Leave a Review Screen Ruler
Very useful for telescope collimation
Aligning mirrors on a Newtonian telescope can be tricky. Aligning the secondary mirror with the focuser is even harder without using an expensive concentric circle eyepiece, which I do not own. Using a collimation cap, I took a photo using my phone and used this app to check using the protractor tool - it’s easy to centre the overlay so the edge meets the focuser tube, then zoom in to check if the secondary is a) centred and b) circular. Easy!Show lessMeasures pixels between two points in an image
This exactly what I needed to measure the distance between two isobars on a weather map. Having the angle between the two points is neat.
One possible improvement would be to have a measure tool that returns distance (and angle) instead of reading off a ruler.????
I have no idea what the units of measurement are. Pixels? Mm? Certainly not cm or inches, which is what I was looking for. I wouldn’t have even thought to rate this if it hadn’t left me with such confusion. Any sort of labels would’ve changed this to no review, or even a four star. But I’m just confused. Which is disappointing.
At least you can upload images of your actually screen, which is more than I can say for the last app I tried. That’s keeping this from a one star.Show less