[ronh]

DocSarvis,
Thanks for the loupe lore. The nice thing about my B&L is that it comes with various graticles that enable measurement. Usually, that's what I use mine for. But, an ED triplet loupe, wow! I'd like to try a high classed model.
Ron

[brocknroller]

Originally Posted by FrankD

Hmm, I wonder. Would it be possible to send in some lens elements to be coated? I am thinking some of my older single coated porro models.

I do realize that the coatings are supposed to be matched to the lenses but it might still prove interesting depending on the cost.

Frank,

According to Professor Edz from Cloudy Nights, it can't be done for the very reasons you state above.

It's surprising because the coatings only add thousandths of an inch to the surface, but according to the "The Big Professor" (anybody remember Sandy Becker?), it's enough to make a difference.

But what would that difference be? Do you get a blurry image? More CA? Never asked him what happens if they stripped the old coatings and added new ones, but perhaps Henry or someone else will chime in here and tell us why we porromaniacs can't simply send our old porros in for upgraded coatings.

Granted, it might be costly, because right now it's a custom service and they'd have to either make their own coatings or lease the rights to use somebody else's, but heck, could it more costly than buying a $2K alpha? I doubt that.

They might have to re-polish the lenses a bit to make the curve compatible with the coatings. Seems doable, and it's not like they are starting from scratch and forming and grinding the lenses and making an entire bin.

I'd pay $200-$400 to upgrade some old porros with newer coatings, which are otherwise as good as anything out there today.

The problem would be where do they get the AR coatings? Every company has their proprietary blend. They'd have to license the rights to use those coatings, and that might be tough as well as costly. Or they'd have to make their own, and the market to upgrade coatings for the two of us and perhaps a dozen or so others won't make it cost effective unless Simon gets all his old porros updated, which will keep them in business for perpetuity :-)

Speaking of old classics, did you get my PM about the 7x50s?

Norton Nork

[FrankD]

Brock,

No, I didn't. Did you send it recently?

[DocSarvis]

Ron,
I was thinking only of the sort of loupe one would find around the neck of a botanist, entomologist or rock hound or in the case of the Swiss-Axe or the Schneider L1 in the hands of a jeweler or diamond merchant. For work I have used a B&L Hastings Triplet 7X illuminated model with a plastic handle that has a clear plastic skirt and interchangeable scales for measurments. I'm presuming that is the type to which you refer? I have one currently lost somewhere in the bowels of my office for which you have now prompted me to go exploring! Never say this forum doesn't cause positive action!

Best, Roger

[ronh]

DocSarvis,
Yep, that's it exactly, handy little buggers. Hope you find yours. Brilliant it may not be, but come on that is one seriously flat field.

Ah-HEM! Back on track you know. I say, does that Swiss Axe Triplet Hawk have "repellent coatings"?!
Ron

[DocSarvis]

Ron,
The Swiss Axe has SUPERB anti-reflection coatings! I don't know that they need repel rain, tree sap or dust. Since it also comes with a serious case of sticker shock I confess to seldom taking it into the field. I usually use the combination of the Belomo 10X on the Amateur Geologist lanyard and the B&L Hastings Triplet 20X on a fly fisherman's pin-on roller retractor as used by Ed Ricketts (Doc of Steinbeck's "Cannery Row").

A great source for various lanyards is Cabela's. Besides the roller retractors in the fly fishing section look in the hunting dog area for training whistle lanyards. Also where the duck and goose calls are sold so will be lanyards for them as well. I have an excellent double lanyard made to hold two whistles that is soft on the neck and is great for the 7X/14X B&L Hastings Triplet combo. Sadly, Belomos won't fit on conventional lanyards. Visit Amateur Geologist online for a source for Belomo lanyards. While at Cabela's, pick up a pack each of suitably sized stainless steel split rings and ball-bearing swivels. Those will make attachment and use much easier and a pack will last you almost forever if you don't fish.

As you might suspect, I have a rather largish collection of loupes and other magnifying devices (besides binoculars) going back to my first 5X "linen tester" folding magnifier I used when I was a kid starting a stamp collection.

Roger

[jgraider]

You can take the manufacturers light transmission numbers and throw them out the window. There's no telling how they compute their own, and no standardization of such. Marketing hype only.

[absolut_beethoven]

Originally Posted by ronh

Ludwig,
I am jealous to the max. My otherwise prized 7x Hastings Triplet, made by Bausch and Lomb, is, most embarrassingly, uncoated. I have often wondered what the extra 7-8% of throughput and concurrent reduction in veiling glare, which a top notch multicoating would give, would do for the view. Oh well, it works fine on the occasional exit pupil, an extremely high contrast object (or ought to be), and the odd little thing I need to measure to +/-0.02 mm. I guess I am not too picky, as I still enjoy a Leica Trinovid. Still I am in awe that you had your loupe coated. In a mild optical way I am reminded of Lou Reed's lyric, "Take a walk on the wild side." Rock on!
Ron

Just for you Ron, and all the other optics nuts out there, here are the pics of my 7x B&L Hastings triplet loupe with AR coating from the iCoat company. The B&L is the largest loupe on the right.

http://icoatcompany.com/Stainless.aspx

My 10x Zeiss doublet diamond loupe is in the middle and a specialty 10x Swiss made watchmakers 10x loupe is on the left. This triplet loupe consists of a cemented doublet with a small space between it and the third lens. The latter uses the old magnesium fluoride coatings (just like my Zeiss 3x mono), hence it has the worst effect on changing the color of the white background paper to a brownish yellow, but its distortion correction is outstanding.

The Zeiss has the least affect on its whiteness, followed closely by the iCoated B&L.

Please note that I tried using PS to correct the color of the very white paper that the lenses are sitting on to make it appear perfectly white, just as it appears in reality, but that washed out the colors of both the coatings and their effects.

See pics below taken from two slightly different perspectives.

[ronh]

Why, thank you for these photos. I can understand that for judging diamonds, clarity is everything, and the Zeiss doublet wins. For measurement with a graticle, field correction would win, and B&L does alright there. Colored reflections, you weren't making it up, oh joy in the land of the loupey!

To bring this digression back on track, just add water.
Ron