OPTEC Perseus 4-Port Instrument Selector (Gen 3)
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- Instantly switch between four ports that can mount cameras, imaging accessories, or eyepieces without reconfiguring your setup.
- Precision 3-inch rotating mirror delivers accurate, repeatable alignment.
- USB, Serial, and Ethernet control ready for robotic observatories.
- Supports multiple cameras, eyepieces, and instruments on one telescope.
OPTEC Perseus 4-Port Instrument Selector
Expand the versatility of your observatory-class telescope with the third-generation Optec Perseus 4-Port Instrument Selector, the premium solution for seamlessly switching between multiple cameras, scientific instruments, or eyepieces without rebuilding your imaging train. Engineered for demanding observatory use, the Perseus GEN3 features a rugged, precision-built housing, a reliable U.S.-made Lin Engineering stepper motor, and a redesigned control system for smooth, dependable performance. A hard mechanical stop ensures repeatable positional accuracy every time you change ports, making it ideal for imaging, research, and automated remote operation.
A large precision 3-inch diagonal mirror directs incoming light to one primary 3-inch port or any of three 2-inch accessory ports, giving you outstanding flexibility for multi-instrument setups. Built for modern robotic observatories, the Perseus GEN3 includes USB, Serial, and Ethernet connectivity, with support for ASCOM software plus smartphone and tablet control on iPhone, iPad, and Android devices. At the telescope, a simple push-button interface and LED status indicators make manual operation quick and convenient for outreach events or visual observing.
Perseus 4-port Instrument Selector
Back-Focus Planning and Calculator
Perseus Port 1
OPL Total – Port 1 173.4 mm / 6.83 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 1 | OPTEC-3600 dovetail seat | 114.5 | 4.51 | ||
| 3-inch Receiver | #17880 | OPTEC-3000 receiver | 10.2 | 0.40 | |
| STL camera mount | #17806 | 4-bolt plate for STL camera | 2.5 | 0.10 | |
| SBIG STL with FW8 | CCD sensor surface | 46.2 | 1.82 | per SBIG website. |
Port 2
OPL Total – Port 2 201.7 mm / 7.94 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 2 | OPTEC-2400 dovetail seat | 110.2 | 4.34 | ||
| TCF-S focuser | #17670 | top of 2-inch drawtube (midpoint) | 91.5 | 3.60 | |
| 2-inch eyepiece | 0.0 | 0.00 | varies by eyepiece |
Port 3
OPL Total – Port 3 174.0 mm / 6.85 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 3 | Top of red OPTEC-2300 receiver | 127.0 | 5.00 | Parfocal receiver fully retracted | |
| OPTEC-2300 to T thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T- to C-mount adapter | #19853 | base of C-adapter | 30.0 | 1.18 | |
| C- to CS adapter | #19791 | base of C-adapter | 2.0 | 0.08 | Required for this camera. |
| Skyris planetary camera | CMOS sensor surface | 12.5 | 0.49 | Standard CS-mount distance |
Port 4
OPL Total – Port 4 174.7 mm / 6.88 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 4 | Top of red OPTEC-2300 receiver | 139.7 | 5.50 | Parfocal receiver fully extended | |
| OPTEC-2300 to T-thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T-thread extender | #19633 | base of T-thread | 15.0 | 0.59 | |
| ZWO ASI camera | 17.5 | 0.69 | per ZWO spec page |
1 - Last Interface from telescope objective for this adapter. This surface is closest to the telescope focus.
*OPL - Optical Path Length through this adapter/component.
