Hi Brock,
I don't recall saying there would be more CA, since CA is an aberration that results from the optical design. I may have speculated, however, that
awareness of color fringing may increase with improved coatings, simply because fewer frequencies are selectively reflected (i.e., filtered) at the various glass surfaces. That, in turn, might lead the average observer to be more annoyed with of the effects of the aberration and to justify the use of ED glass in new designs, — so as to actually reduce CA. If that's what you meant, I plead guilty.
It's an optical variant of "no good deed goes unpunished."
Ed
Hi Ed,
Here's what you wrote:
"Improved transmission, given identical optical designs, i.e., lens curvatures, spacings, and glass properties, should make fringing more apparent. As transmission approaches 100% the distribution must flatten out and colors reveal themselves to their full extent."
I understand the clarification you made in your reply, however, the final result is the same - users see more color fringing in newer bins, which garners complaints, which in turn causes manufactures to add ED glass to their new bins, which greatly increases costs (except in ChinBin ED clones), whereas the older models with lesser coatings didn't need low dispersion glass, because the CA was tolerable.
The case I mentioned exemplifies your point, the 501 lead glass SE had low CA, but also less vivid colors across the board whereas the 505 lead free glass SE has more vivid colors, but also more vivid CA.
You can bench test the two to see if there really is more spurious color at 64x, but even if there wasn't, that doesn't change the fact that I see more at the EP in the newer model at normal power.
So now I want Nikon to add ED glass to the next gen of the SE series (if there ever is one) to reduce the color fringing. And if they do, I'm going to pay for it through the proboscis.
The CA in the 505 is not horrible by any means, but it takes less high contrast to bring it out, and it starts closer to the center than my older 501s.
In the 501s, I was rarely aware of color fringing except in the winter, such as looking at a crow against snow. But with the 505s, it's more noticeable even in the warmer months.
So it seems there's a price to pay for those more vivid colors, which is more vivid CA!
However, in individual cases, I still think the lead free glass itself might have been the culprit or at least partly to blame such as the full sized LX Ls. Some expert measured the light transmission between the LX and LX L (I had it bookmarked, but that died with my old computer), and I'm fairly certain the light transmission was the same or very close between the two models
even though the image looks brighter through the LX L.
So that leaves coatings and glass, and if the transmission is the same, that eliminates coatings.
When I look through the LX L, it has a warmer bias like the lead free glass EII. Reds are a bit organey, blues a bit purplish, yellows are eyegasmic day-glo. Very bright lit objects can overwhelm the contrast and detail on the LX L.
The overall effect with the LX L is brighter
looking images, but with colors that are not quite true to life, and also increased CA (the Venturer LX already had more CA than some people could tolerate).
So my theory was that Nikon didn't get it right the first time around with their lead free glass just as OHARA didn't get it right their first time around with lead free glass.
Others on the "Why Lead and Arsenic Are A Good Thing" thread made the similar comments about lead glass vs. lead free glass in the updated model of the same bin.
For some reason, this frazzled some people, not only you, but also Ron H, who had unfathomable faith in "science" to the point where he believed that a manufacturer wouldn't put out a glass that was inferior to its previous model.
That's "faith" all right, but it ain't in science! There are economic pressures at work here that puts the "science" on the back burner (actually "technology", despite the myth, science doesn't always precede technology).
Competition causes companies to "rush to market" sometimes before a product is read for "prime time". The first gen EDG is a good example. Early pre-production models were reviewed by experts who complained about the cap coming loose, but Nikon went ahead and produced the first run with defective caps anyway.
Why? That's anybody's guess. Here's mine. Whether it was corporate espionage or an "accidentally on purpose" information leak (like that Valerie Plame's name by Scooter Libby, aka "The Fall Guy"), somehow Nikon got wind of the SV EL, which has many of the same features as the EDG.
Not to loose its "edge," Nikon rushed the EDG to market while they worked on an aftermarket solution to the loose cap problem.
As it turned out, Swaro delayed production of the SV EL so there was no need to rush the EDG to market. So now the original Nikon EDGs are selling for $1,300 on the refurb market, which has got to sting Nikon.
They shot themselves in the foot with this one. I know I'm speculating, but Nikon is not stupid, if they rushed to market, there was a good reason for it, and it may well have been to beat Swaro.
I'm not sure what Nikon did differently to the EDG than it did with the LX L, besides adding pincushion to eliminate the extreme "rolling ball" on the full sized LX/LX Ls, but the colors are more true to life in the EDG than the LX L. More like the Venturer LX. In fact, I compared the 8x32 LX to the EDG and the contrast, color saturation, and color rendition were very similar, but with less CA in the EDG.
So it was a case of two steps forward and one step back with the LX L.
The EDG is the bin that the "Premier LX L" should have been had Nikon taken its time to make a full redesign, but again, with Leica, Zeiss, and Swaro coming out with new models, and comments that the Venturer LX was too heavy and not as bright as the competition, Nikon need "something" to market on short notice.
Lots of less picky people than I like the LX L, so it wasn't for naught, but the LX L also wasn't all that it could have been, had Nikon "reinvented the wheel" instead of merely putting softer rubber on it.
The irony is now that lead glass
can be made with the same properties as lead glass, people are expecting ED glass.
I recall comments on the Monarch X about the price they're asking "and it doesn't even have ED glass".
Now that good quality ED glass bins can be purchased for under $300, there's no going back.
Low dispersion glass, whether it's called ED or by some other proprietary name, is going to be considered "standard equipment" for here on in on quality binoculars.
And it's all your fault, Ed, for asking for higher light transmission optics. "-)