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Archive for January, 2011

Oh, By the Way – Map Posters

If there is one thing we got asked for a lot in the store, it was maps. Trouble is, while there were some good map posters out there, they were either very expensive, or were not laminated for durability – which made them little better than unfolded paper maps you buy at the gas station. But we finally got a map supplier who we were happy with- and the result are some well detailed, large sized and laminated maps!

First up is the World Map

Well detailed and large sized (51-1/2″ x 37-1/2″) this poster map also has a near complete list of the nations’ flags at the bottom. This map is excellent for home or school!

We are also carrying a laminated Poster Map of the USA

Slightly smaller than the World Map (45-1/4″ x 37-1/2″) this map has pictures of every state in the Union, as well as inserts for Alaska and Hawaii. The USA map is also laminated and a great addition for home, office or school!

Both maps are $19.95 each and in stock.

www.spectrum-scientifics.com

Make Do – A toy of creative building!

The Make Do series of construction toys is based on a very simple idea, and yet it is incredibly versatile: Give kids the tools to make almost any toy they want using a few simple parts and some old cardboard boxes! With the Make Do you can construct lots of great things like this:

 

Make Do Dog

 

The Make Do kits come in different forms, the main one is the simple MakeDo Kit for one.

The MakeDo Kit for One

 

Like the other kits, the set is made of of three different parts:

 

Make Do Parts

The first part, in the center, is the pin system that allows you to join one box to another. The second, on the right, is the hinge which is used with the pin to make swinging joints between boxes. The final part, on the left, is the safe saw that lets kids safely shape and cut holes in boxes to make them how they want. With just these three parts you can make all kinds of neat ideas limited only by your imagination and the number of boxes you can find.  Some ideas are shown here:

 

Santa!

Other kits in the Make Do series are more purpose driven, such as the Make Do Find and Make a Car Kit. Here your kit is designed around making boxes into play cars!

 

Make Do Find and Build a Car Kit

Also fun is the Make Do Find And Build a Robot . Much like the find and build a car kit except this one is oriented towards building robots!

Make Do Find and Build a Robot

You aren’t just limited to the ‘robot’ show in the picture. A couple of examples of other robots can be seen here:

Make Do Alternate Robot

Or  this guy:

Another Robot!

 

Make Do kits are incredibly versatile and really let a kids imagination grow! They bring out the best in construction and let you re-use those empty boxes!

Optical Coatings – Why they are important and what to avoid

Take a look at the front of any pair of binoculars, refractor telescope, or even most sets of eyeglasses and you might notice that they often have a blue, green, or even purplish tint to them. This is a sign of an Optical Coating.

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Optical coatings have vastly improved the quality of optics over the past decades. The reason for their existence is simple: Every time light goes from air to glass it loses as much as 8% of the light due to scattering/reflection. This may not sound like much but when you consider that a basic refractor telescope with an air spaced achromat (lens with two or more elements) and a decent two element eyepiece will have 4 air-to-glass transmissions. So thats ((((100%*.92)*.92)*.92)*.92) = 71.6%. You lose over 1/4 of the telescope’s light gathering power from scattering! That doesn’t include a mirror or prism diagonal which will also lose light! Binoculars have a similar problem, only more so as they have internal prisms that add even more air-to-glass transmissions. (Eyeglasses do not need coatings so much, but they do not cost too much and usually don’t hurt to add).

Hence optical coatings were developed. Coatings do not solve the light scattering problem, but they sure as heck reduce it. A decent coating can reduce the light scattering from 8% loss to around 4-6%. Adding even more layers, or multi-coatings improves the scattering reduction, as does the quality of the coating application. But nothing completely ends scattering.

Optical coatings in lenses are almost always made of Magnesium Flouride (MgFL). They are applied in a vacuum chamber. A single optical coating should have a very subtle blue color when you look at the lens surface at an angle. Multi-Coats will have a green or even purple tint when you examine the surface.

In all, there are several accepted classifications for optical coatings: Coated, fully coated, multi-coated, and fully multi-coated. They are defined as follows:

Coated means that at least one air-to-glass surface in the optical system has an optical coating.

Fully Coated means that all air-to-glass surfaces in the optical system have an optical coating.

Multi-Coated means that at least one air-to-glass surface in the system has an optical multi-coat. The rest should have at least a single optical coating.

Fully Multi-Coated means that all air-to-glass surfaces in the system have mutli-coatings.

