Sight Marks Help

The Sight Marks Page allows you to save and edit any number of different sets of sight marks, and to get different estimates for all the standard distances from each set. For example you may want to keep a different set of sight marks for different arrows, or for different bows or other setups.

However if you only want to deal with one set of sight marks, that’s fine too.

Entering Sight Marks

To get started, dig out your notebook of sight marks and go to the first section Input Sight Marks. Click on the “Add a Sightmark” button and enter your first sight mark. Enter the distance with a “y” or “m” suffix, i.e. 20y or 30m.  The sight mark itself can have a decimal point, i.e. 80 or 94.5. You need to enter at least two sight marks to get an estimate. If you enter two sight marks you should see them in the Graph of … section, with a straight line through them. In the Estimates For … section below that you should see a table of estimates, based on the sight marks you’ve entered, for all the standard metric and imperial distances.

The graph will show your imperial sightmarks as white circles, and your metric sightmarks as yellow.

If you’re only entering two sight marks, then the wider apart they are in terms of distance the better: if you enter only a sightmark for 15y and 20y then obviously the estimate for 100y could be way off.

If you enter three or more sight marks, it is unlikely that the graph will be able to draw a straight line through all of them. Instead it works out the line that best fits the values you have given it. This is the line used to calculate the estimates. The graph is useful because it can show you which of your input sight marks are most “off” and might need reconsidering. The more sight marks you enter, the more accurate the estimates are likely to be, provided your input sight marks are good.

If you make a mistake, or want to ignore a sight mark because it is obviously “off”, you can click on it in the input table then click the “Delete Selected Sightmark” button to delete it.

Saving and Deleting Sets of Sight Marks

When you are happy with your first set of sight marks, go to the Saved Sight Marks section and click the “Save” button. You will be prompted for a name to save them as. You may just want to save them as “Sightmarks”, or use a more descriptive title like “ACCs Outdoor, looser knocks”, whatever works for you. Once you have saved a set of sight marks, you will see it in the “Select” drop down. The various titles will change to show the name you chose, and when you return to the  page at a later date (on the same computer and browser) it will still be there.

Nothing is permanent until you save it, so if you are making changes and want to get back to your last saved set, click the “Restore” Button. If you click the “Delete” button it will delete the current set, without asking you for confirmation, and if you switch between different sets of saved sight marks you will lose un-saved changes, so do be a bit careful.

Printing Sight Marks

The Estimates For … section has a table showing the estimates for the current set of sight marks. There are a number of buttons for exporting various formats, however they don’t work in all browsers, (at least not in Safari, hopefully this will be fixed soon.) The “Print” button works; it hides everything on the page except the table so you can then print it. Hit the “esc” key after you have printed the page to un-hide everything again.


All of the data you enter is actually just being stored in your local browser. If you visit the Sightmarks page on another computer or with another browser you will have to enter the data again there. The only way this can be fixed is to give each club member an individual login account on the website. We may well do this in the near future, but for now the sightmarks page is usable as is.