Considerations for Color machine vision cameras using a Bayer filter – White paper

Bayer image
Dalsa Falcon camera

Users of single chip color machine vision cameras have lots of choices in camera features. The following are a few issues relating to these types of cameras that users need to be aware of when they are choosing their camera type.

First, its important to understand how a “single chip” machine vision color camera creates a color image. Thanks to Bryce Bayer of Eastman Kodak, we have the “Bayer” filter mosaic filter pattern that generates a color image through interpolation which is the technique used in most machine vision cameras today.

Bayer filter
Bayer Filter

From a macro view, using the Bayer filter, we collect light onto individual pixels through each of the red, green and blue filters which assigns intensity values. Using various interpolation methods, each pixel uses data from adjacent pixels to determine its color to generate a nice color image.

There are several considerations in color imaging during this process such as:
1 – Bayer conversion – Understanding this is important as it may effect the computer CPU load and image fidelity.
2 – Frame rates – Depending on the color format (ie. RGB vs Raw), you will need to understand how this effects the camera frame rate requirements and camera interfaces.
3 – Color formats – Depending if the application simply wants to identify a blue vs red part vs doing a more in depth color analysis will determine which color format is utilized.

1stVision has published a white paper addressing these considerations in the link below.

Download this comprehensive white paper – “Considerations for Color machine vision cameras using a Bayer filter. Click HERE.

For any color application, there is various color camera technology that needs to be considered first. 3-Chip Color machine vision cameras have advantages over Bayer color cameras in which color fidelity and resolution are superior. Additional resources on each aspect is below:

3 chip color camera block diagram
Block Diagram of 3 chip color camera – Courtesy of JAI

Color Fidelity – If your application requires high color fidelity and trying to detect small differences in color, 3 chip color cameras should be also considered. Learn more in this related blog HERE.

Resolution – Due to the interpolation in Bayer color cameras, the overall resolution is reduced significantly. In applications where resolution AND color are important, 3 chip color cameras provide these advantages. Comparison images and further explanation can be found in this blog HERE.

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Give us some brief idea of your application and we will contact you to
discuss camera options.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera selection.  With a large portfolio of lenses, cables, NIC card and industrial computers, we can provide a full vision solution!

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

Related Blogs:

Which machine vision lens provide ultra-high resolution?

Moritex machine vision lens

The image fidelity achievable from a machine vision camera is only as good as the optics you use! Many of the machine vision cameras used today utilize very small pixels, down to 1.25um. The crispness of the images are a result of the resolution of your machine vision lens, so matching the right lens to the camera sensor is extremely important. We classify the lens resolution in terms of line pairs per millimeter (lp/mm). So, what lenses can help resolve these small pixels?

First, the relationship of pixel pitch can be put in terms of lp/mm as seen in the chart to the right. Machine vision lens manufacturers today typically provide the resolving power on their data sheets to help in the lens selection and ensure your matching the lens to the image sensor. If not matched properly, image contrast will suffer.

For machine vision cameras with small pixels, the Moritex ML-M-UR “Ultra high” resolution lenses are an excellent choice with the capability of resolving pixel pitches down to 2.2um with good contrast.

Click HERE for specifications on the Moritex ML-M-UR series and request a quote

The comparison images below show the Moritex ML-M-UR series compared to a conventional lens with less resolution. As you can see in the cutout of the corner, the contrast is much higher with lenses with high resolving power.

machine vision lenses  - image comparison
Left (High resolution lens) Right (Legacy lower resolution lens)

Lens resolution typically has fall off to the edges of a lens. To maintain high contrast, Moritex has optimized the ML-M-UR series to have good resolving power to the edges of the lens.

The charts below represent the contrast (MTF) corresponding to image height (x-axis ) showing the contrast from lens center to lens edge. The X-axis represents the center starting at zero millimeters and mapping MTF to the edge (furthest right point) The ML-M-UR shown in the left chart demonstrates very good performance across the lens. (A relatively flat line is good!) As a comparison to another lens (right chart), contrast is degraded across the lens from center to edge.

Moritex ML-M-UR MTF

Aside from high resolution, The Moritex ML-M-UR series are a compact, 29mm diameter design and well suited for typical 29mm cube cameras. Additionally the lenses have an anti-vibration design with maximum acceleration to 10G’s.

