Do not make the assumption that color effects seen near the edge of the field are false color due to the telescope. The secondary color normally considered the bane of achromats is on-axis out of focus blue and red that combine to form a purple halo surrounding bright objects.
Color at the edge of the field is lateral color. This is caused by a variation in magnification with wavelength and is primarily due to the eyepiece. The Moon is a good test for lateral color. If you just bring the bright limb into the field you will see one color finging the limb. If you have the Moon in the field and move the edge so that it is just about to leave the field you will see a different color fringe. This is likely to be more obvious in a telescope with more aperture since the image is brighter. For best viewing objects should be kept in the center of the field, so lateral color is not a big issue.
Your descriptions show you are seeing more with the AP130, and a TV 127 is not going to show you any more. In quality telescopes, aperture tells the story. I'd give the 130 more time. I presume you have been using the 102 for a while, in which case your eye/brain is used to that brightness level, and you may not yet be seeing all that the 130 is capable of revealing. Don't base you opinion on one or two nights - use the 130 often and see what happens.
Clear skies, Alan
Color at the edge of the field is lateral color. This is caused by a variation in magnification with wavelength and is primarily due to the eyepiece. The Moon is a good test for lateral color. If you just bring the bright limb into the field you will see one color finging the limb. If you have the Moon in the field and move the edge so that it is just about to leave the field you will see a different color fringe. This is likely to be more obvious in a telescope with more aperture since the image is brighter. For best viewing objects should be kept in the center of the field, so lateral color is not a big issue.
Your descriptions show you are seeing more with the AP130, and a TV 127 is not going to show you any more. In quality telescopes, aperture tells the story. I'd give the 130 more time. I presume you have been using the 102 for a while, in which case your eye/brain is used to that brightness level, and you may not yet be seeing all that the 130 is capable of revealing. Don't base you opinion on one or two nights - use the 130 often and see what happens.
Clear skies, Alan
