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Archive for the ‘magnifiers’ Category

Smartphone Clip on Macro and Fisheye Lenses in action!

We recently added another Smartphone clip-on lens to our offerings. This is similar to our Universal Smartphone Microscope but the lenses are not s microscope system but conventional camera-type lenses. We thought we would put this system to the test.

First up let’s look at the system: It s a simple clip-on soft-jaw clamp similar to the Smartphone Microscope. It should with all smartphones and even most pads:

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The Lies Magnifier Makers Tell, Part 2 – Progress

We’ve complained about this in a previous blog post. Magnifier manufacturers have been telling some rather big whoppers about the magnifiers they make. Some have been claiming to have 30X power (which is in the microscope range) while having lenses almost an inch across. This is simply not physically possible. For a while it seemed like it was inevitable that it would only get worse – mind the products were good, but the specs were lying, a lot.

But from one of our suppliers we recently received this message in the mail



10 Fun Facts About Magnifiers!

1) Did you know that if your eyes can only focus to within about 6″ in front of them? Anything closer will be blurry. If your eyes could focus you would not need magnifiers!844

2) Magnifiers, sadly, are perhaps the optical product most likely to be abused with false specifications. Many imported magnifiers will list much higher magnifications that they are actually producing. They aren’t bad magnifiers, but they are listed incorrectly all too often. Buyer beware!

3) A simple rule: The higher the magnification, the smaller the lens on the magnifier will be. The smaller the lens, the closer it will need to be to what you are viewing! In other words, if you have  a 10 power magnifier, it will be fairly small in diameter and will need to be very close to whatever you are viewing to properly focus.

4) Magnifiers can have glass or plastic lenses when they are large. Glass is heavy but durable. Plastic is lighter but can scratch easily.

5) Your magnifier can act as a little projector of sorts – if you have a bright window you can make an image of what is outside that window by holding the lens a little bit away from a wall on a darker area of the room.

6) Although almost all lenses used in magnifiers are Double-Convex Lenses (but see below), there is a design called a Fresnel Lens that uses ridges in a plastic sheet to magnify.

7) Some more advanced magnifiers use combinations of lenses, usually 2 or 3, to make the magnified image. The image is usually much better with these lenses than with a single lens. Especially at higher powers. Magnifiers that use 2 combined lenses are called Doublets, while those that use 3 are called Triplets.

8)  Some designs of magnifiers are becoming obsolete – there used to be a whole class of magnifiers designed to examine film negatives in their reduced state. With the advent of digital photography they are no longer needed. Mind you, there is also a class of magnifier called a ‘Linen Tester’  that should also be obsolete but found a market in publishing and other fields.

9) There is some overlap where magnifiers should leave off and microscopes should take over. Although they are two different designs optically they tend to overlap in magnifications from 262010x-20x. Per fact #2 you should be wary of any magnifier that claims to give microscope range magnifications.

10) Yes, you can concentrate light through a magnifier to light a campfire, but it needs to be decently sized! You need a lot of surface area of light to concentrate for it to work. A pair of reading glasses won’t work and glasses for people who are nearsighted are the wrong type of lens.

Sooo, interested in buying magnifiers?


Magnifier Buyers Guide Part 2

Continuing from part 1 of our Magnifier Buyer’s Guide:

What Magnifier Should I Choose?

The answer to this, as you may expect, depends on your needs. There are several categories of ‘standard needs’. You may fall into one of these categories but you might not. Either way, you should use them as a guideline to the magnifier best suited for your needs:

General Usage

If you don’t know the purpose for your magnifier, it is best to stick with medium sized hand magnifiers for your needs. 2x-3x is more than enough power for most folks to examine things closely or read fine print.

Menu Reading/Fine Print Reading/Maps

If you don’t want to wear reading glasses, or find they are not powerful enough for reading smaller text,  a standard hand magnifier should serve Dome Magnifieryour needs, but you might also want to consider a dome magnifier (shown on right). Especially if you plan to do a lot of document reading or close examination of maps.  You may find that a small hand-held magnifier is also useful for reading when you are away from home – a small magnifier can be kept in a purse or pocket.

