Current Price: $545.00
Buy It Now Price: $545.00
Bids: 0

GSO Parabolic Primary Mirror - 12" f/5

Description Ordering Info USA Shipping International Orders Returns Our eBay Store


Please Note: This mirror in stock at this time is NOT center-dotted.

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 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.

Besides parabolic primaries, we also offer matching GSO secondary elliptical mirrors, mirror cells, and spiders (all sold separately).

Please Note:

Most parabolic mirrors will have 2-4 minor uncoated areas along the edge of the mirror. See photo 2 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. Sometimes yes but mostly no. It just varies from batch to batch.

You can easily center-dot the primary yourself if the mirror you receive is not dotted. Instructions to do this are readily available on the internet. If you want a center-dotting sticker, just request one from us at the time you place your order.

If you want a mirror that does not have this center dot, please check with us before your purchase. Removing the center dot is not easy or recommended. If the mirror already has a center dot but you do not want it, we recommend that you not purchase this item.


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 Notes:
Actual measurements can vary by a little bit from all values shown above due to manufacturing variations.
Actual coated mirror diameter will be 2-3 mm less than the Mirror Diameter listed above.


Note: Occasionally, the product you receive might have a slightly different cosmetic appearance or labeling than what is shown. This can often change from batch to batch according to the whims of the manufacturer. However, you will always receive a brand new, original product as described above.

Back to Top

Filed under: Eyepieces & Accessories