diff --git a/docs/source/images/user_guide/object_details_01.png b/docs/source/images/user_guide/object_details_01.png index 59b263f6..77c5131e 100644 Binary files a/docs/source/images/user_guide/object_details_01.png and b/docs/source/images/user_guide/object_details_01.png differ diff --git a/docs/source/images/user_guide/object_details_02.png b/docs/source/images/user_guide/object_details_02.png index bede3081..31fdb7aa 100644 Binary files a/docs/source/images/user_guide/object_details_02.png and b/docs/source/images/user_guide/object_details_02.png differ diff --git a/docs/source/images/user_guide/object_details_03.png b/docs/source/images/user_guide/object_details_03.png index a76760ba..945524c0 100644 Binary files a/docs/source/images/user_guide/object_details_03.png and b/docs/source/images/user_guide/object_details_03.png differ diff --git a/docs/source/images/user_guide/object_details_contrast.png b/docs/source/images/user_guide/object_details_contrast.png new file mode 100644 index 00000000..c3270488 Binary files /dev/null and b/docs/source/images/user_guide/object_details_contrast.png differ diff --git a/docs/source/images/user_guide/object_details_notes_annotated.png b/docs/source/images/user_guide/object_details_notes_annotated.png new file mode 100644 index 00000000..1def78a9 Binary files /dev/null and b/docs/source/images/user_guide/object_details_notes_annotated.png differ diff --git a/docs/source/images/user_guide/object_details_pushto_annotated.png b/docs/source/images/user_guide/object_details_pushto_annotated.png new file mode 100644 index 00000000..280ad895 Binary files /dev/null and b/docs/source/images/user_guide/object_details_pushto_annotated.png differ diff --git a/docs/source/user_guide.rst b/docs/source/user_guide.rst index 7d2a82ae..8d52aed4 100644 --- a/docs/source/user_guide.rst +++ b/docs/source/user_guide.rst @@ -254,6 +254,10 @@ view, getting them below 0.25 (half the true field) should put the object in vie Closer to zero means more centered. For a very dim object, knowing it's dead center and consulting the object image can make all the difference. +The number in the upper right is the object's +:ref:`contrast reserve ` — an estimate of how easily it +should show in your eyepiece tonight. + .. image:: images/user_guide/object_details_02.png The PiFinder can display images of every object in its catalog. See the section on @@ -261,9 +265,70 @@ The PiFinder can display images of every object in its catalog. See the section .. image:: images/user_guide/object_details_03.png -Depending on the catalog, the PiFinder may have detailed notes along with Type, -constellation, magnitude, and size. Use the **+/-** keys to scroll the notes field. At -the bottom of the notes is a count of how many times you've logged this object. +Depending on the catalog, the PiFinder may have detailed notes alongside the object's type, +constellation, magnitude, and size — the size is shown in degrees, arcminutes, or arcseconds, +whichever best suits the object. Use the **+/-** keys to scroll the notes. + +Many objects carry more than one catalog designation, and the notes can gather a description +from each. A bright horizontal rule labelled with the catalog and number — for example +*NGC 6543* — sets one catalog's notes off from the next, so you can see at a glance where +each note comes from. The notes finish with a count of how many times you've logged the +object, marked by its own rule (it reads *Not Logged* until your first sighting). + +What each part of the screen shows +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The Object Details screen packs a lot in. These two views label every part — the Push-To +screen, and the catalog details you reach by pressing **SQUARE**: + +.. image:: images/user_guide/object_details_pushto_annotated.png + +.. image:: images/user_guide/object_details_notes_annotated.png + +Contrast Reserve +^^^^^^^^^^^^^^^^^ + +The number in the upper right of the Object Details screen is the **contrast reserve** — an +estimate of how easily an object should stand out in your eyepiece. It weighs the object's +brightness and size against your sky brightness, your telescope's aperture, and the +magnification of your active eyepiece, then compares the result to what the eye can detect. +A higher number means the object should be easier to see. + +.. image:: images/user_guide/object_details_contrast.png + +Keep pressing **SQUARE** to reach the Contrast Reserve page, which shows the value on its +own with a plain-language reading of what to expect: + +.. list-table:: + :header-rows: 1 + + * - Contrast reserve + - What to expect + * - Below −0.2 + - Object is not visible + * - −0.2 to 0.1 + - Questionable detection + * - 0.1 to 0.35 + - Difficult to see + * - 0.35 to 0.5 + - Quite difficult to see + * - 0.5 to 1.0 + - Easy to see + * - 1.0 and above + - Very easy to see + +The contrast reserve appears only when the PiFinder has everything it needs to work it out: +an active :ref:`telescope and eyepiece `, +a sky-brightness reading, and an object with a known magnitude and size. If any of these is +missing — a double star with no single magnitude, or before the camera has estimated the sky +brightness — the number is simply left off. + +.. note:: + The sky-brightness figure comes from the PiFinder's Sky Quality Meter (SQM), its + camera-based estimate of how dark your sky is, so the contrast reserve tracks your real + conditions: the same object reads higher under a dark sky than from town. Treat it as a + guide rather than a guarantee — averted vision, transparency, and how dark-adapted you + are all still play their part at the eyepiece. Filters ----------