karen_liles Posted July 29, 2003 Share Posted July 29, 2003 I recently received this information about Mars and wanted to see if anyone could give me suggestions for getting a proper exposure. I didn't know what forum to put it under so if "Nature" is not the right one, please let me know. Thanks for any advice! (P.S. I don't have a telescope. I have a 150 mm lens on my medium format camera, and a 200 mm lens on my 35 mm camera.) Never again in your lifetime will the Red Planet be so spectacular. This month and next Earth is catching up with Mars, an encounter that will culminate in the closest approach between the two planets in recorded history. The next time Mars may come this close is in 2287. Due to the way Jupiter's gravity tugs on Mars and perturbs its orbit, astronomers can only be certain that Mars has not come this close to Earth in the last 5,000 years but it may be as long as 60,000 years. The encounter will culminate on Tuesday, August 27th when Mars comes to within 34,649,589 miles and will be (next to the moon) the brightest object in the night sky. It will attain a magnitude of -2.9 and will appear 25.11 arc seconds wide. At a modest 75-power magnification Mars will look as large as the full moon to he naked eye. Mars will be easy to spot. At the beginning of August Mars will rise in the east at 10 p.m. and reach its azimuth at about 3 a.m. But by the end of August when the two planets are closest, Mars will rise at nightfall and reach its highest point in the sky at 12:30 a.m. That's pretty convenient when it comes to seeing something that no human has seen in recorded history. So, mark your calendar at the beginning of August to see Mars grow progressively brighter and brighter throughout the month. Share with your children and grandchildren. No one alive today will ever see this again! Link to comment Share on other sites More sharing options...
brady_dillsworth Posted July 29, 2003 Share Posted July 29, 2003 http://www.space.com/scienceastronomy/mars_orbit_030121-1.html This site seems to correct some of your misinformation. But in general you seem to be correct. Link to comment Share on other sites More sharing options...
phule Posted July 29, 2003 Share Posted July 29, 2003 Personally, I'd like to rent a telescope for the event, with or without a camera attached. Link to comment Share on other sites More sharing options...
art_haykin Posted July 29, 2003 Share Posted July 29, 2003 I would consult books and sites on Astrophotography. You'll not get much with most any regular camera lens. You'll need a telescope with a tracking motor to do it right. Link to comment Share on other sites More sharing options...
frank uhlig Posted July 29, 2003 Share Posted July 29, 2003 Karen, please do not get fooled. This is an astronomical event: 75 fold mag will give Mars the appearance of a moon sized object, you say. In 35mm, this magnification would require a 75 x 50 mm = 3750 mm 0r 3.75m or about 4 yards, or about 12 feet long lens. Just to appear as the moon would with a 50 mm lens, i.e., almost not there at all on film. You may experience this proximity of Mars in person by enjoying a slightly brighter look at Mars, but to record it for posterity is - unfortunately - not for those without a huge telescope, nor for us with 200mm, or even 600 mm lenses. Are you in accord? A photographic non-event by all means of reason ... Link to comment Share on other sites More sharing options...
bobatkins Posted July 29, 2003 Share Posted July 29, 2003 It will be relatively easy to get a shot of Mars, but it will just look like a red star on film. Not very spectacular, but if you want to do it just use fast film, use your lens at it's widest aperture, point it at Mars and give it a few seconds exposure. You'll get Mars and some of the brighter stars. It's also not going to be THAT much closer than usual! Link to comment Share on other sites More sharing options...
bert_krages1 Posted July 29, 2003 Share Posted July 29, 2003 Using the lenses you describe, Mars will record as bright and distinctive dot on an image. Probably the best way to photograph it with conventional equipment would be to incorporate it into a landscape image. To reduce trailing caused by the Earth's rotation, you will want to keep the exposure down to a few a seconds (e.g., ten seconds with a 50mm lens on a 35mm camera body, three seconds for a 200mm lens). You will need a telescope with a substantial motorized drive to get an image large enough to record planetary detail. At the level needed for astrophotography, the telescopes and mounts are both expensive and bulky. They also require a fair amount of experience to use proficiently. Link to comment Share on other sites More sharing options...
stephen_ratzlaff Posted July 29, 2003 Share Posted July 29, 2003 If you have a small digital camera you can try to photograph Mars via eyepiece projection and get pretty decent results if you make an inexpensive mount for your digi-cam. Go here for more info on Astrophotography and other info on telescopes. http://www.weasner.com/etx/menu.html Mike's site is geared a bit for the Meade ETX products, but there is also a wealth of info regarding astronomy in general and the info provided can pertain to any brand of telescope. As I have a Meade ETX-90RA scope (inexpensive) this is the site I found most useful, but I'm sure there are a plethora of sites with astrophotography info out there. There are also a lot of tips on how to make gear. Regards Link to comment Share on other sites More sharing options...
gauthier Posted July 29, 2003 Share Posted July 29, 2003 I watched Mars myself for the last several days and I can confirm that I've rarely seen the red planet so red and so bright. On the other hand, even with 8x50 goggles, it's barely more than a point in the sky, and that is already the rough equivalent of a 400 mm lens. A star trail including Mars could be spectacular and easy to record, but any meaningful attempt to capture the planet on film or sensor will need to involve a telescope with a SLR attachment. You'll need at least a 6 inche telescope (10 inches would be even better) with an engine that keep the telescope pointed on Mars. In short, you'll need to associate with an amateur astronomer and to do a lot of reading on astrophotography and such. Fortunately, the info is readily available on the web. Link to comment Share on other sites More sharing options...
alex_lofquist Posted July 29, 2003 Share Posted July 29, 2003 I intend to photograph it within the next few weeks with a 500mm f/4 and a 1.4X TC. If I have calculated correctly, Mars should have an image diameter of about 1/12 mm, which would be barely resolvable as a disk. I expect that exposure times with ISO 400 will be about 1/10 sec, or less, to avoid trailing. I'll bracket a lot just to get something on film. At least I can say that I tried! Link to comment Share on other sites More sharing options...
greg s Posted July 29, 2003 Share Posted July 29, 2003 Good thread! At a minimum I will keep a closer lookout on the Aug sky. Plus, I'll put my longest reaching gear together and take a photo of a red dot = fun no matter what. :) Who knows, perhaps I can pickup some very faint detail. Link to comment Share on other sites More sharing options...
karl_lehmann Posted July 29, 2003 Share Posted July 29, 2003 Actually Mars is already A LOT brighter than usual. It only gets reasonably bright about once every two years, and very bright about once every four years.<P>With your equipment the best way to record it will be to include it as part of a dusk or dawn landscape (it will be opposite the sun at its brightest, so shoot away from the sunset or sunrise). Just shoot normally for a twilight landscape a half hour or so after sunset or before sunrise and Mars will appear as a very bright red-orange star.<P>Start with a landscape that would stand on its own without Mars in the sky (in other words don't try to make Mars the main subject unless you've got a telescope).<P>For a star chart (to find out when Mars will be where you want it) go to http://skyandtelescope.com and click on "Sky Chart".<p>Karl Lehmann <a href="http://www.lostworldarts.com/new_page_3.htm">Lost World Arts</a> Link to comment Share on other sites More sharing options...
awahlster Posted July 29, 2003 Share Posted July 29, 2003 Well guys I think I can help out here. A week ago I set up my 500mm f4.5L Canon with a Vivitar 4X eye pc. adapter making approx. a 40X telelscope and with NO problem at all the wife and I were looking at the planet Mars it appeared to our eyes as if it were approx. 1/8" in diameter. with the addition of my 2X-A it was quite easy to see a clear picture of a planet. SO with a decent 400 asa film and a 16X20 size enlargement of my negitive I'll have a very very decent size photo of Mars. The astrophotogarphy sites are talking about being able to see the white for the polar ice caps with high power binoculars (my guess is this maens 20X) My new Meade ETX-90 telelscope with all the godies for both film and digital photogarphy will be here on August 5th. As soo as I can get an image I'll post it for all to see. and remember it is getting closer and will be retreating for some time so if you don't make a good viewing on the best night one close by will look pretty good. Link to comment Share on other sites More sharing options...
karen_liles1 Posted July 29, 2003 Share Posted July 29, 2003 This is fantastic! Thanks so much for all your answers. I especially like the link Karl posted (skyandtelescope.com). I'll be anxious to see the pictures taken with telescopes. I'm still going to try to photograph it, and even if I don't get a decent picture, I'm sure it will be fun. I might have to explain it to others, but at least I'll know what it is! Link to comment Share on other sites More sharing options...
bobatkins Posted July 30, 2003 Share Posted July 30, 2003 I would not underestimate the difficulty of getting a decent photograph of Mars. Here's an example using a 4" f5 fluorite refractor telescope at 70x, eyepiece projection though a 50mm lens, EOS 10D at ISO 3200, shutter speed 1/60. I think this is about as well as you will do without special astrophotography accessories and a larger telescope. Yeh, may be you can tell it's Mars. In fact you can see the polar cap quite clearly. If I wanted a real picture though, I'd download one from the Hubble website...<div></div> Link to comment Share on other sites More sharing options...
bobatkins Posted July 30, 2003 Share Posted July 30, 2003 This is what it really looks like...<div></div> Link to comment Share on other sites More sharing options...
