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Thread: how to identify large from short

  1. #1
    OptiBoard Apprentice wilddevil's Avatar
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    how to identify large from short

    From practice i make sometimes mistakes and when a person wants to changr their progressive lens wether the precription was changed or the lens has damaged i sometimes whant to see what lens the person wear. Some pairs of lens ar so damged that the marks cannot bee seen or i do not know what kind of lens is it (marks are changed worldwide and some countries use different from others). Haw can i identify what type of corridor it has long or short?
    I have to mention that i have seen long corridors that are mounted on small frames.i think that people use the minimum requairements as it can be possible smal thant that. +/- 1mm. Olso i have seen small corridors on large frames. What is the easiest way to identify them. Thank you.

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    Graph paper is your friend...that, and a water-soluble marker will allow you to quickly sketch the "appearance" of the optical areas.

    With practice you will quickly discern the subtle differentials of the useful and distortion zones. The "tells" will be the area above the distinctive add area, and the distance beginnings.

    The "shorted corridor" will also have a lack of width, and other notable characteristics, as apposed to the longer corridor types. You will almost be able to identify some brands by looking at its zone characteristics.
    Hope this helps.

    I use a 55 cm by 80 cm graph paper that comes in pad form, for easel work. They are easy to cut, and hang anywhere.
    Eyes wide open

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    Compulsive Truthteller OptiBoard Gold Supporter Uncle Fester's Avatar
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    I always want to see what the person wears before I change it too! If they like it I try not to change it.

    If the person wants to change the lens design what they had before should not make a difference.

    If the lenses are damaged to the point you can not read the markings anything you give them will be better.

    Generally the longer the corridor the wider the middle and near powers will be.

    My experience is Myopes like longer corridors Hyperopes benefit from shorter.

    I do not like doctors who change the focus by adding plus to the add power! No +2.75 when +2.50 is best!!!
    Last edited by Uncle Fester; 05-13-2016 at 12:49 PM. Reason: What mistake??? :) I thought I made a mistake once but I was wrong.

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    OptiBoard Apprentice wilddevil's Avatar
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    My qestion is if the perosn whant ot change the lens wether the frame has broken or he/she needs new prescription and i cannot see the marks. I understand that that graph paper is best. But sometimes the person says he/she has hoya lens, but hoya make multiple progressive (i have to mention that the price is subjective sometimes is promotion amd sometimes is not and in Romania prices rise with 10% every year). If i try to give them something else they may do not like .Thank you

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    One eye sees, the other feels OptiBoard Silver Supporter
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    Quote Originally Posted by wilddevil View Post
    From practice i make sometimes mistakes and when a person wants to changr their progressive lens wether the precription was changed or the lens has damaged i sometimes whant to see what lens the person wear. Some pairs of lens ar so damged that the marks cannot bee seen or i do not know what kind of lens is it (marks are changed worldwide and some countries use different from others). Haw can i identify what type of corridor it has long or short?
    In addition to uncut's visual inspection, try using the lensometer to gauge how quick the power ramps up into the full add. Use different templates with far and near holes to narrow the sample size for a more accurate result.

    I have to mention that i have seen long corridors that are mounted on small frames.i think that people use the minimum requairements as it can be possible smal thant that. +/- 1mm. Olso i have seen small corridors on large frames.
    We use different corridor lengths for the different needs of the wearer, and due to the Rx when it's moderate to strong, in addition to accommodating the frame size. In other words, don't worry too much about the habitual lens design, instead, determine the lens design that provides an optimal visual solution, find a frame that accommodates that lens, and that's it, although advanced to absolute presbyopia usually requires multiple pairs of eyeglasses.
    Science is a way of trying not to fool yourself. - Richard P. Feynman

    Experience is the hardest teacher. She gives the test before the lesson.



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    Quote Originally Posted by Uncle Fester View Post
    My experience is Myopes like longer corridors Hyperopes benefit from shorter.
    Fester, forgive me for dredging up an old post and nitpicking it. Devil's advocate question here---please reply only at your leisure.

    Your sentence here seems to counter what I thought was good practice--favoring short corridors for stong myopes and longer channels for hyperopes. (e.g.: http://www.optiboard.com/forums/showthread.php/58871-With-your-patients-wearing-short-corridor-lenses ) Can you elaborate further on your observation? Or was this maybe an inversion typo? (...which someone could probably find in my posts pretty easily....)

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    Compulsive Truthteller OptiBoard Gold Supporter Uncle Fester's Avatar
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    Quote Originally Posted by Hayde View Post
    Fester, forgive me for dredging up an old post and nitpicking it. Devil's advocate question here---please reply only at your leisure.

    Your sentence here seems to counter what I thought was good practice--favoring short corridors for stong myopes and longer channels for hyperopes. (e.g.: http://www.optiboard.com/forums/showthread.php/58871-With-your-patients-wearing-short-corridor-lenses ) Can you elaborate further on your observation? Or was this maybe an inversion typo? (...which someone could probably find in my posts pretty easily....)
    My Bad!

    I did mix it up- Thanks!

    FWIW For the patients that you know should be in another design but never adapt I'm a fan of the progressive Magic 8 Ball. The patient shakes it up and Viola- That's the lens they're destined to be comfortable in!!!

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    Master OptiBoarder RIMLESS's Avatar
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    Quote Originally Posted by Uncle Fester View Post
    My Bad!
    I'm a fan of the progressive Magic 8 Ball. The patient shakes it up and Viola- That's the lens they're destined to be comfortable in!!!
    Lol...I second that!!!!!
    90% of everything is crap...except for crap, because crap is 100% crap

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