diegop

Wow! Thanks a lot vlaiv, i am left speechless. I will try to understand everything and i'll write you back with doubts Best regards

Hello vlaiv, many thanks what an awesome answer. Much appreciated. I am a completly beginner in AP and i think that starting learning the basis should be the best. I have never use ImageJ and i have try to calculate such thing as this, but i want to learn I am just starting with what i have at home. Sorry but i am not already familiar with this concepts: plate scale sampling rate Telescope Refractor Skywatcher 102/1000 (i know is too slow for AP, i am using it to just start learning) Mount EQ3-2 helios skycan 2001 Camera Old compact camera Nikon coolpix l15 https://www.digicamdb.com/specs/nikon_coolpix-l15/ Focal length (35mm equiv.): 35 - 105 mm So the data i first need to know is: pixel scale (is it the same that plate scale?) Seems the Astrometry.net alternative should be more easy, i'll try first the astrometry.net method and then with ImageJ because i really would like to learn measure it with the imageJ. let's do it! Best

Hello All i wonder if is it possible to measure the deviation between two images in degrees. What i am trying to do is measuring the backslash of a telescope equatorial mount. I attach a digital camera and i take two pictures,i would like if i can measure the deviation between both images using imaging software (like imajeJ or another one). The camera is attached this way Best