The Linos inspec. x L 5.6/105 was developed for high-resolution extra-large 12K line scan camera sensors (12,000 pixel wide, 5.0 μm pitch sensor) used to find small flaws, smaller than 10 μm, directly within the production process of FPDs (flat panel displays), and PCBs (printed circuit boards). These lenses were widely used in the industrial market in Asia for the last 5 years so the prices on the used market have been dropping steadily. New the lenses cost $1395, but I recently paid $299 USD for a used copy with free Fedex overnight from a seller in S. Korea in June, 2020!

The inspec. x L 5.6/105 lens is available in types optimized for ß (magnification) 0.33x, 0.5x, 0.76x and 1x magnification, respectively. This is the ß 0.33x type, the version that seems to be most commonly seen on the used market. Due to the slow maximum aperture and long focal length this is not an ideal lens for work in reverse at 3x due to diffraction but thanks to the large image circle and chromatic aberration correction this lens works well as a tube lens for a stacked lens configuration or for work with an infinity corrected objective.

This test, like all the content on my site, is completely independent and free from industry influence. I will not benefit from your purchases. Most photo sites in the web today are run by corporations for profit. I do not show ads, use any affiliate links, track your web history, sell products or take money from anyone in the photo industry. I create content for this site for fun in my free time. Instead of making a few dollars from this site, I'm far more concerned about teaching people to learn to use what they already have, rather than waste time and money buying the wrong equipment. Most of us, myself included, would make far better pictures if we'd stop buying new equipment and spend that time learning how to use what we already have instead.

There are some cosmetic differences between the older lenses, left, and the newer inspec.x L 5.6/105 lens, right, as you can see above.

KEY FEATURES OF THE inspec.x L

All metal barrel with locking aperture ring
Excellent CA suppression
46mm diameter V-mount (V46)
Flat image field with minimal corner shading
82mm image circle means the lens can cover up to medium format sensors
Each lens is marked for best azimuth position to achieve the lens’s absolute highest resolution and contrast
The V-mount makes it easy to align the lens to the best azimuth mark

PROS AND CONS

What I really like:
Excellent fit and finish
Locking aperture ring
Good chromatic aberration suppression
Dual V46 mount and M43 x 0.75 thread mount on both sides
Low used market prices
Very clear barrel markings

What I dislike:

Slow maximum aperture
Large diameter barrel

TECHNICAL SPECIFICATIONS

inspec.x L 5.6/105 -0.33x line scan lens
Order Number: 0703-085-000-20
Type: Industrial Large format 12K Line scan
Focal length: 105mm
Maximum aperture: f/5.6
Sharpest Aperture: f/5.6
Aperture range: f/5.6 - f/11
Coverage: 82mm image circle
Distortion: < 0.4%
Sensor pixel size: 5 μm
Manufacturers recommended magnification range: ß 0.33x (ß 0.45…0.25x) forward and ß 2.5x - 3x in reverse
Wavelength range: 400nm - 750nm
Lens mount: V-Groove, 46mm (V46) and M43 x 0.75 threads
Filter thread: M43 P= 0.75mm
Source: Lens made in Germany
Design includes cover glass: Yes, 0.76mm D263
Suggested retail price: $1395 (Other inspec. x lenses for comparison: inspec.x L 4/105, $2429, inspec. x float lens $3429)

0.3x Test: Cosina 100mm f/3.5 Macro vs Sigma 70mm f/2.8 Macro vs inspec. x L 5.6/105 Line Scan Lens

**inspec.x L 5.6/105 line scan lens, Cosina Plastic Fantastic 100mm f/3.5 AF macro lens, and Sigma 70mm f/2.8 DG Macro lens**

TEST SET-UP

inspec.x L 5.6/105 line scan tested lens at f/5.6 mounted as marked (0.33x arrow towards the sensor)
Cosina 100mm f/3.5 macro lens tested at f/5.6 mounted normally
Sigma 70mm f/2.8 macro lens tested at f/5.6 mounted normally

