A bahtinov mask creates diffraction spikes visible to the viewer, with each direction of slots in the mask corresponding to a spike. The gerd neumann bahtinov mask is of high quality and should last a long time with care. See image 6 this software analyzes the pattern created by the bahtinov mask and reports how far from perfect focus you are. This distance depends on the focal length of the objective and the distance between the objective and the subject. The center hole fits well over either the secondary mirror or a hyperstar attachment with a qhy10 camera attached. Aspikeaexample of the nowclassic bahtinov mask is shown in image1. Whether youre doing planetary visual observing, planetary imaging, or deep sky imaging, the bahtinov mask is a great accessory to get the best focus for your telescope quickly and easily. Three patterns were calculated for each of the masks, one in precise focus, one with 12 microns off focus, and one at 36 microns. Hartmann masks are cut either with circular or triangular holes. The central spike moves left or right relative to the diagonal x spikes according to focus position. The device used for recording the image be it traditional photoemulsion or digital sensor should.
Credit goes to russian amateur astronomer pavel bahtinov for making his idea available to the astronomy community. 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 sky object. I had the materials lying around, and after making it i was. Measure your diameter from the end of the tube or dew shield. The focus error was 300 microns, and the distance between the x. The bahtinov mask was invented by pavel bahtinov from russia. The batinov mask consists of three separate grids that produce three angled diffraction spikes when the telescope is pointed at a bright star. In 2008, pavel bahtinov, a russian amateur telescope maker and astronomer, published an ingenious new way to easily focus your dslr camera, webcam or ccd camera for astrophotography. There are many methods, software and devices on the market but the bahtinov mask is the least expensive and is a very effective tool.
Designing a mask using drawing, design, or cad software can be challenging, as the. Jun 23, 2017 a homemade bahtinov mask by reddit user ozvooky. For an sct, the secondary mirror has three adjustment screws. May 10, 2011 does a focus mask work for lunar imaging, so you focus on a star then pan across to the moon keeping the same focus. Select the farpoint fp410h version not this item for all new celestron scopes.
Therefore, the most obvious way to me is to have three bahtinov masks designed into the mask. Anyone who has ever taken a photograph knows the importance of focusing. Of the two i have come to prefer the full width half maximum fwhm feature of bye. Astromania bahtinov mask focusing mask for telescopes fm200mm for a tube outer diameter od from 215mm260mm can be mounted with the brass screws inside or outside the drawtube. Most if not all newer celestrons have fastar or they are fastar ready. When i tried it on my 14 inch, which was still settling down to ambient temperature, i could watch the centre line move as the focus changed with temperature. Also when the problem occurs the mask angle is also shown incorrectly. A bahtinov mask can help you achieve a sharp focus for your astrophotography images. It requires the capability to acquire 640x480 images. Bahtinov mask to focus on a star focusing tips youtube. Adjust the telescopes focus so that the central spike appears directly between the other two. Farpoint bahtinov focus mask for astrophotography manufacturer part number fp410. One mask is a general purpose mask designed to fit refractors and newtonian telescope. The telescope parameters were set to be a 10 at f4.
Simply place the bahtinov focus mask over the end of your telescope made in the usa by farpoint astro amazon warehouse. The mask will produce six long angled diffraction spikes on the star. This mask attaches to the front of the scopes objective lens to show the astronomer how to precisely focus their telescope. The spikea bahtinov mask is made from quality light weight aluminum and machined with precision tools, then anodized black to eliminate light reflection. Msc thesis student theses faculty of science and engineering. This shopping feature will continue to load items when the enter key is pressed.
Bahtinov focus mask for older classic celestron 8 sct without fastar or hyperstar. Continuing the discussion from focusing using bahtinov mask. Unlike autofocus and star measuring software tools, this old school method can be done without the use of an external computer, and only takes. To help get an accurate focus with my c11, a bahtinov mask was placed over the corrector lens. See and buy bahtinov focusing masks at our hertfordshire uk based showroom or buy online.
