Considerations in selecting a lens for a large format camera sensor

For most cameras in the automated imaging marketplace, the sensor sizes are 1” and less. (1″  sensors have 16mm image circle/diameters)

Note the size in inches and the image circle size in millimeters do NOT match!  1” does not convert to 16mm!.  But that is a topic for another blog post!)

Industrial cameras with C/CS mount sensors normally range from ¼” to 4/3” ( up to 22mm image circle, which is the largest a C mount is by definition).

However, there are many cameras that have sensors larger than this, with many being a full 35mm sensor.  These sensors typically require larger F or EF mounts as seen in the picture above.

Click here for F-mount lenses from Kowa

Click here for F-mount lenses from Schneider

The question becomes, how do you find a suitable lens for these cameras?

First, let address the Issues with F mount lenses

The mount most commonly used by camera vendors for sensors larger than C mount are F mounts.  F mounts are most popular mount for SLR cameras, designed by Nikon about 1960. https://en.wikipedia.org/wiki/Nikon_F-mount

F mount lenses for commercial and consumer/prosumer cameras are excellent optically and priced well but there are several issues you need to consider with these lenses for automated imaging applications.

  1. First, F mount lenses are bayonet, not screw mount. That means they are not as secure as C mount, and therefore, much more prone to vibration, or even coming lose.
  2. F mount lenses for the consumer/prosumer market are designed to take fantastic color pictures. To do this, the lens coatings are optimized for color. This can affect mono images.
  3. Consumers want their cameras to be light, so the F mount lenses are made with as much plastic as possible. This is not great for industrial applications
  4. These lenses are designed for automatic focus and exposure and have controls for that in the lens itself.
  5. Finally, the last issue is that many of these lenses are designed for the automated controls with prosumer cameras, autofocus and autoexposure.

If you can find an all metal manual F mount lens from 20 to 30 years ago, it would be great for an industrial application!  If not, we suggest you turn to one of the companies that make F mount lenses specifically for this market. The major vendors are Schneider, Edmund Optics, and Kowa.  All have a series of F mount lenses that are much more rugged than a prosumer F mount lens, and also don’t have the extra controls for automatic focus/iris.  They have lock screws as well to hold their settings.  The major limitation to these lenses are that they cost more than prosumer lenses, and are in just a small range of focal lengths.

Contact us for further specifications and pricing

EF Lenses

Since many of the new large format lenses can be controlled electronically via the camera, the automated imaging industry has created several products to use these lenses. The solutions from Birger Engineering, www.birger.com are straightforward to use. They make a mount that attaches to the  camera and allows for the use of EF mount lenses.  Attached to their mount are connections to drive the lenses, via serial commands with their SW.  Several camera manufacturers have built cameras with EF mounts as part of the camera.  This is an especially nice solution since there are no wires hanging out for control, and the lens is controlled directly from the camera’s SDK.

This provides a high level overview of the considerations in selecting a lens and size for large format camera sensors.  1st Vision has extensive knowledge with lenses and cameras and will help you in the selection process.

Please contact us and discuss your application with our sales engineer! 

Related Blog posts:

Canon EF mount integrated into Allied Visions GT1930L

Imaging Basics – Calculating lens focal lengths

Not all lenses are created equal!

Low cost, entry level camera, but full featured! Learn about the new VGA, 138 fps, USB3, global shutter camera from IDS priced below $400

Low cost imaging just got redefined with the new IDS UI-3130 LE USB3.1 model cameras.  Typical entry level cameras previously had very few features, until now.

IDS Imaging has released the UI-3130LE USB3.1 camera with the 1/4″ ON-SEMI Python 480 global shutter sensor.  Providing 138 fps at full resolution and 420 fps with the 2X sub-sampling feature, the new series provides a great low cost entry level camera at 0.5MP resolution, and packed with many features



The new IDS UI-3130LE cameras are available in board level, board level with S-mount or fully housed configurations with monochrome and color sensors.  The ON-SEMI Python 480 with 4.8um pixels is one of the latest image sensors providing low noise, high Quantum Efficiency and great sensitivity. 

Feature Highlights

Even with at a entry level cost, the UI-3130LE is packed with features such as 4X Multi Area Of Interest (AOI), long exposure settings to 5 seconds and Type C USB3.1 allowing external power output.