Medical Eye Issues

This is a tough one – the simple fact is there is nothing available that will give you your sight back if you have serious conditions like Macular degeneration or similar conditions.  Medical conditions are one of the few cases where you want to have as high power as you can get in as large a lens as possible. Double lens magnifiers or Aspherics  the best choices here, but everyone’s needs will be different. This is one place where you might want to go to a store that sells magnifiers and try before you buy.

Hobby Work

If you are doing fine needlework, soldering electronics, painting models, or any of  hundreds of hobbies where close-up examination of points of work may be required, you may need other types of magnifiers to fill your needsDesk Lamp Magnifier: desk top magnifiers might be excellent for your work, or maybe a soldering system known as ‘Helping hands’, or perhaps a magnifier you wear on your head. All of these can be quite useful but only you will know your needs and how to fill them.

Jewelry and Geology

The special needs of jewelers and geologists mean they need magnifiers that have very high power (7x+) and as good an image as possible. When you are examining the cuts on a stone the last thing you want is insufficient magnification or an image where the edges of the gem’s cuts bend up near the edge of the lens. Geologists often require high-power and accurate magnification to spot critical details on samples.

As you can see, there are many different needs and designs when it comes to magnifiers. Be sure to know you needs and how best to solve them when buying a magnifier. And remember: sometimes magnifier makers don’t always tell the truth about their product’s magnification. So be wary, but don’t let that inhibit your choosing a fine product!

Magnifier Buyer’s Guide, Part 1

Magnifiers are useful in any situation where small objects or letters need to Magnifier!be viewed. But not all magnifiers are created equal, and in fact without some guidance you may end up with the wrong magnifiers for the job. This guide aims to help you select the proper magnifier for your needs.


All magnifiers will magnify small objects, but they will vary widely in how they do the jobs. These are some properties of magnifiers you should look for:

POWER (or Magnification): This is how much larger a magnifier makes things. A 2X magnifier makes things 2 times as large, a 5X magnifier will make thing five times larger, and so on. Don’t be seduced by high listed magnification, for one thing we’ve already covered how magnifier manufacturers lie and higher magnification will also effect other specifications, such as:

WORKING DISTANCE: This is a measure of how far you have to have the magnifier from the object being viewed as well as how close your eye should be to the lens. At low powers the working is going to be several inches, but as power increases it drops quickly. By the time you have a 10X magnifier the working distance is less than an inch.

FIELD OF VIEW: This is the total area a magnifier can view. Once again, as power increases this figure decreases. A 2x magnifier can view several inches of area, but by the time you reach 5x it will be only about an inch-and a half. At 10x you will be viewing an area less than half an inch across!

LENS SIZE: This is related to field of view in that the larger the lens the more field of view you will have. But to get higher magnifications you must use smaller and smaller lenses. A 2x lens can be as large as 6″ (and we’ve seen bigger!) but a 10X lens will need to be very small, less than 3/4″ is typical.

All of these features are fundamental laws of optics. You simply cannot get around them. A 10x magnifier cannot be 4″  across and held 12″ away from the subject matter.  Its not going to happen!

There are many other characteristics of magnifiers but they are mostly related to the above specifications.  Instead we will concentrate on the different styles of magnifiers


Magnifiers com in many shapes and sizes A reading magnifier

and the most common design is a classic hand-held magnifier. These are usually large, single lenses (2-5″ across is typical) that are low power and are mostly for reading text or examining small objects. This is the design most people are familiar with when they think of magnifiers. There will be many variations of design and size, as well as features such as illumination or fancy materials (brass is common and attractive). There are too many variations to go in here so we will simply say that most of these magnifiers go from 2x to 5x, with the emphasis at the lower part of the magnification scale


Inspection magnifiers are for closer work on small objects that need high power to be viewed or measured. Inspection magnifiers are higher powered than reading magnifier (4x-10x is common)and may have features such as illumination, measuring reticles, and many differing designs.


Loupes are meant for very close inspection of small objects – in particular jewelry or electronics. They are hand-held or held in the eye by squinting. Loupes tend to be higher powered (7x-12x is typical). The sizes of Loupes, as a result, tend to be small and are meant to be used almost right next to the object being viewed.


