How To Build A Meteor Capture Camera

Leonid 2012 by Mike Hankey

Nothing tin replace the thrill or experience of witnessing a vivid meteor, falling star outburst or fireball with your ain ii eyes while wrapped in a sleeping bag on a common cold winter forenoon. These visual thrills are the benefits of shooting star observing, and while that 1 fireball experience will brand up for ten frostbitten toes, nosotros cannot e'er afford the costs associated with visual observing which include time, missed sleep and sometimes physical suffering. Is it worth information technology to stay upwards all night in the freezing cold to see some flashes of calorie-free cross the sky? Of class it is. Is there an easier way to observe a meteor shower that requires less of an investment in time and energy? Yes at that place is.

With the advent of digital photography, taking pictures of meteors has become much easier and cheaper, and as a result, a new observing method and art class is taking shape. Digital meteor photography can supplement or replace visual or video observing sessions. The benefit of camera observing is unproblematic — when yous stop your session, hopefully you will have one or more shooting star pictures that you can study and share. The picture will not only be a slice of scientific discipline, but a slice of art.

I can certainly debate the pros and cons regarding the different meteor observing methods — which is nearly effective, accurate, fun or scientifically valuable. I believe the all-time observing method is tethered to the goals of the observer. If you are but concerned with hourly rates, then radio observing is probably the best approach. For those who want the experience, nothing can top visual observing. Falling star scientists tend to favor all heaven camera video and believe the ideal exposure time for a shooting star is a fraction of a 2nd. While it's true a DSLR tin miss low magnitude meteors, and it will not exist able to guess the shooting star velocity (without modification), the DSLR will tape the meteor location relative to other stars with a degree of precision much higher than an all heaven camera.

People have been taking pictures of meteors for decades, merely with the onset of digital cameras this task is at present much easier and cheaper than ever before. Equally a spoiled astronomer raised in the electronic age, I tin can't fathom how someone could accept coped with moving picture based astrophotography twenty or more than years ago. The immediate feedback organisation of a digital camera and its ability to take hundreds or even thousands of pictures in a unmarried night are disquisitional to success with shooting star photography. Nosotros never know the exact moment when a meteor will shoot across the sky, so, if we desire to catch i on camera, we must photograph the sky all night long.

The cost of capable DSLR cameras, lenses and accessories has come down in contempo years, and yous tin acquire all of the basic equipment needed for falling star photography for around $1000. Of grade those with a gustation for the high finish could spend twice that on just a lens, but for the sake of this article nosotros volition continue it simple.

To take good photographs of a falling star shower, at a minimum you lot will need the following equipment:

• DSLR Camera
• Fast, wide bending camera lens
• Intervalometer
• Tripod
• Large chapters retention card (xvi gigs or improve)
• Extra Batteries, AC power supply, or DC power adapter & large battery
• Dew heater
• Pocket-sized hand towel

A review or recommendation of cameras is out of scope for this article, but for photographing shooting star showers, the important things to have on your camera are: 1) a transmission fashion setting where the exposure fourth dimension, ISO and f-ratio tin can be fix and 2) a port to plug in an Intervalometer. If your photographic camera has these 2 things and can exist mounted on a tripod, then y'all tin can use information technology for falling star photography.

Mike Hankey with Perseid Meteor at Picket Dome, Yosemite National Park – August 12th, 2012

The camera lens is the single most important investment you can brand in your meteor photography rig. There are ii things about the lens that are most of import — the f/ratio and the field of view (FOV). We will start with the FOV because it'due south simple: the wider the field of view, the more heaven you tin capture and the more meteors you will catch per hour. Unfortunately, as you go wider you lose resolution considering more heaven is existence placed into the same number of pixels, in effect making each object smaller. While many of u.s. desire to paradigm the unabridged heaven, frequently a meliorate quality picture can be taken with a smaller field of view.

The f/ratio or lens speed is unremarkably written on the lens as a ratio (for instance, f/two.8), and represents the focal length divided past the discontinuity. The f/ratio tin can exist a difficult concept for new photographers, but what it ways in meteor photography is this: with a faster lens y'all will capture fainter meteors. If the f/ratio is also loftier, you will miss virtually meteors. Ideally you want something in the < f/ii.0 range. I have been successful with lenses up to f/2.8, but in my experience, once you lot become above f/3.0, your prospects of catching meteors rapidly diminish. There is nothing more frustrating than watching a falling star wing through your field of view only to check the camera and discover out that the meteor was not imaged!

