The Big Surprise
A couple of weeks ago I picked up a new objective on eBay that had all the right specs but I was really doubtful about the image quality, just how much sharpness and correction can a buyer expect for $17? I felt lucky so I ordered the lens anyway and took the risk. Once I had a chance to make a few images with the lens, as you can see below, it turns out that $17 buys a hell of a lot of image quality in 2017.
Multicolored pencil tip at 4X. Uncropped 5 image stack handheld. Plan 4x Objective on Nikon D810 1/60s manual mode ISO 100 single flash at 1/32 power.
Why a microscope Objective?
For magnifications of 4x and higher I prefer to use to microscope objectives. They are a great cost effective way to move into high magnification macro photography. They are designed to cover a certain magnification range and a small field at the highest resolution where normal lenses must cover a bigger range and larger field but at a lower resolution. The downside to using objectives is that they have a very shallow DOF because of their large apertures and lack of an aperture so they are best used for flat subjects or for 3D subjects you would want to use image stacking best results.
Image Quality
Amazingly this objective produces clean sharp details across the frame. Chromatic aberrations, purple and green fringing, are almost unnoticeable and very well controlled. The CAs or chromatic aberrations are better corrected than some expensive objectives that I have tried and easily removed using post processing software. Flare is very well controlled thanks to a deep barrel and recessed front element. Corner performance is decent. Field curvature was flat as it should be for a Plan objective. Excellent results overall.
FYI most finite type microscope objectives are designed to be used with eyepieces that correct for chromatic aberrations. Nikon CF, CFI and a few Olympus finite objectives are corrected for CAs within the objective so they make great lenses for macro photography.
More information
If you would like to see more images made with this lens and get a lot more information, follow this direct link:
https://www.closeuphotography.com/seventeen-dollar-plan-4x-objective
Or its easy to follow the navigation on the column on the left: Equipment > Objectives > then click on the Generic Objectives thumbnail
Young sub-adult green Aphid. Uncropped handheld single image. Plan 4x Objective on Nikon D500 1/200s manual mode ISO 100 single diffused flash at 1/32 power.
Top and bottom view of the Plan 4x Objective supplied by Amscope.