While doing a quick runaround looking for PD information, I tripped over optiboard.
This interesting exchange between a number of optical professionals reaffirms my thought that this Pupillary Distance (PD) measurement thing is more "art" than science.
"Pupilometers are not as acurate (sic) for me either."
"Just because I use a pupilometer that doesn't mean that I can't use a ruler."
Even "dotting the pupil" on the lenses like LensCrafters did to me every time.
"I use the pupilometer to measure adults, but I still dot the pupil. Then I have something to compare. I am usually within .5 mm each eye."
Here's the link:
Note to Sara, "reply me on this."
- At June 12, 2008 at 3:11 PM Marko said...
I get a different PD from different places, and even going back several times to the same place I get slightly different PDs, all using the PD omiter or whatever the device you look into is called. First, it was different on each side, then it was the same, then after trying again really hard, they are both the same and larger. I have ranged from 63 to 65, and like I said, sometimes my monocular PDs have been different, some times the same. I asked them to check my near PD, and they sometimes say "we don't do that" to ok, and I got a 59, which is unusually lower than my distance.
For most people, a couple mm won't matter, but if you are like me and have progressives, it can make a big difference, or if you have prism.
I am finally happy with the 3rd measurement I got from Costco (65/59), because we tried it a bunch of times and two different people taking it. Another time though, two different machines gave slightly different readings. The 65 mostly matches my own eye-dot experiments and my wife reading me using various tecniques we got of the net.
Going to an optician and paying more might be worth it if more of them knew what they were doing. It seems tough to get someone that is not an idiot, or can't be bothered to get it right for the special cases. Costco so far has been good to me, mostly. I can return the glasses whenever I want if they don't work. Online, I have had several glasses not work right and I hate being bothered to mail things back.
- At July 6, 2008 at 1:14 AM Anonymous said...
Near pd is always 3mm less than distance pd. Exception for "hypertelorism" - it is then possibly 4mm less. I'm sure all you semi-educated net nerds will enjoy googling the "above".
Variations with pupillometers means that one or both units were resting off-centre when placed on the bridge of your nose. If you have previously fractured your nasal septum, or if you look like Shrek, then expect problems.
So Shrek, request that your frames are "dotted up" for accuracy. This removes any discrepancy between the mounting position of the chosen frame, and that of the p'ometer. Or get a nose job. Try www.eightdollarfacialreconstruction.tightarse.netnerd.you.
You CANNOT have a 65/59 pd. Goes to show how we have to deal with know-all clients, who waste our time and contribute to overheads that drive up our cost structure.
If you want to bitch re price, ask the shopping centre owners why they charge $120k for the shop site. Gross margins of 600% dwarf the final margin of 8-15% after all costs.
If anyone chooses to counter with comment such as accommodative esotropia / convergence excess could (although unlikely) account for a 65/59 pd, sadly this is my first and last "blog". I found this site by accident, and don't feel the need to return to it to be enlightened by half- or quarterwits whose little bit of knowledge is worse than having none at all.
Trust who shall all feel witty rebutting my blurb, and feel very important doing so.
I however, will be talking to REAL people. I pity myself for wasting the last few mins on this.
- At July 10, 2008 at 10:32 PM Anonymous said...
Wow, these guys are really scared. One almost feels bad for them. Not quite, but almost.
Anonymous and his colleagues would be better served by alleviating the sort of problems Marko encountered and thereby perhaps creating the perception that they provide a service worth their prices.
I pity the "real people" who have to deal with his sanctimony in person.