Your thought process to target selection

[matt-c]

Just a bit of curiosity about how you pick your targets for those big multi hour mosaic type pictures I see on this forum. 

I'm still an extreme novice but have recently started making a few lists of things I'd like to pick out in the year to come instead of my normal set up and......... "I'll try this" attitude which has seen me waste the few clear nights we get. 

How do you personally go about deciding? Do you browse the forums and see what's being imaged?  Maybe try something very difficult that is rarely done?  Or is just an impulsive I haven't done that why not type? 

Just a bit of fun to see people's thought processes while the cloud is thick

 

[PhotoGav]

I keep a list in Notes on my iPhone of targets, organised month by month, constellation by constellation, with best equipment to use. As I see an image that interests me, whether in posts on here, magazines, talks, tv programmes or wherever, I can add the target to that list to investigate further later. Then it's on to the good old Internet to see what exists already and to decide whether it is worth pursuing and how. Unfortunately the list seems to grow far quicker than I have sky time for!

When it comes to imaging time, using the target list and Sky Safari, I know what I will be imaging so that precious sky time can be taken full advantage of. I'm in my early days of imaging so I haven't exhausted the known, or at least familiar, universe quite yet! After that I guess the challenge is to start searching for my 'Squid'....... I may be some time!

[Sp@ce_d]

When you first start out it's a case of see how many targets I can bag in one night. As you progress you cut your teeth on the usual targets (and there's a very good reason why they are the usual targets). Then you start to think a bit more about what your sky conditions will allow you and how much time the target will require etc. I prefer targets that appeal to my eye and will be accessible for a reasonable amount of time to have any hope with the weather & my remaining life expectancy of getting enough data to do it justice! For instance I have never imaged the Orion Neb from my Obsy as its a bit low so I get limited time.. the surrounding trees have reduced this over the years and I never found it looks quite "real" and appealing to my eye anyway. Now I do look at what others are imaging.. I do look in the mags, books and trawl online. I do try and find something different or try and find a different "angle" of a familiar target.. a different focal length perhaps. Some nights it's just impulsive and "what can I find in the part of the sky not clouded out" just to get that frustration "fix". But these days it's searching for something different. There's a target I've been trying to master over the past couple of years that I've never seen portrayed or specific detail in the way I see or envisage it. I've actually bought scopes & equipment specifically to try and capture this and yet it still remains elusive to me in the amount of data I've been able to get and my processing skills to bring out what I wanted to see... sometimes the data just isn't there or my sky won't support it. At this point I think there's a big (and possibly expensive) decision to make about searching for better skies, finding something else or loosing the Mojo... Hmm that suddenly didn't become the "just a bit of fun" thread there... did it... whoops.

[ollypenrice]

I live in fear and dread of my co-conspirator, Tom O'Donoghue, sending me emails like, 'I've a great idea for a mosaic. Cygnus and Cepheus. Seventy six panels. Ha LRGB. 12 hours per panel. We could finish it in nine years.' So part of my mosaic planning involves locking Tom down into projects I might see finished, bearing in mind that I'm already 63...

My thinking on mosaics is to bring together objects which are not normally seen together. We often see the Heart and Soul, but why not the Soul and something else?

Or the Monkey, Jellyfish and M35:

I just cruise around that part of the sky rising in the east, or circumpolar, on a planetarium with my FOV frame on display and see what can be combined with what.

Or I look for wide structures, usually Ha in the Milky Way, on published camera lens images.

We can't take on the professionals in terms of resolution but there are still widefields to be had in more detail than ever before.

Olly

[martin_h]

Quite often my mosaics start as a single object, then I notice something on the edge of the frame or tucked into a corner, and so the mosaic comes to life, chasing the stuff that always seems to be just on the edge.

[Sp@ce_d]

Interesting that Mosaics.. have come up.. Until I got the QSI I wasn't interested in mosaics. I guess even with my collection (3) of 314's & scopes I regarded it as a chip size too far to cover enough sky in the available time... However, from the first sub I saw come in with the larger chip I started doing mosaics because it suddenly seemed just possible to capture those vast areas. Weird, you'd have thought it would have been the other way around. And... I know exactly what you mean about not wanting to stop at the edge & keep going... I now understand Ollys addiction (took a while)... the only problem is I like to "zoom" in as well so going ultra widefield & loosing "resolution" doesn't satisfy me either... :(... think I'm doomed with my skies

[Uranium235]

I normally choose my target by first thinking "do I have enough time?", becuase if its already past the meridian when it gets dark then you youre only going to get a few hours before its too low. Another factor is the Moon, will it get in the way? Sometimes its the sky - one half can remain cloudy, the other can be clear.

