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Re: comparing diagonals

Started by fblue, 01/24/2005 10:19PM
Posted 01/24/2005 10:19PM Opening Post
Mark,
Consider also that the 2" diagonal has a larger mirror of which only the central portion is being used. This is the best part of the mirror as far as flatness and shape. Because of this a 2" diagonal can be a better unit. Of course the quality of the coatings and mirror as well as the precision of the construction and alignment will effect the view just as much. So a good 2" is the way to go.

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
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Posted 01/25/2005 09:18AM #1
I have a different take on diagonals.

1. It would seem to me that making the central section flat of a 1.25 incher is probably slightly easier than doing a 2 incher, but in either case, its probably not a big deal.

2. Diaelectric Diagonals: Roland Christen has discussed them on various forums. My understanding is that the main advantage of dielectric diagonals is not that they have that high reflectivity but rather that the coating is rugged and durable so that it stands up to cleaning and environomental effects without damage. Thus one can reasonably expect that a dielectric diagonal will still be performing like new in 30 years whereas a coated diagonal will have deteriorated significantly in that time period.

Myself, I have a variety of diagonals ranging from a plastic bodied but glass mirrored unit that came with a $50 WalMart Meade to 2 inch TV Everbright that came with my Pronto when I bought it used.

The Everbright definitely is noticeably better than the Meade unit, I think each step of the way one gains a bit but I am quite sure I wouldn't spend the $300 that the Everbright cost new.

But, now that I have it, its a keeper, something that I will always have so that I will never need to think about buying another 2 inch diagonal...

For that alone, it's worth the money.

jon