Author Topic: Am colour blind, need help identifying bands  (Read 6194 times)

0 Members and 1 Guest are viewing this topic.

Offline SiliconWizard

  • Super Contributor
  • ***
  • Posts: 15797
  • Country: fr
Re: Am colour blind, need help identifying bands
« Reply #50 on: August 26, 2022, 10:44:55 pm »
Uh. AN eye doctor with no testing for color blindness? Really? They need to change eye doctors.
 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 28429
  • Country: nl
    • NCT Developments
Re: Am colour blind, need help identifying bands
« Reply #51 on: August 26, 2022, 11:03:01 pm »
Uh. AN eye doctor with no testing for color blindness? Really? They need to change eye doctors.
Not an eye doctor, just the generic doctor. But the generic doctor didn't see any need to forward to an eye doctor.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline 25 CPS

  • Frequent Contributor
  • **
  • Posts: 570
  • Country: ca
Re: Am colour blind, need help identifying bands
« Reply #52 on: August 27, 2022, 12:50:39 pm »

This is a bit of a tough one since colourblindness takes so many forms.  The overlap issue that the glasses can help out with by notching out the areas of visible spectrum that are doubled up isn't present in any of the -opia types of colourblindness where the sensitivity is severely attenuated or missing entirely.  For example, the glasses won't help much for someone with protanopia since red isn't partially overlapped with something else that can be separated out by notching out the overlap, the red's completely gone.

I have an issue with the terminology. Calling everyone with color vision deficiency "color blind" is flatly wrong. When I took the color test first time, the nurse flatly stated, "oh, you can't become an electrician now when you are color blind", even if the test showed I only had an issue with some red-green shades. I could even hear her snickering when I didn't see a number on one of the test pages that she could see! I have no issue separating red and green cables, or color of traffic lights, it's only closer shades of red and green I have an issue with. It's like even the professionals don't get it, that there are indefinite shades of colors and it's the majority's color vision that has defined where the boundaries go between different basic colors and shades. Someone with protanopia can correctly be called color blind, but if you have a lesser deficiency and can distinguish separate basic colors, it shouldn't be called "blindness". Clearly the tests are created so, that you can determine if the person is totally blind, or only has a certain degree of color deficiency. They should have made a numbered scale for it, just like for normal vision. I get that the scale can't be made accurate, but at least it would give an indication.

Why even get into the weeds over the catch-all terms when the various forms and severities are already in named categories, eg. protanomoly and protanopia?

For the record, I have protanopia and I have always described myself as colourblind.

Lastly, as the person who needed to start the thread has experienced, dealing with the problems it causes is the bigger issue, by far, than picking a name for it which is a secondary - and by secondary, I mean a distant number two - consideration well behind figuring out how to work around the surprises it throws up.
 
The following users thanked this post: nctnico

Offline SiliconWizard

  • Super Contributor
  • ***
  • Posts: 15797
  • Country: fr
Re: Am colour blind, need help identifying bands
« Reply #53 on: August 27, 2022, 06:31:03 pm »
Uh. AN eye doctor with no testing for color blindness? Really? They need to change eye doctors.
Not an eye doctor, just the generic doctor. But the generic doctor didn't see any need to forward to an eye doctor.

Not judging what they do or do not from afar without context, but anyone concerned with a vision problem should go see an eye doctor, if just to make sure. A generic doctor can do almost nothing serious about your eyes, except maybe treat a minor infection, and even so, an examination with proper equipment is often prefered to rule out any other more serious problem.

I'm a bit surprised, things are probably different depending on countries and habits, but over here, eye exams are done routinely on children, and are recommended once a year or couple years when adult. And any eye exam I got included not just acuity but also color blindness tests. So that's definitely something that shouldn't go unknown for a long time. Just my 2 cents, I don't know the context, so just saying in general.


