GSO 12" f/4 Parabolic Primary and 88mm Secondary Telescope Mirror Set
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This set contains the following products:
For years, GSO has made dobsonian telescopes sold under various labels. Users of these scopes know the excellent quality of the optics included, and they have a well-deserved reputation for being the finest mirrors in their price range. We are now pleased to offer virtually the entire line of GSO's Newtonian optics in the US market.
GSO's parabolic primary mirrors are perfect for those who want to build their own telescopes or replace mirrors in older ones. Ranging in aperture from 6” to 16” and offered in various f-ratios, these mirrors are made from optical grade BK-7 glass. All mirrors have a reflective aluminum coating with a reflectivity of 92-93%. The aluminum coating is protected by a silicon oxide (SiO2) over-coating. GSO's elliptical flat mirrors have the same high quality as their parabolic primary mirrors.
GSO uses high-volume, state-of-the-art, high quality manufacturing and test lines. GSO guarantees diffraction limited performance, but their mirrors typically have a mirror surface quality of 1/16 wave RMS at least, and often better. This very smooth mirror surface results in excellent optical performance with practically no light scatter.
Please Note:
Most parabolic mirrors will have 2-4 minor uncoated areas along the edge of the mirror. See photo 3 above for an example. These are caused by the clips used to hold the mirrors in the coating chamber. Note that these are not defects. A couple of these uncoated edge strips will typically be covered up by the clips in your mirror cell anyway.
Additional Information:
Q. Is a test report included with each mirror?
A. No. GSO tests each mirror via laser interferometry before shipping, but does not provide individual test reports.
Q. Is the primary center-dotted?
A. No – the GSO primary mirrors we offer are not center-dotted.
You can easily center-dot the primary yourself following instructions readily available on the internet. If you want a free center-dotting sticker, just request one from us at the time you place your order. However, we do not offer center-dotting services.
| Specifications of GSO Primary Mirrors | |||||||
|---|---|---|---|---|---|---|---|
| Part Number | Aperture | Focal Ratio | Mirror Diameter | Focal Length | Mirror Thickness | Mirror Weight | Suggested Secondary Size |
| AD096 | 6" | f/4 | 153mm | 600mm | 20mm | 1lb-14oz (847g) | 62.5mm |
| AD046 | 6" | f/5 | 153mm | 750mm | 20mm | 2lb-1oz (941g) | 50mm |
| AD045 | 6" | f/6 | 153mm | 900mm | 20mm | 2lb (921g) | 50mm |
| AD011 | 6" | f/8 | 153mm | 1200mm | 20mm | 2lb (921g) | 31mm |
| AD048 | 8" | f/4 | 200mm | 800mm | 24mm | 3lb-15oz (1794g) | 70mm |
| AD049 | 8" | f/5 | 200mm | 1000mm | 24mm | 4lb-1oz (1831g) | 62.5mm |
| AD082 | 8" | f/6 | 200mm | 1200mm | 24mm | 3lb-13oz (1717g) | 50mm |
| AD094 | 10" | f/4 | 250mm | 1000mm | 34mm | 9lb-2oz (4126g) | 88mm |
| AD081 | 10" | f/5 | 250mm | 1250mm | 34mm | 8lb-9oz (3891g) | 62.5mm |
| AD095 | 12" | f/4 | 304mm | 1200mm | 38mm | 14lb-8oz (6574g) | 88mm |
| AD017 | 12" | f/5 | 304mm | 1500mm | 38mm | 14lb (6348g) | 70mm |
| AD015 | 16" | f/4.5 | 406mm | 1800mm | 45mm | 28lb-14oz (13092g) | 88mm |
| Specifications of GSO Secondary Mirrors | ||||
|---|---|---|---|---|
| Part Number | Minor Axis Diameter | Approx. Major Axis Diameter | Approx. Thickness | Mirror Weight |
| AD041 | 28mm | 38mm | 5mm | 0.3oz (9g) |
| AD012 | 31mm | 43mm | 8mm | 0.7oz (20g) |
| AD064 | 46.5mm | 65mm | 10mm | 2.1oz (60g) |
| AD007 | 50mm | 70mm | 10mm | 2.3oz (65g) |
| AD047 | 62.5mm | 88mm | 12mm | 4.5oz (128g) |
| AD091 | 68mm | 95mm | 15mm | 6.7oz (190g) |
| AD009 | 70mm | 97mm | 12mm | 5.5oz (156g) |
| AD092 | 74mm | 104mm | 16mm | 8.2oz (232g) |
| AD093 | 80mm | 114mm | 18mm | 11.5oz (326g) |
| AD037 | 88mm | 122mm | 20mm | 14.5oz (411g) |
| AD018 | 104mm | 145mm | 17mm | 18.2oz (515g) |
Other Information
- Country of Manufacture: Taiwan
For years, GSO has made dobsonian telescopes sold under various labels. Users of these scopes know the excellent quality of the optics included, and they have a well-deserved reputation for being the finest mirrors in their price range. We are now pleased to offer virtually the entire line of GSO's Newtonian optics in the US market.
