Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228

Our Price: $22.00
Free shipping for this item in the US Click here for more info

Contiguous US Customers:
All items we sell ship for free within the Contiguous US. Shipping will be via the cheapest shipping method which will vary depending on the items in your order. During checkout, you may also be shown other optional faster shipping choices.

US Customers in Hawaii and Alaska:
Free shipping applies to almost all products. A few large telescopes and mounts are excluded from this free shipping offer. For these items, please contact us to obtain a shipping quote before you check out using the online shopping cart.

International Customers:
Free shipping does not apply to international orders. During check-out, you will be presented with several shipping choices and costs. However, the export of some items may be restricted outside the US due to size or manufacturer restrictions.

In Stock (10+ Available)
Ships by Next Business Day
Our Product ID: PAAR-BP-HDFT-28
Manufacturer SKU: 2958228
Item Can Ship: Worldwide
Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228

More Views

  • Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228
  • Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228
  • Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228
  • Baader Hyperion Finetuning Ring - 28mm # HDFT-28 2958228

Product Details

With the addition of Baader's new Finetuning Rings, each Hyperion eyepiece can now function as four eyepieces! Available in 14mm and 28mm lengths.  The finetuning rings are 2" OD and threaded M48 (filter thread) on each end, so they can be installed in-between the Hyperion's removable front negative element and main body. The added spacing decreases the focal lengths (increases magnification), according to the table below. Finetuning rings are made to match the Hyperion finish, and are fully internally sharp v-threaded and blackened to eliminate stray light reflections from the internal surfaces.

Also, another novel way to change eyepiece focal length is to use a Baader 2" filter in-between the Hyperion negative element and main body, just like a small finetuning ring. The 8.5mm thickness of the filter cell will have a similar (milder) effect in reducing the Hyperion's focal length. This also allows use of 2" filters with Hyperions, something that is not possible with any other 1.25" eyepiece.

Please Note: Removal and installation of the front negative element should be done in a clean environment to prevent dust or other contamination from depositing on the internal elements (which are very difficult to clean). Also, please note that the 24mm Hyperion is not able to make use of the Finetuning Rings, due to its different optical design.

Hyperion EP With 14mm Ring With 28mm Ring With 14 + 28mm Rings With Baader 2" Filter
21 mm 17.6 15.5 14.0 18.5
17 mm 13.1 10.8 9.2 14.6
13 mm 10.8 9.2 8.1 11.7
10 mm ~7.9 ~6.7 ~5.8 ~8.8
8 mm 6.0 5.0 4.3 6.9
5 mm 4.0 3.2 2.6 4.3
3.5 mm 2.5 2.1 1.8 2.9

The new 10mm Hyperion eyepiece will also benefit from the use of these rings. While there are no official numbers from Baader, we estimate that the 10mm will function approximately as a 7.9mm eyepiece with the 14mm ring, a 6.7mm eyepiece with the 28mm ring, and a 5.8mm eyepiece with the 14+28mm rings.