Note that Cosina makes the 3.5/100 macro lens but it was also sold with the following private labels over the years:
SMC Pentax-FA 100mm f/3.5 macro
Tokina AF 100mm f/3.5 macro
Vivitar 100mm f/3.5 macro
Promaster Spectrum 7 lens 100mm f/3.5 macro
Phoenix AF 100mm f/3.5 macro
Soligor MC Macro 100mm f/3.5 macro
Voigtlander Macro-Dynar AF 100mm f/3.5 macro

Camera: Sony α6300, model # ILCE-6300, also known as: A6300
Sensor size: APS-C. 23.5 × 15.6 mm. 28.21 mm diagonal. 3.92 micron sensor pitch
Flash: Godox TT350s wireless flash x 2 with one Godox X1s 2.4G wireless flash transmitter
Vertical stand: Nikon MM-11 with a Nikon focus block

For this test a stack of images was made with 0.2mm (200 micron) steps. The sharpest frame was then chosen using Photoshop at 100% actual pixel view. Separate images were selected for center, edge, and corner if needed. Each image was processed in PS CC with identical settings with all noise reduction and lens correction turned off, all settings were zeroed out (true zero) and the same settings were used for all of the images. All of the images shown here are single files.

100% View Center Crops at 0.3x

Center-crop-100-percent-view-0.3x-www-Closeuphotography-com-17832.jpg

All three lenses here used identical diffusion and lens hoods for this test. In the center the Cosina is the weakest of the three, the Sigma is sharper and more contrasty but also shows more chromatic aberrations. The inspec.x L lens is the sharpest and best corrected for CAs in the center. The Cosina macro lens can be found for less than $100 used, the Sigma 70mm runs in the $200 range, the inspec.x L 5.6/105 is right under $300.

100% View Corner Crops at 0.3x

Corner-crop-100-percent-view-0.3x-www-Closeuphotography-com-17832.jpg

Both the Cosina and Sigma show a drop off in corner sharpness with some field curvature. The inspec.x L image is flat, free from CAs, with almost no perceptible change in sharpness from center to corner. The inspec.x L image is the best lens at 0.3x; sharp, flat, clean, and free from CAs.

Inspec.x-L-5.6-105-Line-Scan-Staeble-Magnogon-SK-Componon-S-100-Lens-www-Closeuphotography-com.jpg

Tube lens test at 3x: inspec.x vs Componon-S vs Staeble Magnogon R

Front lens: Schneider Kreuznach 4/35 Componon lens reverse mounted

Rear lenses:
Inspec. x L 5.6/105 line scan lens mounted in reverse and as marked
Schneider Componon-S 5.6/100 line scan lens in BLV-L mount mounted normally
Staeble Magnogon R 5.6/105 repro lens mounted in reverse

TEST SET-UP

Camera: Sony α6300, model # ILCE-6300, also known as: A6300
Sensor size: APS-C. 23.5 × 15.6 mm. 28.21 mm diagonal. 3.92 micron sensor pitch
Flash: Godox TT350s wireless flash x 2 with one Godox X1s 2.4G wireless flash transmitter
Vertical stand: Nikon MM-11 with a Nikon focus block

For this test a stack of images was made with 4 micron steps. The sharpest frame was then chosen using Photoshop at 100% actual pixel view. Separate images were selected for center, edge, and corner if needed. Each image was processed in PS CC with identical settings with all noise reduction and lens correction turned off, all settings were zeroed out (true zero) and the same settings were used for all of the images. All of the images shown here are single files.

Center 100% View Crop

Very good sharpness out of the all three lens combinations with minimal chromatic aberrations. Click on an image to see the file at 100% view in a new window or tab.

The Componon-S seems to be slightly sharper micro-lettering than the other two lenses combinations at 3x. Click on the image to open a full size 1500 pixel version.