High Dynamic Range (HDR) is included in the UI-3130CP model to address difficult imaging scenes where its desired to see the darks and brights without saturating or being too dim.


Example:  Image to the right uses various “kneepoints” allowing HDR to be achieved


The HDR mode utilizes kneepoints, where the exposure time is divided into sections. After each section, excessively light pixel values are reduced to a limit value and briefly post exposed. This prevents overexposure and increases the dynamic range.

The uEye LE USB 3.1 Gen 1 is the first USB 3.1 Gen 1 industrial camera with a pioneering, reversible USB Type-C connector which supports USB Power Delivery for the first time. The board-level versions also has a 10-pin I/O SMD connector for GPIO, trigger and flash. Via USB Power Delivery, it is possible to provide a variable peripheral power supply to the camera’s I/O connector.

The new LE’s will also soon support liquid lens technology for OptoTune and Varioptics lenses.. Contact us to learn more about this upcoming feature.

 



Related Posts

Everything you need to know about USB3.1

USB3.0 for Machine Vision?  Absolutely – White Paper 

Please do not hesitate to Contact us!  1st Vision can provide a complete solution including cameras, lenses, lighting and cables.  We have over 100 years of combined experience we can put to work for you!


Ph:  978-474-0044
info@1stvision.com
www.1stvision.com  


Battle of the 2 Megapixel Image sensors – Sony Pregius IMX174 vs Starvis IMX290

Sony has continued to improve image sensors, first with the debut of the Pregius sensors and now with the low light sensitive Starvis sensors. The Starvis sensors are slowly being released by camera manufacturers and IDS Imaging is the first to release them in the new LE USB3.1 models.

These new camera sensors are being released at an astonishing rate, which is great for the imaging market, but making it harder to make decisions in identifying the best sensor for an application.

1stVision is continuing to compare Sony image sensors to help make these decisions easier!

We have put two more sensors into the boxing ring to battle it out and see how they fair in various categorizes. In this contest, we put the Sony Pregius IMX174 (and essentially its sibling, the IMX249) and the new Sony Starvis series, specifically the 2.1MP IMX290 in the ring.  

The Sony Starvis has become very interesting in applications that require very low light sensitivity and are attractive due to the back side illuminated architecture. As seen in the diagram below, the metal wiring has been set behind the photodiode and decreasing the distance light has to travel. This new pixel design lends itself to improved sensitivity.






















Diagram courtesy of Sony

The chart below compares some key attributes of the Sony Pregius IMX174 & IMX249 image sensors 

Sensor Comparison Chart



Round 1 –  Sensitivity:  Absolute sensitivity is a great way to identify low light performance.  Using the “Absolute sensitivity” figures above, we see that the IMX290 sensor takes less photons to register the smallest detectable amount of light.  In this round, we see that the IMX290 has a lower value of 8.5 vs 12.1 (less photon’s needed) lending itself to the winner in this round for best low light sensitivity.   In essence, we can start to form an image in lower light with the IMX290.  

Round 2 – Quantum efficiency (QE):  QE is the ability to turn photon’s into electrons at given wavelengths.  In this round, we see that the IMX290 has a better efficiency of 65.9% vs 59.2% in converting photons into a charge again winning the round.  This means more signal is provided for that given wavelength, creating a brighter image.  

Round 3 – Saturation Capacity:  This value is essentially the size of the pixel well measured in electrons.  The larger the well, the better is can drown out noise and not saturate quickly.  The IMX174 excelled in this round.   In turn, you see the dynamic range is higher at 73% vs 66%.  In cases where you would like to see the brights and the darks in a scene, higher dynamic range is desired.  

Conclusion:  In the end, its really a draw between the two sensors.  In the 2MP range of these sensors, it really depends on your application!

If you need low light sensativity, the Sony Starvis family of sensors excel due to the pixel architecture.  You’ll find the Sony Starvis currently in the IDS LE3.1 model cameras in the following cameras with 2 and 6 MP resolutions with more on the roadmap.