Specifications:
-
Overall Height: 7.00" (178 mm)
-
Main Body Diameter: 4.25" (108 mm)
-
Weight: 5 lb. (2.25 kg)
-
Telescope Adapter: OPTEC-3600 Female Dovetail Mount
-
Instrument Ports: Three 2-inch & One 3-inch
-
Primary Port #1:
-
Mechanical Interface: OPTEC-3600 Male Dovetail
-
Clear Aperture: 3.0" (76mm)
-
Back-focus usage: 4.5" (115mm)
-
Recommended adapter: #17880 OPTEC-3000 3-inch receiver
-
-
Secondary Ports #2, #3, #4:
-
Primary Mechanical Interface: OPTEC-2400 Male Dovetail
-
Clear Aperture: 2.1" (53mm)
-
Back-focus usage: 4.3 in (110 mm)
-
Secondary Interface: Parfocal adjusting ring with OPTEC-2300 Receiver
-
Clear Aperture: 1.9" (48mm)
-
Back-focus usage: 5.0" to 5.5" (127mm to 140mm)
-
-
Total Parfocal Travel: 0.5 in (12.7 mm)
-
Thread Options: M54x0.75mm, T-thread, SCT thread, C-mount.
-
Control Interface: Push-button Selection
-
Communications Interface: Ethernet, USB/Serial
-
Software Interface: Perseus Commander with ASCOM and Alpaca drivers.
Other Information
- Country of Manufacture: United States
OPTEC Perseus 4-Port Instrument Selector
Expand the versatility of your observatory-class telescope with the third-generation Optec Perseus 4-Port Instrument Selector, the premium solution for seamlessly switching between multiple cameras, scientific instruments, or eyepieces without rebuilding your imaging train. Engineered for demanding observatory use, the Perseus GEN3 features a rugged, precision-built housing, a reliable U.S.-made Lin Engineering stepper motor, and a redesigned control system for smooth, dependable performance. A hard mechanical stop ensures repeatable positional accuracy every time you change ports, making it ideal for imaging, research, and automated remote operation.
A large precision 3-inch diagonal mirror directs incoming light to one primary 3-inch port or any of three 2-inch accessory ports, giving you outstanding flexibility for multi-instrument setups. Built for modern robotic observatories, the Perseus GEN3 includes USB, Serial, and Ethernet connectivity, with support for ASCOM software plus smartphone and tablet control on iPhone, iPad, and Android devices. At the telescope, a simple push-button interface and LED status indicators make manual operation quick and convenient for outreach events or visual observing.
Perseus 4-port Instrument Selector
Back-Focus Planning and Calculator
Perseus Port 1
OPL Total – Port 1 173.4 mm / 6.83 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 1 | OPTEC-3600 dovetail seat | 114.5 | 4.51 | ||
| 3-inch Receiver | #17880 | OPTEC-3000 receiver | 10.2 | 0.40 | |
| STL camera mount | #17806 | 4-bolt plate for STL camera | 2.5 | 0.10 | |
| SBIG STL with FW8 | CCD sensor surface | 46.2 | 1.82 | per SBIG website. |
Port 2
OPL Total – Port 2 201.7 mm / 7.94 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 2 | OPTEC-2400 dovetail seat | 110.2 | 4.34 | ||
| TCF-S focuser | #17670 | top of 2-inch drawtube (midpoint) | 91.5 | 3.60 | |
| 2-inch eyepiece | 0.0 | 0.00 | varies by eyepiece |
Port 3
OPL Total – Port 3 174.0 mm / 6.85 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 3 | Top of red OPTEC-2300 receiver | 127.0 | 5.00 | Parfocal receiver fully retracted | |
| OPTEC-2300 to T thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T- to C-mount adapter | #19853 | base of C-adapter | 30.0 | 1.18 | |
| C- to CS adapter | #19791 | base of C-adapter | 2.0 | 0.08 | Required for this camera. |
| Skyris planetary camera | CMOS sensor surface | 12.5 | 0.49 | Standard CS-mount distance |
Port 4
OPL Total – Port 4 174.7 mm / 6.88 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 4 | Top of red OPTEC-2300 receiver | 139.7 | 5.50 | Parfocal receiver fully extended | |
| OPTEC-2300 to T-thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T-thread extender | #19633 | base of T-thread | 15.0 | 0.59 | |
| ZWO ASI camera | 17.5 | 0.69 | per ZWO spec page |
1 - Last Interface from telescope objective for this adapter. This surface is closest to the telescope focus.