There are some variations on this. In Europe optical multi-coats are often referred to as ‘Overcoated’. Adding further to the confusion is that some companies give names to their coatings. Sometimes this is warranted as the coating is somewhat different from standard coatings, more often it is just marketing.

There is a dark side to coatings, the worst of which is the abuse of ‘Ruby Coatings’ on binoculars. Ruby coatings first came out from Steiner Binoculars who are fond of making specialty binocular coatings for specific environments, such as hunting binoculars whose coatings that bring out objects better in foliage, desert coatings for the same purpose in the sandy zones, etc. One coating developed by Steiner had a ruby color. It worked acceptably, but it worked by partially blocking some of the wavelengths of light. The Steiner version did this only a little, but the resulting coating had a problem: It looked cool.

Ick! Ruby Coating!

Since the Ruby coatings looked cool, Hollywood and Madison Avenue started using binoculars in ads and movies with the ruby coatings. This turned out to be a bad thing as many low-end binocular producers started churning out ruby-coated binoculars by the container-load. But there was a problem: Ruby Coatings didn’t give you a very good image.

If you look through a Ruby coated binocular and compare it with a normally coated binocular you will see that it looks a little washed out. The greens and blues stand out too much, the reds are faded. Its like looking at a photo that has had some sun bleaching. This is because the red portion of the spectrum is being deflected by the Ruby coatings, which low-end binocular producers made with brighter and brighter red coatings that dropped more and more red light.

Eventually, it got to the point where you could not have a low-cost binocular without a Ruby coating. But soon the Ruby started to lose its value. Bird watchers knew that the drop of the red colors meant they could not see all the details in their favorite birds, folks wondered why so few higher end binoculars didn’t use ruby coatings if they were so good, some binocular sellers outright spoke out against ruby coatings. Soon many of the ruby coated binoculars started to show up with regular coatings. You can still find ruby coated binoculars, but they are usually sold at the lowest end, sometimes even with bad TV ads. These are usually sold on the basis of their ‘cool’ appearance to those who do not know better. If you encounter a pair of ruby coated binoculars, try to avoid them. They are not worth even their low end pricing.

Want to buy binoculars?

www.spectrum-scientifics.com

New Brass Products

We had a bit of success with some of our previous brass items, such as the small brass sextant and the small brass equatorial sundial that we decided to add a few new brass items to our product line. They look great and are functional!

First up is the biggest new item, a classically designed 36″ Brass Telescope on a wood tripod

This telescope has a fixed 20X magnification and a tripod that extends from 35″ to 62″ tall! It looks great in any room and adds a touch of class! It is also a bargain at only $229.95!

 

The next items are nowhere near as large, but they can still be very impressive. First up is the 3″ Brass Sundial and compass.

3" brass sundial and compass

This sundial/compass has lots of neat features and looks great. It also comes with a wood storage box with brass features!

 

A slightly smaller version of the Brass Compass/Sundial combo is also available:  The 2-1/4″ Brass compass/sundial .

2-1/4" Brass Sundial & compass

This unit does not come with a wood box, but does have a brass lid with a brass ‘calculator’ for determining actual time. The whole unit fits neatly in your pocket!

 

Next up is the  4″ Brass Directional Compass.

4" Brass Directional Compass

Built on a solid wood base, this compass really can impress with its large size and gorgeously carved brass interior.

 

Finally there is the liquid-filled 2-1/4″ Brass Compass.

2-1/4" Brass B/W Compass

Almost downright utilitarian by comparison to the other brass items, this compass still looks great! The interior markings are a nice contrasting black and white surface and the liquid filled compass ensures no excess ‘wobbles’ when moved!

 

These brass items make great gifts and yet are quite functional as well!

 

 

 

Dmitri’s Neighborhood -A book on feeling at home with chemistry basics

Dmitri’s neighborhood is a book on the basics of chemistry written in a low-stress way to learn chemistry concepts. Written by Marti Trudeau, an author local to Spectrum Scientific’s store.

 

 

Working with the concept of the periodic table (developed by Dmitri Mendeleyev – hence ‘Dmitri’s neighborhood) the book walks easily and amusingly through the basic elements and covers topics such as chemical formulas, atoms, electrons, and much more.  Concepts are covered in an easy to equate style so that students can learn easily – the world of chemistry is presented in a manner as if you were walking around a neighborhood and meeting the neighbors (elements). Over 150 pages along with appendices covering the details about the elements. This is book is a great way for junior or senior high school students to learn about chemistry.

