The batinov mask consists of three separate grids that produce three angled diffraction spikes when the telescope is pointed at a bright star. Although this homemade bahtinov mask can achieve perfect focus, it does. The bahtinov mask makes it easy to focus your dslr camera, ccd camera, or webcam when imaging the night sky. There are many methods, software and devices on the market but the bahtinov mask is the least expensive and is a very effective tool. From beginner telescopes to professional observatories, opt has it all. It is common practice to focus your camera dslr or astroccd on a bright star as this star and the object you want to image will both be at infinity so getting the star in focus will ensure that the deep. Improve your astrophotography focus with a bahtinov mask.
There are commercial solutions for knifeedge focusing. New bahtinov mask assistant tool indi forum indi library. Unlike a hartmann mask which provides no visual cues on the direction of travel needed for focusing, the spikea mask is a bahtinov mask which clearly shows the direction of travel needed to achieve focus. Once you get focus set correctly you do not want to lose it the. It allows achieving precise focus using a bahtinov mask making subpixel analysis of the spikes. The bahtinov mask the sky at night in digital images. Farpoint fp402 bahtinov focus mask for telescopes with dew shield or tube diameter from 5. Two programs which offer softwarebased bahtinov assistance are niels noordhoeks bathinov grabber and. Farpoint bahtinov mask for refractors or newtonians with 5. Always wondering about the curiosity of space and what answers. Farpoint bahtinov focus mask demonstration youtube. The slots are angled in such a way that they create a diffraction pattern with 3 spikes in an x when aimed at a point light source.
In 2008, pavel bahtinov, a russian amateur telescope maker and astronomer, published an ingenious new way to easily focus your dslr camera, webcam or. Focusing methods astrophotography by jerry lodriguss. Bahtinov mask the easiest way to achieve sharp focus. How to make bahtinov mask, pdf templates deepsky watch. This is the method i use to focus on stars with my telescope and dslr.
It requires the capability to acquire 640x480 images. Im running the 32bit version on a netbook, canon 300d camera and dslrfocus software for image capture. Unlike autofocus and star measuring software tools, this old school method can be done without the use of an external computer, and only takes a minute. The central spike moves left or right relative to the diagonal x spikes according to focus position. With the camera mounted to the telescope, i point the telescope to a bright star. Bahtinov grabber goes 64 bit and 32 bit update niels. Dear all, i have started to make a prototype for a bahtinov aid, which. Today, the most accurate method of focusing is with software metrics, but this requires a. No matter which type of camera you use, a bahtinov mask can help you achieve a higher level of accuracy when focusing your telescope or a camera lens. This farpoint bahtinov mask fits telescopes with outside diameters of between 5.
It would seem that the easiest way to focus is to just look through the viewfinder of the camera. Also when the problem occurs the mask angle is also shown incorrectly. At times when visually the focus looks correct the one of the overlayed lines shown in the software is way off and can jump between two places. Measure your diameter from the end of the tube or dew shield. Two of them form an x shape, and another spike crosses it, forming a shape. Telescope focus aids telescope focus masks high point. Kendrick bahtnov focus masks kendrick astro instruments. A bahtinov focusing mask in use on the front of the at6rc telescope the. Bahtinov mask for precision focusing, then remotely move it out of the path once focus is. This mask attaches to the front of the scopes objective lens to show the astronomer how to precisely focus their telescope. When precize focus is achieved the pattern becomes symmetrical. Three patterns were calculated for each of the masks, one in precise focus, one with 12 microns off focus, and one at 36 microns.
Also, a hartmann mask doesnt provide the precision of the spikea. The bahtinov aid uses licensed technology developed by neils noordhoek the very same technology built into the famous bahtinov grabber. Your quest for the perfect astrophotography focusing solution has ended. The bahtinov mask is probably the easiest product on the market to achieve tight focus for visual use and for digital astrophotographers. The bahtinov mask is a very elegant solution to one of the biggest problems that besets the deep sky astrophotographer focus. The bahtinov mask achieves perfect focus in seconds. Video demonstration of how to use a bahtinov focusing mask for astrophotography. I made a simple program that detects the three lines of the bahtinov pattern and tells you how far the central line is from the crossing of the diagonal lines.