An intervalometer, also called a cable release, is a device that allows you to program and control the photographic camera shutter without touching the photographic camera. These devices tin be programmed to take pictures in intervals using the camera's 'seedling' setting and are often used for time lapse photography. There is too a button that, when locked in place, is equivalent to continuous shooting. The cable release controls your camera so yous do not have to.

Power management and data storage are also considerations when photographing meteors. If you want to go all night long, a large capacity memory carte and a few back upwardly batteries are needed. A continuous or long term ability supply is not required but nice to have, since virtually batteries will only give y'all about 2 hours of continuous shooting. There are two useful camera power adapters fabricated for nigh cameras. Both mimic a battery and are inserted into the camera in the same way. A wire hangs out of the battery port and will plug into either an AC wall outlet or a DC car lighter way outlet, depending on which adapter you have. If you lot're close to home, you tin employ the AC adapter and an extension cord to power your camera all nighttime long. The DC adapter is normally used with car-battery-type power supplies. Using this power adapter with a Celestron Power Tank, for example, volition give your photographic camera and dew heater enough juice for the entire night. I often use the Air-conditioning adapter from my yard only rely on the DC adapter and power tank when shooting from a remote location.

If you lot desire to photo meteors all nighttime long, you will need to exist able to proceed condensation off of your lens. Dew in the summer and frost in the winter can fog out your lens within the first hr of shooting. The most constructive tool for preventing this is an astronomy dew heater designed for use with a telescope. An Internet search for 'dew heater' will reveal numerous tools that can exercise the job. Virtually are just a Velcro strap that you wrap around the camera lens. A wire run through the strap is heated by electricity and this keeps the lens warm plenty to prevent condensation. Most dew heaters are powered by a DC ability source, so a DC ability camera adapter and the Celestron Ability Tank compliment the dew heater nicely. Your camera and these three accessories (dew heater, DC adapter and tank battery) make a powerful astrophotography bundle that you tin easily take anywhere.

Focusing is one of the most important steps, and your images should always exist reviewed on a big computer screen before committing an unabridged night to the current settings. In general, to image the night's sky, you must plough off auto focus and move the lens focus to the infinity position. This is often the last cease on the focus knob, but on some lenses perfect focus tin can be merely short of this or just afterwards it. I recommend using an A/B examination process and the LCD lens at full zoom. For example, set the photographic camera focus to infinity and have the outset picture. At present bring the camera focus one step closer or further away from the infinity position and take the second picture. Find a star in the flick and zoom in as much every bit possible on that star. Switch back and forth between the two pictures to see which focus is better. Change focus directions when the focus starts to dethrone. Do this higher up and below the infinity position until y'all find the perfect focus position for your lens. Finally, review the photo in your computer and make sure information technology looks skillful before shooting all night with this focus position.

When yous are starting out with anything new, it's important to experiment, test different methods and fine tune your procedures to find out what works best for your equipment and your nighttime sky. I am still tweaking different aspects of my methods, settings and equipment and improving on the effectiveness and quality of my falling star photography. Even so, at that place is a core part of the process that remains constant every night. Keeping it simple and having a documented routine profoundly increases the chances of not making a dumb error and ruining a night's worth of opportunity.

Meteor with Jupiter and Venus – March 14th, 2012 by Mike Hankey

Here is the procedure that I follow when setting up and executing a shooting star photography run.

1. Take a charged Celestron Power Tank handy.
2. Cheque the weather and make rain plans if needed
3. Check memory menu for bachelor storage; articulate off if needed
4. Verify time on camera is right
5. Verify file save settings are medium JPG and RAW
6. Install DC power adapter into photographic camera and plug into power tank
7. Put memory menu into camera
8. Wrap dew heater around lens without blocking or touching focus knob (if possible)
9. Mount photographic camera on tripod
10. As one unit move the tripod, photographic camera and battery to the shooting location
11. Set camera settings for ISO to 400-800 depending on conditions
12. Prepare f/ratio to lowest possible setting because light pollution
13. Set camera exposure time considering light pollution, usually betwixt 10-25 seconds.
14. Frame the shot
15. Focus the camera using focus procedure
16. Review film focus quality on camera LCD
17. Tweak shot, photographic camera settings and focus until adequate
18. Review motion picture focus and settings quality on computer for terminal time
19. Outset shooting by locking the cablevision release push button in place
20. Wrap camera with hand towel to preclude dew from getting on camera
21. Bank check in within first hour of shooting and a few times through the night.
22. Set warning to remember camera at dawn and so go to bed.