It provides an intuitive new way to simplify dslr, webcam or ccd camera focusing for. The bahtinov mask, invented in 2005 by a russian amateur astronomer, pavel bahtinov in 2005, is a device used to focus using a bright star. The image projected by the objective gets sharp at a certain distance behind the objective. But i cant get the mask to show the starshaped rays of light emanating from the star i. 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. Relativetothehartmannmask,the diffraction pattern created by the bahtinov mask allows for much more precise focus. The idea is to create a specific diffraction pattern so that you know if you image is in focus. Ive been having difficulty focusing to infinity with my canon 6d and samyang 14mm f2. They are named after paul bahtinov, who developed the first designs. A bahtinov mask is a focusing aid for astronomy in general, and astrophotography in particular. The spikea focusing mask astronomy technology today 61 the focus knob, the line will either move towards the center of the v or away from it. This process is an essential step of any deepsky astrophotography session. So i thought i would try a farpoint fp400 bahtinov focus mask to see if it would help me focus better.
I get focus on the moon by looking at a zoomed in image from my camera and rolling the focus back and forward to determine a range of best focus and then dropping the focus in the middle. Astromania bahtinov mask focusing mask for telescopes. Its an elaboration on the idea of a hartmann mask something you stick over the front end of your scope to induce a diffraction pattern that makes focusing. Dec 02, 2017 to 3d print the bahtinov mask as shown in the images above, i used opencad a free software and a readymade tweakable template or model called bahtinov mask generator modded which i found on. Carey focus masks use slits in two angles, 12 degrees on the left and 10 degrees on the right. A bahtinov mask is a musthave for every astrophotographer. Even the smallest possible deviation from perfect focus noticeably degrades image quality when zoomed in to 100%. I have looked into diy bahtinov mask but my hands are not steady enough to cut one. This focus mask type is the only one that does not use diffraction and are best suited for gross focus adjustments as smaller discrepancies can be difficult to detect. Also, a hartmann mask doesnt provide the precision of the spikea. Farpoint bahtinov masks are by far, the easiest, fastest and most consistent manual focusing aid available to the amateur astrophotographer. Im running the 32bit version on a netbook, canon 300d camera and dslrfocus software for image capture. The spikea mask will last you for a lifetime of imaging. It can be used alone or in conjunction with software such.
The bahtinov mask achieves perfect focus in seconds. Although masks have long been used as focusing aids, the distinctive pattern was invented by russian amateur astrophotographer pavel bahtinov russian. The bahtinov mask the sky at night in digital images. Farpoint fp410 bahtinov focus mask celestron 8in sct fp410. Bahtinov grabber for any camera niels noordhoeks weblog. There might have been condensation on the lens but i do not know. To 3d print the bahtinov mask as shown in the images above, i used opencad a free software and a readymade tweakable template or model called bahtinov mask generator modded which i found on. The bahtinov mask has become the preferred method of focusing a telescope, either visually or when imaging with a ccd camera, dslr or webcam. Farpoint manufactures this lifesaving astrophotography tool out of virtually indestructable abs plastic and comes in two major types and in a range of sizes. Bahtinov masks present an ingenious new way to easily focus your webcam, dslr, or ccd camera for astrophotography. The bahtinov mask gets focus as good as can be achieved with this lens.
I have used the bahtinov mask feature and byes fwhm. Lightweight, precision cnc cut, non flexing and with adjustable rubber tabs. This model generator allowed for the size of the mask to be adjusted according to the measurements of my own telescope. 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. Starwave tm bahtinov masks are adjustable to fit a wide range of optical tubes, unlike. This customizable design generates custom bahtinov masks, which are used to aid focusing telescopes during astrophotography.
Precise focusing of telescopes and astrographs is critical to performing astrophotography. 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. They are an inexpensive tool which will allow you to achieve pinsharp levels of focus, saving you time and improving your work. It is very easy to use and will result in obtaining precise focus with a camera lens. I have made a new mask the carey mask, which i think can be even more accurate than the bahtinov. 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. I have recently purchased a sigma 1424 art to use primarily in widefield astro.
This indispensable astrophotography tool is constructed from nearly indestructible abs plastic. Fine focus and bahtinov masks ask craig stark labs. The spikea attaches securely to your scope using nylon screws to ensure the finish of your telescope is protected. Im running the 32bit version on a netbook, canon 300d camera and dslrfocus software. Jan 02, 2014 to help get an accurate focus with my c11, a bahtinov mask was placed over the corrector lens. Farpoint bahtinov mask for refractors or newtonians with 5. When precize focus is achieved the pattern becomes symmetrical. Basic and advanced tips for getting the most out of this popular. Achieving focus has been a tough challenge since i began with astrophotography, so i decided to do something serious about it, preferably something that does not cost a lot of money. Apt has a function called bahtinov aid based on bahtinov grabber technology and it provides an excellent visual and digital reference when using a bahtinov mask to come to focus. Its also much quicker than focussing using software. In each panel, im showing the star as viewed with top and without bottom the mask in place. Telescope focus aids telescope focus masks high point. Here, ill show a video of me using both the current version of the fine focus tool and augmenting this with the use of a bahtinov mask.
