Long Perng 90mm F5.5
I've wanted one of these for a while. In fact I wanted one before I got my Kson ED80. The Kson, although it has minor CA, tends to throw bright rainbow flare from bright stars on photos, so saved my money and bought a LP. This is supposed to be the LP ED "APO" scope.
The good. Firstly the build and machine quality is awesome. Miles ahead of the Kson. The focuser is beautifully smooth and I can hit focus point with ease with the reduction.
The bad. So I slip in my trusty Nagler 13mm Type 6 eyepiece and point it around in daylight. What the ... What's with all the blue / magenta fringe I ask myself? This doesn't look like I'm looking through an ED scope.
The ugly. Maybe night time will be better. Eagerly I wait for nightfall and look for a few objects. CA on everything brighter than mag 4. But this was to be my main photo scope. I point to the Orion nebula and take a frame. Well, see the image for yourselves. Blue focus is about 1 light year away from red and green. And it throws rainbow flare from off axis stars as well.
Is this normal for this model or does mine need adjustment?
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