How To Set Up Tasco Telescope
Amateur Astronomer's Notebook
Tasco Telescopes:
Why they are to be avoided (and how to set up them up)
Update for Nov 2002:
Tasco filed for defalcation earlier this year, and Celestron has been "bought back" by some of the founders of Celestron. Tasco scopes continue to be marketed widely notwithstanding. Some of the Tasco models have shown signs of improvement recently. For example, some of them now come up with 1.25" (bore) eyepieces. Withal, the eyepieces supplied are still of generally low quality. Although the change to ane.25" eyepieces on some scopes is a footstep in the right direction, this alone is non enough to make Tasco a recommended make (in my stance). Tasco markets a huge number of telescopes with all kinds of model numbers. Many of the model numbers appear to be some combination of the lens (or mirror) diameter in millimeters, the focal length, and the maximum advertised magnification. Tasco continues to claim preposterous maximum magnifications for many of their scopes (Tasco does this because they know that most people equate magnification with the "ability" of the scope). Below in this article you will run into that magnification is one of the least important factors to consider when purchasing a telescope!
Too: Previously, I had recommended Orion (www.telescope.com) as a source for good quality replacement eyepieces in the .965" size. Orion has dropped this line of eyepieces, so the only path is to get what is known as a "hybrid diagonal" (described below) and some good quality 1.25" eyepieces. This is actually the better way to become, the downside is that the price of the diagonal is about $35, something that you lot would not take to get if quality .965" eyepieces were still bachelor.
Update for January 2001:
There have been some changes in the low end telescope market. For one, Tasco (a marketer of telescopes that are generally considered the bottom of the butt) has acquired Celestron (a visitor that has a reputation for making some good to fantabulous telescopes). I practise non know the details of this merger just it is astonishing to me that a company like Celestron would want to exist fifty-fifty remotely associated with Tasco. Tasco has a reputation of making almost fraudulent performance claims for many of their telescopes, and Tasco scopes are for the most role amongst the about cheaply made scopes bachelor. Celestron has a long history of making quality products, particularly the United states made scopes (which include the SCTs they are famous for). In any event, I for one will now look at Celestron with a much more disquisitional heart. If I see hints of Tasco quality entering into Celestron products, I will end to recommend Celestron products.
Considering of this merger, it is more than hard to recommend a Celestron telescope (nosotros're talking entry level scopes here) over a Tasco (or like low end telescopic) considering the Celestron entry level scopes may in fact now be Tasco scopes! The entry level telescope marketplace has gone in so many different directions in the terminal few years. Even Meade (another manufacturer of decent scopes) now markets a big number of scopes which are "consumerized" versions of their ameliorate scopes. Such scopes normally provide a cheaper mounting, a cheaper, smaller finderscope, and the ever nowadays bombardment of worthless H20, H12.5 and SR4mm eyepieces, and worst of all, they include a 2x or 3x barlow that isn't even useful as a doorstop!
On the positive side, I have seen some Tasco scopes in the terminal year or and so that have signs of comeback over the typical Tasco (exercise annotation that the bulk of the Tasco scopes are still unchanged). The improvements noted include 1.25" diameter eyepieces and one.25" drawtubes. Also, a few Tasco scopes really come up with eyepieces that are sensible for the scope!!! I even take seen some Meade 4.v" Newtonian scopes that take 2" focusers! This is actually overkill for a scope in this class, because most 2" eyepieces cost more than the entire Meade iv.5" scope...
Please note...
This article is in no fashion meant make you experience bad nor is it intended to insult those who take Tasco (or like) telescopes. The vast majority of people who have these scopes are but starting out in astronomy (and oftentimes caused them without prior cognition), and Tasco telescopes are marketed all over the globe. Hence, Tasco is the only telescope make that many people know. The intent of this article is to try and aid those who have invested money in a Tasco scope and who do non desire (or cannot) return the unit to the retailer.