Of course there will be goals that you set for yourself... "must have" images which are only available as mosaics, like the Orion belt to sword, the Cygnus loop, or my current project - the Virgo supercluster. My main aim on that project is to reach 1000 galaxies, im just shy of 400 at the moment across six panes - so another six panes along with some seriously mind-bending searching and annoting should get me close. But, if I dont acheive that goal, I will just keep going until I run out of time and leave it until next year.

[ollypenrice]

13 hours ago, Sp@ce_d said:

Interesting that Mosaics.. have come up.. Until I got the QSI I wasn't interested in mosaics. I guess even with my collection (3) of 314's & scopes I regarded it as a chip size too far to cover enough sky in the available time... However, from the first sub I saw come in with the larger chip I started doing mosaics because it suddenly seemed just possible to capture those vast areas. Weird, you'd have thought it would have been the other way around. And... I know exactly what you mean about not wanting to stop at the edge & keep going... I now understand Ollys addiction (took a while)... the only problem is I like to "zoom" in as well so going ultra widefield & loosing "resolution" doesn't satisfy me either... :(... think I'm doomed with my skies

Exactly the same for us. Once you have a big chip, paradoxically, the world becomes your oyster and you think 'mosaic' more and more often. Our ultra-widefield rig is working at 3.5"P/P which is low resolution in the scheme of things. However, do a 6 panel mosaic of something and that final image is likely to be one of the highest resolution captures of that whole subject that is out there. In other words there's an intimate relationship between FOV and resolution.

In a chip size discussion a while back someone said that most targets are small. This is simply incorrect. It's an understandable perception arising from the fact that most fields of view are small so 'objects' become defined as targets which will fit on them. In fact the sky is full of enormous objects. I'm defining objects here as discrete structures created coherently by a single or a small number of processes. Think of Barnard's loop, or the Meissa nebulosity forming the head of Orion. (This nebula visually dwarfs the Veil, but it is surely one coherent structure, apparently being swept by some kind of wind or shockwave coming in from the right in this image.

The Meissa Nebula covers about 8x8 degrees of sky, compared with the Veil at a little over 3x3 degrees. There are also huge structures in Cygnus, centred roughly on Sadr - continuous loops of Ha. These are all 'objects' and because they are not often imaged as discrete objects, I think they're particularly fascinating.

Lawks, I hope Tom isn't reading this!!!

Olly

PS I've been thinking about how to present the best of both worlds in terms of wide view and close up. One format which came to mind was this one.

[matt-c]

Thanks for sharing it's gave me a lot to think about and nice to see people's methods.  

I'm slowly getting together a decent imaging rig and I think mosaics are my next port of call  

I struggle a lot as I'm limited to narrowband due to the extremely bad sky I have,  however I'm thinking of a (biggish project)  Ha mosaic of Cygnus (maybe more) even bi colour if it's present. My thinking is I can image the milky way from my garden something I definitely do not see. 

Maybe I can find a partner in crime in a dark location to provide the broadband.... Or sell up and move to Chile. 

 

[martin_h]

17 hours ago, matt-c said:

I'm slowly getting together a decent imaging rig and I think mosaics are my next port of call  

I struggle a lot as I'm limited to narrowband due to the extremely bad sky I have,  however I'm thinking of a (biggish project)  Ha mosaic of Cygnus (maybe more) 

 

Good luck with that.... 1st image showing some of the unprocessed panels, 2nd image - the story so far, 3rd image individual folders containing the subs for each panel....62 panes and its still not finished!

p.s. I started with the Crescent and got carried away!!!

[ollypenrice]

Martin, you have some stunning large scale structures there, rarely seen. Magnificent stuff.

17 hours ago, matt-c said:

Thanks for sharing it's gave me a lot to think about and nice to see people's methods.  

I'm slowly getting together a decent imaging rig and I think mosaics are my next port of call  

I struggle a lot as I'm limited to narrowband due to the extremely bad sky I have,  however I'm thinking of a (biggish project)  Ha mosaic of Cygnus (maybe more) even bi colour if it's present. My thinking is I can image the milky way from my garden something I definitely do not see. 

Maybe I can find a partner in crime in a dark location to provide the broadband.... Or sell up and move to Chile. 

 

NB mosaics are much, much easier than full colour. You don't get the gradients or the acute sensitivity to transparency in terms of star size. Effects of LP are cut by an order of magnitude. Also - and this is the best bit of all - the big structures are predominantly in Ha.

