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ED glass usage in PORROS (1 Viewer)

cappi

Member
Aside from the Swift 804, 820 etc. series of bins are there other manufacturers using the ED glass in there PORRO binoculars ?
 
I am not aware of any current production fitting that, other than the Swift you mention.
There may be an individual focus model or two for the astronomy market . I also am not up on the specs for the giant 100mm to 150mm astronomy binoculars.
I have never seen one for sale used, but years ago, Celestron made a handheld porro that was "ED", i think it was 9.5x44 or so. I do not think it had very close focus.

I have the SwiftAudubon 8.5x44 ED. Have had it 8-10 years. I consider it truly apochromatic. Zero CA under any lighting conditions, across its field.
 
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Promaster has a Porro binoculars that has ad copy saying it. has ED glass. I am not certain about it Sometimes some of these new companies make a good description for the roof model and then they repeat it for other models they also sell.

They want 400 dollars. It is pricey. It is a hard swallow to pay for a trial.

ebay auction Promaster-Infinity-EL-M-8-5x43-Binoculars

That kind of mix-up is the case here. Check out these two lines from the description from the ad you referenced above.

Type of Prism: BAK4 Porro Prism
Coating: Silver and phase coated

Huh?

I think the Swift 820 Audubon ED may be the last of its kind.

What's odd is that they are not even listed on Promaster's Website:

http://www.promaster.com/products.asp?CatID=60&SubCatID=1

Brock
 
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The Promaster Porro is the real deal apparrently. I asked Doug at Camera Land and he informs me they are available at $279.00 US.
 
Here is one (big one):

http://www.deltaoptical.net/eng/sto...tanium/lornetka_delta_optical_titanium_8x56ed

Haven't tried it, but allbinos have. http://www.allbinos.com/199-binoculars_review-Delta_Optical_Titanium_8x56_ED.html

Seems like it's optically good, but the build quality is only fair.

I like the FoV!

Odd that out of all the models, they added the ED glass to the 8x56, which already had low CA. Or should I say 8.8x56?

So you get a larger FOV (7.4*), but you pay for that with truncated exit pupils that cut down the light, plus a smaller than specked exit pupil (6.3mm vs. 7mm), so you're carrying around a 56mm objective bin that gives you around the light gathering of a full sized model (42-45mm?), they didn't specify the level of cutoff, but said the ED model had more truncated exit pupils than the non-ED one they reviewed.

All this makes no never mind to me since I can't use a 7mm exit pupil anyway, but I'd be happier with a more compact, lighter weight 7.4* 8x42 ED model with round exit pupils and better mechanics.

A close focus of 9.8 ft is good for this size porro; the 8x32 SE has the same close focus distance. The light transmission graph is also very good. It looks similar to the graph of the 8x32 SE, but the ED is better in the mid range.

So it has potential, but I'm going to wait for some improvements before putting it on my Wish List.

Nice find, vop.

Brock
 
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Brock,

Just out of curiousity, why do you think they won't have ED glass at that price point? We have seen a number of ED glass roofs at that price point and slightly below...Bushnell Legend Ultra, Pro Optic, Zhumell, etc.... I have always heard that it is less expensive to make a porro than a roof so wouldn't it make sense that someone, like Promaster, could come up with a relatively inexpensive porro with ED glass?

...and don't go waiting for me to buy one. My interest in anything above 8x is practically non-existant. If it was an 8x42 with a 400+ foot field of view or a 7x35/42 then I would have already bought it. I have no interest currently in 8.5, 9 or 10x binoculars.
 
Looks like Brock guesed his way into this one. ;) According to Doug at CameralandNY, he can find no indication these Promaster porros have ED glass.
 
I will let one of the others get all technical. My experience is that, yes, porro prism binoculars, general, do tend to display less CA than their roof prism counterparts.
 
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