GSO's parabolic primary mirrors are perfect for those who want to build their own telescopes or replace mirrors in older ones. Ranging in aperture from 6” to 16” and offered in various f-ratios, these mirrors are made from optical grade BK-7 glass. All mirrors have a reflective aluminum coating with a reflectivity of 92-93%. The aluminum coating is protected by a silicon oxide (SiO2) over-coating. GSO's elliptical flat mirrors have the same high quality as their parabolic primary mirrors.
GSO uses high-volume, state-of-the-art, high quality manufacturing and test lines. GSO guarantees diffraction limited performance, but their mirrors typically have a mirror surface quality of 1/16 wave RMS at least, and often better. This very smooth mirror surface results in excellent optical performance with practically no light scatter.
Please Note:
Most parabolic mirrors will have 2-4 minor uncoated areas along the edge of the mirror. See photo 3 above for an example. These are caused by the clips used to hold the mirrors in the coating chamber. Note that these are not defects. A couple of these uncoated edge strips will typically be covered up by the clips in your mirror cell anyway.
Additional Information:
Q. Is a test report included with each mirror?
A. No. GSO tests each mirror via laser interferometry before shipping, but does not provide individual test reports.
Q. Is the primary center-dotted?
A. No – the GSO primary mirrors we offer are not center-dotted.
You can easily center-dot the primary yourself following instructions readily available on the internet. If you want a free center-dotting sticker, just request one from us at the time you place your order. However, we do not offer center-dotting services.
| Specifications of GSO Primary Mirrors | |||||||
|---|---|---|---|---|---|---|---|
| Part Number | Aperture | Focal Ratio | Mirror Diameter | Focal Length | Mirror Thickness | Mirror Weight | Suggested Secondary Size |
| AD096 | 6" | f/4 | 153mm | 600mm | 20mm | 1lb-14oz (847g) | 62.5mm |
| AD046 | 6" | f/5 | 153mm | 750mm | 20mm | 2lb-1oz (941g) | 50mm |
| AD045 | 6" | f/6 | 153mm | 900mm | 20mm | 2lb (921g) | 50mm |
| AD011 | 6" | f/8 | 153mm | 1200mm | 20mm | 2lb (921g) | 31mm |
| AD048 | 8" | f/4 | 200mm | 800mm | 24mm | 3lb-15oz (1794g) | 70mm |
| AD049 | 8" | f/5 | 200mm | 1000mm | 24mm | 4lb-1oz (1831g) | 62.5mm |
| AD082 | 8" | f/6 | 200mm | 1200mm | 24mm | 3lb-13oz (1717g) | 50mm |
| AD094 | 10" | f/4 | 250mm | 1000mm | 34mm | 9lb-2oz (4126g) | 88mm |
| AD081 | 10" | f/5 | 250mm | 1250mm | 34mm | 8lb-9oz (3891g) | 62.5mm |
| AD095 | 12" | f/4 | 304mm | 1200mm | 38mm | 14lb-8oz (6574g) | 88mm |
| AD017 | 12" | f/5 | 304mm | 1500mm | 38mm | 14lb (6348g) | 70mm |
| AD015 | 16" | f/4.5 | 406mm | 1800mm | 45mm | 28lb-14oz (13092g) | 88mm |
| Specifications of GSO Secondary Mirrors | ||||
|---|---|---|---|---|
| Part Number | Minor Axis Diameter | Approx. Major Axis Diameter | Approx. Thickness | Mirror Weight |
| AD041 | 28mm | 38mm | 5mm | 0.3oz (9g) |
| AD012 | 31mm | 43mm | 8mm | 0.7oz (20g) |
| AD064 | 46.5mm | 65mm | 10mm | 2.1oz (60g) |
| AD007 | 50mm | 70mm | 10mm | 2.3oz (65g) |
| AD047 | 62.5mm | 88mm | 12mm | 4.5oz (128g) |
| AD091 | 68mm | 95mm | 15mm | 6.7oz (190g) |
| AD009 | 70mm | 97mm | 12mm | 5.5oz (156g) |
| AD092 | 74mm | 104mm | 16mm | 8.2oz (232g) |
| AD093 | 80mm | 114mm | 18mm | 11.5oz (326g) |
| AD037 | 88mm | 122mm | 20mm | 14.5oz (411g) |
| AD018 | 104mm | 145mm | 17mm | 18.2oz (515g) |
This set contains the following products:
For years, GSO has made dobsonian telescopes sold under various labels. Users of these scopes know the excellent quality of the optics included, and they have a well-deserved reputation for being the finest mirrors in their price range. We are now pleased to offer virtually the entire line of GSO's Newtonian optics in the US market.
