Barlow lenses
E95782
Barlow lenses are optical accessories used in telescopes to effectively increase focal length and magnification by diverging the light path before it reaches the eyepiece.
Aliases (2)
- Barlow lens ×48
- Peter Barlow ×3
Statements (51)
| Predicate | Object |
|---|---|
| instanceOf |
diverging lens
→
optical accessory → person → telescope accessory → |
| alters |
light path before it reaches the eyepiece
→
|
| canBePlaced |
in front of a camera adapter for astrophotography
→
|
| canBeUsedWith |
double star observing
→
lunar imaging → planetary imaging → solar observing with proper solar filters → visual observing → |
| compatibleWith |
catadioptric telescopes
→
reflecting telescopes → refracting telescopes → |
| differsFrom |
telecompressor (focal reducer)
→
|
| hasAdvantage |
can improve edge performance of some eyepieces
→
reduces need to buy many short focal length eyepieces → |
| hasComponent |
eyepiece holder
→
lens barrel → negative lens group at the front → telescope-side barrel → |
| hasDisadvantage |
adds more glass elements in the optical path
→
can introduce vignetting with some eyepieces → can magnify optical aberrations of the telescope or eyepiece → can reduce image brightness at high magnifications → |
| hasEffect |
allows use of longer focal length eyepieces to achieve high magnification
→
increases effective focal ratio (f-number) of the telescope → increases eye relief for many eyepieces → reduces field of view for a given eyepiece → spreads light over a larger image scale → |
| hasOpticalDesign |
negative (diverging) lens group
→
|
| historicalPeriod |
19th century origin
→
|
| mayInclude |
compression ring eyepiece clamp
→
filter threads → removable lens cell → |
| mountStandard |
1.25-inch barrel
→
2-inch barrel → |
| namedAfter |
Peter Barlow
NERFINISHED
→
|
| occupation |
mathematician
→
physicist → |
| placed |
between telescope focuser and eyepiece
→
|
| relatedTo |
telecentric amplifier
→
|
| typicalMagnificationFactor |
1.5x
→
2x → 3x → 5x → |
| usedBy |
amateur astronomers
→
professional astronomers → |
| usedFor |
increasing effective focal length of a telescope
→
increasing magnification of a telescope-eyepiece combination → |
| usedIn |
telescope
→
|
Referenced by (1)
| Subject (surface form when different) | Predicate |
|---|---|
|
Cassegrain focus
→
|
usedWith |