Introduction
This article will explain why most Tasco telescopes should exist avoided if you are to accept a frustration free introduction to amateur astronomy. And, if you lot have received a Tasco telescope as a gift or if you brutal into the "Tasco trap" and purchased i of these telescopes, this article volition provide data on how to significantly improve the functioning of the unit of measurement at a reasonable cost.
If you are because the purchase of a telescope, you have likely seen Tasco telescopes in most every department and toy shop in beingness. If you do non yet own a telescope, the all-time recommendation is to avoid purchase a Tasco telescope!
What'southward Wrong with Tasco Telescopes?
Tasco telescopes were not always every bit poor as they are today. Back in the threescore'due south and early on 70's, Tasco really marketed a decent product (excluding eyepieces). I have a Tasco 60mm refractor from 1973. It has a metal optical tube, a machined metallic rear cell, all metal focuser with machined metallic focusing knobs, a metal dew cap, and a decent objective lens. The tripod and eyepieces left a lot to exist desired, just at least they were all fabricated of metallic. Many Tasco scopes (particularly the very entry level ones) utilize a great deal of plastic. For the aforementioned (or slightly more) money, a much better telescope of like size tin be obtained (see my folio Excellent Start Telescopes for recommendations).
I of the issues with Tasco is that there are so many variations of their telescope models beingness marketed. Tasco markets telescopes to many retailers; these telescopes range in quality from extremely poor to reasonably adequate equally beginner telescopes.
Another reason to avoid Tasco: they (and other vendors of entry level scopes) often use highly deceptive "advertising" on the products they sell. Any company is in business to make a profit (and this is perfectly acceptable); the problem with Tasco is that they try to make a turn a profit by misleading consumers. Take a wait at virtually any Tasco telescope box, and ane of the first things yous volition probably see is an absurd magnification capability for the telescope. For example, a typical Tasco telescope volition have written on the box "675X Astronomical Telescope". Ask whatever seasoned amateur astronomer and they volition certainly tell you that telescope "power" is not, echo not dependent on the magnification capability of the unit. The diameter of the mirror or objective (or mirror if it is a Newtonian reflector telescope) is the cardinal specification that determines how "powerful" a telescope is. The bigger the lens or mirror, the more calorie-free that the telescope will gather, and the brighter the images. Magnification of a telescope is determined past the focal length of the eyepiece used. By using various eyepiece/barlow lens combinations, most any telescope can exist fabricated to operate at magnifications ranging from virtually 30x to 1000x or more than. However, the useful maximum magnification for most telescopes is about 60x per inch of aperature (lens or mirror diameter). So, the typical 60mm Tasco scope has a maximum useful magnification of about 150x (FAR less than the ridiculous 675x claim...). Proceed in mind however that the vast majority of observing is done using LOW magnification!!!
Getting back to the "675x Tasco Telescope"... many of the telescopes that Tasco markets with this claim are 60mm refractors. Allow me assure you this: the view through a Tasco 60mm telescope at 675x will be absolutely useless. At this magnification, it would accept someone experienced with telescopes just to locate the Moon in the eyepiece! The telescope tripod volition be so shaky at this magnification that nothing more than a fuzzy, dim mistiness could be momentarily detected. Stating that a 60mm telescope can be used at 675x is like saying a Yugo automobile tin practice 200mph (the fine impress might say "When dropped out of an aeroplane at 10,000 feet altitude.")! To put this in perspective, apprentice astronomers with superb world class Astro Physics (make) and Takahashi (brand) telescopes costing over ten thousand dollars rarely use magnification anywhere near 675x!
Newcomers to astronomy often associate the magnification of a telescope with quality. As an example, I had my Celestron CG-xi telescope (an 11" diameter telescope costing near $4000 for the base model) set up at a star party and some young people asked me "How much "ability" is that telescope?" I told them that nether the very best of conditions perhaps 500x (but I also explained that the vast majority of observing is done around 100x or below). They were astonished to learn that such a large telescope was non every bit "powerful" as a Tasco they owned! I have had the same chat on many occasions. People non familiar with telescopes mistakenly believe that the magnification adequacy of a telescope is a measure of its "power". Equally stated before, the "power" of a telescope is directly related to the diameter of its mirror or objective (it is not related to the magnification capability of the unit of measurement!). Tasco "lures in" unknowing people (frequently parents shopping for a scope for their child) past stating a preposterously high magnification for their telescopes. This may be constructive in selling products, but it is one step away from "fraud" in my opinion.