Right of Center 100% View Crop

All three lenses are also very close here off-center.

Right-of-center-100-percent-crops-www-Closeuphotography-com.jpg

The Componon-S seems to be slightly sharper off center where the Magnogon seems to show more CAs around the 2-15.

Corner 100% View Crop

The Componon-S looks to be sharpest in the corners with Magnogon the least sharp of the three.

Looking at the details in the lettering Dallas Semiconductor and the circle-A it looks like the sharpest lens is the Componon-S with the inspec. x a close runner up with the Magnongon behind. Looking at 3-16 it looks like the inspec.x has least CAs of the three, the Magnogon the least sharp with the highest amount of CAs, see 3-16. For the record I tried the Staeble lens in both directions and the best results were with the lens reversed.

Final Thoughts on the 3x Test Results

The center crop results were very close, too close to call, but in the corners the Componon-S was sharpest with the inspec.x L doing the best job suppressing chromatic aberrations. The inspec.x L 5.6/105 is highly recommended without any reservations at all.

The first time I tried inspec.x L lens in 2015 I was disappointed and returned the lens to the seller. The performance was not worth the price at the time. In 2015 were uncommon and the prices were around $600+ USD. Since that time the supply to surplus equipment dealers has increased steadily so the used prices have come way down. The units in this test were $300 with free Fedex priority overnight service, from a seller in South Korea, one of the very best surplus dealers you will find anywhere on the planet by the way! That price is too good to pass up for a late model high-performance lens like this.

Sensor cover Glass

The inspec.x L lenses were designed to work with digital sensors with cover glass in place. Linos even gives the specs for the glass as 0.76mm D263. This should give the newer lens an advantage over older legacy glass like the Componon-S since they were never designed to work with a layer of glass behind the lens so this can lead to more chromatic aberrations, but this effect can vary due to lots of factors . See this LensRentals blog post for more on the subject: https://www.lensrentals.com/blog/2014/06/sensor-stack-thickness-when-does-it-matter/

Lens Data:

Note: All Rodenstock MTF data is computer simulated and is within 10% of a production lens supposedly.

Lenses that almost made it into the test

Rodenstock Rodagon 5.6/105
Problem: Excessive chromatic aberrations

The 5.6/105 Rodagon is common low-cost lens a but a quick test of a preset machine vision sample of this lens gave me disappointing results with excessive CAs. So I returned the lens and did not include it in the test. Also be aware that this sample had a rectangle slit aperture disk, as seen below. The disk was accessible by removing the rear lens cell but the performance was poor. Sometimes machine vision lenses are tuned to work with light bands other than visible.

I thought it would be interesting to compare MTF data from the Rodagon 5.6/105 against the APO-Rodagon-N 4/105. The 4/105 sells for more than 10x the cost of the 5.6/105 (2x the cost new) but according to Rodenstock/Linos MTF data they are closer in performance than anyone would guess! That’s a big surprise!

Rodenstock APO-Rodagon-N 4/105

Unfortunately I don’t have a 4/105 APO-Rodagon-N laying around to to test next to the inspec.x L lens so instead I compared the official lens data. Both Linos, and Rodenstock are now both brands of Qioptiq so the MTF graphs are easy to directly compare. At f/8, the inspec.x L MTF curve is sharper in the center and more consistent across the frame, less performance drop in the corners, than the APO-Rodagon-N at the same aperture. Longitudinal chromatic aberrations (LoCAs) are better corrected on inspec.x L. The inspec.x lens wide-open at f/5.6 outperforms the APO-Rodagon-N both wide-open at f/4 and closed down to f/5.6. The MTF data indicates higher sharpness and better corner performance on a full frame sensor and larger with the inspec.x L lens.

Taking a look at a APO-Rodagon-D lens for fun, here the 5.6/120 results on the right side, it is even less sharp and less consistent across the frame than the APO-Rodagon-N, with slightly worse chromatic aberration correction.