Ot- do readers effect unaided focal length in our eyes- welding helmet magnifiers. - Page 2
Close
Login to Your Account
Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 53
  1. #21
    Join Date
    Aug 2012
    Location
    California, Central Coast
    Posts
    4,041
    Post Thanks / Like
    Likes (Given)
    2226
    Likes (Received)
    1589

    Default

    Does using magnifier lenses also "magnify" the amount of harmful welding light that can damage your eyes?

  2. #22
    Join Date
    Mar 2009
    Country
    UNITED STATES
    State/Province
    California
    Posts
    5,339
    Post Thanks / Like
    Likes (Given)
    97
    Likes (Received)
    1013

    Default

    The muscles can only do so much. The lens becomes less liable with age. A lens replacement sounds scary to me.

  3. #23
    Join Date
    May 2005
    Location
    AZ
    Posts
    2,372
    Post Thanks / Like
    Likes (Given)
    221
    Likes (Received)
    806

    Default

    Brief note about optical principles: The discussion about "more light = better" is demonstrating the fact that the smaller the aperture used for image formation, the sharper the detail. With less light, the iris opens up to let more light in. If the object lighting is bright, the iris is stopped down, and the image quality becomes sharper (think pinhole camera). Higher contrast is also helpful, when it occurs with stronger lighting.

    I have a cataract forming in my right eye, according to my optometrist. Very annoying. My eyes have been a source of frustration for about the last 20 years, ever since I got into my mid-40s. I had very stable vision for quite some time, but now it seems like I need a new prescription about every 8 months. I am not a welder, though, and don't have those worries.

  4. #24
    Join Date
    Jun 2008
    Location
    Bellingham, WA
    Posts
    4,097
    Post Thanks / Like
    Likes (Given)
    987
    Likes (Received)
    2232

    Default

    Ok, I don’t know the OP from Adam, but I would be willing to bet he is about 45 to 50 yrs old. At that age the lens stiffens and just will not respond as well to the muscles that focus it when younger. Bright light helps by “stopping down” the pupil just like stopping down a camera lens improves depth of field. Get used to needing magnification. It is a sign of having successfully navigated all the dangers that have tried and failed to kill you to date. Eye exercises just won’t work. Oh well.... I like 1.5 to 2x for welding and most general close work. 5x is great for working on things like watch mechanisms.

    Denis

  5. #25
    Join Date
    Jan 2005
    Location
    Houston
    Posts
    5,865
    Post Thanks / Like
    Likes (Given)
    583
    Likes (Received)
    2668

    Default

    "Crap - what?

    I have decent gear and use it- this is not my trade so not a lifetime of exposure but really- eye structure being degraded by welding even with good helmet etc?

    The first survey thing I found:

    Is Welding Bad for the Eyes and How to Protect Yourself - Welding Insider

    I am becoming a decent tig man and want to use this capacity in shop as needed but don’t want to screw up my eyes either. "


    I should be clear - my medical training is limited to the privacy of my tool shed. But...it stands to reason that any helmet is not going to render the effects of welding 100% harmless. So let's say a helmet cuts out 99.5% of the harmful stuff. There's still .5% doing its damage. That might not matter to some people, but to others - who already have eyesight issues - every bit counts.

    It's like how they say every ounce of alcohol kills XX brain cells - but you have a billion brain cells so you can get away with it. Still, those XX brain cells mighta come in handy later in life.

    Another topic not mentioned is 'secondhand flash'. The light getting under your helmet can be just as bad. When I do weld, I make sure the dark blue Miller jacket is buttoned up to my neck to cover my typical light colored shirts. If I don't, the light comes in under the helmet.

  6. #26
    Join Date
    Jul 2003
    Location
    savannah, jaw-ja
    Posts
    1,767
    Post Thanks / Like
    Likes (Given)
    1282
    Likes (Received)
    425

    Default

    Not meant to be a de-rail, but abut eye health. I'm 61, Always had pretty good eyesight, yes, I now use readers.
    I also have an auto-immune condition that affects my eyes sometimes, uveitis or "Eel's disease". So I see an ophthalmologist regular for checkups.
    I went in for my regular checkup a couple months ago, right after reading the chart they check your eye pressure. Mine had always been good. Nurse thought maybe her "checker" was not working right, so they took me in another room with a fancier pressure checker. They checked it there, nurse turns around and says:
    "Do you have a history of glaucoma in your family?" !!!!!!!!!! No, I don't, but my pressure was WAY up, and that causes glaucoma.
    Doc told me the fluid goes into the eye, then goes out through the "corners". My corners had closed up. He did a laser proceedure on my eyes to create another way for the fluid to get out, not a big hairy deal. Now all is well.