Eyepieces: Most Tasco eyepieces are among the most marginal quality available. Instead of providing one decent quality eyepiece, Tasco typically supplies 2 or 3 marginal to horrible quality eyepieces. Tasco eyepieces are oftentimes of the Huygens ("H") and Symmetric Ramsden ("SR") optical configurations. Huygens is amongst the poorest performing designs (only it is inexpensive to industry). Tasco eyepieces have very narrow apparent fields of view... often 30 degrees or less (most decent eyepieces have credible fields of view of 45 degrees or more). Eyepieces with narrow apparent fields of view make information technology harder to locate items in the heaven. Trying to wait through a narrow field eyepiece is analogous to trying to read a book while looking through a straw. Non only exercise Tasco eyepieces have narrow fields, the "sweetness spot" of the field that is visible is fifty-fifty smaller! Tasco eyepieces utilize minimal (if whatever) optical coatings. To peak information technology off, many of the Tasco eyepiece bodies on the entry level scopes are at present made virtually completely of plastic. To make things worse, Tasco frequently supplies an "SR4mm" eyepiece with their telescopes. This is an eyepiece with a focal length of 4mm; information technology is a very poor choice for a beginner level telescope. Information technology will provide magnification that is out of the useful range for the telescopic, and the "center relief" of the eyepiece is so small that it volition be hard to get your eye close enough to the small hole to see anything through information technology (if y'all vesture eyeglasses you tin can forget about looking through this eyepiece). Many Tasco telescope comes with the following eyepieces: H20mm, H12.5mm, and SR4mm. Sometimes an H25mm is substituted for the H20mm. Eyepieces with higher numbers produce smaller magnifications; these are the just eyepieces you should expect to "run across" anything with (you should always outset with these eyepieces first!). Anyone who tries to use a Tasco telescope with an SR4mm eyepiece will need to have incredible patience and the power to withstand signficant frustration! My personal recommendation: If you are looking at a telescope to buy and you see it comes with an H20, H12.5 and SR4mm eyepiece set, exercise non buy information technology!
Star Diagonal: Tasco star diagonals today are at the bottom of the line in quality. As a comparing, the star diagonal that came with my 1973 vintage Tasco telescope is of cast metal construction, has two metallic prepare screws for securing eyepieces, uses a metal barrel, and has a drinking glass prism (note that a mirror is fine if it is of high quality, however the prism acts as a seal to keep dust out of the telescope, an added plus). Many of the Tasco supplied star diagnonals today use a plastic trunk, a plastic barrel, i metal set spiral, and uses a mirror (at to the lowest degree the mirror appeared to exist made of glass). Note that a mirror can exist superior to a prism, nonetheless I seriously incertitude this is the case with the mirrors in the Tasco diagonals. Overall the diagonal has a very "cheap" look and feel. A design engineer would be hard pressed to detect a way to further cheapen this unit (what'south adjacent... a plastic mirror?).
Accessories: Tasco loads up their telescopes with accessories to make the unit seem similar a better bargain for the consumer. The box volition sometimes merits (nix else to buy, a "complete" telescope package)! The trouble is that the accessories are frequently of very poor quality and of piffling practical use. Ane accessory that it often supplied is a barlow lens. A barlow lens is used to increase the magnification of the telescope; the trouble is that most of the telescopes that Tasco markets practise not demand a barlow lens to reach the maximum useful magnification they are capable of (the exception would be curt focal length telescopes, short being defined every bit less than about 400mm). Tasco barlow lenses tend to be of very marginal quality. Tasco sometimes includes a Moon filter with their telescopes. In fact, none of the telescopes that Tasco markets are big enough to warrant using a Moon filter! Moon filters are generally used with telescopes in the 6" (diameter) range or larger. Finally, Tasco telescopes sometimes come with a solar projection attachment. While this accessory may work, it is included strictly as a marketing heave (consumers equate more accessories with a "improve deal"). If Tasco would leave out all of the actress junk and provide one (or two) good quality eyepiece(southward) instead, their telescopes would have significantly better functioning!