Click to contact
Give us some brief idea of your application and we will contact you to
discuss camera options.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera selection.  With a large portfolio of lenses, cables, NIC card and industrial computers, we can provide a full vision solution!

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

Related Blog posts

What is a 3D camera and how is it used in machine vision?

A 3D Profile sensor (aka camera) relies on 3D Laser Triangulation techniques that have been around for a long time, but until now were expensive. 3D Laser triangulation a decade ago consisted of using separate components in complicated setups using lasers, lighting, optics and algorithms to capture 3D information. Today, this has become simplified into a single package. Teledyne Dalsa Z-Trak profile sensor puts the optics, lasers and cameras into a single package with comprehensive free software.

Ask us for a quote on Z-trak!

How does the Z-Trak Profile sensor capture 3D information?
As shown in the image below, a laser stripe is projected on the object and imaged on an image sensor. This gives the position of the laser stripe and provides lateral information and depth giving X and Z axis data. By moving the object in the Y-Scan direction the Y-axis data point is provided then giving full X, Y & Z dimensional information.

What applications do 3D laser triangulation solve?
Z-Trak laser profile cameras are GigE Vision compliant permitting it to be used with any image processing software that supports 16 bit acquisition using the GigE Vision protocol. Using 3rd party and open platform software development packages such as Dalsa Sapera Processing 3D, Sherlock 8 3D, Stemmer CVB, GeniCAM tools and MvTec Halcon many applications can be solved.
A partial list of applications is as follows:

Teledyne Dalsa provides free software packages consisting of Sapera Processing with run time licenses and Sherlock 3D. Easy to use demo programs are also included. A few examples using the Sapera source code are as follows:

Full specifications, Data sheets and manual for Teledyne Dalsa Z-Trak can be found HERE.
or request a Quote HERE

Click to contact
Give us some brief idea of your application and we will contact you to
discuss camera options.

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera selection.  With a large portfolio of lenses, cables, NIC card and industrial computers, we can provide a full vision solution!

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

Allied Vision GT/GX cameras affected by ON Semiconductor CCD Sensor discontinuation

The rapid move from CCD image sensors to CMOS has unfortunately accelerated the discontinuation of several popular camera series. While this creates issues for existing products using these cameras, it is not all bad news as CMOS image sensors outperform CCD’s and have lowered overall camera prices.

Allied Vision Prosilica GT and GX camera models using ON Semiconductor (formerly Kodak) KAI series sensors are being affected and going end of life. However, Allied Vision has already moved quickly to support customers affected with the discontinuation by introducing several new models with resolutions from 16.8 to 31.4 Megapixels using IMX367, IMX387 and IMX342 sensors. In many cases, there is not a 100% drop in replacement, but by consulting with an imaging advisor, we can help identify some options.
Contact us with your current model for support and recommendations.

The discontinuation is being forced by ON Semiconductor announcing the discontinuation of its CCD sensors and subsequent closure of its Rochester NY plant. (here is the original announcement) This affects all cameras using these sensors!

What camera models are effected by ON Semiconductors discontinuation?


All ON Semiconductors (previously Kodak) image sensors starting with KAI will be effected. The various image sensor models are listed in the above announcement and the associated Allied Vision’s popular Prosilica GT and GX models effected is listed below.

Allied Vision Prosilica GT & GX models effected are in an immediate discontinuation with last time purchases through 3/2/2020. We are encouraging customers to place orders if they are needing spares for field replacements or have immediate builds upcoming. Pricing has increased already 25% due to immediate sensor increases and will increase again December 15, 2019! Click on your model for a quote prior to more price increases.

For Quotes on Prosilica GT cameras click HERE

For Quotes on Prosilica GX cameras click HERE

1stVision can provide suggestions to aid in the transition of cameras. If you have specific models being used, please use our contact form and complete the model’s used and we will contact you with various options.

Contact us to discuss
camera replacement options

1st Vision’s sales engineers have over 100 years of combined experience to assist in your camera selection.  With a large portfolio of lenses, cables, NIC card and industrial computers, we can provide a full vision solution!

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