 

Offline pcprogrammer

  • Super Contributor
  • ***
  • Posts: 4670
  • Country: nl
Re: Am colour blind, need help identifying bands
« Reply #54 on: August 27, 2022, 06:41:06 pm »
Uh. AN eye doctor with no testing for color blindness? Really? They need to change eye doctors.
Not an eye doctor, just the generic doctor. But the generic doctor didn't see any need to forward to an eye doctor.

Not judging what they do or do not from afar without context, but anyone concerned with a vision problem should go see an eye doctor, if just to make sure. A generic doctor can do almost nothing serious about your eyes, except maybe treat a minor infection, and even so, an examination with proper equipment is often prefered to rule out any other more serious problem.

I'm a bit surprised, things are probably different depending on countries and habits, but over here, eye exams are done routinely on children, and are recommended once a year or couple years when adult. And any eye exam I got included not just acuity but also color blindness tests. So that's definitely something that shouldn't go unknown for a long time. Just my 2 cents, I don't know the context, so just saying in general.

In the Netherlands it is more common to see an optician to have ones eyes checked. When done proper they also use the red/green tests next to the +/- deviation and other measurements needed on your eyes. Takes a burden of the real eye doctors.

From what I understood from here in France is that the opticians have less allowance in this respect and that when you need a new prescription you have to see an eye doctor for it.

Online wraper

  • Supporter
  • ****
  • Posts: 17952
  • Country: lv
Re: Am colour blind, need help identifying bands
« Reply #55 on: August 27, 2022, 06:55:51 pm »
Yes often we need lift a leg to get a sensible measurement however there are other ways, a very old one called the razor blade technique. These days we would instead use a scalpel or snap off blade knife to break a nearby trace, get the measurement and later apply a solder bridge over the cut.
Why would you do this? It's literally faster to desolder a terminal. And then solder it back rather that cutting, scraping solder mask, soldering a jumper wire. The only valid reasons to me would be if the part is hardly accessible on the top side or it is a high pin count device.
 

Offline SiliconWizard

  • Super Contributor
  • ***
  • Posts: 15797
  • Country: fr
Re: Am colour blind, need help identifying bands
« Reply #56 on: August 27, 2022, 07:00:24 pm »
I know that some countries have "optometrists" who can do a lot more than in others where opthalmologists are the only ones who prescribe.
Over here (and I'm sure that's the case in many other countries as well), "opticians" are basically like pharmacists but for vision correction products only. So they are only allowed to sell, adapt and give some advice, but not prescribe anything indeed. They can also make some minor eye exams such as acuity but just as a check since they can't prescribe.

Never going to an opthalmologist is an issue IMO. Some serious conditions could go undetected for a long time until it may be too late to take action, and opticians or optometrists may not be able to detect them.

 

Online nctnico

  • Super Contributor
  • ***
  • Posts: 28429
  • Country: nl
    • NCT Developments
Re: Am colour blind, need help identifying bands
« Reply #57 on: August 27, 2022, 07:02:56 pm »
Yes often we need lift a leg to get a sensible measurement however there are other ways, a very old one called the razor blade technique. These days we would instead use a scalpel or snap off blade knife to break a nearby trace, get the measurement and later apply a solder bridge over the cut.
Why would you do this? It's literally faster to desolder a terminal. And then solder it back rather that cutting, scraping solder mask, soldering a jumper wire. The only valid reasons to me would be if the part is hardly accessible on the top side or it is a high pin count device.
Agreed. Cutting a trace means you are physically damaging an otherwise good circuit board!
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline pcprogrammer

  • Super Contributor
  • ***
  • Posts: 4670
  • Country: nl
Re: Am colour blind, need help identifying bands
« Reply #58 on: August 27, 2022, 07:24:12 pm »
I know that some countries have "optometrists" who can do a lot more than in others where opthalmologists are the only ones who prescribe.
Over here (and I'm sure that's the case in many other countries as well), "opticians" are basically like pharmacists but for vision correction products only. So they are only allowed to sell, adapt and give some advice, but not prescribe anything indeed. They can also make some minor eye exams such as acuity but just as a check since they can't prescribe.

Never going to an opthalmologist is an issue IMO. Some serious conditions could go undetected for a long time until it may be too late to take action, and opticians or optometrists may not be able to detect them.

In the Netherlands the opticians have more qualifications and are trained to do a similar job as an eye doctor. They have a lot of the same equipment and test for all kinds of problems like eye pressure or cataract and will give advice to see a proper eye doctor when needed.

Offline pcprogrammer

  • Super Contributor
  • ***
  • Posts: 4670
  • Country: nl
Re: Am colour blind, need help identifying bands
« Reply #59 on: August 27, 2022, 07:28:17 pm »
Yes often we need lift a leg to get a sensible measurement however there are other ways, a very old one called the razor blade technique. These days we would instead use a scalpel or snap off blade knife to break a nearby trace, get the measurement and later apply a solder bridge over the cut.
Why would you do this? It's literally faster to desolder a terminal. And then solder it back rather that cutting, scraping solder mask, soldering a jumper wire. The only valid reasons to me would be if the part is hardly accessible on the top side or it is a high pin count device.
Agreed. Cutting a trace means you are physically damaging an otherwise good circuit board!

Another reason could be for SMD components, but more likely is that tautech is pulling our legs because he is pissed about the TEA thread.

See here: https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/msg4383775/#msg4383775

This is what he wrote on the new forum for TEA
Quote
Doing my best to plaster some poo in their laps and draw DJ into the discussion....we'll see.

Offline SiliconWizard

  • Super Contributor
  • ***
  • Posts: 15797
  • Country: fr
Re: Am colour blind, need help identifying bands
« Reply #60 on: August 27, 2022, 07:34:11 pm »
I know that some countries have "optometrists" who can do a lot more than in others where opthalmologists are the only ones who prescribe.
Over here (and I'm sure that's the case in many other countries as well), "opticians" are basically like pharmacists but for vision correction products only. So they are only allowed to sell, adapt and give some advice, but not prescribe anything indeed. They can also make some minor eye exams such as acuity but just as a check since they can't prescribe.

Never going to an opthalmologist is an issue IMO. Some serious conditions could go undetected for a long time until it may be too late to take action, and opticians or optometrists may not be able to detect them.

In the Netherlands the opticians have more qualifications and are trained to do a similar job as an eye doctor. They have a lot of the same equipment and test for all kinds of problems like eye pressure or cataract and will give advice to see a proper eye doctor when needed.

I see. But in this case and back to what nctnico said, the guy should probably have seen at least an optician and not just a GP, and I'm surprised the GP didn't suggest that. Oh well. :)
 

Online tautech

  • Super Contributor
  • ***
  • Posts: 29810
  • Country: nz
  • Taupaki Technologies Ltd. Siglent Distributor NZ.
    • Taupaki Technologies Ltd.
Re: Am colour blind, need help identifying bands
« Reply #61 on: August 27, 2022, 08:33:49 pm »
Yes often we need lift a leg to get a sensible measurement however there are other ways, a very old one called the razor blade technique. These days we would instead use a scalpel or snap off blade knife to break a nearby trace, get the measurement and later apply a solder bridge over the cut.
Why would you do this? It's literally faster to desolder a terminal. And then solder it back rather that cutting, scraping solder mask, soldering a jumper wire. The only valid reasons to me would be if the part is hardly accessible on the top side or it is a high pin count device.
Over the decades PCB layouts have evolved and still they present many faults, namely a lazy layout engineers consideration to possible rework in which there are risks of damaging the PCB.
Older PCB and especially TH layouts and often small thin annular rings subject to lifting and we've all done that haven't we ?
It's a case by case decision to know when to get the scalpel out.
Avid Rabid Hobbyist.
Some stuff seen @ Siglent HQ cannot be shared.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf