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Enhanced Uranus showing Polar Cap and possible Aurora

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Sidewalk test continued

Started by fblue, 10/16/2004 08:24PM
Posted 10/16/2004 08:24PM | Edited 10/16/2004 08:27PM Opening Post
Ok, so I thought it might be cool to do this test on other items in the box.
Take a look and see how the different EPs and other accessories fair.
I did a number of items that I thought might be of interest.
Note in the 2"-1.25" EPs you can see the step down to the 1.25" barrel in them (14mm UWA and 12mm T4).
The 31mm Nagler shows the field stop ring.
T-4 Naglers look the best on the test.
Paracorr and balow look very good to me.
Floyd

Attached Image:

fblue's attachment for post 19456

[SIZE="Large"][/SIZE][COLOR="Blue"][/COLOR] Floyd Blue grin
Amateur Imager
Posted 10/16/2004 09:02PM #1
I agree with Dan. Although, it clear what you photo is showing, uniform caps on the bottom would eliminate any chance that they are somehow influencing the image.

Paul Atkinson
Posted 10/16/2004 09:33PM #2
Very good! You will see that simpler optical elements show lower reflections due to less air-glass surfaces and the fact that most of them use low index materials like BK7. These will generally have the lowest reflections because multi-coating technology gets more and more difficult to apply in high index glasses like Lanthanum and dense flints. These high index glasses are used to provide large aberration free fields, but they require the utmost care in the coating design and manufacture.

This is generally where the manufacturers cut corners to either save money or to speed up the process (to save money). As long as you, the purchsing public does not know this, they will take every advantage they can get because this is a super competitive field.

Roland Christen