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Vixen Telescope SD Reducer HD Kit


Regular price
Price: $579.99 USD
Regular price
List Price: $599.99 USD
Sale price
Price: $579.99 USD
You save: $20.00 (3%)
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Availability: Pre-order

Estimated Arrival: Between Aug 12 and Aug 26. United States

Ships within 4-7 days

  • Description
  • Shipping & Returns
  • Price Match
  • Warranty
  • Reviews
  • Product Q&A
  • Manuals


The kit consists of the high-performance flattener lens, reducer lens and connecting rings (Spacer Ring SD81, EX Tube 66) designed for prime focus astrophotography with the SD81S, SD103S and SD115S optical tubes, extraordinary enhancing the flat-field performance, while reducing the focal length by 0.79x. Enjoy high-level prime focus astrophotography by SD series optical tubes which supply two different focal length.

The SD flattener HD improves the flat-field performance toward the edge of field of view closely maintaining the original focal length of the SD-series optical tubes, fully covering the imaging field of DSLR camera with full-format sensor at image circle of 44mm diameter. Using in combination with the supplied Reducer HD, the focal length will be reduced by 0.79x (f/7.7→6.1), while maintaining image circle in dia. 44mm, largely improving sharpness over the entire imaging field of the DSLR camera with full-format sensor.

The same anti-reflective AS coating, which are used for our high-end VSD 100 f/3.8 Astrograph, are used to take advantage of 99.9% superb high transmission of light per lens surface. Loss of light, ghost and flare images are eliminated substantially due to the complete matte finish inside.

The supplied Reducer HD can be used as a reducer for the AX103S and VC200L optical tubes. The AX103S optical tube incorporates a flattener lens and outperforms high imaging capability even by itself. From this reason, the Reducer HD can be used without using the SD Flattener HD. The AX103S covers an imaging field of DSLR camera with full-format sensor with 44mm image circle.

Originally incorporating a flattener lens inside, the VC200L optical tube offers high imaging capability by itself. For this reason, the Reducer HD can be used without using the SD Flattener HD together. The VC200L delivers 36mm image circle (peripheral illumination by 60%) fully covering an imaging field of DSLR camera with APS-C sensor, and also offers comparably sharp images with the center in spite of 47% peripheral illumination at dia. 44mm image circle. It covers an imaging field of DSLR camera with image circle of dia. 28.8mm with APS-C sensor and dia. 44mm with full-format sensor.

Full-format and APS-C is a common name for size representing the size of the light-receiving plane (imaging sensor or film) of DSLR camera. Full-format (36x24mm), APS-C (23x16mm) and Four Thirds (17.3x13mm) are typical available standard for DSLR cameras. In general, the larger the light-receiving plane, the larger the range can be shot.

Specification :

SD Flattener HD 2 elements in 1 group; Reducer HD : 2 elements in 2 group
Coating AS Coating (Over 99.9% light transmission on every single surface)
Size/Weight SD Flattener HD : Φ58×34mm/111g;Reducer HD : Φ68×45.2mm/218g; Spacer Ring SD81 : Φ57.5×22.5mm/18g; EX Tube 66 : Φ68×76mm/89g
Others SD Flattener and Reducer HD can be used with 52mm Filter

Shipping & Returns

Order Shipment:

If your order is in stock and we process the charges to your credit card, it will ship within five business days from the date of your order. We will send you tracking information within 24 hours of your order leaving the warehouse to the e-mail address you provided when checking out. If you do not receive tracking information from us within six business days of your order, feel free to follow up with us at

Cancellations & Refunds:

All orders canceled after 48 hours are subject to a $20 administration fee, whether or not your order has shipped. If your order has shipped, you (the buyer) will also be responsible for actual return shipping charges. Refunds will only be issued to the original credit card that you use when placing your order.


Please inspect the packaging of your item(s) when they arrive, if you notice any damage you should make note of it when signing for delivery. If your item(s) do arrive damaged, please send photos to and we will process an insurance claim on your behalf.

Price Match

We want you to spend your time focusing on the stars, not on the price.

If you find another online store that offers a lower price than us within six months of your purchase date please let us know and we will refund your original payment for the difference. We want you to feel confident that you are getting the absolute best price for the product you are ordering. If you find that our own website has a lower price for the same item you have ordered within six months of your purchase date, we will refund the difference as well.

To request your partial refund simply e-mail us a link to the same product on our website, or on our competitors website within six months from the date of your order and we will process the credit accordingly.

Our 100% Price Guarantee has some limitations:

  • You must purchase the item from our website before requesting your Price Match Guarantee
  • Promotions such as rebates and buy one, get one free offers are not eligible
  • The item must be in stock on the competitors website
  • The competitor must be an online store, they may not have a retail location
  • The website can not be a discounter or auction website (ie; eBay, overstock, etc..)
  • The competitor must be an Authorized Retailer of the product in question
  • The Price Match Guarantee includes the item price and the shipping charges, it excludes sales tax

Not convinced yet? Check out all our amazing products here!


Our Promise

We know you'll like the products we offer as much as we do- that's a Telescope Wolves Guarantee. In fact, if for any reason there is an issue with your products, please contact us upon receipt of your order with your order number and concern, and a member of our team will be happy to assist you from there.

Telescope Wolves will be happy to refund you the difference in price:
  • if you find another online store that offers a lower price than us within six months of your purchase date, OR
  • if you find that our own website has a lower price for the same item you have ordered within six months of your purchase date

Please consult our Price Match Guarantee for further details. 

Product Warranty Policies

We also offer warranties from each of our partners (to ensure that you enjoy the products as much as we do).

Vixen's Warranty :

Vixen warranties its products to be free from initial defects in materials and workmanship for a specified period based on part type:

  • Vixen Electronic Parts: Limited One Year Warranty
  • Vixen Mechanical Parts: Limited Two Year Warranty

Interested? Shop for all of Vixen's products here

Bresser's Warranty :

Bresser offers a limited USA one year warranty when product is registered within 60 days of purchase. Interested? Shop for all of Bresser's products here.

Explore Scientific's Warranty :

Explore Scientific offers a limited USA one year Warranty, which also converts to the Explore STAR Transferable Extended Life of the Product Warranty. Product must be registered within 60 days of purchase for this warranty to apply.

Interested? Shop for all of Explore Scientific's products here.

Daystar Filters's Warranty:

If used as directed, your DayStar filter is guaranteed for ten years. Should the filter become inoperative due to optical or mechanical failure, Daystar will repair the filter or replace it with an equivalent filter at no repair cost to the customer.

Under no circumstances shall a refund be issued:

  • due to application issues or the buyer's lack of skills in application of the product
    • Application of the DayStar product requires a degree of technical expertise specific to the exact product line, which is not common to other optical applications
  • if the product’s technical application procedures are NOT followed properly and poor results are yielded
    • Application procedures are posted on Daystar’s website and are stated in further detail in the client's operation manual
  • due to buyer’s remorse

Goods are warranted to be in operative, working condition as stated in specifications of product at the time of delivery. Should the goods not meet these specifications, Telescope Wolves will put a request in on your behalf to repair or replace the goods with items which meet stated specifications of product.

  • Goods shipped shall meet specifications stated by means of optical laboratory testing using independently verified spectrometer testing methods, visual inspection, and visual qualification of performance.

Interested? Shop for all of Daystar Filters's products here.

Hutech's Warranty:

Hutech offers a one year warranty on all its products.

Interested? Shop for all of Hutech's products here.


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Product Q&A


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