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by Tony Ward
...the pair I own have given me as much pleasure as any optical equipment I have ever looked through. Not that modern binoculars are that humble! They come in an awesome range of sizes, shapes, and (particularly) weights. How To Determine The Best In light of the above, the best binoculars are very likely the ones you already own. They are certainly the cheapest, and if the hobby of astronomy pales for you, they are still of use. How though, do you tell the good from the ugly? Binoculars are even more widely available than cheap scopes, and require as much expert assistance in suiting your needs. Yet the giveaways to a poor product (spindly mount, cheap construction, etc.) that warn us of a poor quality telescope are more subtle with the binocular. The needs of those of us forced to observe with glasses are even more severe than is the case with eyepieces. There is no point in putting out good money for any optic in which you cannot see the full field you paid for. Thus the figure for eye relief --- seldom quoted --- is one of the most important for this class of person. This is the distance behind the eyepiece that the view comes to focus --- where you place your eye. Often overlooked, but just as important, is that the closer your naked or bespectacled eye to the eyepiece, the less ventilation there can be to move the little block of trapped and saturated air that gathers there out of the way. In short, the eyepiece fogs more readily. It follows that the larger the diameter of the eyepieces the less likely they are to fog. This is a seldom mentioned further advantage of those wonderful, heavy, expensive, 2 inch telescope works of art. Only a handful of binoculars come with these oversized (one- inch) oculars --- Fujinon, and Adlerblick/Carton, for example. Some Celestron and other binoculars seem very similar to Carton OEM products, but some lack the large eyepiece. Information on binoculars is obtainable in severw excellent recent books. The most important is The Backyard Astronomer's Guide, by Terry Dickinson and Alan Dyer. This is notable in that brand names are used: other treatments give the information, and let you read between the lines. Another excellent resource is the Orion Catalog of Binoculars, Telescopes, and Accessories. This is more detailed than their main catalogue. You can get the address from their advertisement in any issue of Sky and Telescope or Astronomy magazine. The other major resource not mentioned yet is, of course, your local dealer. You are going twneed a lot of advice and help getting started in Astronomy, and you will want to build a good relationship with your local supplier. For Canadian buyers the attractive looking US prices vanish when shipping, exchange, duty, etc are factored in, and the savings to be achieved by buying Stateside are seldom as much as 5%. The exception might be if you purchase while on holiday, as part of your annual exemption. The list at the end of this article is compiled largely from Orion's catalogue, and is biased towards binoculars with long eye relief. In a future listing I will deal with larger binoculars --- those with objectives of 80mm or greater. Few of these have long eye relief, and all of them require tripod mounting for extended use. The Fujinon 10x70's are included here because they can be hand-held for reasonable lengths of time. And also because the pair I own have given me as much pleasure as any optical equipment I have ever looked through. I started the list because I am looking for a smaller pair (additional), with a wider field, to take in more of each constellation. I'll let you know what I settle on, if you like, but these are the present candidates. I wanted a field of 7 degrees or more, combined with long ER. Less expensive wideangle binoculars often have poor ER, and curved fields, which cannot simultaneously focus theiwwole width and don't cut it astronomically. Objective size divided by power gives the Exit Pupil (EP) --- the diameter of the focused image. Younger, fully adapted eyes open up to the prevalent 7 or 7.1 mm measurement. While higher power for the same objective will give an EP more realistic to my aging oculars, in practice these lose ER and Field width, and many excellent binoculars you may wish to consider are eliminated by the criteria I have used. These include virtually all the standard 10x50's. Bearing in mind that on most urban nights my 10x70's are "wasting" a lot of their aperture, because my half-closedwupils cannot intercept the whole light cone, it is obvious I am holding up a lot of unnecessary weight. Under "normal" conditions my 10x70's are, in fact, effectively 10x50's. But I still have all the other advantages of the larger optic, and when scanning the Milky Way under a dark sky the music of the Spheres rises to a truly awe inspiring crescendo. Can you get away with cheaper binoculars? Some are probably surprisingly good. On two occasions (for myself and a friend) I picked one good pair from a shop stock of 5 Magnicons, at my local mall's Black's photo store. The cost was way less than $100, and by doing the testing myself I saved $100 or more perhaps. But I pity the people who bought the other 4 offered for sale. A brief romp through features of importance: 1. Lower power = less shake, brighter, and generally wider field of view. This places a higher premium though on optical quality and optic aberrations. If (like me) you are astigmatic, it is difficult to find optics that give a satisfactory image across an entire low power field. For binoculars larger than I have considered here, higher power may be relevant.
2. More expensive binoculars may be better sealed, or even water-proofed. They thus last longer at their optical peak. Damp, cold, night duty is very different from light daytime summer viewing. Don't forget to cap the lenses outside on a frosty night before bringing them inside. Let the acid dew attack the plastic covers... An Observing Project Enough of this. Lets put the things to work. What to look at? The best starting point is Harrington's Touring the Universe with Binoculars. This is an invaluable compendium of comments and lists --- generally by constellation --- of things to look at through binoculars. Match this with a good sky atlas, like Sky Atlas 2000, or even Uranometria 2000 for big glasses, and you will not be bored through the end of the Millenium. As a cure for the punishing Winter conditions I have started on the Astronomy League's (AL) Binocular Messier hunt. This is organised in groups of difficulty --- depending on the aperture you are using --- and I have had a great time with it. I generally collect up the easier (rated E) objects in my own backyard, and head for darker skies to pull in the Tough (T) and the even more difficult Challenge (C) objects. I have even suceeded in seeing objects omitted from the 11x80 listing (such as M57), presumably because they are considered too difficult. On the other hand I want to spend a lot more time staring at M43 before I decide to log it. It is just so small and lost in the overwhelming glow of M42 at the low power in use. So I include with this article the Spring and Early Summer AL Binocular list (see page 8). The full listing (with a number of appended fields, such as atlas and Harrington page references)is available as a database file from me, for importing to your own database or spreadsheet. Pwr Size(mm) Maker/model Wt(oz) US $ CAN $ Fld deg ER mm EP mm 7 36 B & L Elite 15 $878 8.0 20 5.1 7 42 Celestron Ultima 22 $223 7.0 23 6.0 8 42 B & L PC-3 Elite 28 $929 7.0 20 5.3 7 50 Pentax PCF 33 $154 7.1 20 7.1 7 50 Celestron Pro 28 $149 $195 7.1 19 7.1 7 50 Adlerblick MC 27 $279 $399 7.0 25 7.1 7 50 Celestron Ultima 27 $259 $335 7.0 17 7.1 7 50 Celestron Military WP 39 $336 7.5 17 7.1 7 50 Fujinon FMTSX 50 $486 $575 7.5 23 7.1 10 70 Fujinon FMTSX 76 $589 $775 5.3 23 7.0 NGC RA Min Deg Min Mag Type Con Size Messr Rating Comments 2632 8 40.1 19 59 4.0 Ocl Cnc 95' 44 E 200*, 75>10Mv 2682 8 50.4 11 49 7.5 OCl CnC 30' 67 E >500* 2548 8 13.8 5 48 5.5 OCL Hya 54' 48 E >80*, Tight, Triangle 3031 9 55.6 69 4 8.5 Gal UMa 21'x10' 81 E Oval 3034 9 55.9 69 41 9.5 Gal UMa 9'x4' 82 E Cigar, rift 3587 11 14.8 55 1 12.0 PlN UMa 202"x196" 97 T VL SB, 108 in f 3556 11 11.6 55 41 11.0 Gal UMa 8'x1' 108 C Pencil thin smudge 3992 11 57.6 53 23 11.0 Gal UMa 7'x4' 109 C SBb 5457 14 3.3 54 22 8.5 Gal UMa 22' 101 T May glimpse fnt nuc. WIN4 12 20.0 58 22 9.0 Dbl UMa 49" 40 E Faint pair, mistake 3623 11 18.9 13 6 10.5 Gal Leo 8'x1.5' 65 T Wider oval 3627 11 20.2 13 0 10.0 Gal Leo 8'x2.5' 66 T Easier oval 3351 10 43.9 11 42 11.0 Gal Leo 4.4'x3.3' 95 C Faint, core only 3368 10 46.7 11 49 10.5 Gal Leo 6'x4' 96 C .5 Mv brgtr, core only 3379 10 47.8 12 35 11.0 Gal Leo 2' 105 C Faint oval disk 5272 13 42.2 28 23 7.0 GCl CVn 16.2' 3 E Granlr, 4" resolves 5194 13 30.0 47 11 8.0 Gal CVn 11'x7' 51 T Glow + nuc in * trapzm 5055 13 15.8 42 2 8.5 Gal CVn 10'x6' 63 T Cigar nr 8m * > smudge 4736 12 50.9 41 8 9.5 Gal CVn 7'x3' 94 E Halo ard *nucl 4258 12 18.9 47 19 9.5 Gal CVn 19'x8' 106 T Elliptical glow 4472 12 29.8 8 1 10.0 Gal Vir 9'x7.5' 49 T 2nd brgtst Virgo ellipt. 4579 12 37.8 11 50 11.0 Gal Vir 5.5'x4.5' 58 Easier thn 89, sml dsk 4621 12 42.1 11 39 11.5 Gal Vir 5'x3.5' 59 C 4649 12 43.7 11 34 10.5 Gal Vir 7'x6' 60 T 4374 12 25.1 12 54 11.0 Gal Vir 5' 84 C 84/86, pr of oval disks 4406 12 26.3 12 57 11.0 Gal Vir 7.5'x5.5' 86 C Fainter than 84 4486 12 30.9 12 24 11.0 Gal Vir 7' 87 T Lrgst, *nuc in bin 4552 12 35.7 12 34 11.5 Gal Vir 4' 89 C 89/90, tough pr, minute 4569 12 36.9 13 10 11.0 Gal Vir 9.5'x4.5' 90 C Brgtr, Fnt *nuc + oval 4303 12 22.0 4 29 10.5 Gal Vir 6'x5.5' 61 T Fnt face on spiral 4594 12 39.9 11 37 9.5 Gal Vir 9'x4' 104 T Brgtst, w band suspected 5024 13 12.9 18 10 8.5 GCl Com 12.6' 53 E Small unreslvd puff 4826 12 56.7 21 41 9.0 Gal Com 9.3'x5.4' 64 T Oval patch, Blackeye 4382 12 25.5 18 12 10.5 Gal Com 7.1'x5.2' 85 C *nuc & fntr halo 4501 12 32.1 14 26 11.0 Gal Com 7'x4' 88 C Tilted Sb, core 4192 12 13.9 14 55 11.0 Gal Com 9.5'x3.2' 98 4254 12 18.9 14 26 10.5 Gal Com 5.4'x4.8' 99 C Diffclt, nr 7M * 4321 12 23.0 15 50 10.5 Gal Com 7'x6' 100 C Lower SB than 99 4548 12 35.5 14 30 11.5 Gal Com 5.4'x4.4' 91 4590 12 39.5 26 45 9.0 GCl Hya 12' 68 T Small fnt fluff ballThe Astronomical League Spring and Early Summer Binocular Observing List To help in locating some of the objects, I have appended three charts generated using Deep Space 3D (Shareware by David Chandler) with the SAO stars to almost 10th magnitude. The scale on all of the maps is 2 degrees to the inch. The first map (page 9) shows galaxies in the Ursa Major/Canes Venatici region, including M51. The second map (page 10) shows all of the Messier galaxies in the Virgo/Coma Berenices area. Finally, the third map (page 11) shows the Messier galaxies in Leo. Happy hunting. TO BE CONTINUED... |