    Moral of this is get thee to an ophthalmologist for eye check-ups. I almost cancelled my appointment because I could tell the uveitis wasn't happening. Could have caused me to loose my sight if I had done that.
    I also learned than long term steroid use can make your eye pressure go up, and such use is a common cause of glaucoma.

  7. Likes JoeE. liked this post
  8. #27
    Join Date
    Nov 2007
    Location
    marysville ohio
    Posts
    9,580
    Post Thanks / Like
    Likes (Given)
    2751
    Likes (Received)
    6384

    Default

    I have worn bifocals for years. no magnification on the main part of the lens. I think about 2.5 for close up small stuff. About 2 weeks ago it all changed. now I tip my head back to be able to focus even 10' away and I need to use a magnifying glass to read a micrometer. At the same time I got a little unstable walking. I wonder if the 2 are related?

  9. Likes JoeE. liked this post
  10. #28
    Join Date
    Nov 2003
    Country
    UNITED STATES
    State/Province
    Texas
    Posts
    5,193
    Post Thanks / Like
    Likes (Given)
    184
    Likes (Received)
    1664

    Default

    I am not a doctor, but as far as I know, your eyes do not adopt or change to the lenses you use. If they did, eye doctors could prescribe lenses that go in the opposite direction and correct your vision, much like braces correct a person's bite. But that just does not happen. Besides even if you are a professional welder who is working double shifts, you can not possibly spend more than five or ten percent of your waking time with that welding mask in your line of vision. Most of your time will be spent without that mask in position.

    That being said, your eyes can and probably will change. That's why a person's eyeglass prescription will change from year to year. Back in my school days I was near sighted. I had trouble reading the blackboard when I was seated in the back of the room. I needed glasses for that. But about 15 years ago, at around age 60, I was driving one day and realized that I could see the road and road signs BETTER without my glasses. But I needed glasses for close work. My eyes had gone from near sighted to far sighted. I discussed that with my eye doctor and she confirmed my suspicions. The next time I got a driver's license, I insisted on my eyes being retested WITHOUT MY GLASSES. Surprise, surprise, I passed. Now I can legally drive with no glasses.

    Around the same time I gave some real thought to the need for prescription lenses. I have no special needs. My astigmatic correction is only slight. My eyeglass prescription was just a simple, positive lens and both eyes needed about the same correction. Prescription lenses = $100 and up. Readers = $5 or so. I have been using readers ever since. And this even has a bonus.

    And there was another bonus to using readers. I can select different powers for different uses. Stronger ones for reading and weaker ones for viewing a computer screen, which is a bit further from my eyes than a book would be. It is easy to do this in the store, just view things there at different distances with the various lenses available. I have over a dozen pairs of readers and I just leave them at different places around the house, shop, and in my vehicles. I don't have to carry them around but I do carry a pair most of the time. And I always have a pair at hand that are best for use for the thing I do at each location. All of this has cost me less than a pair or two of prescription lenses. And if I misplace one, who cares? No more "Where did I leave my glasses" panics.

    At the present time I am wearing a pair of readers that I made/modified in the shop. The top HALF of each lens is the perfect power for viewing my computer monitor. The bottom HALF is for reading things on the desk, which are closer. I emphasized the word HALF because commercial bi-focal lenses will divide the lens area into 1/3 and 2/3 areas. This is not a good division, IMHO. The one half works better for me. The present pair is over 10 years old and I am getting ready to make a new pair. I may go with 60/40 or so, but still not the 66/33 division of the commercially available ones.

    I say use any lenses in your welding mask that work best for you and don't worry about it.

    Before dong anything like this, please do talk it over with your eye doctor.

  11. Likes ratbldr427 liked this post
  12. #29
    Join Date
    Apr 2004
    Location
    Modesto, CA USA
    Posts
    7,154
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1219

    Default

    I have read that reading anything other then black type on white background is harder to do. the best is 80% as readable as black on white. Some combinations are less then 50% as readable. many websites still use a odd color for background and it does make it harder to read. I bet looking at an arc against a dark background is one of the worst possible combinations for close observations. Not much to be done about this until they can make arc flashes in dark colors instead of blinding arc white/blue.
    Bill D

  13. #30
    Join Date
    Aug 2006
    Location
    Kansas
    Posts
    2,197
    Post Thanks / Like
    Likes (Given)
    15817
    Likes (Received)
    934

    Default

    My mom told me "you better quit jacking off, it'll make you go blind".

