AmScope 20X Plan Achromatic Objective Lens with Knurled Ring

As a beginner (74 year old) I bought a new AmScope T490B-DKO 40X-2000X Trinocular Compound Darkfield Microscope with Oil Condenser, which had 4X, 10X, 40X, and 100X oil, all Four are DIN Achromatic Objectives. Being a beginner I read everything I could on microscopes, and a customer review on the AmScope A20X 20X Achromatic Microscope Objective said, “Excellent objective between 10x and 40x. Great for microlife. Wanted a Plan obj. but not available from Amscope in this magnification. I have to admit I don't miss the fact that it is not Plan. I gladly recommend this objective.”Yes, what he said about a Plan obj. sounded good, and now things have changed, the Plan obj. is now offered. After reading more about microscopes, this ($53.99) sounded better than the simple 20X ($23.99) since I want to use a camera on pond water monsters. It is fun to learn, but I suspect I had over idealized the Plan optics. Today I got a first chance to try it out on a few slides. Yes, it is beautiful, and the views are flat out to the edges, but it was not parfocal with my other objectives. This means that when I go from 10x to 20x I will need to refocus, then when I go to 40x I will need to refocus again.I have mixed feelings so far. I hope in the next few weeks I will get over this irritation, and it will become automatic that I turn the focus in the right direction. I suppose it will be like riding a bike, but for now it is a big distraction. I have yet to take photos, so that may be nice too. It may be that I will change all my objective lens so it will then become parfocal again. But for now I have also purchased a 60x non-Plan so I am running out of places to mount all these objectives. I need to take out the 100x and the 60x to use this new 20x. A more expensive microscope would give me 5 places for objectives, but after all I am a beginner. I will need to do this hobby for a few years and then see where it takes me.I give the objective a rating of 5, because it is beautiful and it seems well made (but I am a beginner). I still have mixed feelings, but I is my fault for not knowing more about focus.

The media could not be loaded. This was clearly a return and NOT NEW as describedFeatures & detailsThis brand new 20X Plan Achromatic microscope objective lens fits common size (DIN/JIS standard) compound microscopesPlan Achromatic CorrectionsMagnification: 20XIt arrived without its protective plastic cover. It was not threaded correctly into the black cap.It has been clearly damaged by someone rotating the objective into the slide or platform of the microscope.It was also dirty on the lens (see attached video and pictures) to the point it almost appeared to be scratched.I really hope it wasnt someones semen i had to clean off this "BRAND NEW" objective lens.Beyond paying full price for a used item and the damage to the housing of the lens, the objective itself works fine.Dont lie and say what you are selling is new!

It’s okay, not great

Very nice objective. Broad flat field. Great for hunting protzoans.