. I saved on the weight of the guide scope, rings. Plus a guide scope makes the setup top heavy which affects balance differently at different angles. The scope is now easier to balance. The MMOAG setup I use is about 55mm thick all told with the adapters.

http://www.pbase.com/gregbradley/image/134562827/large

As far as elongated stars in the corners (not noticeable in the image really unless you super look for it) I imagine that is either a spacing issue or the corrector is not correcting all the way to the edges. I have an FS152 4 inch reducer and it starts to affect corner stars even with the ML8300 chip which is smaller than a DSLR. I could be wrong but I don't think collimation causes elongated stars at the corners. What's your experience with this? I have seen incorrect spacing cause this. I have an AP155TCC corrector/reducer for the AP140. I had it slightly off on one setup (its very sensitive to correct spacing +/- 1mm) and it caused elongated corner stars.

Greg.

[SkyViking (Rolf)]

What a great image Mike, the stars look pretty sharp to me and both the target and composition and colours are just wonderful. Definitely a nice achievement for the new scope I reckon.
I wonder what it would look like if you swung it over to Centaurus A and did an Ultra Deep Field... maybe we get to see that in the not too distant future

Although I'm sorry to hear that your guiding setup is not up to handle the new OTA it is somewhat comforting for me to learn that OAG is apparently the way to go, since I'm leaning towards the QSI with inbuilt OAG, as you know. I hope you find a solid OAG soon so you can take those deep fields

Thanks for the view, it looks very promising!

[gbeal]

Nice shot Mike, and good to see a few of the New Lambton Observatory as well, nice looking setup.
While I too am leaning towards an OAG, maybe you could try the finder-guider setup like I have. Converted 50mm finder, with (in my case) a Lodestar or ExView guider fitted, solidly. Mounts close in on the saddle, and is a "fixture" with the saddle and mount, regardless of the imaging scope.
Worth a shot anyway.
Gary

[multiweb (Marc)]

Great prawn mate! Sizzled to perfection. Good on you to brave the dew. It's driving me nuts lately. I'm interested in your primary heating system. Where exactly is it located? Between the fan and the primary or between the primary and the secondary? On the tube or the primary cell itself?

[marc4darkskies (Marcus)]

Yooouuuuu're baaaaaack!

Lovely image Mike! For a NB image that is ... I like the colours you've mapped - very appealing.

Yeah - I reckon you need to ditch the guidescope so you can go for longer subs. You'd make some really deep images from a dark sky!

In spite of Gregs comments I'm not sure your stars are as tight as they could be given the image scale (?) Was the seeing a bit off? Maybe a bit of decon needed? Their shape looks dead on though. If anything only a slight probs at the corners but not worth worrying about IMO.

Cheers, Marcus

[Stevec35 (Steve)]

Lovely image Mike. Tiny stars and nice colours.

Cheers

Steve

[TrevorW]

Fine image that, and I like the colour composition

[jenchris (Jennifer)]

When you post a pic like that, I feel totally demoralised - since not only is the image superlative, the jargon surrounding it isn't recognisable -- integrated flux nebula -- what's that, back to the future??

It is beautiful and I don't even know where it is in the sky or even if my scope can see it, which makes me an ignorant tart I guess.

[Paul Haese]

Great stuff Mike. Colour is lovely, stars on axis are very good and image brightness is superb.

OAG will help you greatly. I will never go back to a guide scope again if I can help it. The benefits out weigh the frustrations by miles.

That is not collimation as a problem in the corners. You have field curvature there. As Greg said spacing needs to be sorted. When you get that right your stars will be pin sharp all the way to the corners.

Excellent start.

[Hagar (Doug)]

Great start Mike. Can't say I like the colours myself but the detail is great. A few small reflections on some of the bright stars but that is one of the bains of using filters. I can't believe the detail you have captured with just 60 minutes of each filter.
I have been playing around with a cheap Orion OAG and think this is the way to go. I now want something a bit bigger but will have to make up some adapters for whatever I buy. No one seems to make an OAG with 54mm adapters built in to fit either Atik or QHY filterwheels or cameras.
They certainly are a bugger to setup but the gains outway the problems of setup. Once you have all the spacing setup it's quite easy then. Just one focuser to worry about.
12 months back I wouldn't have contemplated an OAG and now would struggle to go back to the separate guide scope.

Keep them comming Mate. Great to see you getting some use from this new beast. Looking forward to some great RGB.

[renormalised (Carl)]

Yum.....done in lemon butter!!!. Not bad for a first try of the deep fried prawn That 12" "astrobarbie" is a good one to throw a few prawns on

[Tom Davis (Tom)]

Love it, Mike! This is a great image

Tom

[DavidU (Dave)]

Ooooh, that's a big fat bright image. Lovely.

[richardo (Rich)]

Ah Mike, this is just lovely!!
Great to get the detail and signal in so fast... aint it!!
Love the palette choice.... just what this area needs I reckon.
When I've imaged it, it always look very flat with BB filters, even with Ha thrown in...

I too love the small stars that the NB has brought to the image and I also like the bubble/ halos about the brighter stars.. i think it's a non issue.

For 160' worth of data.... this is very smooth and detailed!.

As for the small issues.... hell, who needs 10' plus subs, fast reflectors will do great with less

All in all, lovely image mate... big congrats with the scope!!
Ps love that focuser.... I've got a new Feather touch coming in a few days... think this will solve my flex issues..(every thing else is rock solid but the ML) but I did price the PDF...then I quickly changed websites to a more affordable focuser
'If I had money, I'll tell ya what I'd do, I go down town and by a...... hell of a lot of very very expensive astro things

All the best for now
Rich

[strongmanmike (Michael)]

Originally Posted by gregbradley

Wonderful image Mike. Got to be happy with that. I like the tiny stars. I think apart from getting deep fast that will be a very nice aspect of these AG12 images. These fast Newts seem to get smaller stars than APOs. Lots of detail in the faint background nebula. This would be a great scope to pick up integrated flux nebulas.

Offaxis guiding is totally the way to go. You have more prospect of flex with this setup than your AP with its rigid tube and solid focuser. I tried to use a guide scope on the CDK17 and no way Jose. I just did a run of imaging using a MMOAG on the TEC180 and got rid of the guide scope. What a difference. Fabulous. Plus my setup requires one less counterweight. I saved on the weight of the guide scope, rings. Plus a guide scope makes the setup top heavy which affects balance differently at different angles. The scope is now easier to balance. The MMOAG setup I use is about 55mm thick all told with the adapters.

http://www.pbase.com/gregbradley/image/134562827/large

As far as elongated stars in the corners (not noticeable in the image really unless you super look for it) I imagine that is either a spacing issue or the corrector is not correcting all the way to the edges. I have an FS152 4 inch reducer and it starts to affect corner stars even with the ML8300 chip which is smaller than a DSLR. I could be wrong but I don't think collimation causes elongated stars at the corners. What's your experience with this? I have seen incorrect spacing cause this. I have an AP155TCC corrector/reducer for the AP140. I had it slightly off on one setup (its very sensitive to correct spacing +/- 1mm) and it caused elongated corner stars.

Greg.

I agree, I am now pretty sure the star issues is a spacing problem, must be very slightly too long or two short, probably only a mmm or two?.. not sure how t happened either as I used all the right measurments and the adpater made by OO measures up to the specs I supplied

Yep looking seriously at the MOAG and the Mitsobusi (sp?) unit from Hutech now...I think I might just cut to the chase rather then stuff around with shortening the guide scope etc..? more money though

Originally Posted by SkyViking

What a great image Mike, the stars look pretty sharp to me and both the target and composition and colours are just wonderful. Definitely a nice achievement for the new scope I reckon.
I wonder what it would look like if you swung it over to Centaurus A and did an Ultra Deep Field... maybe we get to see that in the not too distant future

Although I'm sorry to hear that your guiding setup is not up to handle the new OTA it is somewhat comforting for me to learn that OAG is apparently the way to go, since I'm leaning towards the QSI with inbuilt OAG, as you know. I hope you find a solid OAG soon so you can take those deep fields

Thanks for the view, it looks very promising!

