I will be only using this for hunting.What does the HD upgrade get me for an extra $300.00?

An HD lens coating has different meanings depending on the manufacturer of the optics.

Every manufactuer I have looked at online states it has a Flourite coating or is impregnated with it.So basically they are the same.What I need to know is what does it do for me a hunter,not a birder or photographer???

I have a Swaro AT80HD that i use for spotting bullet holes at the range. I honestly don't think the HD is justified in my case. A bird watcher might think otherwise, though.

Thanks for the replies.I spoke with a Leupold Tech
who told HD would give me no advantage for hunting.So I ordered the non HD model.

quote:

Originally posted by OLBIKER:
Every manufactuer I have looked at online states it has a Flourite coating or is impregnated with it.So basically they are the same.

Well, if you are talking about something like the Bushnell Legend Ultra HD then it means "RainGuard HD is a patented, permanent, hydrophobic, oleophobic lens coating that causes moisture from rain, snow, sleet and your breath to instantly bead-up into smaller droplets and scatter."

If you look at Leupold, they describe their HD optics as "High Definition" but make no mention of Fluorite. Instead they say it "employs an Extra Low Dispersion Optical System to maximize color fidelity and contrast".

Vortex says, "Premium HD (High Density) extra-low dispersion glass delivers the ultimate in resolution and color fidelity, resulting in High Definition images." Again, they do not mention Fluorite. They do not describe their best coatings as HD but as XRPlus, "XRPlus premium fully multi-coated lenses deliver the highest level of light transmission for maximum brightness."

Zeiss explains their definitions in the FAQ. HD does not mean it has Fluorite coating. HD means High Definition, "High Definition. HD is not a type of lens. Instead it describes the result of the ED lenses: very good resolution" and the ED lenses are "ED Extra low Dispersion = low chromatic aberrations" and do not have Fluorite unless further specified. Instead, Zeiss uses FL to describe lenses with Fluorite coatings. "FL Binoculars or spotting scopes with glasses that contain fluoride (FL) for sharper, higher contrast images with significantly reduced chromatic aberrations; Fluoride Lenses; a special, high-quality sub-category of the ED lenses"

Leica spotting scopes are not named using HD or FL. But they all are described with this, "The FL glasses incorporated in Leica spotting scopes contain a lot of calcium fluoride. They ensure very low dispersion and better correction of aberrations – for an impressively natural viewing experience."

So, yes, it depends on the individual manufacturer's definition. Seeing HD does not necessarily mean it is Fluorite coated. Not seeing HD does not necessarily mean it is not Fluorite coated. You have to look at the individual specifications.

There is also a difference between Fluorite lenses and Fluorite coatings. Nikon describes the difference like this:

quote:

Fluorite lens
Fluorite is a monocrystal optical material that features a high transmission rate within both the infrared and ultraviolet zones. With its superb anomalous dispersion properties, fluorite intensely blocks the secondary spectrum in order to effectively correct chromatic aberration within the visible light spectrum – something that is more difficult to achieve at longer focal lengths. It is also significantly lighter than optical glass, giving you a more effective lens with less weight.

Fluorine coat
Nikon's fluorine coat effectively repels dust, water droplets, grease or dirt, ensuring easy removal even when they adhere to the lens surface. Thanks to Nikon's original technology, it delivers higher durability and is more peel-resistant. Compared to other manufacturers' coating of a similar kind, fluorine coat endures a higher frequency of lens surface wiping and provides longer-duration staying power. Its anti-reflective effect also contributes to the capture of clear images.

Flourite in glass is not a coating. It is a component enfused into the glass.
The only optic that might be used by a hunter that utilizes a "pure" flourite crystal lens is Kowa in the top end spotting scope. Most people contend that they have the best resolution of any "small" optic device.
The short coming is that crystal is soft and more easily damaged than a glass component. I not sure it is suggested that it is "banged around".
Literature I have read from Zeiss, Leica and Leupold on their HD spotting scopes contend they do use Flourite enfuse glass on their objective cluster.
I have a Kowa, Vortex Razor HD and Leupold HD. I use the Leupold far more than the others due to its size and the long eye relief.
It is just easier to use than the other two in contoured positions on the side of a hill.
I use the Vortex for limited astronomy and the Kowa for general terrestrial viewing.
The Vortex and Kowa have easier to use zoom features as the Leupold is stiff but probably better sealed against weather.
They are all good.
As I said I prefer the Leupold for hunting.

EZ

It is all meaningless now as I have placed my order.We can close this thread.

Well, someone else might learn something. I found the replies useful.