focal length

Spot diameters of just a few thousands of an inch can readily be attained with convenient short focal length lenses.

The focal length you need depends on your distance from the burst and what you're trying to capture.

Use angle encoder calibration coefficient of deviation of the long focal length of high-precision tracking system was satisfactory results.

Objective and the focal length of the specimen to be measured. The measurement of the size of the reticle.

To determine power, divide the focal length of the telescope (in mm) by the focal length of the eyepiece (in mm).

The focal length of the condensing lens should be such that the image of the source just fills the projecting lens.

If you know the FOV, sensor size, and working distance, you can compute the focal length of the lens you need using the following formula.

It can be used to really evaluate the optical performance and imaging characters at any focal length of a zoom system.

Using a longer focal length and photographing stars far from the north star increase the distance stars will move across the image.

Or, you can calculate the exit pupil by dividing the focal length of the eyepiece (in mm) by the focal ratio of the telescope.

These actually change the focal length of the lens rather than just magnifying the information that hits the sensor.

The automatic adjustment in the focal length of the lens of the eye to permit retinal FOCUS of images of objects at varying distances.

The more light pass through, the lower F number is. Shown in the following figure, F is the ration of focal length and effective diameter.

Focal length: The distance between the centre of a lens and its principal focus.

The longer the focal length of the telescope, generally the more power it has, the larger the image and the smaller the field of view.

If you know the focal ratio but not the focal length, you can calculate it: focal length is the aperture (in mm) times the focal ratio.

As the lens focal length is critical to capturing sharp images, this study aimed to develop a set of real-time auto-focus search algorithms.

The aperture size (area of the aperture) of a lens could be calculated from focal length and the correspondent f-number.

In taking a picture, the shutter, the focal length and the other things must be adjusted as the case may be .

At present, some difficulties are encountered in measurement of long focal-length of mirrors.

On the basis of thin-lens focal length measurement experiment, the imaging law of refraction-reflection system was further studied.

Zooming optical system is a system in which the focal length can be changed continuously but the image surface position keeps stable.

The software computes the Back focal length from focal plane position and the reference position (as well as the offset, if entered).

Z sitting on the bed, I am smiling camera position, at the lens, the focal length of the well, set up a regular.

One zoom lens can replace several fixed focal-length lensed, but results are likely to be inferior.

The lens is set to its widest focal length (38mm of the 35mm equivalent) and a polarizer is stacked on top of the 28mm UV filter.

The easiest way to get a pleasing background is to use a long focal length and a wide aperture.

Object distance, image distance and focal length are distances, so they cannot be negative.

The focal length was found to be roughly proportional to the radius of the curvature.

Zoom lens A lens whose focal length can be varied continuously over a substantial range.

This is the ratio of the focal length of the telescope to its aperture.

For large aperture lens, scanning method was developed to measure the focal length in different locations within the mirror.

You must first specify the focal length of the telescope and the size of the CCD chip or film negative.

In order to be able to evaluate a large focal length range, different converter lenses must be used.

The scanner's baseline correction including focal length adjustment and brightness, contrast and white balance, color, tuning, etc.

If very expensive, big, and heavy, may be almost as good and almost as fast at any given focal length as cheap fixed primes.

On this basis, we calculated the camera's focal length and target depth information in the calibration test.

It has just the right field of view and focal length to focus on your face at arm's length.

Internal water passages eliminate outside cooling lines on multiple focal length configurations.

After many experiments on the scanner's focal length error which makes up his mind.

Focal point is, the distance between the two is the focus of the focal length.

In the experiment, it realized the control of the variable focal length optical system to hollow laser beams.

Taking photographs of these small deep sky objects require a lens of longer focal length, sometimes a telescope is used instead.

But the focal length becomes inconvenient as a measure of lens power when lenses are combined.

The exact shutter speeds and shape of the curves all depend on you, your surroundings and the focal length.

The results were the following: In such cases the geometric focal length, the larger circular aperture, the longer the focal length.

The first single-curved reflective surface has a focal length greater than that of the second single-curved reflective surface.

Notice the difference in the apparent distance of objects that each focal length produces.

This dissertation aims at meeting the needs of designing long focal length space camera.

Here the combinations of Testcharts and measuring objectives for different focal length ranges are preset.

This curved energy transmission surface defines a focal point (8) and a focal length (9).

This photograph is shot by lens with a long focal length.

The unsteadiness of air becomes prohibitive only if instruments with large focal length are used.

That cone angle is directly controlled by the focal length.

Camera lenses have two general attributes: f-stop and focal length .

Figure 4. Relationship Between Focal Length, FOV, Sensor Size, and Working Distance.

Thermal effect of thin disk laser is analyzed. Thermal focal length expression is carried out theoretically.

Focus : plane of focus ; focal length; and depth of field.

