Baader SunDancer II Telecentric Lens System
Ships by Next Business Day
Contiguous US Customers:
All items we sell ship for free within the Contiguous US. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. During checkout, you may also be shown other optional faster shipping choices.
US Customers in Hawaii and Alaska:
Free shipping applies to almost all products. A few large telescopes and mounts are excluded from this free shipping offer. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.
International Customers:
Free shipping does not apply to international orders. During check-out, you will be presented with several shipping choices and costs. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions.
- Delivers a plane-parallel, achromatic beam of light with 36 mm diameter
- Designed especially for H-alpha and CaK subangstroem etalon filters
- Includes a ½" filter cell for the 2 nm block filter of the Baader SunDancer II H-alpha filter
- Can also be used in place of a Barlow lens, expands the telescope focal length by 4x
- BBAR (Broad-Band Anti-Reflection) coating
- Anti-reflective thread and blackened lens edges against reflections and for maximum contrast
- Image circle 36 mm, in a nominal in 97 mm from base of the T-2 thread
- 1¼" and 2" nosepiece with 1¼" filter thread, T-2 thread on camera side
- 12.5 mm (1/2") filter exchange tool included
- 5-year warranty if handled properly
Baader SunDancer II 4x Telecentric System TZ-4S
Telecentric systems are mainly used in H-alpha filters for solar observation, where the 1/100 lambda plane-parallel etalon in the H-alpha filter requires a perfectly parallel beam of light over the entire image. These telecentric systems deliver very sharp images, but are usually only optimised for the H-alpha wavelength.
This achromatic SunDancer 4x telecentric is designed for the entire visible spectrum and can therefore not only be used on H-alpha systems, but the TZ-4S, as well as the Baader SunDancer II Telecentric System TZ-3S ( # 1363070) can also be used instead of a Barlow lens. Due to the parallel beam of light, it is very good-natured with regard to the working distance: While the magnification factor of a Barlow lens changes with the distance to eyepiece or camera (zoom eyepieces are also based on this principle), the magnification factor and image quality of the TZ-4 do not change, even if the camera or eyepiece is mounted well behind the nominal working distance (97 mm from the base of the T-2-thread).
The achromatic SunDancer II TZ-4S illuminates an image circle of 36 mm at a distance of 97 mm from the base of ther T-2-thread. The contrast is better than with the common methods used for higher magnifications: simple barlow lenses or eyepiece projection. With the 4x telecentric system, high magnifications for observing the solar system can be achieved even with long focal length orthoscopic eyepieces. The eye relief of the eyepieces used does not change, too! The focus position changes only 3 mm outward when using the 2" nosepiece of the telecentric, compared to a 2" eyepiece.
The connection on the telescope side is made via a dual 1.25"/2" nosepiece with safety kerfs (these prevent tilting due to an incorrectly positioned safety groove and at the same time provide a secure hold). On the camera side, the T-2 thread provides a tilt-proof, fixed connection even to heavy cameras or to T-2 eyepiece clamps. For the T-2 thread, adapter rings are available for almost all common connection systems (e.g. M48 / 2"/ M68).
The TZ-4S in use with H-alpha-Filters
The TZ-4S was specially designed for the Baader SunDancer II H-alpha Filter (# 1363056) and replaces the original 3x telecentric. This allows to use the SunDancer II H-alpha filter also on telescopes with f/7-f/8 with the optimal focal ratio of about f/30.
Please note: For this, the 12 mm 2 nm H-alpha blocking filter, which is pre-installed in the front of the TZ-3S, must be installed in the TZ-4S. This blocking filter is not available separately. The ideal working distance when using the SunDancer II is then 70 mm from the base of the T-2 thread of the SunDancer II H-alpha filter (instead of 65 mm with the original TZ-3S).
For H-alpha filters with up to 36 mm diameter with their own block and energy protection filter (e.g. SolarSpectrum filter), the TZ-4S can be used instead of the long-building Telecentric System TZ-4 (4x focal length) (# 2459256) .
The SunDancer II Telecentrics
Baader SunDancer II Telecentric System TZ-4S (# 1363080) with violet anodized label: Achromatic 4x telecentric with 97 mm working distance from the base of the T-2 thread and 36mm clear aperture. Provides the desired focal ratio of f/30 on telescopes with f/7.5. For clear identification, this telecentric has a violet anodized label. This telecentric does not include the 2 nm blocking filter of the H-alpha filter; for use with the SunDancer II, the 2 nm block filter must be converted from the TZ-3S of the SunDancer II filter to the TZ-4S. The use with large SolarSpectrum H-alpha filters with already integrated block filter and additional energy protection filter is possible without this additional 2 nm block filter.
The blocking filter reflects the sunlight just before the etalon and the telecentric system. This protects the etalon from excessive heat. In addition, an etalon also transmits wavelengths that are a multiple of the desired transmission line; these are also stopped by the blocking filter, too. The blocking filter or the TZ-3S with pre-installed blocking filter are not available separately.
