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Several people responding to my original question suggested I post
a review of this scope. I guess case studies may be useful? OK, here goes: The Bushnell Voyager 78-9440 is a classic trash scope. I got it for free. I paid too much. Still, after some useage it is not completely without good points. This is a simple 60 mm refractor. The optics seem fine to my amateur eye. Although the user's manual says it has ..9" eyepieces, and tells how to use the enclosed adapter with 1.25" eyepieces, my scope actually came with two 1.25" eyepieces in 8 and 12.5 mm. The diagonal is built to take 1.25", and the adapter is for .9" eyepieces. So all I had to do was discard the adapter. This is all to the good. These are no-name eyepieces (literally - there is nothing at all printed on them beyond the focal length), A flimsy plastic-housing diagonal is included, which the manual describes as optional. There is no way to mount the eyepieces without the diagonal. Those are all the good features. They are good enough for observing the Moon. I find that's all I use this for in practice. Although 60mm is sufficient to see other targets, the bad features of this scope make it usuable for finding targets smaller (harder to aim at) than the Moon. The focus rack is good enough, though not as smooth as I'd like. With a little effort I am able to achieve focus that is as good as my aging eyes can tell. I somehow expected a 60mm telescope to bring in dimmer objects than my 35 mm binoculars. I know, with both eyes my brain has more light to work with. But even using the binoculars with one eye, I believe I can make out dimmer objects than I can with this scope. Naturally, I have almost never used the higher-power eyepiece with this scope. It does show more detail in lunar features, but the difference is subtle. A simple plastic Barlow tube and an erector tube also come with this scope. I have never bothered to take either out of its bag. Both the box and the user's manual gush over the hardwood tripod. In fact, the tripod in my box is aluminum. At full extension it is only approximately 4.5 feet tall, which means to aim at anything much above the horizon I have to lie on my back on the ground. The mounting is a standard camera mount with pan and tilt. A nice smooth camera mount is undesirable, but can be used. This is not a nice smooth camera mount. It has both stick and slop. When I find a target I have to estimate how much to offset my aim to account for how much the mount is going to move after I lock it down and let go of it. The manual claims the mount has fine adjustment controls that permit me to track targets as they move. There are no such controls. This mount puts the trash in this trash scope. The second trash feature is the finder. A flimsy plastic 5 x 24 mm scope mounted on the main tube, the finder has only 1 set of 3 adjustment screws. As far as I can tell after months of experiment, there is absolutely no relationship between how I turn the adjustments and how the finder moves. I have been completely unsuccessful aligning this finder with the main scope. The finder, for all useful purposes, does not exist. The result is that I have to aim the main tube by eye. It is extremely difficult to find a dim target with no working finder. This will proabably become easier as I learn the minor stars and become better at star hopping. An unusable mount, an unusable finder, a short tripod, and a user's manual that has little in common with the product make this a mostly unusable telescope. If I had it to do over again, I would not accept this free scope. I won't give it away - I would not saddle somebody else with this lemon. I have not yet brought myself to take it to the landfill, so I'll probably continue to set it up on good Moon viewing nights. So I don't yet own a real telescope. Someday I will buy one. The Bushnell Voyager 78-9440 will definitely make me avoid buying anything with the Bushnell name on it. -- Glenn Holliday |
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On 11/16/03 21:24 +0900, Glenn Holliday wrote:
Several people responding to my original question suggested I post a review of this scope. I guess case studies may be useful? OK, here goes: [ snip ] Your experience with the Bushnell reminds me of my experience using my first telescope (a 50mm Nashica) that, if anything, is worse than your Bushnell. So I don't yet own a real telescope. Someday I will buy one. The Bushnell Voyager 78-9440 will definitely make me avoid buying anything with the Bushnell name on it. Just don't let the Bushnell extinguish your love for the heavens, okay? There are plenty of people here who, when you're ready, will be happy to help you select the right telescope for you at a price you're happy to spend. Till then, keep working those binos! ![]() trane -- //------------------------------------------------------------ // Trane Francks Tokyo, Japan // Practice random kindness and senseless acts of beauty. // http://mp3.com/trane_francks/ |
#3
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Glenn Holliday wrote:
Several people responding to my original question suggested I post a review of this scope. I guess case studies may be useful? OK, here goes: Oh, how reminiscent of a post I made on the 114mm reflector version of the same trash that I posted here on 2001 Jan 14: --- begin repost --- Yesterday evening I went to dinner with some friends whose children were given a telescope for Christmas by a cousin -- they, the parents, wanted me to give it a once-over. The telescope itself is a Bushnell "Voyager" 114mm reflector, approx. f/8, on an EQ-1 type equatorial. I didn't bother with the instruction sheet, but a glance at the tripod and mount was evidence that my friends (both of whom are extremely intelligent and practical people), had not understood the instructions. We sorted that out, then I had a look at the telescope itself. I was appalled at the build quality. The focuser, for example, is entirely made of plastic and has a 0.965" insert into the 1.25" drawtube. There was an enormous amount of slop and backlash, which was impossible to eliminate. The finder is approx. 20mm (more about that later). The supplied eyepieces are 20mm and 12mm Huyghenians and a 4mm SR. There is also a x3 non-achromatic Barlow. I suspected that it would not be collimated, so I peered down the drawtube. It wasn't obviously out, so I removed the 0.965" insert, perforated both ends of a 35mm film can to make a sighting tube, and checked again. It was immediately obvious that the focuser wasn't properly squared on -- but there was no facility for adjusting this. I tweaked the collimation as best I could, took the scope into the garden and set it up, then went indoors for dinner. An hour or so later, I went outside again and tried to point it at Jupiter. Objects are significantly dimmer in the finder than they are to the naked eye -- the derisory aperture is obviously stopped down even more -- I should have checked! There is a small hole/tube in the stalk that holds the finder -- I found it to be more useful than the finder itself. Jupiter was disappointing in the 20mm, so I found M42 -- at least you could see some structure. Next stop Saturn. Well, at least you could see space between the rings and the planet, but the vibration was appalling when I was focusing, even with the 20mm e/p. The 12mm showed no more detail, but did introduce some false colour. This, I am happy to say, did not prevent the exclamations of "Wow!" when people had their first ever views of the ringed planet. The 4mm is essentially useless. I didn't even bother trying the Barlow. I did a quick star-test and was not surprised to find spherical aberration. No-one else fancied braving the cold, so we packed up and went indoors. Throughout all this, I was trying to be extremely tactful -- I don't think that there is much to be gained by telling youngsters that their cherished Christmas present is a crock of excrement. I shall offer to improve it and make it easier to use, but I am appalled! I have used many telescopes in my life, including some that included misconceived ideas of my own that have not exactly been a pleasure once put into practice, but this telescope has to be one of the (if not *the*) most difficult to use that I have ever come across. If I find it difficult, how the heck are people with no experience going to manage? And these are precisely the people at whom this telescope is targeted! Nuff said! Noctis Gaudia Carpe, Stephen --- end repost --- Best, Stephen Remove footfrommouth to reply -- + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + Stephen Tonkin | ATM Resources; Astro-Tutorials; Astro Books + + (N51.162 E0.995) | http://www.astunit.com + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + |
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Oh, how reminiscent of a post I made on the 114mm reflector version of
the same trash that I posted here on 2001 Jan 14: There is no doubt in my mind that such scopes are poor choices and parts of them are very poorly made. I strongly encourage anyone reading to avoid these scopes. So before I get to the heart of what I have to say, let me say this so that anyone doing a google search may find it. Begin: INTERNET Search Engine WARNING: Parents, Friends, Loved Ones, Bosses giving bonuses, whomever might be wanting to give a CHRISTMAS TELESCOPE, Please do not buy scopes at a department store or even some Camera stores. Typically these will be made by Bushnell, Simmons, CStar, Jason and others including some Meade and Celestron Scopes. There are many nice telescopes available. One possibility is Orion (USA) has made some wise choices with their inexpensive scopes so that they provide good values. www.oriontel.com Please feel free to post your questions to this newgroups or Email me privately if you have any questons. END OF INTERNET WARNING. Now on to the heart of my thinking: However I also think that given the choice between one of the Bushnell scopes and nothing, there is quite a bit one can do to improve them. For some this might be the only option, this is the scope they have and I believe that with some attention and a small amount of cash they can be improved to the point where they are worthwhile. There are webpages on this and I will not attempt to cover the subject, I will point out that often the basic optics are not so bad, the mounts need stiffening, the eyepieces need replacing and the finder needs to be replaced as well. Those "5x24" finders have washers in them because I think they have what might be termed a "Chromat" for an objective. So, my real point, if you have one of these scopes and cannot return it, then don't dispair at Stephen comments, take charge and make the best of it. Jon PS: It occurs to me that a Christmas Telescope FAQ might be in order, anybody else agree? |
