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Nagler type 4 and 6?

Started by Grumpy_one, 09/08/2003 07:23PM
Posted 09/08/2003 07:23PM Opening Post
Why is there a 75.00 price difference between the 11 and 13 type 4's, and 12mm type 6? What is the basic diffenece between these ep's? Thanks
Posted 09/08/2003 07:48PM #1
The type 4 is MUCH bigger with larger glass. The 12mm Type4 is a lot more EP than a 13mm type6. I have owned both and sold the 13mm Type6 and kept the 12mm Type4.
Floyd

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Posted 09/08/2003 10:17PM #2
The 12mm Type 4 (the oldest Type 4) is a 6-element eyepiece with plenty of eye relief. The 11mm and 13mm Type 6's are newer in design, have 7 elements, and sport 12mm of eye relief. The eye relief difference is one reason why the sizes are so different. Another seems to have something to do with the Type 6's employing more high-index "exotic" glass types. The price difference reflects the different costs in making these eyepieces, and the type 6 and type 4 designs are apparently very different--no reason to expect their costs to be similar just because their focal lengths are.
--
Mike