New Digital FF measurments?

[PhillyEyes]

So im sure you are all aware of the benefits of Digital Free-Form PAL's. These manufacturers say for best results to measure the vertex distance, panoramic angle, and on some, even the degree of panto tilt. My question is this, what methods do you use for the measuring of these extra features? If you do at all.

To be honest I take the height and only recently I started to measure vertex distance with a pd ruler . I do not measure panoramic angle, nor the panto tilt. I just assume the lens is designed with all these factors to be averaged out.

SO, do you guys think the extra measurements are not really required, the lens will still out-perform generic PAL's? To fine tune the lens, if I wanted to take all these measurements, is there one method better than another for taking panoramic angle? panto? and am I measuring the vertex distance correctly the old fashioned way with a pd mm ruler?

Any advice/methods of measurment would be greatly appreciated :)

[Judy Canty]

If you want to optimize the benefits of the lens design, the measurements are necessary. If you don't, they're not. You can spend thousands on an electronic device or you can use a distometer. Both Zeiss and Shamir offer free tools that will do the job as well. Talk to your lab or your lab rep.

[acoakley]

I do take all of the measurements...if the patient is paying for a digital FF PAL, I want them to get the best performance out of it that they can. I use the free tool from Shamir to take the measurements.

[PhillyEyes]

Thanks for the reply, what tool from Shamir are you referring too?

[acoakley]

We received a kit from our Shamir rep that has a Panorameter which can be used to measure pantoscopic tilt and face-form angle. The kit also includes what is essentially a PD ruler to measure Vertex distance. Our rep did a brief training on free form and then sent us the kit after we completed the brief training.

[Barry Santini]

Keep in mond that Shamir Panorameter face form measurements factor the wearer's PD into their "effective" tilt calculation. To avoid confusion with the more standard "frame" wrap measurements, sharmir's Panoramtere's scale adds a value of 90 to the calculation.

Example:

Standard frame wrap measurement (no PD included) (via protractor) = 20 degrees

Shamir's Panorameter, set to the actual frame PD (for instance, 76) = 120 degrees

Using a client PD of, say 62mm, the Panorameter may read = 103 degrees (which is to say, the "effective" wrap angle of that frame at a 62 PD is equal to "13" degrees (103 minus 90).

Hope this helps. Panorameter values should ALWAYS be entered as read, i.e. 90+ degrees. This will distinguish these PD-integrated wrap values from the more conventional protractor-derived wrap values that pertain to the frame alone.

B

[Opticianjw]

I use the Optikam for taking digital measurements. I purchased my first system 4 years ago before the product had the capability to take digital measurements, it was just a frame and lens selector. When I started selling digital lenses and realized the true benefit of digital technology, I started researching products that would enable me to take the additional measurements. Without taking those additional measurements, the patient would not be getting the true value of digital lenses. After looking at all the options and associated cost, I purchased the Optikam with digital centration. Not only was it the most accurate system available, it was also the most economical. In fact, I purchased my system with using my co-op dollars I accrued from my lab and frame manufacturers, plus I get a 4,750.00 tax credit last year. Using the Optikam justifies the additional cost to the patient and it impresses them when that I have it. They can see that I provide the latest and most advanced technology available and I like staying ahead of the curve, I would strongly recommend it. Feel free to call me at my office,if you any questions 732-350-1900, Joel

[lou_riccio]

Really I think it would depemnd on the lens you are dealing with. Some the additional meassurements make a significant difference. Whereas with others the options during manufacturing are more limited so the additional meassurements are either not needed or do not make a significant difference.

[Iroc]

I agree. I think taking those extra measurements on someone with a light Rx doesn't change the lens configuration nor the "as worn" Rx hardly if any. I do take those extra measurements with higher Rx's or more complex ones. Zeiss equipped us with their measuring tools but for the vertex, I prefer the the good ole distometer. What kind of FF lenses are you using?

[PhillyEyes]

I called my Shamir rep tuesday, Wednesday he came in with the kit for taking these extra measurments. I am now freeform "certified". Im going out tonight to celebrate this ultra high-end certification


Thanks Barry Santini for the reference as to using this tool, it is helpful

[Nikolay Angelov]

We are using Rodenstock's ImpressionIST since around 2008.
It is a 3D video-centration system using 2 cameras.

Complete measurement and analysis of the images is done in around 3 minutes. You get:

1. mono fitting height,
2. mono centration distance (horizontal)
3. boxing sizes of frame
4. frame wrap (Face Form Angle)
5. monocular pantoscopic tilt
6. corneal vertex distance (CVD)
7. optimal blank diameter

Every client/order is measured (multifocals, SV etc.)
The only exceptions that don't go through the ImpressionIST are very small RXs (due to time constrains). But this is temporarily, we will do them all in the future .

With PALs, measuring individual parameters is useful (even when the they aren't used for optimisation).
The measurements help us fit the PAL (when possible) to the standard/fixed position of wear it was designed for (Pantocsopic angle, FFA, CVD etc.). That way we get the best vision possible from the lens.
In general we are very happy with the results from the additional measurements .

PS: The accurate measurements exposed some fitting errors we made, so we improved our fitting technique as well.

Best regards,
Nikolay Angelov