Important Note:
TZ-optical systems are essential for undeteriorated performance of heated SolarSpectrum filters:Please note that for H-alpha observations below 1 Ang halfbandwidth (FWHM) a telecentric lens system is absolutely mandatory, in order to achieve the recommended focal ratio of f/30 to (preferably) f/40! Because only with a telecentric approach you can create a perfectly parallel optical path which is essential for the unrestricted function of such a complicated etalon.
A TZ-lens-system is an ESSENTIAL prerequisite. One could also bring a telescope to a focal ratio of f/30, but this does not mean at all that a parallel optical path is created. And mind you, a still slightly conical optical path with f/30 sent into an etalon with 0.5 Ang FWHM would only provide the contrast as if the filter had a FWHM of 0.7 Ang or much worse.
The main difference between TZ-4S and the older TZ-4 are adaptation to the telescope ( the TZ-4 uses T-2-threads for a stable connection – perfect for the long SolarSpectrum filters) and their working distance. The free apertureof the TZ-4S is comparable with about 35 mm and does not fully illuminate the largest SolarSpectrum filters with 46 mm filter diameter. But it doesn't always have to be a TZ-4. The 2" Research Grade TZ-3 Telecentric System (3x focal length) ( #2459257-) with 46mm clear aperture is much better in terms of optical calculation than the 20 year older TZ-4. So it makes sense for the user to start with a TZ-3 RG and rather stop down the telescope aperture to get to f/30. This will bring out the real contrast of the chosen SolarSpectrum-filter much better than with a poorly matched system where, for example, the older TZ-4 has a smaller clear aperture than the Solar Spectrum-Etalon would require. In the long run, a recalculated, large RG TZ-4 is in preparation - it is worth to wait for it and to get familiar with H-alpha observation with the TZ-3 first. Later, one will surely need both systems (RG-TZ-3 and RG-TZ-4) and will have to stop down the telescope aperture as needed.
Only AFTER the H-alpha etalon you can extend the field size by reducing the f-ratio with adding the new ResearchGrade telecompressor 0.4 into the optical train.
Basically - a Barlow lens has no place in an H-alpha system!
Specifications:
- Manufcaturer: Baader Planetarium
- EAN Code: 4047825052124
- SKU (#): 1363080
- Outer Connection (Lens sided): ø 1¼" (31.75 mm), ø 2" (50.8mm)
- Outer Connection (Eyepiece/Camera-sided): M42 x 0.75 (T-2)
- Image Field: 36mm
- Focal Length Extension: 4x
- Inner Diameter / Clear Aperture: 36mm
- Usage: for H-alpha observation with SolarSpectrum filters
- Backfocus: 97 mm from the bottom of the T-2 thread (When used with Baader SunDancer II H-alpha filter: 70 mm from the bottom of the T-2 thread of the H-alpha filter)
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
- Delivers a plane-parallel, achromatic beam of light with 36 mm diameter
- Designed especially for H-alpha and CaK subangstroem etalon filters
- Includes a ½" filter cell for the 2 nm block filter of the Baader SunDancer II H-alpha filter
- Can also be used in place of a Barlow lens, expands the telescope focal length by 4x
- BBAR (Broad-Band Anti-Reflection) coating
- Anti-reflective thread and blackened lens edges against reflections and for maximum contrast
- Image circle 36 mm, in a nominal in 97 mm from base of the T-2 thread
- 1¼" and 2" nosepiece with 1¼" filter thread, T-2 thread on camera side
- 12.5 mm (1/2") filter exchange tool included
- 5-year warranty if handled properly
Baader SunDancer II 4x Telecentric System TZ-4S
Telecentric systems are mainly used in H-alpha filters for solar observation, where the 1/100 lambda plane-parallel etalon in the H-alpha filter requires a perfectly parallel beam of light over the entire image. These telecentric systems deliver very sharp images, but are usually only optimised for the H-alpha wavelength.
This achromatic SunDancer 4x telecentric is designed for the entire visible spectrum and can therefore not only be used on H-alpha systems, but the TZ-4S, as well as the Baader SunDancer II Telecentric System TZ-3S ( # 1363070) can also be used instead of a Barlow lens. Due to the parallel beam of light, it is very good-natured with regard to the working distance: While the magnification factor of a Barlow lens changes with the distance to eyepiece or camera (zoom eyepieces are also based on this principle), the magnification factor and image quality of the TZ-4 do not change, even if the camera or eyepiece is mounted well behind the nominal working distance (97 mm from the base of the T-2-thread).
The achromatic SunDancer II TZ-4S illuminates an image circle of 36 mm at a distance of 97 mm from the base of ther T-2-thread. The contrast is better than with the common methods used for higher magnifications: simple barlow lenses or eyepiece projection. With the 4x telecentric system, high magnifications for observing the solar system can be achieved even with long focal length orthoscopic eyepieces. The eye relief of the eyepieces used does not change, too! The focus position changes only 3 mm outward when using the 2" nosepiece of the telecentric, compared to a 2" eyepiece.
