Agena 2" Color / Planetary Filter - No. 21 Orange
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Stock count is accurate & shown in real time.
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Contiguous US / Lower 48:
Free shipping applies to orders over $50 using our chosen carrier/method. Faster paid options are available at checkout.
Alaska, Hawaii & US Territories:
Free shipping applies to many—but not all—products. Enter your ZIP code in cart or upon checkout to confirm options and costs.
International:
International orders do not qualify for free shipping. Shipping, duties, brokerage, tariffs, and taxes are the customer’s responsibility. Some items may be restricted due to export, size, or manufacturer limitations.
Color filters can be very useful for enhancing your views of the Moon and the planets. Depending on the atmospheric conditions, the telescope being used, the observer's experience, and the planet being observed or photographed, the advantages of color filters can be anywhere from subtle to dramatic. The right filter can make all the difference between seeing several small craters in the floor of Clavius on the Moon or not; seeing five or six swirls in Jupiter's belts or not; or seeing the inner Crepe Ring of Saturn or not.
Agena's 2" color/planetary filters are manufactured from the purest optical glass and are dyed-in-the-mass (not simply "color coated") for premium performance. They thread into the barrels of virtually any 2" telescope eyepiece. Each filter cell has a male and female 2" filter thread (M48x0.75) on opposite sides, so multiple filters can be stacked to achieve selective filtration of the visual color spectrum. The clear aperture is 43mm and each filter comes in a protective plastic storage case.
The #21 Orange Filter reduces or blocks transmission of blue and green wavelengths. It sharpens boundaries between yellow-orange areas and blue-green regions on Mars, resulting in a darkening of edge-detail in the Maria. Use it on Jupiter and Saturn to sharpen contrast and enhance detail in the belts and polar regions and to bring out the Great Red Spot. The filter also enhances viewing of festoons and polar regions. It will also slightly increase surface details on Saturn, particularly highlighting the bands and blue polar regions. This one behaves very similarly to the #15 but gives slightly more contrast
The filter greatly enhances lunar features. It can be used to reduce sky brightness during daytime observations to improve viewing of Venus and to reveal surface features on Mercury. When used on comets in large telescopes, the orange filter enhances definition of dust tails and comet-heads.
Other Information
- Country of Manufacture: China
Color filters can be very useful for enhancing your views of the Moon and the planets. Depending on the atmospheric conditions, the telescope being used, the observer's experience, and the planet being observed or photographed, the advantages of color filters can be anywhere from subtle to dramatic. The right filter can make all the difference between seeing several small craters in the floor of Clavius on the Moon or not; seeing five or six swirls in Jupiter's belts or not; or seeing the inner Crepe Ring of Saturn or not.
Agena's 2" color/planetary filters are manufactured from the purest optical glass and are dyed-in-the-mass (not simply "color coated") for premium performance. They thread into the barrels of virtually any 2" telescope eyepiece. Each filter cell has a male and female 2" filter thread (M48x0.75) on opposite sides, so multiple filters can be stacked to achieve selective filtration of the visual color spectrum. The clear aperture is 43mm and each filter comes in a protective plastic storage case.
The #21 Orange Filter reduces or blocks transmission of blue and green wavelengths. It sharpens boundaries between yellow-orange areas and blue-green regions on Mars, resulting in a darkening of edge-detail in the Maria. Use it on Jupiter and Saturn to sharpen contrast and enhance detail in the belts and polar regions and to bring out the Great Red Spot. The filter also enhances viewing of festoons and polar regions. It will also slightly increase surface details on Saturn, particularly highlighting the bands and blue polar regions. This one behaves very similarly to the #15 but gives slightly more contrast
The filter greatly enhances lunar features. It can be used to reduce sky brightness during daytime observations to improve viewing of Venus and to reveal surface features on Mercury. When used on comets in large telescopes, the orange filter enhances definition of dust tails and comet-heads.
Color filters can be very useful for enhancing your views of the Moon and the planets. Depending on the atmospheric conditions, the telescope being used, the observer's experience, and the planet being observed or photographed, the advantages of color filters can be anywhere from subtle to dramatic. The right filter can make all the difference between seeing several small craters in the floor of Clavius on the Moon or not; seeing five or six swirls in Jupiter's belts or not; or seeing the inner Crepe Ring of Saturn or not.
Agena's 2" color/planetary filters are manufactured from the purest optical glass and are dyed-in-the-mass (not simply "color coated") for premium performance. They thread into the barrels of virtually any 2" telescope eyepiece. Each filter cell has a male and female 2" filter thread (M48x0.75) on opposite sides, so multiple filters can be stacked to achieve selective filtration of the visual color spectrum. The clear aperture is 43mm and each filter comes in a protective plastic storage case.
The #21 Orange Filter reduces or blocks transmission of blue and green wavelengths. It sharpens boundaries between yellow-orange areas and blue-green regions on Mars, resulting in a darkening of edge-detail in the Maria. Use it on Jupiter and Saturn to sharpen contrast and enhance detail in the belts and polar regions and to bring out the Great Red Spot. The filter also enhances viewing of festoons and polar regions. It will also slightly increase surface details on Saturn, particularly highlighting the bands and blue polar regions. This one behaves very similarly to the #15 but gives slightly more contrast
The filter greatly enhances lunar features. It can be used to reduce sky brightness during daytime observations to improve viewing of Venus and to reveal surface features on Mercury. When used on comets in large telescopes, the orange filter enhances definition of dust tails and comet-heads.
Other Information
- Country of Manufacture: China