GSO's parabolic primary mirrors are perfect for those who want to build their own telescopes or replace mirrors in older ones. Ranging in aperture from 6” to 16” and offered in various f-ratios, these mirrors are made from optical grade BK-7 glass. All mirrors have a reflective aluminum coating with a reflectivity of 92-93%. The aluminum coating is protected by a silicon oxide (SiO2) over-coating. GSO's elliptical flat mirrors have the same high quality as their parabolic primary mirrors.
GSO uses high-volume, state-of-the-art, high quality manufacturing and test lines. GSO guarantees diffraction limited performance, but their mirrors typically have a mirror surface quality of 1/16 wave RMS at least, and often better. This very smooth mirror surface results in excellent optical performance with practically no light scatter.
Please Note:
Most parabolic mirrors will have 2-4 minor uncoated areas along the edge of the mirror. See photo 3 above for an example. These are caused by the clips used to hold the mirrors in the coating chamber. Note that these are not defects. A couple of these uncoated edge strips will typically be covered up by the clips in your mirror cell anyway.
Additional Information:
Q. Is a test report included with each mirror?
A. No. GSO tests each mirror via laser interferometry before shipping, but does not provide individual test reports.
Q. Is the primary center-dotted?
A. No – the GSO primary mirrors we offer are not center-dotted.
You can easily center-dot the primary yourself following instructions readily available on the internet. If you want a free center-dotting sticker, just request one from us at the time you place your order. However, we do not offer center-dotting services.
| Specifications of GSO Primary Mirrors | |||||||
|---|---|---|---|---|---|---|---|
| Part Number | Aperture | Focal Ratio | Mirror Diameter | Focal Length | Mirror Thickness | Mirror Weight | Suggested Secondary Size |
| AD096 | 6" | f/4 | 153mm | 600mm | 20mm | 1lb-14oz (847g) | 62.5mm |
| AD046 | 6" | f/5 | 153mm | 750mm | 20mm | 2lb-1oz (941g) | 50mm |
| AD045 | 6" | f/6 | 153mm | 900mm | 20mm | 2lb (921g) | 50mm |
| AD011 | 6" | f/8 | 153mm | 1200mm | 20mm | 2lb (921g) | 31mm |
| AD048 | 8" | f/4 | 200mm | 800mm | 24mm | 3lb-15oz (1794g) | 70mm |
| AD049 | 8" | f/5 | 200mm | 1000mm | 24mm | 4lb-1oz (1831g) | 62.5mm |
| AD082 | 8" | f/6 | 200mm | 1200mm | 24mm | 3lb-13oz (1717g) | 50mm |
| AD094 | 10" | f/4 | 250mm | 1000mm | 34mm | 9lb-2oz (4126g) | 88mm |
| AD081 | 10" | f/5 | 250mm | 1250mm | 34mm | 8lb-9oz (3891g) | 62.5mm |
| AD095 | 12" | f/4 | 304mm | 1200mm | 38mm | 14lb-8oz (6574g) | 88mm |
| AD017 | 12" | f/5 | 304mm | 1500mm | 38mm | 14lb (6348g) | 70mm |
| AD015 | 16" | f/4.5 | 406mm | 1800mm | 45mm | 28lb-14oz (13092g) | 88mm |
| Specifications of GSO Secondary Mirrors | ||||
|---|---|---|---|---|
| Part Number | Minor Axis Diameter | Approx. Major Axis Diameter | Approx. Thickness | Mirror Weight |
| AD041 | 28mm | 38mm | 5mm | 0.3oz (9g) |
| AD012 | 31mm | 43mm | 8mm | 0.7oz (20g) |
| AD064 | 46.5mm | 65mm | 10mm | 2.1oz (60g) |
| AD007 | 50mm | 70mm | 10mm | 2.3oz (65g) |
| AD047 | 62.5mm | 88mm | 12mm | 4.5oz (128g) |
| AD091 | 68mm | 95mm | 15mm | 6.7oz (190g) |
| AD009 | 70mm | 97mm | 12mm | 5.5oz (156g) |
| AD092 | 74mm | 104mm | 16mm | 8.2oz (232g) |
| AD093 | 80mm | 114mm | 18mm | 11.5oz (326g) |
| AD037 | 88mm | 122mm | 20mm | 14.5oz (411g) |
| AD018 | 104mm | 145mm | 17mm | 18.2oz (515g) |
Other Information
- Country of Manufacture: Taiwan
GSO 12" f/4 Parabolic Primary and 88mm Secondary Telescope Mirror Set