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I have bought this filter but not yet tried it. Soon I will do imaging of the sun with my Celestron Neximage 5 + APO 2x Barlow and my OTA, Celestron C8" XLT.
I have also bought your AstroSolar Safety Film and will use it in front of the C8".
Is this enough for imaging of the sun or will it be too warm and harm my equipment?
Friends of mine have said that it is also needed to add an extra IR filter to reduce the heat, but this is something I haven't read from you in Baader. Maybe it's some amateur's ideas without the correct knowledge.
I have bought many things from you and think you are one of the best optic manufacturers in the world. I really trust your skills and your products.
So before I start imaging the sun, it's better to ask you for good advice instead of destroying my equipment. :-)
Regards,
Bo Sundin aus Schweden
I have also bought your AstroSolar Safety Film and will use it in front of the C8".
Is this enough for imaging of the sun or will it be too warm and harm my equipment?
Friends of mine have said that it is also needed to add an extra IR filter to reduce the heat, but this is something I haven't read from you in Baader. Maybe it's some amateur's ideas without the correct knowledge.
I have bought many things from you and think you are one of the best optic manufacturers in the world. I really trust your skills and your products.
So before I start imaging the sun, it's better to ask you for good advice instead of destroying my equipment. :-)
Regards,
Bo Sundin aus Schweden
Question by: Bo Sundin on May 12, 2021 11:51:00 AM | 1 Answer(s)
- Description
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Details
Baader Narrowband Filers in sizes 1¼", 2", 50.4mm and 50x50mmDouble Stacked Solar Continuum Filter - For Visual and Photographic Observations of the Sun
Ensures highest contrast in the photosphere of the sun. The filter works as a monochrometer - suppressing the effects of the atmospheric turbulence and results in images that are significantly sharper. Owners of SCTs and refractors will benefit as red and blue wavelengths are completely excluded, with the transmission area peaking at 535nm where telescope optics are sharpest and free from chromatic aberrations.
Important Information for Solar Observing
The Solar Continuum Filter may be used for purely VISUAL observation ONLY in conjunction with the Baader Herschel Prism or with the Baader AstroSolar Safety Film (ND 5.0).
The combination of AstroSolar Photo Film (ND 3.8) and Solar Continuum filter is used exclusively for photography of the sun at high magnifications. This combination is highly apt to capture the finest solar surface detail and granulation at extremely high magnification while enabling ultra-short exposure (measured in milliseconds) in order to freeze atmospheric turbulence.
Customer Examples:
Three sample images, taken by Olivier Grattepanche. Mr Grattenpanche writes:
Instrument: "TSC 225 Schmidt-Cassegrain from TAKAHASHI, NJP160 mount, F/40 with 2X Big Barlow Tele-vue, NGFs focuser, and of course your incredible Baader Astrosolar filter D:3.8, IR cut filter and Continuum filter"
VestaPro with 1/3" black and white sensor ...
... 800 frames stacked with IRIS ...
... Colors were added afterwards for aesthetical purpose
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FAQ
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Unmounted Filters – which side should face the telescope?
For our CMOS-optimized filters we have created the following images showing which side of the filter should face the telescope.
LEGACY FAQ for older unmounted CCD-Filters without black outer rim
Question in Detail:
I just bought LRGB 36mm unmounted filters. I have question: which side of filter should be placed towards telescope? Is it better way of distinguish than "more shiny surface towards telescope"?
Answer:
Always put the more reflective side towards the telescope side. To guide you we already put a small arrow on the filter rim, on those filters were the position matters. This arrow indicates which face of the filter should be directed towards the sky (telescope-sided). All cell-mounted filters are already oriented in a way that the most appropriate filter face is facing the sky when the filter would be mounted directly onto the front end of the nosepiece of a camera.
