### Overview The main objective of this program is to compare the target galaxy with a bunch of standard galaxies to find the inclination of the target galaxy. At each step, there is only one target galaxy which is displayed in a yellow panel. The inclinations of the other galaxies are known. All the standard galaxies are ordered based on their inclinations from left to right, with left galaxies having lower inclinations. User can only move the target galaxy using either the [controlling left/right arrow buttons](#lr_keys), or other methods, e.g. dragging the target panel from the middle row and replace it, or using 'A' and 'D' keys on keyboard. To estimate the inclination of each galaxy, user goes through two steps at most. In step A, the difference in the inclination of standard galaxies is 5 degrees. Once user narrows down the approximate location of the galaxy, (s)he has the chance to increase the measurement accuracy in step B, where the inclinations are 1 degree apart. Therefore, at the end we expect users to estimate the inclination of an unknown galaxy with the accuracy of ~1 degree. Inclinations smaller than 45 degrees (i.e. galaxies more face-on than 45 degrees) would be rejected and flagged automatically and they would not be used for the distance measurement analysis.
### General Features ![Demo](helpics/demo.png) Looking at the above image, numerical labels are as following: 1. Template row: This shows how galaxies are ordered (left and right correspond to face-on and edge-on respectively) 2. Middle row consists of 9 standard galaxies plus one target galaxy underlined in yellow 3. Bottom row displays a larger view of the target galaxy and its neighboring standard galaxies. This helps to make better comparisons in harder cases where inclinations are close to each other. This row and the middle row follow the same chain of commands. Thus, if user changes any panel in one of these rows, the other would be changed accordingly. 4. Target galaxy, visible in the middle and bottom row. Note the yellow color associated to this galaxy. 5. '<' and '>' buttons to move the target galaxy to the left or right. Instead, you can use 'A' and 'D' keys on keyboard. 6. Your user name and project ID. Clicking on this menu item would lead you to your personal profile. 7. It shows how many galaxies you have worked on versus the number of total galaxies (or your ultimate number). 8. Standard galaxies. They are labeled with their inclination numbers in ascending order from left to right. 9. The **SKIP** button helps you to skip working on the current galaxy and move to another galaxy chosen randomly. 10. The **NEXT** button finalizes your work, and either leads you to step B or to the report page.
### Moving the Target Galaxy ![Drag and Drop](helpics/drag_drop.png) + **Small Panels** (middle row): You can easily drag and drop the highlighted panel. + **Big Panels** (bottom row): You can either use *'A'* and *'D'* keys on your keyboard or left/right arrow buttons ![lr keys](helpics/lr_keys.png) under the highlighted panel to shift the target galaxy to the left/right. + *Ů”Note*: You can NOT drag any of the bottom panels. Drag-and-drop only works for the middle row panels. + If you put a target galaxy before a standard galaxy with the inclination less than 45°, it would be automatically rejected and flagged as a galaxy more face-on than 45°.
### Mouse and Keyboard Actions ![Mouse Actions](helpics/mouse_actions.png) + Mouse left button: **Selecting** a panel. Once a panel is selected, you can change its filter to any other SDSS *gri*-bands. + Mouse middle scroll wheel: once your mouse pointer is on any galaxy panel (middle or bottom row), you can re-size its image. ![arrow keys Up/Down](helpics/arrow_keys_ud.png) ![Zoom in/out](helpics/zoom_in_out.jpg) + You can perform zoom in/out actions on a *selected* panel by using up/down arrow keys. ![arrow keys Left/Right](helpics/arrow_keys_lr.png) ![Rotation log](helpics/rotation.png) + You can rotate a *selected* panel by using left/right arrow keys. Use this option if the semi-major axis of the galaxy is not perfectly aligned horizontally (i.e. along the x-axis of your screen). + You can use *'A'* and *'D'* keys on your keyboard to shift target galaxies to the right or left.