Once your get above 12x the line between magnifier and microscope gets blurred.  Very-high magnifiers tend to be very small, very expensive, and sometimes the job can be done more effectively by a portable microscope instead. The magnifications of inspection microscopes (10x-40x) should also be considered when magnifier manufacturers make claims of excessive magnification.


So with this knowledge in mind, we can think of all magnifiers with the same magnification as being pretty much identical? WRONG! Every magnifier is going to have different levels of quality depending on the design.

The biggest issue with magnifiers is edge distortion. Looking through the center of most magnifiers will usually give you a clean image, but as you get near the edge there may be problems with distortion – if you were looking at a piece of graph paper, for example, the lines near the edge of the lens would bend and curve in a poorly designed lens.

With low-power lenses just having a properly designed lens is enough to avoid distortion. But with higher powers it is often the case where you need more than one lens to get the power and the clean image. Doublets, Triplets, and in some cases Quadruplet lenses are used to make a clean edge. More lenses, of course, means more work on the design and construction and so more cost.

Other quality factors come into play at higher magnification designs: lens coatings allow much more light to transmit through the lens and reduce and glare that might come from other light sources. These can also be useful for certain hand-held magnifiers as well, but are not as common.

Coming up in Part 2 – So what’s the best magnifier for me?

The Lies Magnifier Manufacturers Tell…

Every now and then we get a customer in the store who wants a very high power magnifier. Sometimes they bring printouts from other retailers that show some rather….unlikely high -power magnifiers with powers of 20x, 30x, even 50x. We unfortunately must inform them of the truth of these claims. The fact is – what is printed in the copy or actually on the magnifier is not true.

Oh, its not really the other companies fault – they are just going with what they see on the box and on the product. A typical example is this magnifier:

An Example of a mis-listed magnifier

Don’t you believe it!

You’ll note this has a rather generous 30x magnification, which still having a nice, wide 21mm lens width.

Nonsense! The rules of optics are remarkably clear on this – the simple fact of the matter is that the more powerful a magnifier is (the higher its magnification) the short its focal length (the point where light rays passing through the lens meet on the other side of the lens) must be! And the shorter that focal length, the smaller the magnifying lens will be.

Let us elaborate:

A large handheld magnifier that probably everyone has in their drawer only provides about 2-3x and so has a long focal length of about 10″. Focal length equates to something known as ‘working distance’. What this means that you can use the magnifier about 10″ away from the thing you are viewing (this will vary slightly).

However, as you increase the magnification of the lens, the focal length of the lens must be made shorter – this also means the diameter of the lens must also shrink or else your lens will become excessively thick and will have a distorting shape – think of looking through a crystal ball and how messed up that image is. Its a good example of a wide diameter lens with a very small focal length (a ball lens, ineffect).

What this means is that by the time you get to just 10x magnification, your lens is barely over a 1/2″ in diameter. This triplet lens we sell is a good example:


The diameter is just 18mm on this unit, and in order to avoid image distortion the lens is a triplet design – where three lenses are placed together to make a much better image than one lens alone would provide. As you can see, the higher power we go, the smaller the lens is going to get. In reality, our 30x lens shown up top should really be about 4-5mm in diameter. Not a very big lens at all.

Truth to be told, barring some optical tricks (which I can assure these ’30X’ magnifiers do not employ) most magnifiers rarely go above 12-15x in power. That realm is reserved for low powered microscopes, which are a different optical beast altogether.

Unfortunately, big numbers sell, and so manufacturers keep putting unrealistic figures on their products knowing that most people won’t know any better. The real tragedy is that most of these overplayed magnifiers are not bad products! The 30X magnifier shown above is actually a decent 7-8X loupe magnifier. We’re even guilty at Spectrum of carrying a few of these ourselves – but in our product copy we note that the listed magnification is probably not accurate. We wish we didn’t have to do that, but we don’t like lying about a magnifier’s true abilities, we don’t like discarding a decent product, and our complaints to the manufacturer have fallen on deaf ears.

So remember these words when you are looking for a high-power magnifier. Don’t get suckered in by inflated claims and be realistic about what your lens can do!

Want to buy magnifiers?