AmScope SE400-Z Binocular Microscope -- FYI

[JDubU]

I have a new SE400-Z microscope and have been evaluating the eyepieces for it.
It comes with a set of 10x (labeled WF10x/20) and a 20x (labeled WF20x) eyepieces that work with its 1x objective lenses.

I also separately purchased a set of AmScope high eyepoint 10x eyepieces (https://www.amazon.com/AmScope-EP10X30E-Extreme-Widefield-Eyepieces/dp/B005OMK2JI) that are used in AmScope's higher end "ZM" line (e.g. https://www.amscope.com/2x-90x-binocular-stereo-boom-microscope-fiber-ring.html).  After asking, I was told by AmScope tech support that they "should" work in the SE400. 

I can confirm that these EP10X30E eyepieces do work in the SE400 and I prefer them over the ones that come in the SE400-Z package.
Since they are not made for the SE400, they do have some minor compatibility issues.  They have a mounting diameter of 30mm instead of 30.5mm, so they rock a bit in the tubes.  Gently tightening the single mounting screw prevents them from rocking, but can add a very slight tilt relative to the tube.  They also sit higher in the tube since the mounting diameter is smaller than the top lens diameter.  Neither of these mounting issues seem to degrade the image quality.  To my eyes, the image appears noticeably clearer, brighter and larger than the regular 10x eyepieces.  The larger appearance is not the objective's field of view (see below), but rather, the apparent diameter of the image in the eyepiece.  I can also use them with my glasses on (YMMV).

I made some measurements using the three sets of eyepieces:

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Eyepiece:  WF20x
Total Magnification: 20
Minimum Interpupillary Distance:  48mm
Field of View: 10mm
Working Distance: 227mm
Eye Relief Distance:  0mm (!)
Exit Pupil Diameter: 1mm
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Eyepiece:  WF10x/20
Total Magnification: 10
Minimum Interpupillary Distance:  52mm
Field of View: 20mm
Working Distance: 227mm
Eye Relief Distance:  14mm
Exit Pupil Diameter: 2mm
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Eyepiece:  WF10x/22 High Eyepoint (AmScope EP10X30E)
Total Magnification: 10
Minimum Interpupillary Distance:  57mm
Field of View: 19mm
Working Distance: 212mm
Eye Relief Distance:  19mm
Exit Pupil Diameter: 2mm
------------------------------------------

For a description of eye relief distance and exit pupil diameter:  https://en.wikipedia.org/wiki/Exit_pupil

[exe]

They have a mounting diameter of 30mm instead of 30.5mm

I wonder what was the decision behind this change.

[analogRF]

Eyepiece:  WF10x/22 High Eyepoint (AmScope EP10X30E)
Total Magnification: 10
Minimum Interpupillary Distance:  57mm
Field of View: 19mm
Working Distance: 212mm
Eye Relief Distance:  19mm
Exit Pupil Diameter: 2mm
------------------------------------------

so the field of view did not increase with this change?

[JDubU]

Eyepiece:  WF10x/22 High Eyepoint (AmScope EP10X30E)
Total Magnification: 10
Minimum Interpupillary Distance:  57mm
Field of View: 19mm
Working Distance: 212mm
Eye Relief Distance:  19mm
Exit Pupil Diameter: 2mm
------------------------------------------

so the field of view did not increase with this change?

If I look at a ruler under the microscope with these WF10x/22 eyepieces, I see span of 19mm from edge to edge on that ruler.
But compared to the stock 10x eyepieces, that image looks larger and clearer. 
It's like if you were to take one photo of an object but make two prints of it, one print larger than the other.  They both have the same field of view but you can see the detail better in the larger print.