The New Benchmark Orbi-Shaker C02!

Benchmark Scientific has done it once again! They’ve already neatly filled the orbital lab shaker market with a great series of products like the Orbi-Shaker, the Incu-Shaker and the low-speed Orbi-Blotter among others. But now they have also added the Orbi-Shaker CO2.

(more…)

The Star-Naming Scam – It’s Back.

This holiday season was the first in some time that I have not heard radio ads for the ‘gift’ of ‘naming a start after them’.  Well, maybe I just wasn’t listening to the radio enough because I did hear one, and its just as bad as it ever was.

OK, let’s just go over the facts right now: Stars are not named after people, stars are ‘named’ by all sorts of designations. The brightest have kept their arabic names., but the fainter ones are named via designation, which usually means they are numbered.  You can’t just walk into  the International Astronomy Union and throw down a few bucks and get a start named after you! They don’t do that, and consider it crass enough to put up a page over the matter.

 

So what do these Star Naming groups do? Well they actually proudly tell you how little they do: They put the name in a book. That’s it. That’s all. Give us $20 and we’d happily put your name in a book as well. But what is their cincher? Well in the ad I heard they register the book with the US copyright office. Wow. The way the guys says it implies that means something to him, but as for astronomy it means nothing. I can produce a Star Atlas with every star name changed, and I can even register it with the US copyright office – but all that means is that no one can copy my book and make money off my new name Star Atlas. It doesn’t mean anyone with a telescope is going to start calling Rigel ‘Fred’. Even if it meant anything in the US, the rest of the world would hardly care a bit.

 

For the record, in older radio ads, the book was said to be registered with the US Patent office, I suspect the patent office took offense to being referred to in this manner.

 

The rest of these star naming nonsense adds on a few extras to make it seem like a bargain. In reality you are just getting a cheap astronomy kit at very inflated prices. The typical items are: a Certification Sheet (easy to print), an astronomy program (there are many freeware programs that are probably superior) and sometimes a book. The quality of the book is unknown, but I cannot imagine it is one of the better books on the market.

 

So if you really want to do something like this, consider ‘adopting’ a star. Many non-profit groups have star adoption programs to raise funds. You don’t get the cheap software, but you do get a more accurate Certificate (although you have to print it). Our personal favorite is the Pale Blue Dot which helps the Kepler planet spotting project continue. Here you are looking at candidates for adoption that are not only stars, but that might have planets orbiting them!

 

Don’t fall for the ‘naming’ scams. Let this nonsense end.

 

 

 

 

We’re Back!

Well, our store blog was removed thanks to some new policies by our hosting company. Attempts to put it elsewhere on the website resulted in a rash of other issues, so we have decided to just go with the basics and use a wordpress domain to get things going again.  We haven’t had a chance to fix all the links or customize this blog much, so bear with us as we rebuild our blog from the ground up!

Spectrum Scientifics Telescope Buyer’s Guide

Spectrum Scientifics Telescope Buyers Guide

There are several telescope buyers guides available on the Internet, some good, some not so good. At Spectrum we are writing from our experience with customers and hope to make this simple and helpful.

Towards that end, the first and in some ways only rule of telescopes is:

Aperture is King!

Aperture is the diameter of the main lens or mirror of the telescope. The bigger it is, the more light the telescope gathers. Do not judge a telescope by its magnification, and stay away from any brand of telescope that sells itself on excess magnification claims (300x!, 600x!, etc.). This is sure sign of poor quality.

More light gathering means better, brighter images, assuming all other things being equal. Decent commercially sold telescopes usually start about 60mm in size (about 2.3”) and go to 20” diameter or more. Roughly speaking, every 2 extra inches of aperture doubles the light gathering capacity of the telescope.

The big problem with getting more aperture is that it increases the size and weight of the telescope. Having a huge, giant telescope with lots of light gathering power has little benefit if it is so heavy you never want to take it out and use it! A minor, but critical caveat to the ‘Aperture is King’ rule is that the small, portable telescope that gets used all the time is more powerful than the giant telescope that never gets moved out of the garage.

What Kind of Telescope?

There are three types of telescope: Reflector, Refractor, and Cassegrain. For beginners purposes, only the first two should be seriously considered. Cassegrain telescope are very nice, but are a bit advanced for first time scope buyers.