Finderscope: Tasco finderscopes are typically a 5x24 model. This means that they provide 5x magnification and use a 24mm diameter objective lens. However, the lens used in the front of these finders is a single slice of drinking glass (equally compared to the much superior two element achromat). As a result, a miracle known equally chromatic abnormality is very apparent on vivid objects (this admittedly can be tolerated on a finderscope however. But here's the kicker: because the lens is so bad on these finderscopes, some of the ones I have seen use a "field stop" which effectively makes the lens equal to nigh a 12mm diameter lens! Overall, a "normal" 5x24 size finderscope is fine for telescopes in this size category. The problem with Tasco 5x24 finderscopes is that quality of the finderscope is rather poor (all plastic). To add to the problems, the finderscope bracket (again all plastic) uses an inadequate "3 point" locking system. This corner cutting blueprint does not permit the finderscope to stay in alignment. If you have Tasco telescope with this blazon of finderscope, plan on doing a realignment each fourth dimension you take the unit out for an observing session.
Construction: I recently looked at some Tasco telescopes in a department store and I was shocked at the quality of construction. Whereas my 1973 vintage Tasco telescope is fabricated from almost 100% metal components (a number of which are machined metallic), some of the Tasco telescopes at present made apply excessive amounts of cheap molded plastic parts! All of the models I looked at had plastic rear jail cell assemblies, plastic focusers, plastic drawtubes, plastic star diagonals, plastic dew caps, and some even had plastic optical tubes! The tripods were typically wood or metal, but all were rather unstable. Overall the telescopes have a very inexpensive look and experience. I would recommend avoiding any telescope that is mostly of plastic construction.
How to Better the Performance of your Tasco Telescope
Despite their mostly low quality, many people have Tasco telescopes. Young people often receive them equally gifts (no doubt purchased past parents who fell victim to the "675x Power" written on the box). Others are purchased by adults who wanted to get into astronomy but did not know that quality telescopes are rarely constitute in section stores. So what to practice if you have a Tasco telescope and are experiencing the "I can't encounter a #$%**~ thing with this telescope!" syndrome? Chances are that you lot can't render the unit of measurement for a refund. If you are willing to invest some additional money, y'all can better the performance of the telescope significantly. The minimum investment will be about $twoscore (depending on what telescopic y'all have). For some scopes, the amount you will need to spend is more than half of what a new scope would price, so if you are in that situation your options are more limited.
The main reason Tasco telescopes perform poorly is that they ofttimes come up with poor quality eyepieces and an equally poor quality star diagonal. Fortunately, the Tasco objectives (or primary mirror for reflecting telescopes) still seem to exist of decent quality. The upgrades to your Tasco telescope volition consist of new eyepiece(south) and a new star diagonal (note if you have a Newtonian Reflector scope Practise NOT purchase a star diagonal every bit information technology IS Not NEEDED and Volition NOT Piece of work with a Newtonian reflector telescope.
One of the first things you must do is understand and accept the fact that depression magnification is where your Tasco telescope (or whatever telescope for that matter) volition perform at its best. For the typical Tasco telescope, depression magnification means 30x - 40x. On the flip side, the highest magnification that should be used with the typical Tasco telescope is in the range of 90x to 150x. Always call up that most of your viewing volition be washed with low magnification! At 100x, the instability of the typical Tasco telescope tripod will be all you tin can handle (the shaking gets magnified along with the image), plus the object existence viewed will move out of the field faster at college magnficiation (unless you lot have a tracking drive)! The only expanse where the college magnification is really useful is when you are looking at the Moon, planets and double stars (just you will discover it a lot easier to initially locate such objects using a lower power eyepiece).
