All Classic Atlas charts label named stars, and many label all the stars with major catalog IDs -- ones with either a name or a conventional star chart label such as Bayer (Greek letter), Flamsteed (numeric) or variable star (such as R CrB). Also, all Classic Atlas charts show 220 major deep-sky objects (Messier + Caldwell) regardless of magnitude, plus more depending on the deep-sky object (DSO) magnitude.
The charts that use both the HYG and Tycho-2 catalogs have several other categories of stars
labeled by default:
Charts with a horizontal orientation are wider than they are tall, and generally need larger image sizes (pixel counts) to look uncluttered, compared to vertically-oriented charts. Suggested sizes are 1500 or more pixels for horizontally oriented charts and 1000-1500 for vertically oriented ones.
| Atlas | Catalog | Star labels | Star motions | Magnitude limits | Scale and Orientation | Remarks |
|---|---|---|---|---|---|---|
| Cambridge | HYG | Named only | No | +6.5 stars +9.0 DSO |
0.65 Horizontal |
Widest field of view. |
| Norton's Star Atlas | HYG | Named only | No | +6.5 stars +8.0 DSO |
0.75 Vertical |
Projection is similar to the equatorial charts in the print version; much narrower than other charts. |
| Sky Atlas 2000 | HYG | All Major IDs | No | +8.5 stars +10.0 DSO |
1.0 Horizontal |
Similar to a completely unfolded page in the print version. |
| Uranometria - 1st Ed. | HYG + Tycho2 | All Major IDs | Yes * | +10.0 stars +13.0 DSO |
5.5 Vertical |
Similar to a single chart (one page) in the print version. |
| Uranometria - 2nd Ed. (2000.0) | HYG + Tycho2 | All Major IDs | Yes * | +10.0 stars +13.0 DSO |
3.0 Horizontal |
Similar to 2 adjacent pages in the print version. |
| Millennium Star Atlas | HYG + Tycho2 | All Major IDs | Yes | +11.5 stars +15.0 DSO |
10.0 Vertical |
Similar to a single page in the print version. This is the most detailed chart, and can take several seconds to plot. |
* Stellar motions are available in Uranometria, but by default are not shown when the chart is first loaded. Click the 'Stellar motions' checkbox to display them. In charts where they are not normally available, they can be enabled through the Advanced Chart Settings.