If everything is working right, and y'all are located in a safe, crime complimentary area, you lot can go to bed after the first check in, and the camera should operate all night long. Things that can potentially get wrong and ruin your imaging session include: filling upwards your memory carte early on, running out of power, having your lens fog upwardly or frost over, shooting out of focus, or taking pictures with the wrong combination of ISO, f/ratio and exposure time. Documenting and following the same procedure every time will help guarantee success on nigh of your image runs. It could rain, or your photographic camera could be stolen or knocked over past the current of air, so program accordingly. Yous should also make plans to retrieve the camera at dawn, as taking long exposures of sunlight puts unnecessary strain on your camera's CCD chip.

In the morning you will have a potential treasure trove of meteor photos waiting for you. Finding a few meteor gems in an ocean of 500 or more pictures tin can exist time consuming if you lot don't have a proficient review process. Of disquisitional importance to the review procedure is having a low res version of the pictures so you can speedily scan through them on your computer. I recommend saving the images in two formats; RAW will preserve the image in the highest quality possible, and a medium or low resolution JPEG will let you lot to preview the image without having to expect for your reckoner to load and return it (something that can take a few seconds with high res images).

When I review the images I open up only the JPGs in an prototype viewing program. I and so press the cursor central to accelerate the image and I keep it pressed in. This creates a movie type of outcome with a frame rate of well-nigh i-2 frames per second. I then quickly scan the entire paradigm looking for irregular differences or flashes and terminate when I see them. I take to weed out plane and satellite trails just somewhen am left with a few good falling star photos. Each time I discover a photo containing a falling star I rename the file by adding the prefix 'meteor' to the file name. This will proceed the motion picture out of the batch the adjacent time I do my review. I will usually do this review at least two or three times and sometimes more depending on the field of view. During some showers, like the Geminids, when using a wide angle fisheye lens, I may review the lot five or more times and continue to detect meteor photos after each pass.

Once I'm confident I have found and renamed all of the meteor photos, I create a directory on the memory card named after the appointment and shower name and movement the meteor photos into that directory. I volition and so delete the rest of the photos on the memory card and free up the space past emptying the trash or recycle bin. Keeping an entire night's worth of high res photos takes upwardly lots of gigs of infinite and is a waste of time and resources to re-create to your hard drive. That's why I perform the review and file separation on the card the mean solar day afterwards the imaging session. I then only copy over the meteor photos to my calculator, instead of the entire night's images.

Now that y'all accept some squeamish single image meteor photos, what practice you do with them? For starters, If y'all have an AMS account or utilize Facebook become to  the AMSMeteors.org website under the menu Photos & Videos /Photos you will detect an "Upload a Photo" button and share your photos there.  In addition there are numerous outlets where yous can publish your falling star pictures, including: The Meteor Observers Mailing Listing, Space.com, Facebook, Cloudy Nights and other astronomy websites. During a meteor shower at that place is usually a lot of interest from the media and local news websites, and blogs will often gladly publish your shooting star photos. I have even seen some shooting star photos go published on national news websites.

From a plotting perspective, a DSLR volition tape a falling star location with a level of precision much higher than some other recording devices such as a single fish-heart all-sky camera or unmarried radiometer.  This is because thousands of stars are captured in a long DSLR exposure with a fast lens compared to the dozen or so stars defenseless by a video photographic camera with a slower lens. The larger paradigm size and higher resolution picture too makes precise plotting much more reliable. While an all-sky fish-eye video photographic camera will gather more than scientific data, specially the falling star velocity and light curve, the lack of resolution and star detail in an all-sky arrangement are shortcomings. For these reasons, I believe the perfect all heaven solution would use both a fish-eye video camera and a DSLR with a fast total heaven lens attached. This combination would allow the top and azimuth angles associated with a fireball to be determined with a much greater level of accuracy. A DSLR could also be used with a multi-camera all- sky array as a special radiant direction monitor during showers.

