25 Feb Going loopy! Take a closer look at magnification
Why are loupes SOOO expensive?
The answer to that is obviously that there are loupes, and there are loupes!
We thought we’d have a quick tour of some manufacturer websites and brochures that we’ve collected and let you see some of the cool, not so cool, and down-right weird offerings that are designed to enhance your vision.
Fitting
The first thing to remember is that your loupes are precision optical instruments. And like any optical instrument, their effectiveness is dependent on how well they integrate with your own vision. And that, in turn, means they have to fit right, and they have to fit consistently. Essentially, if they aren’t set-up to be directly in front of your eyes they won’t work properly, and if they move around on your face then that relationship will be altered (so they won’t work properly).
Fitting is the reason that the best loupes are custom made and fitted to you. And the greater the magnifying power of the loupes, the more important it is to ensure they are correctly set-up for you.
So there are two things you need to consider in the fitting. The first is obvious. Choose the frame and style that feels most comfortable for you. And remember that you have to wear them all day. Do you, for example, need a built-in light? If so, would a frame with batteries built-in give you more freedom of movement, or would they become heavy during the course of the day.
And what if you wear a head covering such as a turban or a hijab? Can you take your loupes off and replace them easily? Will the arms fit over your head covering or under it?
The second fitting consideration is how accurately the supplier measures your eyes. As we’ve already said, the higher the magnifying power of your loupes, the greater the need for accurate fitting to ensure you can see clearly through them without straining your eyes.
To flip up or not flip up?
Do you need corrective lenses for normal vision? Do you wear contact lenses or glasses? This is definitely something to consider. Loupes manufacturers can correct your vision through their lenses, but do you want to replace your lenses with glasses every time you look away at your computer or wish to talk to (for example) an under-age patient’s parents? It could be that a flip-up style is the answer.
However, if your work means you need very high magnification, flip-up loupes might not be appropriate. Not only are they going to have compromises (however slight) in their fit to your eyes, they will probably be very unbalanced and possibly heavy to wear.
It’s worth bearing in mind that through-the-lens loupes can weigh as little as 30g, while a flip-up design might weigh two or three times as much.
Light it up
As mentioned above, do you need a built-in light? Even the latest high-powered LED lighting will add weight to your loupes, and possibly make them feel unbalanced. Wireless models will house the batteries in their arms, whereas lights powered by an external battery will add the hassle of cables around your neck and a battery pack in your pocket.
There’s one other thing worth noting, particularly if you are working with cosmetic dentistry, or if you are fitting crowns and the like. Colour-light balance.
All lamps will produce a slightly different spectrum of light. Some will have a red-shift or a blue-shift away from the generally accepted spectrum of natural light (although many factors affect even this). The upshot is that it changes the colour of the things it shines upon (or strictly speaking, the clour they reflect).
Different materials are affected in different ways. So a red-shift might mean that ceramic looks whiter than natural teeth, or a blue-shift might make some composites look grey. Loupe manufacturers such as Orasoctic have realised this and are now offering colour corrected lamps with their loupes.
TTL, Gallian or Prismatic
Different types of lens have their own pros and cons.
Gallian lense
Pros
2x – 3.5x magnification
Compact – short
Light
Good depth-of-field
Good field-of-view
Cons
Maximum magnification “only” 3.5x
Prismatic lens
Pros
4x – 8x magnification
Sharpest image
Higher magnification
Cons
Very long
Heavy
Small depth-of-field
Narrow field-of-view
Don’t stand so close to me
The working distance of a pair of loupes requires some advance thought too. It affects the area that is visible and the focus. A loupe with a long working distance will have a larger depth of sharpness. A loupe with a lower magnification factor will also have a greater depth of field and a wider field of view.
As is usual in life, if you want both greater depth of field and higher magnification it all gets a bit pricey. This is because of a whole bunch of physics that is too complicated to bother with here. Suffice to say, greater sharpness, fewer visual aberrations and distortions, greater magnification, wider field of view, and a greater field of depth all work against cost – you rarely get something for nothing, and you certainly don’t get EVERYTHING for nothing.
Over the net or in person?
If you haven’t already worked out the answer, it depends on what you want to pay, and what you want from your loupes. For high-end, all-singing, all-dancing loupes that fit perfectly and won’t strain your eyes when you use them, talk face-to-face with a specialist such as Orascoptic. They often attend trade shows and conferences and can take a fitting and specify the loupes of your dreams there and then. Orascoptic also offers a useful buying guide.
On the other hand, if you know the dimensions you need (including Inter-pupillary Distance (Near PD)) and details of your normal vision prescription, you could try a supplier such as The Loupes Company who claim to save you hundreds of pounds by avoiding face-to-face infrastructure costs. But make sure you know what you want …
Fancy kit and funny stuff
Enough of the boring technobabble. Here are some of the products we found on our travels around trade shows and the internet.
Why Pearl?
Pearl provides the most complete support for the whole patient journey. The marketing team go to many exhibitions and conferences each year, and we found ourselves interested in loupes, and particularly the diverse pricing strategies. So we thought we’d share what we’ve found out along the way.
For more information about loupes, try the buyer’s guide from Professional Dentistry: What to Look for When Buying Dental Loupes.
For more information about Pearl and what it can do for your practice, please call us on 0116 275 9995 or email us at info@bhasoftware.com.