    Not wanting to take any chances with my vision, I told her I'd stop when I needed glasses.

  14. #31
    Join Date
    Jun 2001
    Location
    St Louis
    Posts
    18,201
    Post Thanks / Like
    Likes (Given)
    1957
    Likes (Received)
    3089

    Default

    Quote Originally Posted by jim rozen View Post
    You just 'discovered' the fovea.

    Fovea centralis - Wikipedia

    You have hardly any rods in the fovea, mostly cones. Edge of dark visibility means you are relying on rod cells.

    That has been known for centuries.... you can see a lot of stuff better to the side in the dark.... it's just as Jim R said.... the rods are dark vision, and they are also black and white sensitive, not color.

    It says in Leviticus somewhere that the beginning of the day is when you can distinguish the blue from the white (light blue)..... Same deal... enough light for the cones to pick up color.

  15. #32
    Join Date
    May 2002
    Location
    South Central PA
    Posts
    13,717
    Post Thanks / Like
    Likes (Given)
    2333
    Likes (Received)
    3588

    Default

    Quote Originally Posted by EPAIII View Post
    At the present time I am wearing a pair of readers that I made/modified in the shop. The top HALF of each lens is the perfect power for viewing my computer monitor. The bottom HALF is for reading things on the desk, which are closer. I emphasized the word HALF because commercial bi-focal lenses will divide the lens area into 1/3 and 2/3 areas. This is not a good division, IMHO. The one half works better for me. The present pair is over 10 years old and I am getting ready to make a new pair. I may go with 60/40 or so, but still not the 66/33 division of the commercially available ones.
    Please post pictures or a video when you do. I've toyed with this idea, so far all I've done is experiment with stick on bifocals.

  16. #33
    Join Date
    May 2002
    Location
    South Central PA
    Posts
    13,717
    Post Thanks / Like
    Likes (Given)
    2333
    Likes (Received)
    3588

    Default

    Quote Originally Posted by moonlight machine View Post
    I have worn bifocals for years. no magnification on the main part of the lens. I think about 2.5 for close up small stuff. About 2 weeks ago it all changed. now I tip my head back to be able to focus even 10' away and I need to use a magnifying glass to read a micrometer. At the same time I got a little unstable walking. I wonder if the 2 are related?
    I suggest check your blood sugar level. If it's high, see your GP doctor. If it's not high, see both your GP and your eye doctor.

    My eyes used to change a lot like that before I had my BS under control, I understand that's common.

  17. Likes Rudd liked this post
  18. #34
    Join Date
    Nov 2004
    Location
    Webster Groves, MO
    Posts
    7,466
    Post Thanks / Like
    Likes (Given)
    1899
    Likes (Received)
    3485

    Default

    Quote Originally Posted by specfab View Post
    Brief note about optical principles: The discussion about "more light = better" is demonstrating the fact that the smaller the aperture used for image formation, the sharper the detail. With less light, the iris opens up to let more light in. If the object lighting is bright, the iris is stopped down, and the image quality becomes sharper (think pinhole camera). Higher contrast is also helpful, when it occurs with stronger lighting.
    Not so. The smaller the aperture, the poorer the resolution. See Dawes limit.

    dawes limit formula - Google Search

    Bright light may help you see better and stopping down the aperture increases the depth of field but decreases resolution.

    I set up a Takumar lens with a microscope looking at the image and Air Force resolution charts for a target. With each click reducing the aperture I could see an increase in the blurring of the image. Interestingly, the next to largest aperture gave the best picture and when I went to all the way open, flare jumped way up. Lens designers, even the good ones, often go a stop past best performance to improve marketability.

    Bill
    Last edited by 9100; 02-09-2020 at 12:31 AM.

  19. Likes GregSY liked this post
  20. #35
    Join Date
    Mar 2006
    Location
    jacksonville,fl.
    Posts
    1,183
    Post Thanks / Like
    Likes (Given)
    1013
    Likes (Received)
    392

    Default

    moonlight machine,can be stroke symptoms, not to be taken lightly.See your gp asap.BTDT.