Cheers Rolf, yes preliminary results are very promising, once I have the outer stars perfect and the guiding back to AP like standards this will be a killer scope for sure!! it's already pretty good Off axis huh?...never thought I'd need it oh well at least it all seems to be on track.

Originally Posted by gbeal

Nice shot Mike, and good to see a few of the New Lambton Observatory as well, nice looking setup.
While I too am leaning towards an OAG, maybe you could try the finder-guider setup like I have. Converted 50mm finder, with (in my case) a Lodestar or ExView guider fitted, solidly. Mounts close in on the saddle, and is a "fixture" with the saddle and mount, regardless of the imaging scope.
Worth a shot anyway.
Gary

Cheers Gary

May be..?..I'm just thinking if I bite the bullet and go down the off axis route to start with I may be taking those 20min subs at F3.8 a little sooner

Originally Posted by multiweb

Great prawn mate! Sizzled to perfection. Good on you to brave the dew. It's driving me nuts lately. I'm interested in your primary heating system. Where exactly is it located? Between the fan and the primary or between the primary and the secondary? On the tube or the primary cell itself?

Thnaks Marc

The heater strap is molded into the tube in-line with the primary mirror.
You can see it here at the back of teh tube (mirro removed) http://www.pbase.com/strongmanmike20...98033/original

Originally Posted by marc4darkskies

Yooouuuuu're baaaaaack!

Lovely image Mike! For a NB image that is ... I like the colours you've mapped - very appealing.

Yeah - I reckon you need to ditch the guidescope so you can go for longer subs. You'd make some really deep images from a dark sky!

In spite of Gregs comments I'm not sure your stars are as tight as they could be given the image scale (?) Was the seeing a bit off? Maybe a bit of decon needed? Their shape looks dead on though. If anything only a slight probs at the corners but not worth worrying about IMO.

Cheers, Marcus

Glad you liked it, couldn't let you have ALL the glory with that mediocre TOA shot of Cen A

Agree re the stars but I think they are close: http://www.pbase.com/strongmanmike20...90322/original


But as you say the seeing wasn't perfect either.

Originally Posted by Stevec35

Lovely image Mike. Tiny stars and nice colours.

Cheers

Steve

Thanks Steve so far on track

Originally Posted by TrevorW

Fine image that, and I like the colour composition

Thanks Trevor, colour was thought about very carefully this time after the Eta trials

Originally Posted by jenchris

When you post a pic like that, I feel totally demoralised - since not only is the image superlative, the jargon surrounding it isn't recognisable -- integrated flux nebula -- what's that, back to the future??

It is beautiful and I don't even know where it is in the sky or even if my scope can see it, which makes me an ignorant tart I guess.

Glad you enjoyed the vire Jennifer this nebula is right near the first bend in the Scorpions tail

Originally Posted by Paul Haese

Great stuff Mike. Colour is lovely, stars on axis are very good and image brightness is superb.

OAG will help you greatly. I will never go back to a guide scope again if I can help it. The benefits out weigh the frustrations by miles.

That is not collimation as a problem in the corners. You have field curvature there. As Greg said spacing needs to be sorted. When you get that right your stars will be pin sharp all the way to the corners.

Excellent start.