### Control Buttons ![Command Keys](helpics/command_keys.png) + **- sign** makes all the big panels invisible. This is useful if you are using small screens. Then you would see a **+ sign** which can be used to bring back all the big panels. + **PGC ###**: This buttons opens a side window that contains a colorful image of the target galaxy in an Aladin Lite panel. In the Aladin panel, you can pan the view by clicking and dragging. You may also use your mouse scroll wheel for zooming in/out. In addition, you have other options like changing the survey layout etc. For more information please consult with the Aladin help page. Also, you see other photometry information of the galaxy taken from Extra Galactic Distance Database (EDD). + **HI profile**: Displays the HI-21cm profile of the galaxy. The width of this line would be later used for distance measurements. In the case of non-rotating galaxies (e.g. ellipticals or irregulars), this profile looks noisy or anomalous. ![Shuffle Key](helpics/shuffle_key.png) + **Shuffle button**: This button replaces the standard galaxies with other standards with the same inclination values. This helps you to make sure the target galaxy is very well located relative to all standards. + Note bar: You can write any comments and notes about the target galaxy here. + **SKIP**: To skip working on the current galaxy. Another galaxy would be chosen randomly and displayed in the following window. + **NEXT**: It sends your result to the server and depending on the situation, it either finalizes your work on the current galaxy and gives you another random galaxy or advances to the following step.

Side Control Panel
![Selection Panel](helpics/selection_panel.png) ![Filter Panel](helpics/filter_panel.png)
+ **- sign**: Large portion of this control panel would be collapsed if you use this button. However you would see a **+ sign** to expand it again. + **⇅ sign**: This inverts the color of *ALL* panels. + **g/r/i/gri**: Use these buttons to display the images of all panels in different SDSS bands. **gri** displays composite colorful images based on g+r+i data. + **Trash bin**: Use it to reject a galaxy or flag it. To un-flag a galaxy you need to click on the trash bin logo again. + **Image Scaling Controller**: Use these to zoom in/out and rotate an image once it is **selected**. To select a panel, click on its image. + **PGC ###**: This shows the ID of the selected galaxy. If you click on this ID, a side window would display its image in Aladin Lite as well as its photometry status. + **Radio Buttons**: They show the current filter of the *selected* image. You can change the filter and press the **Load** button to change the *selected* image. To invert the *selected* image, use the **Invert** button.
![Step A](webpics/A.png) ![Step B](webpics/B.png) + **Step Indicators**: It takes 2 steps at most to find the inclination of each galaxy, based on which you see one of the above indicators (**left:** *step A* and **right:** *step B*). If you are on *step B* and you want to go back to the previous stage, you can click on the check-mark sign (✓). This way you can correct your mistake and choose another 5° category. ![Step A Button](helpics/step_A_button.png) When you are at *Step B*, you can also use this button to go back to *Step A*.

### Rejecting and Flagging ![Rejecting](helpics/trash.png) + At any step, clicking on the *trash bin* you can reject the galaxy. Rejected galaxies would not be used for distance measurement analysis. + To **cancel** your action, click on the trash bin again or use the cancel button. + It is advised to use at least one of these items to explain why you are rejecting a galaxy. * Not Sure, use b/a for inclination: If you are not sure that you are able to find the inclination of the galaxy, or you think we need to fit an ellipse and use its semi-minor to semi-major axis ration to estimate the inclination * Get a Better Image: If the image is not clear, or you don't see a faint galaxy, or in the case part of the image is missing due to artifacts and data reduction masks * Not a good TF Galaxy: This option is true for all rejected galaxies. If you think that for whatever reason a galaxy is not a good candidate for distance measurement using Tully-Fisher technique which works based on the correlation between rotation rate and absolute luminosity of the spiral galaxies. If you are only choosing this item, please leave a note. * Ambiguous, Confused: If the galaxy looks like a fuzzy patch, or it does not look like the other spirals. Note that some of the faint spirals might seem to be fuzzy and unclear, but they are just low surface brightness. Usually looking at the image of galaxy in other bands helps to make better judgments. * Disturbed, Tail and Trail: If the galaxy is under the influence of the other galaxies, or it is going through some interaction episodes. During such gravitational interactions, galaxies might have some anomalous features like gaseous tails and trails. * Bad HI Profile: If the HI profile is super noisy or not normal. * More Face-on than 45 degrees * Not Spiral: in the case of dealing with ellipticals and irregulars * Multiple: If you see other galaxies in the field of target galaxy where their size of companion is comparable to the original galaxy
### Report Page ![Report](helpics/report.png) + When you are done with a galaxy, the system automatically records the results in the data-base, and then it reports a summary. For whatever reasons if you think you need to cancel your action and work on the galaxy more, you can use the **Undo** button. If you think everything is good, you can continue your work by pressing the **NEXT** button. + You would also see how many galaxies out of your current list you have finished working on, and how many more you have left.