  21. Likes Rudd liked this post
  22. #36
    Join Date
    Oct 2010
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    5,206
    Post Thanks / Like
    Likes (Given)
    4583
    Likes (Received)
    1895

    Default

    I've been wearing glasses, with pretty heavy correction for near-sightedness, since I was about 8. 30 years ago, I started wearing hard contacts, and basically wear them all my waking hours. At about age 52-53, I started having distance accommodation problems for the first time. The problem developed gradually, but eventually I realized that I must take a pair of reading glasses into restaurants so I can read the menus, stashed pairs of readers in all my tool cabinets so I could read fine scales, etc. Now, about 8 years later, I think my accomodation problem has about maxed out. So, it is not that OP's eyes are adjusting to his reading glasses; it's much more likely that his eyes are continuing to change regardless of the glasses.

    When I took some welding courses at the local community college, their shop rule required safety glasses at all times, and I finally gave up swapping between fixed cheater lenses in my helmet, safety goggles, and reading glasses (under the safety goggles). I found a brand of safety goggles with bifocal-style cheaters that I like, and now wear those all the time in the shop no matter what I'm doing.

    To the OP, if you have not already done so, see an eye doctor to find out for sure if this is just the normal aging process. Tell the eye doctor that you do closeup work, have to read instruments, etc., and get a recommendation for reader strength. Different strength reading glasses will be better for different working distances. Reading a vernier caliper is going to require more correction than working on the computer.

  23. #37
    Join Date
    Oct 2010
    Location
    Maryland- USA
    Posts
    3,861
    Post Thanks / Like
    Likes (Given)
    2088
    Likes (Received)
    2378

    Default

    I was at a Mexican place last night with another couple and I tried on some readers my friends wife was using- 1.5’s and seemed the menu jumped into perfect focus.

    Then two remarkably big margaritas and the whole world jumped out of focus.


    I liked the version where I got by without glasses but it seems if I want to do decent tig work I need them now.
    It’s true- I was telling myself after I took the lens out to listen to the arc sound and watching the general puddle width for a decent weld but it’s more true- “you have to see it to weld it”
    This work I’m doing is all 3/16”- 1/4” weld beads- there is a whole lot of fine detail to watch on puddle formation at that size bead that is past what I can resolve unaided at welding distance.
    I also get it about what some are saying about ‘well lit’.
    I was assuming that the arc light was enough- it’s not- I am doing a bunch of overhead fillet work in a shadow from the ceiling shop lights and it makes a big difference to how well I can see the work.

    I think the 2x is too much as Mud said on last page.
    I will reluctantly get some advice on what I need.

    I’m 58

  24. #38
    Join Date
    Jan 2007
    Location
    Norfolk, UK
    Posts
    19,269
    Post Thanks / Like
    Likes (Given)
    14730
    Likes (Received)
    14878

    Default

    Quote Originally Posted by Trboatworks View Post
    I will reluctantly get some advice on what I need.

    I’m 58

    Please do TR ……….I know it's a PITA (and $$$) but at least you'll know - and not be stumbling about in the dark.

  25. #39
    Join Date
    Sep 2002
    Location
    People's Republic
    Posts
    3,740
    Post Thanks / Like
    Likes (Given)
    328
    Likes (Received)
    2397

    Default

    Quote Originally Posted by Rob F. View Post
    That sounds like macular degeneration to me, have you had it checked out?
    Eye doctor sees nothing

  26. #40
    Join Date
    Jan 2005
    Location
    Houston
    Posts
    5,865
    Post Thanks / Like
    Likes (Given)
    583
    Likes (Received)
    2668

    Default

    When your eyesight starts getting bad, you come to realize that 90% of many, many things is all about eyesight. Sports, shooting, machining, working on a car, painting, etc.

    We've all been raised on the homilies about people who, despite being blind, are able to do fantastic things of great beauty and skill. It warms the heart. Chicken Soup for the soul. But that, of course, is bullshit at the core. Show me an actual blind person who says it doesn't suck....

    Anyway, for a little story...there is this guy locally who is blind who rebuilds transmissions for a living. That's right, he rebuilds transmissions. He has a very nice shop, modern and well equipped, and a steady base of customers. He lives in a nice house located further back on the property. Every so often, a nice article in the paper showing how a blind person can do anything a sighted person can, etc. It warms the heart. So after a little while, I start to learn that the shop, and the tools inside - well, they were paid for by government grants. His house, too. He actually 'earns' very little of what he takes in. And the majority of his work tends to be completed and/or re-fixed by all the other local transmission guys who sort of pitch in and quietly un-do all the stuff he did wrong. Being blind..it sucks!


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •