Thanks Graeme . . If using Outlook Express, the secret is to be careful as to which button you press: * REPLY goes to the group on this list
* REPLY ALL goes to both the group and to the originator (as a private email, thus they (only) get two copies) Be careful that your FROM address is the correct one as this list only accepts that which you registered . . . . and if you have another one set as DEFAULT it will bounce (not an issue if you only have one email address). To send a private email, use REPLY ALL then delete the aus-soaring entry so that the private one remains alone. When using normal NEWSGROUPS (like recreation.aviation.soaring) the REPLY ALL button is the correct one to use. Note that often people use a bogus email address in newsgroups - usually you can see the change required to send them a private email (eg I use [EMAIL PROTECTED]). This stops the automated SPA M harvesters. Now I hope that I have been able to help you!!! Cheers, Jim Kelly. ----- Original Message ----- From: "Graeme Thompson" <[EMAIL PROTECTED]> To: "Jim Kelly" <[EMAIL PROTECTED]>; "Discussion of issues relating to Soaring in Australia." <[EMAIL PROTECTED]> Sent: Sunday, October 10, 2004 9:21 PM Subject: Re: [Aus-soaring] re: Best sunglasses for gliding? Hi Jim, Short answer, yes, this is the physics of lens optics, but this can be minimised with appropriate lens design and correct dispensing ie placement of the lines relative to your primary gaze. Some bifocals can be made with zero jump but these have the segment right across the lens which would then interfere with the peripheral vision below the horizontal. I don't know whether this reply will go to everyone, if so, it would probably be better not to clog up the group with technical or professional queries, but I would be more than happy to reply to private emails if I can be of assistance. Graeme > Graeme, I am interested to know if it is necessary for the > image > to 'jump' as it is presented to the eye form one bi/tri region > to > the next? EG when driving with mine and glancing at the > speedometer (which I can read adequately from either lens - but > the line seems to fall naturally though the middle . . ) I have > to look in 'two different places' as my head moves just a bit. > Is > this a fact of physics or does the lens maker have control over > this sort of thing? > > Thanks again. > > Cheers, > > Jim Kelly > > > > > > > ----- Original Message ----- > From: "Graeme Thompson" <[EMAIL PROTECTED]> > To: "Jim Kelly" <[EMAIL PROTECTED]>; "Discussion of > issues relating to Soaring in Australia." > <[EMAIL PROTECTED]> > Cc: "Discussion of issues relating to Soaring in Australia." > <[EMAIL PROTECTED]> > Sent: Wednesday, October 06, 2004 10:50 PM > Subject: Re: [Aus-soaring] re: Best sunglasses for gliding? > > > Thanks for the welcome Jim. > > I practice in Sydney and fly at Narromine. You are on the right > track when > you measured your map & instrument distances. Most refraction > (eye testing) > is done with the premise that reading is done at 40cm. so the > additional > power in the lower section of a multifocal is calculated using > that distance > and the residual focussing ability (accommodation) of the > individual's > eyes, which decreases with advancing maturity. This is fine for > most > activities but there are some which don't fit the pattern, > particularly some > sports and some unusual occupations. Unless your optometrist is > made aware > of your special needs, you will be unhappy with your new specs. > > As well as the critical distances you mentioned, the angle of > your head > relative to the instruments is important. While nothing is as > good as having > your optometrist measuring everything while you are strapped > into > the > cockpit, a side on photograph will give him (or her) an idea of > what you > need, how to place the optical centres, and the type of lens > which would > work for you. Incidentally, the term multifocal means any lens > with more > than one focal distance, although it is loosely applied > specifically to > progressive power lenses. > >>From a personal perspective, I find that lower tech trifocals > work well for > me, allowing clear distance, intermediate and close vision > without any > distortion, but some people will find that the simple bifocal > will cover all > their needs, particularly if they are under 50. > > If you "must have" a specific tint in your glasses, just like > Joe Blow's, > try and separate them from Joe long enough to let your > optometrist put them > in his spectral analyser, if he has one, so that a reasonable > match can be > obtained. They are not 100% accurate but a darn sight more > objective than > holding the lens over a bit of white paper. > > I know that there are other optometrist pilots out there and > these are the > professionals who will be attuned to your needs as they will > have > had to > solve the problems for themselves. > > Good luck in your search! > > Graeme > > > > ----- Original Message ----- > From: "Jim Kelly" <[EMAIL PROTECTED]> > To: "Discussion of issues relating to Soaring in Australia." > <[EMAIL PROTECTED]> > Sent: Wednesday, October 06, 2004 12:14 AM > Subject: Re: [Aus-soaring] re: Best sunglasses for gliding? > > >> Thanks very much Graeme, >> >> I suspect that you are just one of many lurkers out there!! >> >> Thanks for your professional comments. >> Perhaps you could also be so kind as to point us in the >> direction of what questions to ask our optometrist when we >> next >> visit so that we get the best script possible for safety and >> success?!! EG I've thought to measure the distance from my >> eyes >> to the panel, and to a map. >> Is there a clever way to define the position of the >> bi/trifocal >> edges >> from our weird prone seating position?? Etc. >> IE How can WE help YOU to get it right?? >> >> And why not tell us which suburb/city you service? You might >> get >> an offline email for exact details - it is in all of our >> interests to >> improve the safety of our sport and an optometrist that knows >> our issues has to be an asset! >> >> Any other professionals lurking out there - please join in - >> let's get the facts on the table and wrap up this thread with >> some good advice/conclusions and get up there flying again >> (with new sunglasses of course) ;-). >> >> Cheers, >> >> Jim Kelly >> Melbourne. >> >> >> >> >> >> > > > _______________________________________________ > Aus-soaring mailing list > [EMAIL PROTECTED] > To check or change subscription details, visit: > http://lists.internode.on.net/mailman/listinfo/aus-soaring _______________________________________________ Aus-soaring mailing list [EMAIL PROTECTED] To check or change subscription details, visit: http://lists.internode.on.net/mailman/listinfo/aus-soaring