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Jon Isaacs wrote:
However I also think that given the choice between one of the Bushnell scopes and nothing, there is quite a bit one can do to improve them. Agreed. See: http://astunit.com/tutorials/junkscope.htm Best, Stephen Remove footfrommouth to reply -- + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + Stephen Tonkin | ATM Resources; Astro-Tutorials; Astro Books + + (N51.162 E0.995) | http://www.astunit.com + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + |
#6
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![]() "Glenn Holliday" wrote in message ... Several people responding to my original question suggested I post a review of this scope. I guess case studies may be useful? OK, here goes: The Bushnell Voyager 78-9440 is a classic trash scope. I got it for free. I paid too much. Still, after some useage it is not completely without good points. This is a simple 60 mm refractor. The optics seem fine to my amateur eye. Although the user's manual says it has .9" eyepieces, and tells how to use the enclosed adapter with 1.25" eyepieces, my scope actually came with two 1.25" eyepieces in 8 and 12.5 mm. The diagonal is built to take 1.25", and the adapter is for .9" eyepieces. So all I had to do was discard the adapter. This is all to the good. These are no-name eyepieces (literally - there is nothing at all printed on them beyond the focal length), A flimsy plastic-housing diagonal is included, which the manual describes as optional. There is no way to mount the eyepieces without the diagonal. Those are all the good features. They are good enough for observing the Moon. I find that's all I use this for in practice. Although 60mm is sufficient to see other targets, the bad features of this scope make it usuable for finding targets smaller (harder to aim at) than the Moon. The focus rack is good enough, though not as smooth as I'd like. With a little effort I am able to achieve focus that is as good as my aging eyes can tell. I somehow expected a 60mm telescope to bring in dimmer objects than my 35 mm binoculars. I know, with both eyes my brain has more light to work with. But even using the binoculars with one eye, I believe I can make out dimmer objects than I can with this scope. Naturally, I have almost never used the higher-power eyepiece with this scope. It does show more detail in lunar features, but the difference is subtle. A simple plastic Barlow tube and an erector tube also come with this scope. I have never bothered to take either out of its bag. Both the box and the user's manual gush over the hardwood tripod. In fact, the tripod in my box is aluminum. At full extension it is only approximately 4.5 feet tall, which means to aim at anything much above the horizon I have to lie on my back on the ground. The mounting is a standard camera mount with pan and tilt. A nice smooth camera mount is undesirable, but can be used. This is not a nice smooth camera mount. It has both stick and slop. When I find a target I have to estimate how much to offset my aim to account for how much the mount is going to move after I lock it down and let go of it. The manual claims the mount has fine adjustment controls that permit me to track targets as they move. There are no such controls. This mount puts the trash in this trash scope. The second trash feature is the finder. A flimsy plastic 5 x 24 mm scope mounted on the main tube, the finder has only 1 set of 3 adjustment screws. As far as I can tell after months of experiment, there is absolutely no relationship between how I turn the adjustments and how the finder moves. I have been completely unsuccessful aligning this finder with the main scope. The finder, for all useful purposes, does not exist. The result is that I have to aim the main tube by eye. It is extremely difficult to find a dim target with no working finder. This will proabably become easier as I learn the minor stars and become better at star hopping. An unusable mount, an unusable finder, a short tripod, and a user's manual that has little in common with the product make this a mostly unusable telescope. If I had it to do over again, I would not accept this free scope. I won't give it away - I would not saddle somebody else with this lemon. I have not yet brought myself to take it to the landfill, so I'll probably continue to set it up on good Moon viewing nights. So I don't yet own a real telescope. Someday I will buy one. The Bushnell Voyager 78-9440 will definitely make me avoid buying anything with the Bushnell name on it. -- Glenn Holliday Some people in this group have pointed out that it might be of some use to remove all the glass in the finder and just use it as a crude pointing device. Advantage: everything is now much clearer through the finder and the image is now upright and not reversed . :-) |
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