I have a Celestron powerseeker 127 Eq telescope viewing issues
With the setup you have, you are attempting a magnification of x 750, which is way beyond the capabilities of your scope. A realistic limit to usable magnification is x 250, or about what you will get if you take the barlow off and just use the 4mm lens.The 127mm aperture on that scope does not gather enough light to do more.
Even that depends on good seeing, that is, clear air and no light pollution. It is a great shame that scopes are marketed with outlandish claims as to magnification. You certainly will see a magnification of x 750 in daylight, when there is lots of light, but they don't tell you that trick.
I have a 200 mm scope, with a practical limiting magnification of x 400, and I find that almost impossible to use. The viewing object is hard to find and keep centred in the eyepiece, it wobbles around, it soon disappears due to the rotation of the heavens, and is dim and blurry. I keep to magnifications of about x 250 max.
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