At present researchers work at the analogous optical system, which makes possible to change focal length.

But once you have the focal length determined, everything else is a piece of cake.

Set the focal length on your lens.

For the first shot he used a shorter focal length and the second shot he used a longer one.

Aotou Jing focal length, is the focus of the lens from the center.

Finding #4: If not masked by free hand blur, then the effect is almost independent of focal length.

What is the best focal length for bird photography?

In case we know the focal length, we may determine the position where a clear image may be observed.

Otherwise, set the focal length to infinity so that all distant objects are in focus.

I have found by trial and error that 10mm focal length is close to what we need.

The iPhone camera has a fixed focal length.

The shorter the focal length, the more field of view you can capture.

First, measure some experimental parameters, such as the thermal focal length, the size of the pump laser and so on.

Figure 1. Illustration of undercorrected spherical aberration. The margins of the lens have a shorter focal length than the center.

Smaller sensors 'crop' the scene and make a lens appear to have a longer focal length.

Can I control the focal length?

Two lenses of focal length 10 cm have a combined focal length of 5 cm.

For specific optics (50, 100 mm focal length) there is a constant angular field ( Cos Phi ).

The reason for this is that as we know, longer focal length lenses magnify the image, but they also magnify the camera shake.

The focal length varies from 2851 micrometers to 1712 micrometers , and the response time is about 1. 6 seconds.

but the new mirror assemblies have a shorter focal length than Hubble's, allowing them to study patches of sky around 100 times larger.

The autocollimating telescope method for determination of the radius of curvature and focal length of thin lens

Design and structural analysis for adjustment mechanism of imaging lens's focal length of space solar telescope

The focal length of thin lens derived from the function of complex amplitude transmittance

Research on the Instrument for Measuring the Focal Length of Infrared System Base on the Linear Array CCD

Measurement of thermal focal length of LD-end-pumped crystal under stable-cavity-condition

Determination of thermal focal length of diode laser end-pumped solid-state amplifier

The Analysis of Imaging for Measuring the Focal Length of Convex Lens in Auto-collimation Method

Discussion on the Methods of Coaxal Adjustment of Determining the Focal Length of Thin Lens

Focal length measurement by calculating Fourier transform spectrum interference fringes of symmetric double circular apertures

The Improvement of Image Plate in the Experiment of Determining the Thin Focal Length of Lens

Measuring the focal length of concave lens using collimator

Accurate Measurement and Processing of the Angular Deviation of TV tracking System with Long Focal Length and Continuous Zooming

Measuring the focal length of concave lens using collimator

Dependence of optical limiting characteristics on focal length in stimulated Brillouin scattering

Photography (Optics) - Camera Lenses - Focal Length, Focusing Scale, and Distance Scale Markings

The Problem Existing in Measuring the Focal Length of Thin Lens

A Method for Measuring the Focal Length of Thin Concave Lens

Distortion Correction of Imaging System With a Large-Field Short Focal Length Lens

Manufacturing for ruling concave metal grating with a long focal length

Due to the card plug green type telescope focal length long and JingShen short, magnification is big also, income image is clear;

Fringes thresholding method in the measurement of lens focal length using Moire deflectometer

Fringes thresholding method in the measurement of lens focal length using Moire deflectometer

Fundamental standards for optics - Determination of focal length

photographic lenses - measurement for focal length

Scanning Method for Focal Length Measurement of Large Aperture Long Focal Mirror and Lens

Equivalent Focal Length Estimation Method for Digital Camera

The Study at Automatic Focusing Systems and Methods of Calibrated Focal Length Used in Precision Measurement

Design of long focal length space optical system with three reflective mirrors

Design of the Compact Optical System for Multiple Focal Length

A Camera Calibration Method of Varying Effective Focal Length by Neural Network

Further study on thin-lens focal length measurement experiment

Dynamic Analysis on Lightweight Long Focal Length Space Lens

Two-mirror system with small size, long focal length and no chromatic aberration is used widely in large-scale optical instrument;

Optical Design for the Off Axis Telescope with Long Focal Length and Wide Field of View

Design of long focal length large-aperture optical zoom system

Focal Length Measurement of Infrared Lenses

A New Manufacture Technique for Long Distance Focal Length Lens

Measurement of monochrome focal length based on single-slit fractional Fourier transform

Design of a Short Focal-length Zoom System

The Application of CCD Sensor to Focal Length Measuring

objective with variable focal length

chromatic difference of focal length

Measuring the lens focal length with linear array CCD

Application for Changing Focal Length in the Process of Tracking Measurement

Research on focal length measurement based on digital image processing

Variable Focal Length Zoom Lenses CCTV

Effect of temperature on measuring system of long focal length

Focal Length Markings of Lenses

Active focal length output of zoom lens

lens of variable focal length

Focal length in mm film