Kilfitt Makro-Kilar 40mm Lens Review - Popular Photography's 1955 Dream Lens (as close as it gets)

A detailed review and historical documentation of the Kilfitt Makro-Kilar 40mm standard prime lens in f 3.5 and f 2.8 specification.
In December 1955, Popular Photography Magazine stated:
"WHAT'S YOUR DREAM lens? A needle sharp f/1 which you could use for wide-angle, normal and telephoto shots at will? All this in one neat package of optical glass which you could focus on a bug at two inches or a mountain at infinity-with generous depth of field at both extremes? This lens hasn't been designed yet, but the closest thing to it is the new, compact, f/3.5, 40mm Makro-Kilar which will fit most popular 35mm single-lens reflex cameras accepting interchangeable lenses."
Released some 70 years ago, Kilfitt Makro lenses are historically significant for being the first commercially available fully integrated macro lens, for 35mm SLR cameras.
Revolutionary for their time, Kilfitt lenses are today renowned among collectors and connoisseurs, for their unique rendering capabilities, fine tactility, and faceted functionality.
Chapters
00:00 - Introduction
01:02 - Heinz Kilfitt Historical Context
03:08 - Macro Photography
04:12 - Production Locations & Lens Markings
06:39 - Specifications
07:27 - Lanthanum Glass
07:46 - Lens Type Designation
09:25 - Focusing Measurement
09:48 - Depth of Field Parameters
10:02 - Rotating Helicoid Mechanism
10:39 - Preset Aperture Lenses
11:21 - Lens Weights & Measurements
12:05 - Lens Markings
12:47 - Apochromatic Specifications
13:27 - Lens Mount Options
13:55 - Fliters
14:56 - Lens Coatings
15:34 - Accessories
15:52 - Mirrorless Application
16:19 - Pricing
17:25 - Build Quality
18:13 - Mechanical Movements
18:29 - Rubber Focus Ring
19:02 - Focus Ring Rotation
20:07 - Kilfitt Test Process
20:51 - Lens Weaknesses
23:08 - Applications & Reference Articles
23:52 - Alternatives
24:47 - Performance
25:05 - Sharpness F3.5 Lens
25:54 - Sharpness F2.8 Lens
26:50 - Distortion
27:15 - Vignetting
28:20 - Colour Rendition
29:04 - Chromatic Aberration
29:29 - Comatic Aberration
29:48 - Bokeh
31:01 - Focus Transition
31:20 - Halation
31:45 - Lens Flare
32:40 - Conclusion
Lens: Kamerabau-Anstalt-Vaduz Kilfitt-Makro-Kilar 1:3.5 / 4cm
Lens: Heinz Kilfitt Munchen Makro-Kilar 1:2.8 / 4cm
Adapter: Fotodiox PRO EXA-Sony E
Camera: Sony A7r IV
Adaptable to Panasonic, Sony, Nikon, Leica, Canon and Fujifilm mirrorless cameras.
www.durlacher.me
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[@w0lfyovi294]

Absolutely amazing work. One of the most comprehensive reviews I have ever seen.

[@durlacher3524]

Many thanks @w0lfyovi294, very much appreciated. I was a little concerned it might have been too much information, however I wanted to make sure I covered everything off. Notably, having discovered that quite a bit of the information floating about online pertaining to the Kilfitt lenses is inaccurate (or close but not quite right) it's an opportunity to provide an update that hopefully will be useful for those wanting to know more.

[@w0lfyovi294]

@@durlacher3524 I absolutely love the background story and details, especially about the optical engineers making these lenses and the physics around it. You are doing what I dreamt of doing for many years (but I have other priorities and interests now). I started looking for some of these lenses to buy because they are so unique and interesting.

[@ArminHirmer]

interesting, thank you

[@durlacher3524]

Many thanks for commenting, very much appreciated.

[@Snikkelbek]

Great video, thanks!

[@durlacher3524]

Hi @Snikkelbek, greatly appreciate your comment. A lot of time and research went into this knowing it would be of interest to a rather small yet discerning viewership, The positive feedback is encouragement to continue making more reviews.

[@spectralcav]

Good work! Obviously a ton of research went into this.
I noticed an Edixa branded 4cm lens - the only other one I've seen other than my own copy ;-)
As you mentioned, they measured focusing distance from the front of the lens rather than to the film plane; not sure if any other manufacturer used those specs or if that's a quirk unique to Kilfitt?

[@durlacher3524]

Hi Spectralcav, many thanks for your comment and noted on the Edina branded lens, quite the rarity! With regards to the close focus distance, it seems to be specific to the Kilfitt Makro lenses. The reality being that the 5cm close focus distance quoted for type D lenses ends up being around 20cm from the film or sensor plane when the lens length and flange focal distance is added - still pretty remarkable for 1955!

[@majorkong7388]

Outstanding work. I look forward to more videos!

[@durlacher3524]

Thankyou @majorkong7388, appreciate your feedback! More videos to come, hopefully they wont take as long to research and produce (the Kilfitt review was some 6 months in the making).