To determine which accessories you'll demand for your detail Tasco telescope, yous will need to wait up some information on the telescope (fortunately the necessary information is normally marked on the telescope). Specifically yous'll need to determine the focal length of the telescope and also the diameter of the objective or primary mirror. This information is ordinarily located on a sticker nigh the eyepiece area of the telescope. A typical marker might read "D=60mm F=700mm" (another common i is D=114mm F=900mm). "D" refers to the diameter of the objective lens (or mirror) in millimeters; "F" refers to the focal length of your telescope (again in millimeters). You might also come across a marking such equally "F8" or "F11.seven"; this is the focal ratio of the telescope (the focal ratio is oft used when judging the suitability of a telescope for astrophotography, smaller numbers mean less exposure needed). Finally, you volition need to determine what size eyepiece barrel your telescope uses; it will be either .965" or 1.25". To decide which ane yous accept, measure the barrel diameter of ane of your eyepieces with a ruler (the barrel end is typically the "shiny" end, the end opposite that which you lot look through). Here'southward another tip: a 35mm film canister will fit perfectly in the eyepiece holder of scopes which have i.25" eyepieces (they also make peachy dust caps for diagonals). If you can fit a 35mm film canister where eyepieces normally go, you have a 1.25" organisation. Once you accept these basic data listed above, you can determine which items to buy in society to upgrade your telescope.
Upgrade Options: At that place are iii basic paths to choose from when because an upgrade to a Tasco telescope. They are as follows:
- Obtain one quality eyepiece (approximate cost $55) Note: If your scope uses .965" eyepieces you MUST go to the side by side option!
- Obtain i quality eyepiece and a new star diagonal (approximate cost $xc)
- Obtain two quality eyepieces and a new star diagonal (approximate price $150) (Annotation: If yous programme to spend this much you lot might likewise carelessness the upgrade idea as you can get a new telescope for that cost).
REMEMBER: Note that if your telescope is of the reflecting type (uses a mirror instead of a glass lens for the light gathering element) DO Non purchase a star diagonal (it will non work with reflecting telescopes)! Chances are you won't exist able to bring the scope to focus considering of the additional length the diagonal adds to the light path.
Source for Quality Components: There are a number of vendors who offering quality accessories for improving "department store" telescopes. I personally recommend products offered by Orion Telescopes and Binoculars
Which Eyepieces do I Select? If your upkeep allows only one eyepiece y'all should select one that produces a low magnification. If funds allow, another eyepiece can exist selected that produces a higher magnification (note that by "higher" I mean around 100x, not the absurd 675x that Tasco provides!). Eyepieces are available in a various focal lengths (this is the number written on the side of the eyepiece). The magnification produced by an eyepiece depends on what telescope the eyepiece is used in. To determine the magnification that a particular eyepiece produces, carve up the focal length of your telescope by the focal length of the eyepiece. Example: The focal length of your telescope is 700mm and you wish to know what magnification a 25mm eyepiece volition produce. Divide 700 by 25 and you become 28; this eyepiece/telescope combination results in a magnification of 28x.
Path 1: Obtain Ane Quality Eyepiece: Equally mentioned above, if your scope uses .965" eyepieces (or diagonal), you cannot utilize this option (get to path 2 below)! For scopes that have i.25" eyepieces, use the list below (based on the focal length of your telescope) to find the recommended eyepiece:
Path ii: Obtain Ane Quality Eyepiece and a Quality Star Diagonal: Brand sure you know whether your telescope takes .965" or 1.25" eyepieces . If your scope does use .965" eyepieces, you must purchase what is chosen a "hybrid diagonal". A hybrid diagonal fits into a .965" drawtube but it accepts ane.25" eyepieces. If your scope takes 1.25" eyepieces )or diagonal), use the following listing to determine which star diagonal to purchase:
Remember: If your telescope is of the reflecting type (uses a mirror instead of a lens), exercise non purchase a star diagonal!