Olly

[matt-c]

That................................................Is incredible martin!!!

I can see why you didn't stop at the crescent its a total smorgasbord of Ha.

Why have i gazed upon this   I was content with the sadr region then i realised well the crescent is just there........and the north american...... dangerous stuff haha.

i look forward to your entire map of the sky.

 

[matt-c]

6 minutes ago, ollypenrice said:

Martin, you have some stunning large scale structures there, rarely seen. Magnificent stuff.

NB mosaics are much, much easier than full colour. You don't get the gradients or the acute sensitivity to transparency in terms of star size. Effects of LP are cut by an order of magnitude. Also - and this is the best bit of all - the big structures are predominantly in Ha.

Olly

That's great to know olly, if only I could get broadband star colours  

I'm extremely excited for 2016 to be cloud free  

[ollypenrice]

14 minutes ago, matt-c said:

That's great to know olly, if only I could get broadband star colours  

I'm extremely excited for 2016 to be cloud free  

What you could do is shoot very short RGB and, rather than trying to surgically replace the NB stars, just add the NB to the RGB in Blend Mode Lighten, totally overwhelming everything but the stars.

Olly

[swag72]

24 minutes ago, matt-c said:

That's great to know olly, if only I could get broadband star colours  
 

Having done one or two narrowbands mosaics (nothing like Martins!) I have found that sometimes with Ha and OIII you can get star colour showing through ..... I don't know how or why, but on a couple of images in particular that are just bi colour the stars have ended up looking like a pretty natural colour.

[matt-c]

interesting, for some reason I thought RBG was off the cards with bad sky quality? but if I'm understanding you correctly the plan is to shoot subs short enough to gather stars only and no real data? combine then add the narrowband to take over the nebulosity while retaining the stars?

That's very promising if that's "all" I have to do for good stars  

thanks olly

[matt-c]

Just now, swag72 said:

Having done one or two narrowbands mosaics (nothing like Martins!) I have found that sometimes with Ha and OIII you can get star colour showing through ..... I don't know how or why, but on a couple of images in particular that are just bi colour the stars have ended up looking like a pretty natural colour.

even better, thanks sara. Big fan of your narrowband stuff

[martin_h]

If I want to add RGB stars to my narrowband images I just shoot 2 minuet subs and just get enough to combat noise, 20mins ish per channel.

[matt-c]

5 hours ago, martin_h said:

If I want to add RGB stars to my narrowband images I just shoot 2 minuet subs and just get enough to combat noise, 20mins ish per channel.

Thanks for that martin, I think I'll have to take the plunge and get some rgb filters.

2 mins should be doable even in my skies.

[SonnyE]

You presume I actually think, plot, and plan. I don't really.

I use Stellarium as my finding/targeting program. Some of my objects I revisit, some are new to me. My particular fondness is Nebulae. I blame The Great Orion Nebula for my affliction with the night skies. It was my first actual find, with a 60x spotting scope on a tripod. After a short debate with my logic about pursuing Astrophotography, I began my slide down the slippery slope into my equipment collection. Which is fairly specialized towards my purpose of gathering pictures.

Often I will just find something interesting, do my alignment, then set up PHD in the area I think I will be imaging in. Or just pick after alignment. But I don't list, or plan much. And I don't pop about. I find myself on one target, then work on my imaging of it. Sometimes over a few nights. I have no need to acquire vast numbers of unverifiable targets over a night of viewing. I just want some of the best pictures I can get. Ones that I know are really done my way.

I like these targets that I cannot see without taking a shot in the dark and seeing what I get after many minutes of exposure. Testing my equipment and my ability to use it, and trying to get more out of it than expected. I'm glad I'm alive and engaged where the cutting edge of EAA and the fine targeting is available to enable deep space exploration by a common man such as myself. Yesterday is history, tomorrow is a mystery, and today is a gift. That's why it's call the Present.

Less Planning = Less Disappointments. More surprises = more fun.

But then, I'm weird.

[theastrodragon]

On ‎26‎/‎03‎/‎2016 at 16:52, matt-c said:

interesting, for some reason I thought RBG was off the cards with bad sky quality? but if I'm understanding you correctly the plan is to shoot subs short enough to gather stars only and no real data? combine then add the narrowband to take over the nebulosity while retaining the stars?

That's very promising if that's "all" I have to do for good stars  

thanks olly

How bad is your sky?

It's surprising how bad it can get before you cant do RGB, even though it will require more processing.