Before we explain what a flipout condenser is used for, let's answer the question for this site.  Most of the Olympus and Nikon microscopes we provide at Microscope Marketplace require a flipout condenser to fill the entire field while using a 1.25 or 2X objective.  This is one of the most commonly used objectives for the Pathology market.  It makes scanning the slide quick and effiecent.

Whether you need a flip-out condenser for your 2x objective depends on the specific microscope setup and the type of specimens you are observing. Let's understand the purpose and considerations of using a flip-out condenser with a 2x objective:

1. Purpose of the Condenser: The condenser is a crucial component of a microscope that helps focus and direct light from the light source onto the specimen. It plays a significant role in determining the quality of the image, particularly at higher magnifications.

2. Condenser Numerical Aperture (NA): The numerical aperture of the condenser should match or exceed the numerical aperture of the objective to ensure optimal illumination and resolution. The NA of the condenser determines the cone of light entering the objective, which affects the resolution and brightness of the image.

3. Flip-Out Condenser: Some microscopes have flip-out condensers, which can be moved in and out of the optical pathway. These condensers are designed to be used with objectives of different magnifications. When using lower magnification objectives like the 2x, you might need to flip the condenser out of the way to achieve the best image quality and avoid potential over-illumination issues.

4. Light Control: The use of a condenser can help control the intensity and distribution of light on the specimen. For some specimens and objectives, too much or too little light can affect the image quality, contrast, and depth of field. Adjusting the position of the condenser can help optimize the illumination for your specific application.

5. Specimen Type: The type of specimen you are observing can also influence the need for a condenser. Transparent specimens, for example, may benefit from the use of a condenser to improve contrast and resolution.

In the case of a 2x objective, which is a low magnification objective, the need for a flip-out condenser might depend on the specific microscope's design and the illumination setup. Some microscopes with built-in condensers are optimized for lower magnification objectives, and you may not need to use a flip-out condenser for the 2x objective.  

However, if your microscope has a flip-out condenser, it's a good idea to experiment with both positions (in and out) to observe how it affects the image quality. Observe the specimen with and without the condenser, and choose the setup that provides the best contrast, resolution, and overall image quality for your specific specimens and applications.

Always consult your microscope's user manual or seek advice from experienced microscopy users to understand the best setup and configuration for your microscope and objectives. Proper illumination and condenser use can significantly impact the quality and accuracy of your microscopy observations.