If you mount your filter the other way, any reflected light would have a short way to the camera sensor, resulting in a higher risk of getting some kind of back-reflections inside the camera field. Many sensors have highly reflective areas near to the light sensitive area, also the area with the bonding contacts is sometimes highly reflective.But: this is true only for instruments without optical elements near to the focal plane. If you have f.e. a coma corrector, field flattener, focal reducer, focal extender (to a lower degree due to concave surface), or in extreme cases a whole lens group for more complex field corrections a few centimeters in front of the filter it could be useful to flip the filter against the rule from above (thus having the arrow pointing away from the telescope). Cause in such cases the likelihood of reflections from the sensor could be lesser then fort- and back- reflections from such glass-surfaces. If in doubt, it helps to make some test images from a star field with bright stars, using the filter in both ways for comparison.
Should you really have some reflections with both positions it can be more effective to add a spacer between filter and camera, eventually shifting the reflection out of the image field. With focal correctors having curved surfaces changing the filter-lens distance could help also.
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HALOS – viewed without prejudice
For our CMOS-optimized filters we have created the following images showing which side of the filter should face the telescope.
LEGACY FAQ for older unmounted CCD-Filters without black outer rim
Question in Detail:
I just bought LRGB 36mm unmounted filters. I have question: which side of filter should be placed towards telescope? Is it better way of distinguish than "more shiny surface towards telescope"?
Answer:
Always put the more reflective side towards the telescope side. To guide you we already put a small arrow on the filter rim, on those filters were the position matters. This arrow indicates which face of the filter should be directed towards the sky (telescope-sided). All cell-mounted filters are already oriented in a way that the most appropriate filter face is facing the sky when the filter would be mounted directly onto the front end of the nosepiece of a camera.
If you mount your filter the other way, any reflected light would have a short way to the camera sensor, resulting in a higher risk of getting some kind of back-reflections inside the camera field. Many sensors have highly reflective areas near to the light sensitive area, also the area with the bonding contacts is sometimes highly reflective.But: this is true only for instruments without optical elements near to the focal plane. If you have f.e. a coma corrector, field flattener, focal reducer, focal extender (to a lower degree due to concave surface), or in extreme cases a whole lens group for more complex field corrections a few centimeters in front of the filter it could be useful to flip the filter against the rule from above (thus having the arrow pointing away from the telescope). Cause in such cases the likelihood of reflections from the sensor could be lesser then fort- and back- reflections from such glass-surfaces. If in doubt, it helps to make some test images from a star field with bright stars, using the filter in both ways for comparison.
Should you really have some reflections with both positions it can be more effective to add a spacer between filter and camera, eventually shifting the reflection out of the image field. With focal correctors having curved surfaces changing the filter-lens distance could help also.
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Off-standard single filter sizes from Baader - why not:
Quite often we receive requests for a single filter in an off-standard size. In all cases we are sorry that we must answer as follows:
Sorry (we know it would be so very much cheaper in production - and we would be so much more flexible to fill special requests) - but we have decided long ago to not cut or saw our filters from large plates because this would leave the coating stack open and mutilated (with microscopic cracks) all around, prone to aging and peeling.
Many times we had the chance to inspect our competitors filters after several years of use (due to our 30+years of servicing SBIG-CCD-cameras/and filter wheels) and we realized already 15 years ago how moisture and heat stress can deteriorate even most modern hard coatings, slowly peeling off from the carrying substrate over time, unless the coating stack is sealed all around the filter stack.
As a consequence - in order to create our filters to remain impermeable - we only offer all filter substrates already cut to final shape and run each substrate on an double deck auto-polisher to achieve perfect optical flatness and freedom from cone errors.
Then we do individually coat these substrates in 500 pc per run as minimum to fill a complete coating chamber, in a way that the coating stack (many times 50+ layers) applied onto each filter won't reach to the very edge of the round or square substrate, so that the coating stack remains completely sealed from all sides. In this way we can ensure that our filters will not age at all.The sad effect is that we cannot offer other sizes unless the inquired production quantity were in the range of 250 to 500 pc (depending on size) and the tooling rings or square holders will be paid for, which serve to precisely center each individual filter substrate within the rotating calotte inside the coating chamber. Sorry - as explained above - we just will not coat onto large plates and cut any shape from them, also because such large plates cannot be polished optically flat in the same way we do it.
For your most urgent need and for single piece solutions we can only recommend to order the next larger size of our respective filter and have that cut to shape by an ophtalmologist locally. We can supply the round filters without the metal cell in such cases; square filters come without cell in any case.
