M48 external thread: 3MM. - M48 internal thread: 5MM. Usually it costs about 30USD-50USD.
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NOTE: This kit fits Olympus 4/3 Mount DSLRs, it DOES NOT FIT. Olympus "MICRO 4/3" Mount Mirrorless Models (See # NPM43). From the widest possible field to the highest magnification is covered using your standard 1.25" Plossl eyepieces.
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Features: The extension tube set is used to obtain the correct image focal length or exact spacing required, therebysolving the spacing problem in astrophotography. Length:approx 3mm 5mm 10mm 15mm 20mm 30mm.
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The M42x0.75 threadson both ends make it versatile. External thread M42x 0.75; internal thread M42x0.75;. Male thread: M42x0.75mm. Female thread: M42x0.75mm. Features: The extension tube set is used to obtain the correct image focal length or exact spacing required, therebysolving the spacing problem in astrophotography.
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The ring adapter can't auto focusing :The adapter ring has no electrical connection and diaphragm & focusing are required to be set by manual. 1 X Photography Extension Tube. Thread: Both the adapter are universal M42x0.75 thread.
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For Precise Focusing: Flip mirror makes easy to find exact focus point and also correct position for astrophotography; this small black box has a moveable flip mirror which shunts light path 90 degree upwards; alternatively lets it pass through unhindered.
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The 4um large pixel makes it suitable for guiding. QHY5III (Ver. - Model: QHY5III200M. The QHY5III (Ver. In this latest generation of sensors, the photodiode portion of the pixel well is physically deeper than in previous sensors, allowing photons of longer wavelengths to penetrate deeper into the substrate. ).
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