*OPL - Optical Path Length through this adapter/component.
Specifications:
-
Overall Height: 7.00" (178 mm)
-
Main Body Diameter: 4.25" (108 mm)
-
Weight: 5 lb. (2.25 kg)
-
Telescope Adapter: OPTEC-3600 Female Dovetail Mount
-
Instrument Ports: Three 2-inch & One 3-inch
-
Primary Port #1:
-
Mechanical Interface: OPTEC-3600 Male Dovetail
-
Clear Aperture: 3.0" (76mm)
-
Back-focus usage: 4.5" (115mm)
-
Recommended adapter: #17880 OPTEC-3000 3-inch receiver
-
-
Secondary Ports #2, #3, #4:
-
Primary Mechanical Interface: OPTEC-2400 Male Dovetail
-
Clear Aperture: 2.1" (53mm)
-
Back-focus usage: 4.3 in (110 mm)
-
Secondary Interface: Parfocal adjusting ring with OPTEC-2300 Receiver
-
Clear Aperture: 1.9" (48mm)
-
Back-focus usage: 5.0" to 5.5" (127mm to 140mm)
-
-
Total Parfocal Travel: 0.5 in (12.7 mm)
-
Thread Options: M54x0.75mm, T-thread, SCT thread, C-mount.
-
Control Interface: Push-button Selection
-
Communications Interface: Ethernet, USB/Serial
-
Software Interface: Perseus Commander with ASCOM and Alpaca drivers.
- 1x Perseus Instrument Selector
- 1x 3-inch Port 1 with cover
- 3x 2-inch Ports 2-4 with parfocal rings and covers
- 1x Optec USB/Serial communications cable, 6-ft. length
- 1x CAT-5e/CAT-6 Ethernet cable, 6-ft. length
- 1x 12VDC 1.25A power supply - 110-240VAC input
- 1x UL/CSA compliant wall plug cord,
- 1x Tool kits including 0.050", 3/32", and 7/64" ball-drivers
- 1x Covers for OPTEC-3600 mounting interface
- 1x Pelican shipping and storage case
- Instantly switch between four ports that can mount cameras, imaging accessories, or eyepieces without reconfiguring your setup.
- Precision 3-inch rotating mirror delivers accurate, repeatable alignment.
- USB, Serial, and Ethernet control ready for robotic observatories.
- Supports multiple cameras, eyepieces, and instruments on one telescope.
OPTEC Perseus 4-Port Instrument Selector
Expand the versatility of your observatory-class telescope with the third-generation Optec Perseus 4-Port Instrument Selector, the premium solution for seamlessly switching between multiple cameras, scientific instruments, or eyepieces without rebuilding your imaging train. Engineered for demanding observatory use, the Perseus GEN3 features a rugged, precision-built housing, a reliable U.S.-made Lin Engineering stepper motor, and a redesigned control system for smooth, dependable performance. A hard mechanical stop ensures repeatable positional accuracy every time you change ports, making it ideal for imaging, research, and automated remote operation.
A large precision 3-inch diagonal mirror directs incoming light to one primary 3-inch port or any of three 2-inch accessory ports, giving you outstanding flexibility for multi-instrument setups. Built for modern robotic observatories, the Perseus GEN3 includes USB, Serial, and Ethernet connectivity, with support for ASCOM software plus smartphone and tablet control on iPhone, iPad, and Android devices. At the telescope, a simple push-button interface and LED status indicators make manual operation quick and convenient for outreach events or visual observing.
