Altair 1.25 inch Mini Solar Herschel Wedge (imaging ready)

Altair Solar Wedge 2024 Eclipse Version for refractors. The Altair Solar Wedge (Herschel Wedge) replaces the normal 1.25" diagonal mirror on your refractor telescope. The Solar Wedge transmits a greatly reduced, safe amount of light to the eyepiece or camera.

Please note this product is designed to be used with REFRACTORS ONLY, and is not intended for use with reflector telescopes.

Altair 1.25" Solar Wedge Features: 

• 1.25" Push-fit adaptor.
• Ceramic Diffuser on the rear helps alignment and controls heat, enabling use with up to 5" refractors all day long without overheating.
• T-Thread on top of the push-fit adaptor lets you screw a Magnetic Filter Holder or Hypercam directly onto the Solar Wedge, to hold Altair contrast filters such as G-Band or Altair 540nm, Altair NUV, CaK.
• Unlike other makes, the Altair Solar Wedge enables both visual and imaging applications without having to change internal filters to adjust brightness. The top section can be turned to adjust the brightness level, to suit your accessories or camera.
• Light path is 100mm and weight is only 185g.

Altair Solar Wedge is "imaging ready" because you can fine-tune the image brightness without removing your camera to get the best exposure, gain and contrast settings. That's ideal for "lucky imaging" CMOS cameras such as Altair Hypercam or GPCAM series. Use of filters such as Altair G-Band, Altair 540nm Continuum, and Altair NUV filter is made easier due to the brightness control.

Solar wedges are well known to give a sharper, higher-contrast image than traditional front-mounted metallized solar film. This is achieved by eliminating reflections between the filter and telescope lens. The result is a sharper, extremely high contrast view of sun spots, including solar photosphere features such as granulation. Sun spot centres appear a much darker black compared to views with solar film filters and many customers report never having seen the finer structures before. The difference is quite remarkable and immediately visible in the eyepiece. The Altair Solar Wedge has special anti-reflection coatings on the internal polarising filter and prism. A high specification prism gives the ultimate in sharpness and resolution for imaging and observing.

Safe and easy to use: Cheaper solar wedges direct excess energy downwards into the ground, or worse, heat up a block of metal on the back which you can burn yourself with. The Altair Imaging-Ready Solar Wedge directs energy into a special extra thick Polycrystalline Ceramic Diffuser disc at the back of the Wedge. Air vents allow air circulation by convection. The Polycrystalline disc has the added benefit of being translucent to some degree - therefore acting as a kind of narrow-field "solar finder". It doesn't completely replace the Altair Solar Finder, however works in tandem with it, enabling final tweaks even with a high power eyepiece installed. The sun appears projected onto the back of the diffuser as a "ball of light". Simply move your telescope until the ball of light is in the centre of the diffuser disc, and you are aligned with the sun, even with a high power eyepiece!

One wedge does it all! Both solar photography or visual observation: Often solar wedges don't give enough light for high speed exposures needed to "freeze" air-motion for a sharp image. The Altair Solar Wedge has an AR coated internal polarising filter, which let's you control the brightness of the image. Brightness can be increased or decreased by rotating the top turret assembly, then locking it in the desired position a thumbscrew. Variable brightness is very important both for visual and imaging use, to fine tune the ideal exposure time, or the ideal contrast levels at the eyepiece - especially when adding a colour filter such as the Altair 540nm continuum filter, or G-Band filter for extra contrast. Unlike other makes, the Altair Solar Wedge enables both visual and imaging applications without having to change internal filters. With the solar wedge in "bright" mode, exposure times as low as 2 milliseconds are routinely possible with high speed CMOS cameras like the Altair Hypercam or GPCAM. This effectively "freezes" the seeing (air movement), resulting in an incredibly sharp image.

Altair Solar Wedge Questions and answers:

Q: How do I observe the sun safely with a telescope and filter or Solar Wedge? If you view the sun through a telescope or binoculars without a professional filter product, immediate and permanent eye damage will result. This has discouraged people from exploring this fascinating subject, however observing the sun is perfectly safe, provided you use your filter equipment correctly. Each wedge ships with instructions which must be read and understood completely before using the product. Never allow children to observe the sun with a telescope and wedge or filter without the supervision of a competent adult. Never remove a solar filter or wedge without first placing the front lens cap on the telescope. Always securely fasten solar filters or Solar Wedge securely to the telescope. Always remove any optical finder from the telescope before pointing it at the sun, because you could inadvertently look through it. We recommend using the safe Altair solar finder with any solar filters or Wedge. Code: SOLARFINDER). 

Q: What telescopes can I use with a Solar Herschel Wedge? A: Only refracting telescopes up to 6" (152mm) aperture can be used with the Altair Herschel Solar Wedge. Refracting telescopes have a front lens, and do not have any mirrors. It is dangerous to use ANY telescope with mirrors with a Herschel Solar Wedge. This includes Maksutov Cassegrains, Schmidt Cassegrains, Newtonians and Ritchey Chretiens, amongst others. If in doubt, contact Altair Astro or your authorized dealer.

Q: Can I use coloured filters with the Altair Solar Wedge? A: Yes but only if positioned AFTER the wedge. NEVER add ANY filter in front of a Solar Wedge, because it will crack or melt due to the concentrated heat from the sun, and it can deposit metal vapour on the rear of the objective lens. Never position a filter, Barlow lens, or flattener/reducer in front of the wedge.

Q: How do I "tune" the image brightness for “lucky” imaging? A: Being designed for visual or imaging use, the internal polariser module (controlled by rotating the turret top) has a wider brightness range than normal Hershel wedges, allowing for fast frame rates and short exposure durations suitable for “lucky imaging”. When imaging the sun using "lucky" imaging techniques with a high frame rate camera like the Altair Hypercam, it's best to keep the exposure duration of the camera as short as possible - ideally under 15 milliseconds is ideal for apertures up to 100mm and faster for for large apertures. This "freezes" air motion to show granulation and other small details. When set for fast frame rates, the image can appear very bright visually through an eyepiece, like looking at a light bulb. This is uncomfortable, but not dangerous due to the protective ND filter inside the unit. CMOS cameras can be used at full brightness. If using the wedge for imaging only, you can just insert the camera and turn the turret-top until you are satisfied with the exposure duration and gain settings. If you are using the Altair G-Band, NUV or CaK filters it’s recommended to image at maximum brightness.

Q: For how long can you keep the 1.25” Mini Solar wedge aimed at the sun?  The Altair 1.25” Mini Solar Wedge has been fully tested with the sun remaining in the centre of the field of view for 4 hours of continual use centred on the sun with a 152mm aperture refractor telescope in mid-summer from 11:00 – 14:00, and a cloudless sky. At no point did the outer prism housing become too hot to touch, a common problem with cheaper solar wedges. Whilst we cannot recommend use with telescopes of larger than 152mm aperture for longer or shorter durations, if your telescope is larger than 6”, then we suggest trying the wedge for a shorter time, to assess the heat build-up, and then make your own informed decision.

Q: What if I drop or disassemble the product? Do not use the product unless it’s in perfect condition. Always first contact Altair technical support.

Q: What filters can be used behind the solar wedge? Altair G-Band, Altair 540nm, Altair CaK and Altair NUV filters can all be used behind the wedge to increase contrast and highlight various solar features.

Note: Altair Astro and resellers reserve the right to change product specification and price without notice.