coinimaging.com Blog

New lens test: Nikon 55mm f/3.5 AI micro-Nikkor

Administrator — Fri, 20 Apr 2012 15:38:08 +0000

Just posted this lens test. It is a good macro lens that shows very high resolution and sharpness. It lags a little behind its more modern brethren in the areas of corner sharpness and chromatic aberration. The problems are countered by its price, typically around $100 in good used condition. See the full test at the link below.

http://coinimaging.com/n55-35.html

Added a couple new lens test recently.

Administrator — Tue, 20 Mar 2012 23:57:57 +0000

Added lens tests for the Nikon El-Nikkor 75/4 enlarging lens and the Nikon E Plan 10/0.25 LWD objective. I tested the 75 mm both normal and reverse mounted to see what really works better. I found that the optical principle (based on how the lens was designed to work) that you should use an enlarging lens reversed when above 1:1 and normally mounted when below 1:1 seems to play out in my numerical testing, at least for this lens.

http://coinimaging.com/nikon75.html

http://coinimaging.com/nik10lwd.html

Mark.

New lens test: Canon 35mm f/2.8 bellows lens

Administrator — Wed, 22 Feb 2012 03:42:27 +0000

Just added the Canon 35mm bellows test to my lens test page. This is great lens that is highly recommended for high-magnification macro work.

http://coinimaging.com/can35_bel.html

New lens test: Nikon 105/4 AIS micro

Administrator — Thu, 08 Dec 2011 01:13:32 +0000

Added a new lens test today.

http://coinimaging.com/nikon_105-4ais.html

All lens tests have been updated with the new graphs.

Administrator — Sat, 03 Dec 2011 17:50:23 +0000

I have adding my new graphical ratings system for sharpness and resolution to all of my existing lens tests. Not sure what other new tweaks I can add. I will probably add axial CA images to the older ones as … Continue reading →

A new addition/change to my lens testing.

Administrator — Tue, 22 Nov 2011 22:26:51 +0000

I have been working on a ratings scale for lens resolution/sharpness performance. I created a graphical system based upon all of the lenses that I have so far tested (60+ total). I have curves that correspond to fair, good, very good, and outstanding for resolution and sharpness. When a particular lens’ curve is placed over this template it will give you information about how that lens compares against other lenses at a specific magnification. I have added these graphs to the newest test – Nikon CF-N PlanAPO 4x/0.20 microscope objective. I plan on adding these graphs to the other already completed tests in the near future.

A note on how to use these ratings: A rating of fair doesn’t mean that the lens stinks, it just means that there are other lenses out there that will provide more sharpness and resolution at a particular magnification. Longer focal lenses will tend to score more poorly at any given magnification compared to shorter focal length lenses. I may still want to use a longer focal lens because it has superior working distance.

New lens test: Nikon CFN PlanAPO 4x/0.20

Administrator — Tue, 22 Nov 2011 22:23:41 +0000

Just posted this test today. This lens is the bestest of the bestest from 3:1 to 6:1.

http://coinimaging.com/nikon_4apo.html

New lens test: Spiratone 35 mm f/3.5 enlarging lens

Administrator — Mon, 14 Nov 2011 01:45:40 +0000

After a little vacation from lens testing, I just put up a new lens test today. I was surprised how well this lens actually performs since I only paid $5 for it.

http://coinimaging.com/spir35.html

Moving my optics articles

Administrator — Sat, 10 Sep 2011 18:41:58 +0000

I have been steadily moving the blog postings that I made on optics over the last couple of years. I am moving them to their own webpage where they will be easier to navigate.

they can be found at:

http://coinimaging.com/optics_articles.html

Finally got the Minolta 12.5 f/2 bellows lens test done.

Administrator — Sat, 13 Aug 2011 18:13:40 +0000

The Minolta 12.5 f/2 bellows lens test is finally online at:

http://coinimaging.com/min12bel.html

It was kinda slow going with the testing since I have been busy at my real job lately. the other reason is that high magnification testing is often time consuming. Testing the aperture at f/8 and a magnification of 9:1 results in a shutter speed of 15 sec. I have to take 40 or 50 pictures to make sure that I get the numbers I want. that means it goes slowly.

not sure what I will test next.