Perseus 4-port Instrument Selector
Back-Focus Planning and Calculator
Perseus Port 1
OPL Total – Port 1 173.4 mm / 6.83 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 1 | OPTEC-3600 dovetail seat | 114.5 | 4.51 | ||
| 3-inch Receiver | #17880 | OPTEC-3000 receiver | 10.2 | 0.40 | |
| STL camera mount | #17806 | 4-bolt plate for STL camera | 2.5 | 0.10 | |
| SBIG STL with FW8 | CCD sensor surface | 46.2 | 1.82 | per SBIG website. |
Port 2
OPL Total – Port 2 201.7 mm / 7.94 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 2 | OPTEC-2400 dovetail seat | 110.2 | 4.34 | ||
| TCF-S focuser | #17670 | top of 2-inch drawtube (midpoint) | 91.5 | 3.60 | |
| 2-inch eyepiece | 0.0 | 0.00 | varies by eyepiece |
Port 3
OPL Total – Port 3 174.0 mm / 6.85 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 3 | Top of red OPTEC-2300 receiver | 127.0 | 5.00 | Parfocal receiver fully retracted | |
| OPTEC-2300 to T thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T- to C-mount adapter | #19853 | base of C-adapter | 30.0 | 1.18 | |
| C- to CS adapter | #19791 | base of C-adapter | 2.0 | 0.08 | Required for this camera. |
| Skyris planetary camera | CMOS sensor surface | 12.5 | 0.49 | Standard CS-mount distance |
Port 4
OPL Total – Port 4 174.7 mm / 6.88 in
| Component Description | Optec Stk# | Last Interface¹ | OPL* mm | inches | Notes |
|---|---|---|---|---|---|
| Perseus body - Port 4 | Top of red OPTEC-2300 receiver | 139.7 | 5.50 | Parfocal receiver fully extended | |
| OPTEC-2300 to T-thread | #17646 | base of T-thread | 2.5 | 0.10 | |
| T-thread extender | #19633 | base of T-thread | 15.0 | 0.59 | |
| ZWO ASI camera | 17.5 | 0.69 | per ZWO spec page |
1 - Last Interface from telescope objective for this adapter. This surface is closest to the telescope focus.
*OPL - Optical Path Length through this adapter/component.
Specifications:
-
Overall Height: 7.00" (178 mm)
-
Main Body Diameter: 4.25" (108 mm)
-
Weight: 5 lb. (2.25 kg)
-
Telescope Adapter: OPTEC-3600 Female Dovetail Mount
-
Instrument Ports: Three 2-inch & One 3-inch
-
Primary Port #1:
-
Mechanical Interface: OPTEC-3600 Male Dovetail
-
Clear Aperture: 3.0" (76mm)
-
Back-focus usage: 4.5" (115mm)
-
Recommended adapter: #17880 OPTEC-3000 3-inch receiver
-
-
Secondary Ports #2, #3, #4:
-
Primary Mechanical Interface: OPTEC-2400 Male Dovetail
-
Clear Aperture: 2.1" (53mm)
-
Back-focus usage: 4.3 in (110 mm)
-
Secondary Interface: Parfocal adjusting ring with OPTEC-2300 Receiver
-
Clear Aperture: 1.9" (48mm)
-
Back-focus usage: 5.0" to 5.5" (127mm to 140mm)
-
-
Total Parfocal Travel: 0.5 in (12.7 mm)
-
Thread Options: M54x0.75mm, T-thread, SCT thread, C-mount.
-
Control Interface: Push-button Selection
-
Communications Interface: Ethernet, USB/Serial
-
Software Interface: Perseus Commander with ASCOM and Alpaca drivers.
Other Information
- Country of Manufacture: United States
- 1x Perseus Instrument Selector
- 1x 3-inch Port 1 with cover
- 3x 2-inch Ports 2-4 with parfocal rings and covers
- 1x Optec USB/Serial communications cable, 6-ft. length
- 1x CAT-5e/CAT-6 Ethernet cable, 6-ft. length
- 1x 12VDC 1.25A power supply - 110-240VAC input
- 1x UL/CSA compliant wall plug cord,
- 1x Tool kits including 0.050", 3/32", and 7/64" ball-drivers
- 1x Covers for OPTEC-3600 mounting interface
- 1x Pelican shipping and storage case
OPTEC Perseus 4-Port Instrument Selector (Gen 3)