Equally far as eyepieces are concerned, the recommended choices are the aforementioned as those listed in a higher place for Path i.
Important: Be certain to consider what this upgrade will toll compared to what you paid for the scope. If the upgrades are going to cost more than than about half the cost of the scope you might be better off ownership a completely new scope (ane of decent quality all around). If you lot are in this jam encounter my folio for recommended scopes: Excellent First Telescopes
Path iii: Obtain Two Quality Eyepieces and a Quality Star Diagonal: For selecting the star diagonal run into Path ii; for the get-go eyepiece, see Path 1.
Your 2d eyepiece will be ane that produces a higher magnification, high enough to allow y'all to discern some fine item on things like the Moon, planets and double stars, but non so high of a magnification to consequence in blurry, shaky images. As before, make sure y'all know which size eyepieces (.965" or 1.25") your telescope takes. So utilise the list below to determine the recommended second eyepiece:
Important: Be sure to consider what this upgrade will cost compared to what you lot paid for the telescopic. If the upgrades are going to toll more than almost half the cost of the telescopic you might be better off ownership a completely new scope (one of decent quality all effectually). If you are in this jam see my page for recommended scopes: Excellent First Telescopes
Aid! My telescope focal length is unlike that any you list! Not to worry. Chances are information technology is close to i of those listed above. Just option the 1 that is closest; the exact magnification numbers will be slightly off, but the basic operation will be the same.
Have more money to spend? If yous want to go "one better" in quality, you could consider the Orion Telescopes and Binoculars
Not Just Tasco!
While Tasco appears to exist the most popular brand of "department shop" telescopes, exist enlightened that at that place are others out there besides. Other brands to carefully scrutinize include Bushnell, Jupiter, and Saturn. Even some of the Meade and Celestron telescopes (brands previously known only for the high quality instruments they offered) are nothing more than cheap "mass market" telescopes.. More than likely, if you see the telescope in a section store or toy store (K Mart, Toys R Usa, Wal-Mart, etc.) it is near likely one that would not be the best pick for a kickoff telescope. The merely place I have seen quality telescopes for sale in malls are in "The Discovery Store" (however some of the scopes they sell fall into the "avert" category so be careful).
If not Tasco, what should I Buy?
If you take not however purchased a telescope (or if you want to motion up from Tasco), Orion Telescopes and Binoculars
Commentary
While I do not recommend Tasco telescopes to a beginning astronomer today, I volition admit that I my first telescope was indeed a Tasco. Equally I mentioned earlier however, the Tasco telescope of some 25 years agone was a much amend unit of measurement (specially as far equally physical structure was concerned) every bit compared to well-nigh of the Tasco scopes available today. I did manage to see quite a scrap with my Tasco telescope, particularly after I obtained a adept quality low power eyepiece for it! Of form, back in the mid 1970's the lite pollution problem was far less than it is today. If yous exercise have a Tasco telescope do not permit information technology cause you to give up on astronomy without giving astronomy a "fair shake". If you have a Tasco telescope you are by no ways lone, and yous tin have some passably skilful viewing from the unit if you make the upgrades described in this commodity (or if you cannot beget an upgrade at least use the eyepiece with the lowest magnification). The upgrades described volition practice cypher for the stability of the telescope, merely it will result in a dainty overhaul of the optical performance. Resist the temptation to utilise high magnification! You lot really will see a lot more using low magnification. Any experienced apprentice astronomer volition show to this argument.
A reader did write in and made a suggestion for improving the stability of Tasco tripods. Basically you lot add weight to the tripod. To do this, hang a weight (5 to ten pounds) from the middle of the tripod (brand sure to keep the centre of gravity low to avoid having a topheavy scope). I have not personally tried this upgrade but I do believe it will work.
It is hoped that this commodity will save some of the people who might have otherwise given upwardly and dropped out of astronomy due to sheer frustration acquired by a Tasco (or other like) telescope. The people of Tasco will not similar this article to exist sure, but I practise not like to encounter so many people (particularly young people) having so much frustration with a telescope that promises also much!
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