Glenn McCreery Posted July 30, 2003 Share Posted July 30, 2003 Other photos of mars and other subjects are available from the NASA Astronomy Picture of the day web site: http://antwrp.gsfc.nasa.gov/apod/astropix.html Once in a while an amateur photographer or astronomer is featured. I tend to start my day at work by checking this web site and then photo.net (that is, before actually starting to work). Link to comment Share on other sites More sharing options...
neal_vaughan Posted August 21, 2003 Share Posted August 21, 2003 "In 35mm, this magnification would require a 75 x 50 mm = 3750 mm 0r 3.75m or about 4 yards, or about 12 feet long lens. Just to appear as the moon would with a 50 mm lens, i.e., almost not there at all on film." That makes absolutely no sense at all. Link to comment Share on other sites More sharing options...
karl_lehmann Posted August 21, 2003 Share Posted August 21, 2003 Here are some good amateur shots of Mars, taken by Ed Grafton two years ago. He used a 14 inch reflector, but Mars is much closer now.<P> <a href="http://skyandtelescope.com/mm_images/4966.jpg">http://skyandtelescope.com/mm_images/4966.jpg</a> <P>Note: images © Ed Grafton <p>Karl Lehmann <a href="http://www.lostworldarts.com/new_page_3.htm">Lost World Arts</a> Link to comment Share on other sites More sharing options...
lance_free Posted October 30, 2003 Share Posted October 30, 2003 Although the event has past, for the sake of posterity, I would like to substantiate Frank Uhlig's thumbnail sketch with my experience: ======================================= "In 35mm, this magnification would require a 75 x 50 mm = 3750 mm 0r 3.75m or about 4 yards, or about 12 feet long lens. Just to appear as the moon would with a 50 mm lens, i.e., almost not there at all on film." ===================================== A lens with a 12" (300mm) diameter aperture and a focal ratio of 10 has a focal length of 3000mm. Using eyepiece projecion techniques with an eyepiece of 10mm (3000mm/10mm = 300x magnification), the focal ratio now becomes 50 and the effective focal length is (300mm aperture x 50 =) 15000mm. That's fifteen thousand millimeters. At that focal length/magnification, Mars at it's nearest point relative to Earth for quite some time STILL does not fill one 35 mm frame... not even close: I'd estimate about 1/6th, perhaps less. Mr. Uhlig is correct, at 75 times magnification or 3750 mm focal length, Mars appeared no larger than the moon with a "normal" lens. In fact, I'd suggest quite like a lot smaller in terms of perspective (remembering our perspective is nearly 180 degrees), although in terms of magnification, perhaps not too far off. Further, Karen Liles' "modest 75-power magnification" making Mars look like "the full moon to (t)he naked eye" comment isn't far off if you consider how small the moon appears relative to our nearly 180 degree "normal" field of view. To illustrate my point, viewing viewing Mars at 75x magnification is akin to viewing a full moon with a 14mm diagonal fisheye lens. If anyone is interested in astrophotography, there are some tremendous books on the subject and numerous websites with astrophotographers' work on display. One of the most comprehensive sources of information is, in my opinion, 'The Backyard Astronomer's Guide' by Terence Dickinson and Alan Dyer. It offers a thorough overview of equipment used for viewing and photographing a wide range of astronomical objects and, although recently updated, it has been considered 'standard' reference material for beginning enthusiasts for nearly a decade. Here's to looking up! ~LF Stamp out light pollution! Link to comment Share on other sites More sharing options...
michael_matassa Posted April 27, 2004 Share Posted April 27, 2004 Here's a picture of Mars I took last September with a 10" SCT and a 2.5x barlow (making for f/25) and a Starlight Xpress ccd camera. Combination of 3 exposures using red, green & blue filters.<div></div> Link to comment Share on other sites More sharing options...
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