VideoLabs FlexCam iCam Technical Information download pdf (Page 29)

scope eyepiece. Many commercially-available digital cameras for general use have

autofocus facilities and cannot be focussed on infinity manually. Their front lenses

also cannot be removed, so these cameras tend not to be ideal in use with micro-

scopes. Passable images can be displayed, but expertise is required to obtain the

best-quality images. However, models of camera designed for use in schools with

microscopes are more likely to have removable lenses.

Adapter

(spacer)

Lens set on infinity

Focus image in normal way

In addition to the general criteria to consider (see section 16.6.2), it might be

necessary to add a compensating eyepiece. It is also important to ensure that the

eyepiece lens and the camera lens are the same size, to avoid an outer black ring

around the displayed image (vignetting). This is not an issue if the eyepiece is

removed, as is done when using some cameras.

The prices of digital cameras are still falling; it may be possible to purchase a

good-quality camera for the price of an inexpensive microscope. A resolution of at

least 1.3 Megapixels is preferable for good-quality images and work involving high

magnifications.

Microscope

adaptors

These are tubes with different diameters at either end, one to connect to a camera

or fit over a camera / flexcam lens, the other into or over the microscope eyepiece.

Most flexcams, and other cameras designed for use with microscopes, are supplied

with at least one adaptor but these are available separately and in various sizes to

fit different microscopes. There are two types:

• a simple tube, the purpose of which is merely to align the camera with the

microscope eyepiece;

• an optical tube with a lens to replace the microscope eyepiece.

If possible, users should experiment with both to decide which gives better results;

factors are the flatness of the image, colour aberrations and whether it fills the

screen.

Whatever adaptor is used, it should provide a rigid attachment to the microscope.

Good alignment of the adaptor is important for image quality. If there is too much

movement, wide elastic bands may help by increasing the effective diameter of the

microscope eyepiece tube. If workshop facilities are available, a d-i-y adaptor could

be made to fit a particular microscope, though see the notes under Safe mounting

of the camera in section 16.6.2.

Illumination

Different camera models vary in their light sensitivity. Some have automatic

brightness and colour-balance control; a few flexcams have independent illumina-

tion kits. Some adjustments to the microscope illumination and capture software

might be needed for the best results. However, as always in science, it is worth

experimenting.

Controls

Buttons to adjust brightness or to take snapshots are provided on some cameras;

in some models these controls are accessed via the software. Care might be needed

to avoid disturbing the focus of a microscope while using controls mounted on the

head of a camera. Using a remote-control facility, if provided, avoids this problem.

1 2 ... 24 25 26 27 28 29 30 31 32 33 34 ... 57 58

Comments to this Manuals

No comments

VideoLabs FlexCam iCam Technical Information Page 29

Comments to this Manuals

Related products and manuals for Security cameras VideoLabs FlexCam iCam