Nikon's 4x CF/CF N Plan Achromat

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NikonUser
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Location: southern New Brunswick, Canada

Nikon's 4x CF/CF N Plan Achromat

Post by NikonUser »

With Winter approaching I have an ambitious plan to 'characterize' my macro-type lenses; essentially working out a range of magnifications that I can get with each using a Nikon PB-6 bellows.
This Nikon 4x CF/CF N Plan Achromat is my latest aquisition. The CF/CF designation is how Nikon describes the lens in its 1989 brochure. The N designation means 'larger N.A.'; for this lens 0.13; 0.10 for non-N lenses.
Image

One of 7, 4x microscope objectives introduced by Nikon in their February 1989 Brochure "New CF LENSES",
and not to be confused with the other 6:
4x CF/CF N Plan Apochromat,
4x CF E Plan Achromat,
4x CF Achromat
4x CF E Achromat
4x CF/CF N Plan Phase-Contrast
4x CF strain free Achromat P

Image #1: At minimum bellows extension (140mm) the full frame image is about 6.6 mm on longest side and is 4,288 pixels. About a 3.6x magnification on the sensor.
Image

Image #2: An 800px selection.
Image

Image #3: At maximum bellows extension (300mm) the full frame image is about 3.03 mm on longest side (4,288 px). About a 7.8x magnification.
Image

Image #4: An 800 px selection.
Image

All are ZS PMax stacks

Other images and discussion
HERE
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

Nikon camera, lenses and objectives
Olympus microscope and objectives

NikonUser
Posts: 2588
Joined: Thu Sep 04, 2008 2:03 am
Location: southern New Brunswick, Canada

Post by NikonUser »

In a question re: minimum magnification one can get with this lens.
It's probably about 3x without vignetting. When mounted directly onto a camera body (24mm sensor) it vignettes at 2x but image quality remains good/excellent.
Quick & Dirty single frame:
Image
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

Nikon camera, lenses and objectives
Olympus microscope and objectives

Enoplometopus
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Nikon 4x objective

Post by Enoplometopus »

Hi

Based on your experience with Nikon 4x objectives, which one do you regard as the best one out of the choice you have, and which one would you recommend for someone who wants to spend less but get good quality? How important or advantageous is it to choose an Apochromat vs. Achromat?

Cheers, Daniel

NikonUser
Posts: 2588
Joined: Thu Sep 04, 2008 2:03 am
Location: southern New Brunswick, Canada

Post by NikonUser »

A difficult question.
The Apo has better resolution, but only marginally (Rik posted an interesting graph comparing the Apo & Achro, but I can't locate it)
The Achro can be bought for about $250.00, whereas the Apo goes from anywhere between $500-$1,000. Apo is nice if you can afford it.
Not sure that you see any real difference in output between the 2 lenses, the Achro is an excellent lens and is likely all you need.

There are several other ways to get excellent 4x magnification at usually much less cost than with a 4x objective, for e.g.,:
The older MF 105mm Micro Nikkor with manually set f-stops;
An older model 28mm f/3.5 Nikon lens with manually set f-stops

See HERE for images from the 28mm

See HERE for the 105mm

There are other lenses that give excellent results at 4x.

Theoretically, and most likely practically, Apo's are the best lenses.
Take a look at Charles Krebs fantastic images through a microscope,
and note that almost all his lenses are Apo's.
NU.
student of entomology
Quote – Holmes on ‘Entomology’
” I suppose you are an entomologist ? “
” Not quite so ambitious as that, sir. I should like to put my eyes on the individual entitled to that name.
No man can be truly called an entomologist,
sir; the subject is too vast for any single human intelligence to grasp.”
Oliver Wendell Holmes, Sr
The Poet at the Breakfast Table.

Nikon camera, lenses and objectives
Olympus microscope and objectives

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