The bahtinov mask is a device used to focus small astronomical telescopes accurately. Farpoint bahtinov mask telescope focusing aids bintel. Farpoint astro bahtinov focus mask for meade 10 sct fp4. We have not yet decided if we are going to do this. Bahtinov mask created by 3d printing astronomy notebook. Thus, my idea of a tri bahtinov mask that has three bahtinov masks arranged in a 3fold symmetric fashion. This farpoint bahtinov mask fits telescopes with outside diameters of between 5. With adapter it fits lenses smaller than 77mm outer diameter.
These are not generic masks, each mask is tuned to the telescopes focal ratio for the very best performance. If you get a deadon polar alignment, and focus then on a near by bright star, using the fwhm feature is really superior to the bahtinov mask. Input values appropriate for your telescope, and press the generate. For focusing the image of a telescope, one can use a bahtinov mask. Had access to 3d printer, so i made a bahtinov mask. Some friends of mine recently won a 3d printer in a contest, so i thought id design and print a bahtinov mask for my telescope. This symmetry should produce a diffraction pattern that is also. Bahtinov mask other focusing methods astronomy notebook. Two of them form an x shape, and another spike crosses it, forming a shape. I can also say without reservation that the spikea mask is the bestmade version ive seen.
How does this mask work, and how did mr bahtinov get the idea to cut such a peculiar shape. Use of this network, its equipment, and resources is monitored at all times and requires explicit permission from the network administrator and focus student. Improve your astrophotography focus with a bahtinov mask. Bahtinov focus mask to fit canon efs 1585mm adapter to fit canon ef 100mm f2. Comparison of focusing masks gabor toth astrophotography. A bahtinov mask is a focusing aid for astronomy in general, and. Bahtinov focus masks are the brainchild of pavel bahtinov, a russian amateur telescope maker and astronomer. Shop great deals on millions of quality used products browse now. This example shows a simulation using another of niels software marvels maskulator. Since there was a very bright star in the field alnitak, the leftmost star in orions belt, the diffraction pattern produced by the mask was easy to see in the camera display.
Whilst its of no use to me now, before i used autofocus the bahtinov grabber was so useful to quickly achieve accurate focus so i think it would be a really useful addition to sgp. Farpoint bahtinov focus mask for celestron 8 classic sct. The bahtinov mask is a very elegant solution to one of the biggest problems that besets the deep sky astrophotographer focus. Although masks have long been used as focusing aids, the distinctive. 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. On a recent shoot i used mf set to infinity but focus was off. Farpoint fp410 bahtinov focus mask celestron 8in sct. It consists of a disk made of opaque material fitted over the telescope objective with slots cut out in a specific pattern devised by amateur astrophotographer pavel bahtinov. The mask is a joy to use, and makes absolutely precise focussing easy and quick, and is more accurate than the traditional hartmann mask. Sep 07, 2016 the mask will produce six long angled diffraction spikes on the star. Bahtinov mask other focusing methods the bahtinov mask, invented in 2005 by a russian amateur astronomer, pavel bahtinov in 2005, is a device used to focus using a bright star. Pick on a nice high contrast region the moon has lots and it is quite simple and gives good results. Using and making flyscreen bahtinov mask for focusing. I used the patterns from astrojargon and copied the rest from my telescopes normal cap im super impressed with how well it works, and gets the focus way more accurately than i could by eye.
The bahtinov mask makes it easy to focus your dslr camera, ccd camera, or webcam when imaging the night sky. The other mask is designed to fit schmidt cassegrain telescopes. How to make bahtinov mask, pdf templates deepsky watch. 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. After reading many discussions and articles in web pages and forums i decided to build my own bahtinov mask. It will require a dslr to be unmounted to attach the mask and again to remove it, but that is a minor issue. Great bahtinov mask for c11 with hyperstar or without. As long as the mask slots are not damaged, the mask should continue to perform well over time. I have down loaded the software, and a box with set capture area, and donate is all that shows up. Bahtinov mask the easiest way to achieve sharp focus. 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.
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