The connection on the telescope side is made via a dual 1.25"/2" nosepiece with safety kerfs (these prevent tilting due to an incorrectly positioned safety groove and at the same time provide a secure hold). On the camera side, the T-2 thread provides a tilt-proof, fixed connection even to heavy cameras or to T-2 eyepiece clamps. For the T-2 thread, adapter rings are available for almost all common connection systems (e.g. M48 / 2"/ M68).
The TZ-4S in use with H-alpha-Filters
The TZ-4S was specially designed for the Baader SunDancer II H-alpha Filter (# 1363056) and replaces the original 3x telecentric. This allows to use the SunDancer II H-alpha filter also on telescopes with f/7-f/8 with the optimal focal ratio of about f/30.
Please note: For this, the 12 mm 2 nm H-alpha blocking filter, which is pre-installed in the front of the TZ-3S, must be installed in the TZ-4S. This blocking filter is not available separately. The ideal working distance when using the SunDancer II is then 70 mm from the base of the T-2 thread of the SunDancer II H-alpha filter (instead of 65 mm with the original TZ-3S).
For H-alpha filters with up to 36 mm diameter with their own block and energy protection filter (e.g. SolarSpectrum filter), the TZ-4S can be used instead of the long-building Telecentric System TZ-4 (4x focal length) (# 2459256) .
The SunDancer II Telecentrics
Baader SunDancer II Telecentric System TZ-4S (# 1363080) with violet anodized label: Achromatic 4x telecentric with 97 mm working distance from the base of the T-2 thread and 36mm clear aperture. Provides the desired focal ratio of f/30 on telescopes with f/7.5. For clear identification, this telecentric has a violet anodized label. This telecentric does not include the 2 nm blocking filter of the H-alpha filter; for use with the SunDancer II, the 2 nm block filter must be converted from the TZ-3S of the SunDancer II filter to the TZ-4S. The use with large SolarSpectrum H-alpha filters with already integrated block filter and additional energy protection filter is possible without this additional 2 nm block filter.
The blocking filter reflects the sunlight just before the etalon and the telecentric system. This protects the etalon from excessive heat. In addition, an etalon also transmits wavelengths that are a multiple of the desired transmission line; these are also stopped by the blocking filter, too. The blocking filter or the TZ-3S with pre-installed blocking filter are not available separately.
Important Note:
TZ-optical systems are essential for undeteriorated performance of heated SolarSpectrum filters:Please note that for H-alpha observations below 1 Ang halfbandwidth (FWHM) a telecentric lens system is absolutely mandatory, in order to achieve the recommended focal ratio of f/30 to (preferably) f/40! Because only with a telecentric approach you can create a perfectly parallel optical path which is essential for the unrestricted function of such a complicated etalon.
A TZ-lens-system is an ESSENTIAL prerequisite. One could also bring a telescope to a focal ratio of f/30, but this does not mean at all that a parallel optical path is created. And mind you, a still slightly conical optical path with f/30 sent into an etalon with 0.5 Ang FWHM would only provide the contrast as if the filter had a FWHM of 0.7 Ang or much worse.
The main difference between TZ-4S and the older TZ-4 are adaptation to the telescope ( the TZ-4 uses T-2-threads for a stable connection – perfect for the long SolarSpectrum filters) and their working distance. The free apertureof the TZ-4S is comparable with about 35 mm and does not fully illuminate the largest SolarSpectrum filters with 46 mm filter diameter. But it doesn't always have to be a TZ-4. The 2" Research Grade TZ-3 Telecentric System (3x focal length) ( #2459257-) with 46mm clear aperture is much better in terms of optical calculation than the 20 year older TZ-4. So it makes sense for the user to start with a TZ-3 RG and rather stop down the telescope aperture to get to f/30. This will bring out the real contrast of the chosen SolarSpectrum-filter much better than with a poorly matched system where, for example, the older TZ-4 has a smaller clear aperture than the Solar Spectrum-Etalon would require. In the long run, a recalculated, large RG TZ-4 is in preparation - it is worth to wait for it and to get familiar with H-alpha observation with the TZ-3 first. Later, one will surely need both systems (RG-TZ-3 and RG-TZ-4) and will have to stop down the telescope aperture as needed.
Only AFTER the H-alpha etalon you can extend the field size by reducing the f-ratio with adding the new ResearchGrade telecompressor 0.4 into the optical train.
Basically - a Barlow lens has no place in an H-alpha system!
Specifications:
- Manufcaturer: Baader Planetarium
- EAN Code: 4047825052124
- SKU (#): 1363080
- Outer Connection (Lens sided): ø 1¼" (31.75 mm), ø 2" (50.8mm)
- Outer Connection (Eyepiece/Camera-sided): M42 x 0.75 (T-2)
- Image Field: 36mm
- Focal Length Extension: 4x
- Inner Diameter / Clear Aperture: 36mm
- Usage: for H-alpha observation with SolarSpectrum filters
- Backfocus: 97 mm from the bottom of the T-2 thread (When used with Baader SunDancer II H-alpha filter: 70 mm from the bottom of the T-2 thread of the H-alpha filter)
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Baader SunDancer II Telecentric Lens System # TZ-4S 1363080