Cheers Paul, as I have said above, agree re the stars just had to play a process of elimiation and collimation tweeks don''t improve or evn chnage it so it must be the spacing

Originally Posted by Hagar

Great start Mike. Can't say I like the colours myself but the detail is great. A few small reflections on some of the bright stars but that is one of the bains of using filters. I can't believe the detail you have captured with just 60 minutes of each filter.
I have been playing around with a cheap Orion OAG and think this is the way to go. I now want something a bit bigger but will have to make up some adapters for whatever I buy. No one seems to make an OAG with 54mm adapters built in to fit either Atik or QHY filterwheels or cameras.
They certainly are a bugger to setup but the gains outway the problems of setup. Once you have all the spacing setup it's quite easy then. Just one focuser to worry about.
12 months back I wouldn't have contemplated an OAG and now would struggle to go back to the separate guide scope.

Keep them comming Mate. Great to see you getting some use from this new beast. Looking forward to some great RGB.

Thanks Doug, appreciate your considered comments and I think I agree with them

Originally Posted by renormalised

Yum.....done in lemon butter!!!. Not bad for a first try of the deep fried prawn That 12" "astrobarbie" is a good one to throw a few prawns on

Thanks Carl, yeh it looks like buttered prawns huh?

Originally Posted by Tom Davis

Love it, Mike! This is a great image

Tom

Cheers Tom, not quite an AP RH but once tuned I think the AG will be formidable too and a geat dust buster..?

Originally Posted by DavidU

Ooooh, that's a big fat bright image. Lovely.

Cheers Dave, fat man - fat nebula

Originally Posted by richardo

Ah Mike, this is just lovely!!
Great to get the detail and signal in so fast... aint it!!
Love the palette choice.... just what this area needs I reckon.
When I've imaged it, it always look very flat with BB filters, even with Ha thrown in...

I too love the small stars that the NB has brought to the image and I also like the bubble/ halos about the brighter stars.. i think it's a non issue.

For 160' worth of data.... this is very smooth and detailed!.

As for the small issues.... hell, who needs 10' plus subs, fast reflectors will do great with less

All in all, lovely image mate... big congrats with the scope!!
Ps love that focuser.... I've got a new Feather touch coming in a few days... think this will solve my flex issues..(every thing else is rock solid but the ML) but I did price the PDF...then I quickly changed websites to a more affordable focuser
'If I had money, I'll tell ya what I'd do, I go down town and by a...... hell of a lot of very very expensive astro things

All the best for now
Rich

Thanks so much Richard, we are brothers now ...must get that OAG though, imagine 20min subs with 12" at F3.8 under a dark sky...the mind boggles

Mike

[John Hothersall]

Thats a wonderfully rich image and would love to see Centaurus A given the AG treatment. Star halos come from the OIII which is Astronomiks worst offender for halos with mirror scopes, there new low reflection Ha filter was not as bad but the OIII showed little improvement.

Hopefully you'll have a good winter and an OAG will give you those long SII exposures some objects demand. Lodestars are difficult to get as SX seem to be struggling to supply so you'll need to reserve one with the Australian dealer (663AUD).

John.

[strongmanmike (Michael)]

Originally Posted by John Hothersall

Thats a wonderfully rich image and would love to see Centaurus A given the AG treatment. Star halos come from the OIII which is Astronomiks worst offender for halos with mirror scopes, there new low reflection Ha filter was not as bad but the OIII showed little improvement.

Hopefully you'll have a good winter and an OAG will give you those long SII exposures some objects demand. Lodestars are difficult to get as SX seem to be struggling to supply so you'll need to reserve one with the Australian dealer (663AUD).

John.

Cheers Johnny

Thanks for the compliments on the image, I'm getting there...
Thanks for the tip re the Loadstar ...I do have the SXV-H9 though and while a bit bigger in the body than the load star it is still pretty small so I am hoping it will be suitable - much better little camera

Mike

[sjastro]

Very fine image Mike.

Steven

[gregbradley]

I wonder if there is a way to tell if you need to space it further out or closer in? Perhaps CCD Inspector
Greg