Southern Cross Mosaic

[EddieT]

Hi all,
I spent an awful lot of time on this one and should probably have waited until the conditions were better. I think I definately need a better site!

This is a 15-part mosaic (2 hours each) of the Southern Cross taken with a Tak FSQ106ED at f3.7 and QHY8 riding on an EQ6 PRO. Over a dozen nights of imaging between terrible and mediocre conditions over March/April 2009.

No web page for it yet, but here are some links to various sizes.

(800x740) http://astroshed.com/fsq106ed/crux-s.jpg
(1500x1388) http://astroshed.com/fsq106ed/crux-m.jpg
(2000x1850) http://astroshed.com/fsq106ed/crux-l.jpg

So many stars!

All the best
Eddie Trimarchi
http://astroshed.com

[h0ughy]

none the less it is a fine image - like the dust

[Hagar]

Looks very nice Eddie. Looking at trying to do some imaging lik this myself. I now have my FSQ, redcer and extender but now have to get the processing skills required. I doubt I will be playing with mosaics for some time. Lots to learn.

Nice one.

[EddieT]

Thanks Houghy. It's an interesting area and difficult to get detail in the dust. At least for me! What I like about it is the sheer number of background stars in the context of the constellation. Shorter f.l. images usually don't resolve these, and they showup as more of a general glowing area. With the stars resolved, it seems to get much harder to see the darker regions.

[EddieT]

Thanks Doug. You'll enjoy your FSQ, its a really nice little scope. When you get the hang of imaging with it, mosaics are a great way to widen your coverage and do your head in! Images quickly become huge, needing a beefy computer to handle things....

The results are worthwhile though!

[Octane]

Eddie,

Astonishing amount of detail through the Coal Sack.

Another excellent image, but we expect that of you. :)

Regards,
Humayun

[h0ughy]

now there is an idea you have put into my head. I am talking to a heap of school kids on tuesday and this would make a fine example of showing what an area looks like close up sequencing in from a "coal sack" dark area from a widefield 18mm shot to an awe inspiring area not devoid of stars but full of them. Smart man you are Mr T;)

the interesting part to me is the fact there are so many stars -and as you say resolved to pinpoint areas of light rather than a glow.

i also note your using a eq6 - didn't you have a g11? :shrug:

[EddieT]

Thanks Humayun!

[EddieT]

That sounds like a great example Houghy! Me smart ? I thought it was your idea! :)

Yes indeed. When I was planning the image, I actually took a couple of areas as 6 hour images, when trying to determine the necessary exposure times. Believe it or not, there was little added benefit in going from 2 hours to 6 hours. The SNR was higher, but there was very little extra detail visible. That's why I settled on 2 hours for each image.

[/quote]

I sold the G11 about 3 years ago and had a Paramount for a couple of years. I sold the Paramount about a year ago and bought an EQ6 Pro.

I catch up with my old G11 at astrofest and you may have seen it too, in the hands of Greg Bock for the last two astrofests!

[telecasterguru]

Eddie,

Beautiful image and processed to perfection.

The mosaics really add another dimension to imaging and give a very different perspective.

Frank

[EddieT]

Thanks Frank!
If I could have my way, I think I'd mosaic the entire sky. Only one lifetime wouldn't be enough! :)

[jase]

Nice work Eddie. Composition appears somewhat symbolic that is easy to associate with. Smooth transition between the panels and lovely colours. I particularly enjoyed how the jewel box is nested amongst the vastness of the star field - has a dramatic feel to it. A visual feast to the eye. Well done.

[Tamtarn]

The first word that comes to mind is "magical"

The stars look real with a lovely glow and the jewel box well resolved as well as the coal sack detail.

Have to agree with Frank - processed to perfection Eddie :thumbsup:

D & B

[Les Tilly]

Splendid Capture I am loving the widefield shots Great Job capturing and processing

Les

[EddieT]

Thanks Jase,
Some of the panels were incredibly difficult to balance. Though I tried to stay as close to new moon as possible a couple were taken during the gibbous phase which introduced some pretty bad gradients. Some were also taken when the frame was either entering or exiting the Surfers light dome, which made things even more difficult later. Due to time constraints (it was planned to be my main CWAS entry), I had to take what I could get. Turns out I did win something with it, I'm guessing an honourable mention...Will know for sure in a couple of weeks!

I read your comments on your Rho mosaic (messy? Not that I can see :) ), well I feel the same way about this. I spent a month processing it and can still see some issues plain as day, whenever I look at it. That's what comes of intimately knowing the image I suppose! Needless to say, I'm still working on it. Obsessive Compulsive ? You bet!

[EddieT]

Thanks David and Barb! Being our national asterism, I think it deserves an in-depth look and I'm glad you like it.

[EddieT]

Thanks Les!

[Paul Haese]

Lovely image Eddie. This is the first mosaic I have seen that I cannot see the join lines. An example of this is the 'centre of the galaxy' image that Rob Gendler got an APOD (I often wonder about the selection criteria for that site) for and it had join lines all the way through it. It was obvious on a HD panel. too many people are still processing on CRT screens and it shows all the time. So for me this is a far better image. I often see join lines but not on this occasion. Congrats.

[EddieT]

Thanks Paul!

Many thanks. The issues I mentioned earlier are by no means limited to me, and would be experienced by anyone doing a mosaic over multiple nights. Though light pollution certainly makes it harder in terms of background brightness and colour variations. I spent a great deal of time balancing not just the overal brightness, but balancing the darks, mids and lights for each RGB colour in each frame. A lot of work, but essential I think. And it pays off in the end.


Yes I do everything on LCD screens these days. I only tossed my secondary Sony Trinitron CRT last week. When it comes to public displays (like web presentations) I think you have to go with what the majority of viewers are using. But LCDs certainly make it difficult when processing for printing. Even though everything here is calibrated and profiled (printer and monitors), the LCD monitors are still way too bright for my liking, so printing still involves some trial and error. Colours are great and accurate, but brightness is troublesome. I actually processed two completely different versions of this mosaic. One for printing and one for screen display using the appropriate profiles for each.

Many thanks for your comments!

[Octane]

I can even see Gum45 and Gum46, clearly. This is so awesome, Eddie. :)

Regards,
Humayun

[gregbradley]

Super image Eddie.

You worked hard there. A QHY8 is small chip camera for that
sort of work.

I did a similar mosaic a year ago using a FSQ106ED aand reducer
with the Apogee U16M (16803 chip) and for a similar area (yours is a tad larger) it only took 4 panels.

The reducer for the 106ED is one of the best aspects of that scope.

Greg.

[cookie8]

Fantastic. So many stars:eyepop: ,so much effort!!! :thumbsup:

[Alchemy]

nice eddie, seamless integrating well done

clive

[EddieT]

Hi Humayun,
Yes indeed they are visible. Even more so at full size. The largest image posted is actually a quarter of the full size.

I'll post a deeper image of the Coalsack and Jewelbox soon where Gum46 is very clearly visible as well as some usually hidden features in the Coalsack. It's quite amazing whats lurking in the dust!

[EddieT]

Thanks Greg

It's more a case of using what I have. The QHY8 or the ST10XE....
Well yes, I would probably use a U16 if I had one...Would you swap it for an ST10 ? :)

I agree, it's great to get that extra field and speed. I haven't used my FSQ without the reducer yet, and I'm not planning to for a while!

All the best

[EddieT]

Thanks Vincent and Clive both!