RGB IC63

[peter shah]

I managed to image this on in one night, IC63 and Gamma Cass. RGB only a four and a half hours total exposure 90mins in each filter.

cheers

Peter

[perfrej]

Nice and crisp! Add a few more hours and you'll lose the satellite trails in sigma rejection The number of stars is astonishing!

/per

[Stargazer33]

Nice and crisp! Add a few more hours and you'll lose the satellite trails in sigma rejection The number of stars is astonishing!

/per

I think that's the defraction spike from gamma cass. Not seen ones that long before. Very busy neighbourhood - light pollution must be terrible with all those stars!

Great image Peter - love the way you've managed to keep the star colours.

[bobmoss]

Very nice!

[peter shah]

Nice and crisp! Add a few more hours and you'll lose the satellite trails in sigma rejection The number of stars is astonishing!

/per

I think that's the defraction spike from gamma cass. Not seen ones that long before. Very busy neighbourhood - light pollution must be terrible with all those stars!

Great image Peter - love the way you've managed to keep the star colours.

spot on ...One of the characteristics of the AG12 it very straight clean diffraction spikes, on Gamma Cass over a 10min sub they become very long, if I was to push the process further you would be able to see them right at the edge of the frame

[Mr Bergman]

Very nice image!

[StuartJPP]

I like that, don't think I have seen it before. Thanks for posting.

[lensman57]

Very beautiful, your control of the killer star is amazing.

A.G

[Pete Presland]

excellent image, lovely star colours to go with nebulosity, why are the defraction spikes so large with the AG12?

[perfrej]

Right! Not used to spikes myself Refractors and a Maksutov-Newton

/p

[peter shah]

Thanks everyone

excellent image, lovely star colours to go with nebulosity, why are the defraction spikes so large with the AG12?

The  spikes obviously come from the spider on the scope. On the AG12 they are machined out of a single piece of Aluminium and because they need to be strong enough to hold the weight of the secondary without flexing the thinnest they can make them is 5mm (which seems to be  the industry standard when it comes down to CNC machined spiders) The Thicker the spider the brighter the diffraction spike. Also the brightness of the star is one of the main factors and Gamma Cass is one of the brightest stars in the sky making up part of a main constellation.. you quite often see double spike on some scopes, that's due to the misalignment of the spider's spokes with relation to each other. On some scopes you get a nice straight spike that fans out towards the end this is usually caused by poor coma correction, the F/ ratio is also a factor where this is concerned.

[davew]

That's quite spectacular for RGB only. The " Leading edges " are a lovely red of course but look at all that reflected blue !

And it goes without saying the star colours are magnificent again,

Dave.

[NOMH]

Great job on a tough target.

JB

[Dave_D]

 you quite often see double spike on some scopes, that's due to the misalignment of the spider's spokes with relation to each other. 

Great pic Peter...

I have the double spike problem. Is this what you mean? (ignore the vertical spike, i get that from a neighbours bathroom light they never turn off)

Hopefully, the (yet another) mod i did yesterday to realign the spider will have fixed it. Tonights session will tell if i succeeded

Not too worried either way though because as soon as the move to my new flat is finished, i'm dumping the paper thin OO tube, shoddy spider and wonky primary cell and building a serrurier truss

[peter shah]

Great pic Peter...

I have the double spike problem. Is this what you mean? (ignore the vertical spike, i get that from a neighbours bathroom light they never turn off)

Hopefully, the (yet another) mod i did yesterday to realign the spider will have fixed it. Tonights session will tell if i succeeded

Not too worried either way though because as soon as the move to my new flat is finished, i'm dumping the paper thin OO tube, shoddy spider and wonky primary cell and building a serrurier truss

That's it exactly ....its very difficult to align the spider vanes when they are very thin, the tiniest misalignment and you will get this problem. The best thing to do is to fit a cardboard spider mask over the thin vanes but instead of making four make two  that run right across the diameter of the tube. It will make the diffraction spike brighter but it will also stop them from splitting. That vertical  spike isn't from an off axis light source but something inside the optical train Its a case of going over everything one by, it might even be caused from the edge of the tube or even the draw tube sitting too far in the tube, to be honest it could be coming from a number of places. BTW nice image

[Dave_D]

30 second test on gamma cass... much better methinks. not perfect but the arms on this spider really are a pile of doo-doo

[Dave_D]

i'm having a crack at IC63 at the moment... should be a laugh comparing the two

a new (and desparately needed) mount is once again on my santa list but  i won't hold my breath as usual lol

[peter shah]

i'm having a crack at IC63 at the moment... should be a laugh comparing the two

a new (and desparately needed) mount is once again on my santa list but  i won't hold my breath as usual lol

I hope Santa brings you what you want....Im sure you are not giving yourself enough credit, Ill look out for your shot of 63,....BTW you have managed to improve the look of your spikes

[Gina]

Your technique and processing seem great Peter   Unfortunately, let down by your scope.  If you could run to a second hand MakNewt like the MN190 (190MN) all your spike problems are solved

[Dave_D]

I hope Santa brings you what you want....Im sure you are not giving yourself enough credit, Ill look out for your shot of 63,....BTW you have managed to improve the look of your spikes

yeah reasonably pleased with the fix. a new spider is needed to be honest but that's for another day.

[Dave_D]

here's a very quick poke and prod with last nights data... no comparison but it's mine, so i don't give a monkeys  i'll have another bash at it when i'm not putting laminate floor down.

and yeah, i know gamma cass is a bit OTT

2 hours 30 minutes of 240s subs plus a few darks thrown in.... moon really didn't help though.

[peter shah]

here's a very quick poke and prod with last nights data... no comparison but it's mine, so i don't give a monkeys  i'll have another bash at it when i'm not putting laminate floor down.

and yeah, i know gamma cass is a bit OTT

2 hours 30 minutes of 240s subs plus a few darks thrown in.... moon really didn't help though.

A great result and you have good control of Gamma Cass

Your technique and processing seem great Peter   Unfortunately, let down by your scope.  If you could run to a second hand MakNewt like the MN190 (190MN) all your spike problems are solved

Thanks Gina....didnt say my spikes were a problem  I like them

[Gina]

Oh well, to each his own

[Coco]

I managed to image this on in one night, IC63 and Gamma Cass. RGB only a four and a half hours total exposure 90mins in each filter.

cheers

Peter

Back to the original image..

Wow... thats very nice indeed Peter, love the colours.. 

[MikeODay]

Wonderful image Peter. Great colour in the stars and very nice detail and separation in the nebula.

Do you know what causes the repeated rings around the bright star in your image? I first noticed them in an image I made of the Horsehead Nebula with Alnitak in the centre (posted yesterday). I thought it might be repeated reflection of the secondary but in your image Gamma Cass is off centre.

Cheers

Mike