2MP – UI-3860LE
6MP – UI-3880LE  

If you need more dynamic range, the Sony Pregius IMX174 and IMX249 are the best CMOS sensors on the market today.  (As a note, the IMX174 and IMX249 are identical, but the IMX174 being a faster version and a bit more costly than the IMX249).  You’ll find these sensors in the several camera lines hosting the Sony Pregius sensors.


Interested in other sensor comparison?  Click below!

IMX174 vs CMOSIS CMV2000 – CMOS battle between 2MP Sony Pregius and CMOSIS

IMX250 vs ICX 625 – 5MP’s sensor battle between Sony’s older CCD vs new CMOS model

Interested in the EMVA1288 Data?  IDS can provide this data upon request, email me (jonc@1stvision.com) if you are interested in receiving the data for one of the cameras.  


Please do not hesitate to Contact us!  1st Vision can provide a complete solution including cameras, lenses, lighting and cables.  We have over 100 years of combined experience we can put to work for you!


Ph:  978-474-0044
info@1stvision.com
www.1stvision.com  

               

How do you get the most pixels for your money? Check out the new Dalsa Nano C4900 camera!


Teledyne Dalsa has continued expanding its Genie Nano GigE vision camera series. Introducing the Nano C4900 GigE camera based on the ON Semiconductor AR1820HS 18 Megapixel Back Side Illuminated (BSI) image sensor with a resolution of 4912 x 3684.

Attractively priced below $600, this just may be the most pixels for your money!

Furthermore, Teledyne DALSA’s “Burst Acquisition” feature provides frame rates of 13 fps @ 18MP pixels resolution while maintaining superb image quality!





 

If the attractive price for 18 MP is not enough to get you excited, there are a few other aspects of this camera worth discussing further.  

 

  • Back Side Illuminated Technology (BSI):  If we were to look at this sensor 5 years ago and see a pixel size of 1.25um, we’d assume that is not light sensitive.  On the contrary as ON Semiconductor flipped the pixel upside down!  Traditional image sensors were front illuminated where the photo detectors were towards the back of the pixel stack.  In turn, there was loss in this method as it interfered with overall light reaching the detector.  Back side illuminated sensors have the same elements, but the photo detector was moved forward to not have as much loss due to internal wiring and reflections.  BSI technology improves the change of photons being captured from 60 to 90% on average providing high sensitivity even in small pixels!
  • Burst Acquisition mode:  The Nano C4900 has 200 MB of internal memory allowing image capture at higher rates exceeding the GigE bandwidth for periods of time.  This mode is very useful for applications needing a rapid series of images at intervals.  
  • Rolling Shutter with Global Reset:  Rolling shutter image sensors have the benefit of lower cost typically, but are limited to stationary objects due to image distortion. However, thanks to a the global reset feature, distortion is minimized by allowing all the lines to be exposed with read out of the lines there after.  
  • Extended Operating Temperature range:  Nano cameras have an operating case range of -20 to 60 deg. C.  This provides higher temperatures versus the competition. 
  • 1 / 2.3″ Image Format: High resolution cameras typically have relatively large formats which increases the cost of lenses.  As the pixels are relatively small, the image format is only 1/2.3 allowing lower cost lenses to be used.  


18 Megapixels, 13 frame/sec, high sensitivity, overall low cost creates possibilities!  

Applications may include: 

  • Low light, high magnification medical applicications
  • Industrial Metrology
  • Intelligent traffic solutions (ITS)
  • Microscope applications
  • Unmanned Aerial

Need high resolution, global shutter cameras still in a compact format?   Dalsa is now shipping the following new high resolution cameras: 

Dalsa Nano M4020 (IMX304) – 12MP,  4112 x 3008, 20 fps

Dalsa Nano M4030 (IMX267) – 9MP, 4112 x 2176, 30 fps

See the complete Teledyne Nano camera line here

As the old saying goes, “A system is only as strong as its weakest link”.  As a reminder, do not let your cables be your weak link!  

Be sure to use our new industrial GigE Cables – Click here NOW!

Please do not hesitate to Contact us!  1st Vision can provide a complete solution including cameras, lenses, lighting and cables.  We have over 100 years of combined experience we can put to work for you.  

Ph:  978-474-0044
info@1stvision.com
www.1stvision.com  

BSI Image courtesy of Solid State Technology Magazine

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