### Side Windows ![side windows](helpics/aladin.png) + A corresponding window pops up when you request to see the HI profile of the target galaxy or its image in Aladin Lite. + If these windows open up in new tabs in your browser, please drag them out and leave them side-by-side to your main working window. If you leave these external windows open, as you do the same request for the other galaxies these side windows would be refreshed. + In the photometry side pages (a.k.a the Aladin page, e.g. above picture), you have also access to other databases through a set of buttons. In more difficult cases it is worthwhile looking at *Pan-STARRS* images, if available. These images are available for galaxies with *-30°< Dec.*. Pan-STARRS images have higher resolution and are slightly deeper, therefore you may be able to see more details. However these images are not good enough for photometry and in some cases they are saturated at galaxies center. In these cases, you see that images have very big masks in these regions.
### Supported Browsers ![Browsers](helpics/browser-logos.jpeg) This GUI has been tested with these browsers: Google-Chrome, FireFox and Safari. All tests have been successful in the Microsoft Edge browser. However if you are using touch screen devices, the drag-and-drop features might response slower compared to when you are using a mouse. This totally depends on the hardware platform you are using. This GUI might not have its best performance on any other browsers.
![FAQ](helpics/faq.jpg) 1. **How to re-scale an image?** Please either use the middle mouse scroll wheel while the mouse pointer is on an image, or use the arrow keys on your keyboard once a panel is selected. Please read [Mouse and Keyboard Actions](#mouse_keyboard) and [Control Buttons](#ctrl_buttons) sections. 2. **I pressed the *Next* button and inserted a wrong inclination for a galaxy. What should I do?** Please use the *Undo* button on the [Report Page](#report_page) to reverse your action. This gives you another chance to work on the same galaxy. If you no longer have access to the *Undo* button for that specific galaxy, contact us with the ID of the galaxy and/or the approximate time you've been working on that. 3. **I see a big masked region over the galaxy. What is the best strategy in this case?** You can select the image and then use the [Side Control Panel](#side_ctrl) to switch to the other filters. In most cases the image may look better in other filters. Use the best filter for working on the galaxy. If none of the filters are good enough for your work and a big portion of the galaxy is missing, just reject the galaxy and move on. You can also leave some notes to help us assess the situation. Please read the [Rejecting and Flagging](#rejecting_flagging) for more information. 4. **I am going to leave the session and start working later, what's the process?** You can always remain signed-in. Just close the inclination tab/window. Please reload the page if you see the time-out message. Normally if your work-page is idle for 10 minutes, you are required to refresh the page and start working over on a new randomly chosen galaxy. So, it is better not to leave a page at *step B*, since due to the time-out reload process you will loose your work. 5. **How can I recover my forgotten password?** All registrations and authentication processes are done through the Google services system. Therefore, since we are not handling this part, we are not responsible for your lost password. Please try to recover your Google account password first and then proceed to login to our system. You can also use any other Google account you may have and continue working. If you are participating in a program that requires you to have a specific *Project ID*, please let us know your new Email address as well as your project ID.