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MartinMeredith
April 25th, 2015, 05:33 PM
First, hello to fellow lovers of the deep sky!

Although I've been primarily a visual observer (18" dob) in the past, nowadays I'm mainly into "assisted" observing using an 8" Newt and the very sensitive Lodestar X2 guide camera. But my interest remains the same: detecting faint objects rather than astrophotography, so I find this forum inspirational as well as the fabulous observing guides produced by some of its members.

Motivated by the need for an atlas capable of showing what I can routinely capture in sub-1 minute exposures with the 8" from a SQM 19-20 site, I've been developing from the ground up a set of detailed sky charts whose aim is to be complete down to at least mag 18. Some of you visual guys with huge scopes might conceivably find them useful, hence this post.

The charts use PPMXL and XHIP for stars and LEDA for galaxies, and in addition plot recent catalogues of open/globular clusters, bright, dark, reflection and planetary nebulae, variables (AAVSO), multiples (WDS), quasars (Veron) and galaxy groups/systems (Hickson, Shakhbazian, Palomar, Abell, VV, Arp, Arp-Madore).

When complete, there will be all-sky coverage via 6787 deep charts each covering 3 degrees of declination, along with 324 finder charts to enable rapid location of the relevant deep charts. The charts are vector-graphics PDFs designed to be zoomed to the limit to see all the information contained in them, and are all hyperlinked for ease of navigation. They're meant to be used on a tablet or laptop under any OS.

Currently, nearly 2000 deep charts are available for downloading, covering the following constellations: UMI LEO COM CRB CRT CRV CVN UMA VIR DRA BOO SER1 LIB HYA SEX LMI HER CAM. More will come in the next release when I resolve the issue of star-rich constellations…

Here's an example chart from Draco.

1618

The development is being documented on another forum so forgive me for not repeating all the information here (but of course feel free to ask questions on this current thread). You can find more about the motivation and catalogues here

A-deep-sky-atlas-for-electronically-assisted-observing (http://stargazerslounge.com/topic/239001-a-deep-sky-atlas-for-electronically-assisted-observing/?p=2591142)

and get hold of the charts via the dropbox links here (http://stargazerslounge.com/topic/242388-pretty-deep-maps-v02/?p=2631261)

Now all the infrastructure is in place it would not be too difficult to develop a set designed explictly for visual-only observers if there is sufficient interest. Do let me know if you have any suggestions for improvements.

cheers

Martin

Northern Spain

Dragan
April 25th, 2015, 08:45 PM
Martin!

Welcome to DSF. We're very glad you found us and decided to join.

First off, this is one exceptional undertaking! I've downloaded a few and am just perusing your charts. Exceptional!! The level of detail in the more congested areas of sky is great! I love the zoom feature of each PDF. This could prove very useful.

But I'm a bit perplexed. How do I use the finder charts to locate either a) an object or b) a constellation/region of sky?

Again, welcome! (I plan to add this to our UDSOR (http://www.deepskyforum.com/showthread.php?336-The-Ultimate-Deep-Sky-Observers-Resource)if you don't mind)

MartinMeredith
April 25th, 2015, 11:01 PM
Hi Dragan

Thanks for the welcome.

In practice you can start by opening any of the charts, either in the Finder directory or one of the constellation directories, and navigate to any other chart. If you're in a Finder level chart you get to the deeper charts by clicking on any of the grey chart numbers superimposed on the Finder. If you're in a deep chart, clicking anywhere in the chart takes you back to the Finder. Navigating from one chart to another at the same level is done by clicking any of the 4 chart margins (i.e. where the axes are). If any of this isn't working then if may be that you're using a pdf viewer that doesn't support hyperlinks (Acrobat does), or that the charts don't exist (because you haven't downloaded them), or because the charts are not at the same level in the directory structure. When you unzip the charts your directory structure has the Finder folder and the constellation folders at the same level

e.g. deepmaps/finder/... and deepmaps/VIR/..., where deepmaps is some folder.

You can also go straight to the constellation by clicking the 3 letter constellation code in the upper left of each chart. BTW If you don't see the grey chart numbers in the finder maps its because they don't yet exist for that constellation.

Finding a named object is not yet supported but very soon will be: I'll compile a large list of objects by type/constellation with hyperlinks to the relevant charts. Meanwhile, I find that using the search facility of the OS (in my case Spotlight on the Mac) is often enough to locate the object.

Let me know if this answers your question.

Yes, feel free to add to the UDSOR.

Cheers

Martin

MartinMeredith
December 3rd, 2015, 12:10 PM
A major revision of the atlas is now available.

Main changes (i) there is now an index for each type of object, filterable by constellation and sortable by any number of properties; this links directly to the chart containing the object; (ii) likewise, there are direct links to named catalogues (e.g. Shakhbazian) from the charts themselves; (iii) in star-dense parts of the sky I'm using an accurate stellar density representation (computed from PPMXL) which is sufficiently detailed to show dark nebulae outlines; (iv) for open and globular clusters the limiting magnitude is now typically 20; (v) finder charts and deep charts appear on the same page, making navigation a lot easier; (vi) all the sky is covered. What's still missing is some detailed documentation of how to interpret the information supplied with each object; I'm working on that and it should be there in a day or two.

http://tinyurl.com/prettydeepmaps

Martin

Don Pensack
December 10th, 2015, 09:43 PM
How does one go about reading the designations on each object?
I still couldn't read a lot of the labels with one square larger than my full-screen monitor.
How does one enlarge the object labels?

MartinMeredith
December 14th, 2015, 09:43 AM
Answered on this thread (http://www.cloudynights.com/topic/520286-a-new-atlas-of-the-deep-sky/).

Martin