TeleVue Big Barlow 2" 2x - Barlow Lens

TeleVue Big Barlow 2″ 2x : Barlowlens: barlowlens van TeleVue

The TeleVue Big Barlow doubles the magnification of 2-inch eyepieces, making it the partner for large Naglers and Panoptics. With the included adapter, it also works with 1.25-inch eyepieces.

This is how a 31 mm Nagler becomes an effective 15.5 mm with the exact same field stop: the same patch of sky, imaged twice as large.

What a good Barlow does

A Barlow lens extends the effective focal length of your telescope, thereby increasing the magnification of any eyepiece inserted into it. Two eyepieces plus a Barlow lens thus cover four magnifications.

The quality of the glass determines whether you get it for free or pay for it with contrast. TeleVue uses high-refraction glass with multiple coatings; the difference with the eyepiece alone is not visible in practice.

Effect on eye distance

A classic Barlow lens slightly increases the eye relief of short eyepieces. This is welcome with a Plössl: a 15mm with a Barlow has more comfortable eye relief than a standalone 7.5mm.

If you want a magnification factor that has no effect on the eye relief or exit pupil, the telecentric Powermate is the alternative within the merk series.

Featured accessories

Combine the Barlow with the TeleVue Ploessls for a compact set that covers four magnifications. The eyepieces are parfocal, so switching requires minimal refocusing.

For whom yes and for whom no

• ✓ Owners of 2 inch eyepieces
• ✓ Anyone who wants to use a field eyepiece as a medium-power eyepiece as well
• ✓ Large Dobsons
• If you only have 1.25-inch eyepieces, the small 2x will suffice
• ✗ Remote photography, see the Powermate 2x

Specifications

More eyepieces and Barlows are on the Accessory page for eyepieces and Barlows. You can find the complete selection of this merk on the TeleVue merk Page.