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Swift 8.5x44 ED

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#1 moynihan

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Posted 01 December 2003 - 12:58 PM

:question:

#2 Guest_**DONOTDELETE**_*

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Posted 01 December 2003 - 03:48 PM

Moynihan, what is your question? I had a chance to get some of these back in Sept. and missed it. There is a discussion about it though at the time.

#3 Guest_**DONOTDELETE**_*

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Posted 02 December 2003 - 12:00 AM

I have a pair of the previous generation model. Optically and mechanically they are a joy, and for birders (which I am not) the ED model may be worth the extra expense, but I question its utility for astro use (especially at 8.5x)

I use mine for daylight observing. For astronomy, I prefer at least 50mm objectives, and find 10 power provides the best FOV vs. penetration, for my eyes.

#4 moynihan

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Posted 02 December 2003 - 08:52 AM

Whoooops! my typing did not stick in the message.
I was wondering about the qualitative differences, contrast etc. Between the ED and none ED versions of the Swift 8.5x44 Audubons?

jay

#5 KennyJ

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Posted 02 December 2003 - 01:12 PM

I'm not fully convinced that the undoubted advantages to be gained from using ED glass ( which is a difficult quality to quantify at best incidentallly )would be sufficiently apparant to behold on a 8.5 power binocular to warrant the considerable difference in price.

With spotting scopes for example the upgrade to what is defined variously as ED /HD / or even APO seems to come into it's own at the higher available magnifications.

For hand -held astronomy I maintain that 8.5 x 44 is very significantly easier to hold steady than 10 x 50 and I am speaking as one who actually owns and uses the Swift 10 x 50 Kestrel Audubons on a regular basis , having used the 8.5 x 44s in the past.

Everyone is different , but I think the 10 x 50s are VERY GOOD for daylight terrestrial use whilst only GOOD for astro -use.

Of course what I define as "good" will probably come across as quite meaningless without a detailed summary of epic proportions , but it is a quite carefully measured statement.

I must concede though that the well -documented field curviture and softness at the edges IS more noticeable with the lower power versions , so if tripod mounted the 10 x 50s would be the better choice for more reason than one.

Just my opinion of course -- Kenny.


#6 brocknroller

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Posted 02 December 2003 - 05:05 PM

I had a Swift 8.5X44 Audubon (regular version 820) and a Celestron 9.5X44 ED. The difference in color fidelity on-axis between the two was negligable, and the Audubons were noticeably sharper. Off axis, you could see some false color in the Audubons, but not much except under extreme contrast conditions (black crow against white snow) or if you looked at a bird off-axis. But who looks at birds off axis except Stephen Ingraham at BVD? As Kenny mentioned, the low dispersion glass makes more of a difference at higher magnifications and larger apertures. My club's Stellarvue 85 APO flourite refractor (f 8.8 -- 750 mm FL) shows virtually no false color on bright stars or the planets even at 200X. More important, the flourite glass makes the colors converge at the same point, which significantly improves the sharpness of the image. But the color divergance is so slight in a small aperture 8X binocular that unless the optics are poorly made you probably won't notice the difference except under extreme contrast or if you purposely move a bright object off-axis. The color correction in the new model Swift Audubon (820) is very good. So the gain isn't worth the extra money, IMO. The exception would be if you are particularly sensitive to false color. Some people naturally are, and others have trained themselves to find it by testing too many binoculars! Brock

#7 brocknroller

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Posted 15 December 2003 - 12:12 AM

Another opinion...

Here Barry Simon compares the Audubon ED to the Eagle Raptor (basically the same optics as the non-ED Audubon).

http://groups.yahoo....et/message/2868

If you don't want to join Yahoo groups, email me and I'll send you a copy of the review.

Btw, Digital Photo and B & H Camera sell the EDs for $339, so that's only about $70 more than the non-ED version.

Brock




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