How do I use the SVBONY M42x0.75 Extension Tube Kit to get a specific distance?

You can combine the different tubes to achieve your desired length. For example, if you need 25mm of spacing, you would thread the 5mm and 20mm tubes together. The kit allows you to create any length in 5mm increments up to the 50mm maximum.

What is the maximum extension I can achieve with the SVBONY M42 kit?

The maximum extension is 50mm, achieved by connecting all four tubes (5mm + 10mm + 15mm + 20mm) together.

Will these SVBONY extension tubes work with my astronomy camera and accessories?

Yes, if your equipment uses the standard M42x0.75mm T2 thread. This is the most common thread size for astronomy cameras, filter wheels, off-axis guiders, and many field flatteners and reducers.

My flattener needs 18mm of back focus. Can I achieve this with the SVBONY M42 kit?

This kit can provide 15mm or 20mm of spacing, but not exactly 18mm. For such precise, non-5mm increments, you would typically use the 15mm tube from this kit and add a separate, smaller 3mm spacer or a fine-tuning variable ring to achieve the exact distance.

I'm connecting my telescope to a DSLR with an M42 T-ring. Can this SVBONY kit adjust the spacing?

Absolutely. The M42 T-ring for your DSLR has female M42x0.75mm threads. You can place any combination of these extension tubes between your telescope's flattener/reducer and the T-ring to set the correct distance to the DSLR's sensor.

Are the threads on the SVBONY M42 extension tubes the same as T2 threads?

Yes. The designation M42x0.75mm refers to a metric thread with a 42mm diameter and a 0.75mm thread pitch. This is the specification for the universal "T2" thread used in astrophotography.

SVBONY M42x0.75 Extension Tube Kit (5mm, 10mm, 15mm, 20mm)

SVBONY M42x0.75 Extension Tube Kit (5mm, 10mm, 15mm, 20mm)

by SVBONY

SKU SV-F9160A

CA$26.00 - CA$26.00

CA$26.00

CA$26.00 - CA$26.00

CA$26.00

Price Match Policy!

Includes four M42 extension tubes: 5mm, 10mm, 15mm, and 20mm
Standard M42x0.75mm T2 male and female threads
Stackable to achieve combined lengths from 5mm to 50mm
Durable all-metal, black anodized construction
Resolves back focus spacing for field flatteners and focal reducers

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SVBONY M42x0.75 Extension Tube Kit (5mm, 10mm, 15mm, 20mm)

The SVBONY M42x0.75 Extension Tube Kit solves critical back focus issues with four separate metal spacers—5mm, 10mm, 15mm, and 20mm—designed for flatteners and reducers. With standard M42x0.75mm male and female threads, these tubes can be combined in any order to achieve precise extension lengths from 5mm up to 50mm in 5mm increments.

Dial In Perfect Spacing: 5mm to 50mm of M42x0.75 Extension

Field flatteners and focal reducers require a precise distance to the camera sensor to deliver sharp stars across the frame. This SVBONY kit gives you the tools to hit that target distance precisely. The set includes four separate tubes of 5mm, 10mm, 15mm, and 20mm lengths.

By stacking the tubes, you can create any spacing you need in 5mm steps, all the way up to a total of 50mm when all four are used together. This flexibility eliminates guesswork and allows you to build out your imaging train to the exact specification your optics require.

All-Metal Construction for a Zero-Flex Imaging Train

Each extension tube in the kit is machined from metal with a black anodized finish to ensure rigidity and minimize internal reflections. The precise M42x0.75mm threads (the common T2 standard) guarantee a secure, flex-free connection between your camera and accessories.

Unlike variable or plastic spacers, these fixed-length metal tubes create a solid, stable optical train. This rigidity is critical for astrophotography, as it prevents sensor tilt and ensures that your optical alignment remains perfect throughout a long imaging session.
How do I use the SVBONY M42x0.75 Extension Tube Kit to get a specific distance?

You can combine the different tubes to achieve your desired length. For example, if you need 25mm of spacing, you would thread the 5mm and 20mm tubes together. The kit allows you to create any length in 5mm increments up to the 50mm maximum.

What is the maximum extension I can achieve with the SVBONY M42 kit?

The maximum extension is 50mm, achieved by connecting all four tubes (5mm + 10mm + 15mm + 20mm) together.

Will these SVBONY extension tubes work with my astronomy camera and accessories?

Yes, if your equipment uses the standard M42x0.75mm T2 thread. This is the most common thread size for astronomy cameras, filter wheels, off-axis guiders, and many field flatteners and reducers.

My flattener needs 18mm of back focus. Can I achieve this with the SVBONY M42 kit?

This kit can provide 15mm or 20mm of spacing, but not exactly 18mm. For such precise, non-5mm increments, you would typically use the 15mm tube from this kit and add a separate, smaller 3mm spacer or a fine-tuning variable ring to achieve the exact distance.

I'm connecting my telescope to a DSLR with an M42 T-ring. Can this SVBONY kit adjust the spacing?

Absolutely. The M42 T-ring for your DSLR has female M42x0.75mm threads. You can place any combination of these extension tubes between your telescope's flattener/reducer and the T-ring to set the correct distance to the DSLR's sensor.

Are the threads on the SVBONY M42 extension tubes the same as T2 threads?

Yes. The designation M42x0.75mm refers to a metric thread with a 42mm diameter and a 0.75mm thread pitch. This is the specification for the universal "T2" thread used in astrophotography.
Material Metal

Male Thread M42x0.75mm (T2)

Female Thread M42x0.75mm (T2)

Included Lengths 5mm, 10mm, 15mm, 20mm

Color Black
- 5mm M42x0.75 Extension Tube
  
  × 1
- 10mm M42x0.75 Extension Tube
  
  × 1
- 15mm M42x0.75 Extension Tube
  
  × 1
- 20mm M42x0.75 Extension Tube
  
  × 1
SVBONY 1-Year Warranty

SVBONY M42x0.75 Extension Tube Kit (5mm, 10mm, 15mm, 20mm)