IDAS DS (AD42-DS)
M42 Slot Drop-in Filter Mount System & Dedicated DS Filters
Built-in 360° Rotator & M42 Drop-in Filter System
The IDAS DS System (Mount body: AD42-DS) is a high-precision drop-in filter holder designed to swap filters instantly without detaching cameras or telescopes.
Equipped with M42 P=0.75 female threads on both telescope and camera sides (via rear tapered rotation ring).
Features an integrated 360-degree camera field rotator with 3 knurled locking thumbscrews, engineered with uncompromising rigidity to prevent sensor tilt, vignetting, and stray reflections.
No need to unthread and disassemble heavy imaging trains in the dark.
Simply slide DS filters into the top slot for fast, secure filter changes.
The AD42-DS comes standard with an optical-grade Clear DS filter to maintain exact focal position and seal the camera against dust when no specialized filter is in use.
The rear camera interface features a precision-machined taper ring clamped by three knurled brass thumbscrews.
Loosen slightly to rotate your camera freely 360 degrees for ideal framing, and tighten down securely without introducing sensor tilt or rotational drift.
The custom DS filter holder provides a generous φ34mm clear aperture, ensuring virtually zero vignetting on APS-C and Four Thirds sensors.
Manufactured on 1.1mm flat-polished optical glass with IDAS multi-layer interference coatings for exceptional contrast and ghost-free stars.
Keeping the included Clear DS filter inserted during unfiltered sessions ensures parfocal performance when switching between specialized DS filters (DTD, GNB, etc.), minimizing refocusing in the field.
Pairs cleanly with cooled astro cameras and extension tubes to hit standard 55mm backfocus requirements.
• Askar N160: Requires optional extension tube
Specifications & Compatibility
| Model Number | AD42-DS (IDAS M42 Drop-in Filter Holder) |
|---|---|
| Telescope Thread | M42 P=0.75 Female |
| Camera Thread | M42 P=0.75 Female (Inside Tapered Rotation Ring) |
| Physical Path Length | 19.84mm |
| Optical Path Length | 19.5mm (with DS filter installed) |
| 360° Manual Field Rotator (3-Point Knurled Thumbscrews) | 360° Manual Camera Rotator (3-point knurled locking screws) |
| Clear Aperture | φ34mm (APS-C / Four Thirds Compatible) |
| Filter Glass Thickness | 1.1mm |
| Recommended OTA | Celestron 8 RASA (Ready to use / Direct fit) Askar N160 (Requires optional extension tube) |
| Included Accessories | [AD42-DS Holder Unit Set] AD42-DS Body, Clear DS Filter × 1 included [Individual DS Filters (DTD / GNB / NGS1 / HEUIB-II / NB1)] Dedicated Filter × 1 (* Holder unit sold separately) |
| Country of Origin | Made in Japan (ICAS Enterprises Optics Division) |
Limited Edition AD42-DS Lineup
Special bundle of the AD42-DS 360-degree rotator body and dedicated DS filters.
Available through authorized dealer network and BASE.
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AD42-DS ＋ GNB DS
[Package Content] AD42-DS Body (with Clear DS) + GNB DS
[Primary Application] Galaxy & Nebula Booster opening NIR alongside OIII/Hα.
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AD42-DS ＋ DTD DS
[Package Content] AD42-DS Body (with Clear DS) + DTD DS
[Primary Application] Next-gen broadband & NIR dusk-to-dawn nebula booster.
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AD42-DS ＋ HEUIB-II DS
[Package Content] AD42-DS Body (with Clear DS) + HEUIB-II DS
[Primary Application] Hα-enhanced UV/IR cut filter. Ideal for modified DSLRs.
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AD42-DS ＋ NGS1 DS
[Package Content] AD42-DS Body (with Clear DS) + NGS1 DS
[Primary Application] Natural nightglow and light pollution cut filter. LPS-D3 successor.
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AD42-DS ＋ NB1 DS
[Package Content] AD42-DS Body (with Clear DS) + NB1 DS
[Primary Application] Triple-band nebula booster (Hβ, OIII, Hα, NII).