In the previous descriptions, information technology has been assumed that a whole series of unmarried "time-lapse" exposures were made and individually saved such that information technology was always articulate that the camera settings including ASA, f-ratio, exposure time and clock timings would exist identical for a whole night's run of images. Every bit such, subsequent scientific use of the images and rigorous information reduction procedures are quite well-known and applicable without resorting to elaborate proprietary schemes.

I such method consists of "stacking" the private images obtained sequentially by a stationary (relative to the ground). In such stacks, particularly when only frames that have a visible meteor on each are superposed, the stars (and/or planets) will not be trailed but rather appear as a serial of dots. It is relative easy figuring which stars go with which meteors and then that both meteor effulgence and sky relative begin and cease points may exist determined. Such edited stacks are a grade of paradigm processing that is particularly valuable during meteor showers, only in general they must be reduced by manus. Only when a rare "stationary" shooting star occurs can a radiant exist adamant from 1 meteor. Otherwise information technology takes finding the convergent betoken using all the shower meteor trails recorded to get a radiant position. Meteors that miss the radiant area past 10s of degrees are sporadic meteors.

Even if you can't determine magnitudes and positions rigorously, scientifically yous can determine the meteor frequency as adamant by your camera and tally the meteor counts in the same mode you lot would in a visual session. While these counts may be less than those of visual observers (considering the faintest meteors aren't always defenseless), a frequency count of DSLR meteors would be interesting to runway over the course of a meteor shower or from year to year equally a special project. Hither is an case of such a stack that is useful besides as ornamental provided full technical details are given. If the stack is made by superposing all of the images whether or non they contain a falling star and so such data are conveniently indicated in the class 24x300s from which a full exposure of 2 hours tin exist calculated. Otherwise the total bridge of the exposure equally indicated as the start (outset meteor image) and end times (last shooting star image) should be given.

Composite Image of Perseid Meteor Shower – August 12th, 2012

One would think that DSLRs should take evolved into the perfect meteor system. Over the last decade, however, DSLR camera designs accept been extensively modified in response to the demands of professional photographers whose merchandise increasingly requires drastic "retouching" of originals to satisfy client preferences and demands. Included these days are features that can automatically change a camera scene in such a way that the original information that may be of scientific (every bit opposed to artistic) value, can never be recovered. But fifty-fifty if your camera does not provide such on camera processing, dozens of "photoshop" clones are now bachelor that will allow performing hundreds of artistic transformations (normally without a "paper trail") to whatever image regardless of source. Such drastic "retouching" is called Loftier Dynamic Range (HDR) epitome processing and as information technology can likewise be performed after taking a series of celestial exposures, HDR modified sky scenes accept appeared without adequate documentation on the internet and fifty-fifty in recent popular astronomy magazines.

HDR is blazon of "image compression" but because it is always non-linear it means that there is no guarantee it is reversible without loss of information. This is fabricated worse if original HDR files are converted to other formats for transmission over the internet. Other known types of lossy compression whether or non they contain HDR modified images include JPEG and GIF. ( https://en.wikipedia.org/wiki/Image_file_formats ) Most HDR "originals" are recorded in the cameras as "raw" format.  Common prototype file formats that tin can include original HDR images (xvi or 32 bit) from which the "original" image information "might" be extractable will accept "HDR" attached to the suffix. ( https://en.wikipedia.org/wiki/High_dynamic_range_imaging)   If there is no HDR notation fastened, it must be assumed that the file has been converted in a non-recoverable way.

So if you are submitting HDR or fifty-fifty custom "stacked" exposures to the AMS or other scientific organizations you should exist honest and disclose such processing details when your epitome is submitted. At that place are scientific instances when such images are appropriately used with little notice of processing methodology, i.e. NASA spacecraft images where the applied image processing has been standardized with widely publicized details and software distributions that are publicly bachelor and for which total details do not have to be repeated for each image. If the image submission process does non allow posting of sufficient processing details with your images and so send an e-mail to the listed person responsible for the use of your prototype. Your thoughtfulness will be truly appreciated.

Source: https://amsmeteors.org/meteor-showers/how-to-photograph-meteors-with-a-dslr/

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