Reflector telescopes use parabolic or spherical curved mirrors to gather and concentrate light. The advantage of reflector telescopes is that they are the most economical for larger sizes. The disadvantages are: in inverted image (meaning a reflector telescope cannot be used for looking down the street) and a need for occasional maintenance: the mirror must occasionally be aligned, or collimated to ensure the telescope is working at its best.

Refractor telescopes use two or more lenses to gather and bend (or refract) light. The advantage for refractors is that, at equal sizes, they provide a more crisp image of the object being view versus a reflector telescope, refractors also can be used for terrestrial viewing (i.e. Looking down the street again), and they do not need to be collimated like reflector telescopes. The disadvantages to refractor telescopes is that as refractor telescopes get larger, they increase in price at a much faster rate than reflectors. At smaller sizes, say 2-3” in diameter, the prices are roughly equal for reflectors and refractors. But by the time you reach a 5” aperture, the price of the refractor will be at least double that of the reflector.

Due to the difficulty of grinding larger lenses, the weight of those lenses, and an optical effect called chromatic aberration (where the light is broken up as it travels through the refractors lens in a manner similar to prisms) refractors generally are not made larger than 5-6” in diameter.

What Kind of Mount?

Any telescope is going to need a mount! There are three different mount designs to consider: altazimuth, equatorial, and dobsonian. Whatever mount you decide on, it should be strong enough to hold the optical tube without wobbling. Nothing is more annoying than trying to view an object in the sky, only to have it bounce around and be unwatchable because of a poor mount.

Altazimuth Mounts:Altazimuth mounts are simple mounts designed to help aim the telescope in simple up/down (altitude) and left/right (azimuth). Altazimuth mounts are simple and intuitive, and work well for beginners. They are also useful if you wish to use your telescope for terrestrial viewing. The problem with altazimuth mounts is this: objects in the sky do not move in convenient up/down, left/right motion. They move through the sky in an arc (or at least it seems that way to us!). This means that trying to track celestial objects using an altazimuth mount can be like drawing a curve with an etch-a-sketch! For most beginner viewing, this is not an issue, and one can always reacquire an object that moves out of the field of view. But it does mean that if you find a nice object with your telescope, and leave to go let your friends know, it will likely move out of the eyepiece view by the time you come back!

Equatorial Mounts: Sometimes called German equatorial mounts, are distinguished by their counterweights that are needed to keep the telescope properly balanced. Equatorial mounts require more setup than altazimuth mounts as they must be adjusted to your latitude and aimed North. They are also not as intuitive to aim as altazimuth mounts as they do not follow left/right up/down motions but instead move along declination and right ascension. This follows the path of stars, planets, and deep space objects, but takes some getting used to. The advantages of equatorial mounts are that they can track objects with a turn of a knob, or they can even be motorized. The other advantage is that with some study, the equatorial mount’s setting circles can be used to actually find objects in the night sky! Equatorial mounts are also required for any type of astrophotography, but for beginners this should not be a great concern.

Dobsonian Mounts: Some consider the Dobsonian to be just variant of the altazimuth mount, and they are not completely wrong. Dobsonians have the same advantages and disadvantages of altazimuth mounts: intuitive movement, no tracking, etc. But the difference is that a Dobsonian mount uses a lazy-susan style platform to move in azimuth and usually some form of hubs to move in altitude. The result is that a Dobsonian mount can handle much, much heavier optical tubes than most altazimuth tripod mounts are capable of handling. Thanks to several improvements in design, Dobsonian mounts have become more and more popular as they are one of the most economical telescope designs on the market today.

Other Considerations:

The optical tube and mount are major concerns, but they are not the only things one should consider when buying a telescope:

Eyepieces: Eyepieces are often overlooked when buying a telescope, but they should be considered seriously by the beginner as they are 50% of the overall optical system. Almost all telescopes include 2 eyepieces, but by no means are all eyepieces created equal. Cheap telescopes usually include old, cheap eyepiece designs such as Ramsden or Huygenian designs that actually can make the image worse. The telescope you buy should come with eyepieces that, at a minimum, are Kellner or preferably Plossl design. These eyepiece designs are considered the standard for decent eyepieces.

