Telecentric Barlow lens SkyWatcher NOMAD 5x (4 elements) 1,25"

SkyWatcher Nomad 5x Telecentric Barlow Lens (4 elements) 1.25"

The Sky-Watcher Nomad 5x Telecentric Barlow lens does not act exactly like a conventional Barlow lens. It multiplies the focal length by 5 but, instead of diverging like a conventional Barlow lens, an additional optical group forces the outgoing light rays to remain parallel to the optical axis; the exit pupil is pushed back to infinity.

This device has a number of advantages. The ocular space (or eye relief) of the eyepiece with which it is associated is not altered. The magnification ratio remains the same, whatever the distance behind the multiplier. There is no parallax effect, since the outgoing rays are parallel to the incoming ones. Finally, this parallelism optimizes the efficiency of interference filters, in particular the Fabry-Pérot patterns used in H-alpha solar filters, where the incident rays must be rigorously parallel to avoid bandwidth drift.

The Nomad 5 is composed of 4 multi-coated lenses, the edges of which have been blackened to reduce parasitic reflections. All mechanical surfaces and threads are painted matte black. The input interface is 1.25" (31.75 mm). It is equipped with an M28.5 female thread for mounting a 1.25" (31.75 mm) flow filter.

This telecentric Barlow lens is especially suitable for high-resolution imaging of the Moon, planets and Sun. It is supplied with all necessary adapters: a 1.25" (31.75 mm) flux filter eyepiece holder for visual use, an M42x0.75 photo adapter for use with a CCD or CMOS camera, and a short M42x0.75 photo adapter for mounting on a digital camera.

IMPORTANT Imaging the Sun requires specialized equipment that is not supplied. You will also need a full aperture solar filter to take your solar photos safely. Please contact us if you need one.

Visual setup

The Nomad 5 can be used with a conventional 31.75 mm eyepiece. However, observation is complicated because its magnification ratio is very high: it is 5 times the magnification of the eyepiece with which it is associated. It is therefore important to calculate the resulting magnifications well and to combine Nomad 5 with the right eyepiece if you do not want to obtain exaggerated and unusable magnifications on your instrument.

We recommend that you use Nomad 5 with long focal length eyepieces or mount it on short focal length optical tubes.

Mounting on a CCD/CMOS camera

The Nomad 5x telecentric Barlow lens is designed primarily for photography, and more specifically for high-resolution imaging of planets, the Moon and the Sun, where uncooled CMOS cameras are most commonly used. The extender comes with a special adapter for this purpose. It allows direct attachment of cameras with T-thread (M42x0.75 female).

Mounting on a digital camera

The Nomad 5 can be mounted on a digital camera using the supplied short adapter (M42x0.75 male thread). However, you will also need to purchase a standard T-ring, whose mechanical output will be specific to the mount type of your camera (Nikon F, Canon EF, Canon RF, etc.). The T-ring is not supplied.

TECHNICAL SPECIFICATIONS:

• Number of lenses 4
• Multiplication factor 5x
• Mechanical input 1.25" (31.75 mm)
• Mechanical outlets M42x0.75 male flux + 1.25" (31.75 mm) female flux
• Length (extender only) 62 mm
• Diameter (extender only) 39 mm
• Weight (extender only) 90 g

Components supplied with the Sky-Watcher Nomad 5x telecentric Barlow lens

1 x 5x telecentric Barlow lens Sky-Watcher Nomad

1 x visual adapter (1.25" female eyepiece holder)

1 x CMOS/CCD camera adapter (M42x0.75 male)

1 x digital camera adapter (M42x0.75 male)

SkyWatcher 5x (4 element) 1.25" Telecentric Barlow Lens SkyWatcher 5x (4 elements)