Finder Scope: Every telescope needs a finder scope, a small telescope that sits on top of your main optical tube and aids in aiming the telescope. Most lower end telescopes these days use a reflex finder which projects a red dot onto an optical window to show where the telescope is pointing. These reflex finders are actually easier to use than a cheap finder scope would be. However, for larger telescopes a 6×30 (which stands for: 6 magnification, 30mm aperture) finder scope is much more appropriate. Larger telescopes may also have even larger finder scopes. Avoid telescopes with old 5x finder scopes, or at least be willing to try and attach some sort of reflex finder in its place.

Optional Accessories: Not everything you need for observing the night sky will come with your telescope (and if it does, beware, some companies gussy up cheap scopes with cheap accessories!). There are some things that should be in any astronomer’s ‘kit’. Such as:

  • A Planisphere

Make certain this is one you can read easily at night with your red flashlight!

  • A Red Light Flashlight :

A red flashlight prevents you from losing your night vision the way a regular (white) flashlight would.

  • A Barlow Lens

A Barlow lens is a lens you slip your eyepieces into that then doubles or triples their magnification. Having a barlow is like doubling the number of eyepieces you have. Make sure you have a barlow before you go buying additional eyepieces.

  • A decent Astronomy book

Don’t just buy a book with pretty pictures. Make certain it is a useful book that gives helpful instructions and advice on how to use your telescope, find& observe night-sky objects and other hints. Make certain to read it fully before you go observing, then refer to it during your observation session.

  • Time and good weather

Make certain that you have time for your new hobby. It takes some commitment for even casual viewing. Also, make certain that before you go observing that the weather is decent for viewing. There’s no point in going observing on a night where haze clouds everything in view!

  • Warm clothing

OK, you should really have this stuff already. But it is important to know. Even in warm summer months the temperature can get surprisingly cool at night. Be certain that you are ready for the weather, wherever you are and whenever you observe.

Other accessories you should consider, but are not as crucial as the above items are:

  • FiltersThere are a lot of filters available, and they all help with viewing certain objects. Moon filters cut down on the bright moon (which can actually be painful to view through a large telescope!). Color filters help bring out features of the planets. Sky Pollution filters reduce (but do not eliminate) the effects of light pollution. Read up on their effects and decide if any of these filters are right for your needs.
  • A Carrying Case (for accessories)Eyepieces, barlows, filters, books, & planispheres! All these little parts can be hard to carry and just shoving them into a bag isn’t a very good idea. Consider buying an accessory case to put your eyepieces, etc in for easy transportation. The time to consider getting a carrying case is when moving the accessories is starting to get in the way of your night sky enjoyment.
  • Binoculars!
  • If you haven’t already gotten a full sized pair, you should. Binoculars make for easy viewing, help find night sky objects. And are great for quick viewing. These need not be specifically astronomy binoculars, just a decent pair of full-sized binoculars will work fine.

Things Not To Worry About

There is plenty to consider when buying your first telescope, but some things should not be worried about. These include:

Astrophotography:

Astrophotography, even in the age of digital cameras, is pretty advanced stuff that requires a lot of time and equipment. Trying to jump into it, or making your telescope buying decisions based on it, is like learning to swim by jumping into a the deep end of the pool. First make certain that you enjoy astronomy, and can commit the time for basic viewing before you even consider taking up astrophotography. Remember that if you need a different mount than what you initially buy as your first telescope that you can usually sell the old telescope at a reasonable price.

Ultra-High End GPS Super GoTo Computer Guidance Systems:

These systems, while great, can actually be problematic. They are expensive, aren’t the ‘idiot-proof’ systems some folks make them out to be, they limit you from learning about the night sky, and many designs actually require that you aim with the computer. This means if the computer’s motors run out of battery power, you can’t even aim the telescope yourself! Basic guidance systems, such as the Orion Intelliscope line are useful for finding objects in the night sky without taking the experience away from you! Consider these instead of completely controlled systems.

Color!

If one were to look through a book of astronomy picture you would think that every view of the night sky through a telescope is awash in bright, pretty colors. Sadly, this is not the case. Most of these photos are taken with long exposure photography and show colors that, while there, are not apparent to the human eye. Be realistic about what you see, and make certain that the telescope you buy doesn’t have tons of unrealistic photos on its box (which were usually taken by the Hubble Space Telescope or the Viking and Voyager probes!).

Above all else BE READY TO ASK QUESTIONS!  Ask your local salesman, ask for advice online. Don’t be shy! Amateur astronomers may be opinionated but they are more than happy to share their experiences and expertise with you!

www.spectrum-scientifics.com