3" Rack & Pinion Focuser. 00 Select options. FOA-60 Ortho Apochromatic Refractor. 5" Focuser) As low as $8,198. ر. 3″ Rack & Pinion Focuser ($2000) This is a good example of an APO refractor that is designed and packaged primarily for the Astrophotography market. William Optics Fluorostar 91 — Combines a compact design with remarkable imaging capabilities. Zenithstar 73 III APO . The three-element optical design features a 91mm aperture using FPL-53 glass. New. William Optics. New for 2021 - William Optics Fluorostar / FLT 91 An Apochromatic triplet refractor for visual astronomers and astrophotographers who want very high performance from a midsize telescope. 30 ₹ 4,310. AstroBin is an image hosting platform and social network for amateur. 3 shares. Wish List Compare. → Refractors. 00. The STM-coatings and superb quality provide excellent optical performance and unmatched value. The features of the Fluorostar 91 RotoLockWilliam Optics Fluorostar 91 FPL53 Triplet APO Refractor with 3. More than a playlist. To see how to install the Flat6Aiii including the correct back focus go to the following link:two flatteners/focal reducers is like having two telescopes with different focal lengths. 00. There's an initial grub screw to remove which will them expose the screws holding the gauge to the shaft. 6lbs) including tube rings and dovetail plate. As low as $4,378. Fluorostar 120. 3" R&P Focuser. 00. Specifications general. skysurvey, on 15 Nov 2020 - 06:16 AM, said: No, the WO 91 Fluorostar isn't any cheap but I have no idea why, IMO we are talking about a 2515€ telescope and about a 1382€ telescope that are the same, don't let you that 1mm of difference confuse you. Wish List Compare 【Refurbished】Gran Turismo 81 IV-Space Grey . A-F120. 91mm. Toll-Free: +1-800-504-5897. Add to Cart 3 in stock Yes, our inventory is accurate! See It In Person - On Display In Our Showroom!. • Flexible installation for use on a variety of refractors, Newtonians, schmidt cassegrain and other Optical TubeWilliam Optics Fluorostar 91 / FLT91 Imaging Cameras QHYCCD QHY268 Pro M Mounts Software Bisque Paramount MX+ GEM Filters Chroma Blue 36 mm · Chroma Green 36 mm · Chroma H-alpha 3nm Bandpass 36 mm · Chroma Lum 36 mm · Chroma Red 36 mm Accessories William Optics Flat6A III SoftwareWilliam Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI2600MC Pro Mounts Celestron Advanced VX Filters Optolong L-eNhance 2" Accessories William Optics 0. 0 Mono ZWO 36mm Ha, SII, OIII 7nm. T-FLT-91-SG-Refurbished. Release Date 08/19/2015 11:49:39 AM. The William Optics FLT 91 is the perfect apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. The fluorostar 91 with the 0. 9 & GH5. add to list. 00 Original price. 56% Hot. 00 - $2,897. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright. add to list. Product Details. QC issues described here are something that one would not expect from such established producer. I have heard William Optics FLT 91 Fluorostar is one of the best optic refractors of its league. Qty. William Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI2600MM Pro Mounts ZWO AM5 Filters Optolong H-Alpha 3nm 2" · Optolong OIII 3nm 2" · Optolong SII 3nm 2" Accessories William Optics Flat68 III · ZWO ASIAIR Plus · ZWO EAF · ZWO EFW 5 x 2" Software Pleiades Astrophoto PixInsightWith a focal length of 478mm, this f/5. Or fastest delivery Thu, Nov 16. The new William Optics Fluorostar FLT 91 is a three element air-spaced apochromatic refractor with a focal ratio of f/5. William Optics. William Optics RedCat 51 (Unboxing) 0:16. Be the first to review this product . 2019 All New Slide-base 50mm UniGuide Scope (with a Unique 1. 1. William Optics Fluorostar 91 / FLT91 Imaging Cameras QHYCCD QHY183C Mounts iOptron CEM26 Software Pleiades Astrophoto PixInsight · Russell Croman Astrophotography BlurXTerminator · Russell Croman Astrophotography NoiseXTerminator · Stefan Berg Nighttime Imaging 'N' Astronomy (N. add to list. How to install the ZWO EAF on the William Optics Fluorostar 91. Lens Type Apochromatic Triplet Prime Lens Focal Length 540mm Diameter 91mm Aperture f/5. 99. The thing you can immediately notice is the smaller overall FWHM (2. 2y. 35%. 00. I’m on the verge of purchasing a new refractor, I currently have an EQ6 R pro, a SkyWatcher 200 PDS and a Canon R6. 6M subscribers in the astrophotography community. GE OEC Fluorostar Arco em C móvel digital Manual do Operador a partir de S/N 10,000 Refª N. Wish List Compare. ขายกล้องดูดาว William Optics Fluorostar 132 F/7 OTA Red ในราคาที่คุณถูกใจ. 18, 20221. Sale price. Page 2 of 23 - WO Fluorostar 91 - new scope - posted in Refractors : The longer I wait, the more on the fence I find myself. “続いて> FLT-91鏡筒とセットでおすすめなのがフラットナーレデューサー”FLAT6AIII”. Our Price: $1,998. Mount: Sky watcher EQ6R-pro. 72) Filter: Chroma 36mm HA 3nm Telescope Filter - Unmounted; Filter: Chroma 36mm OIII 3nm Telescope Filter - Unmounted; Mount: Sky-Watcher EQ6-R Pro (Used iOptron Tri-pier with Adapter 8036-TK)The William Optics Fluorostar 91 is the perfect Apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. WO Fluorostar 91 - new scope. Imaging camera: ZWO ASI294MM Pro. I have an 8 scope sitting by my star adventurer, and I havent used it once. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright. Comment. So, if you have a filter that is 3mm thick, you need to add 1mm of spacing to your imaging train to retain the correct back focus. I have a Redcat 51, a Zenithstar 73, and a Fluorostar 91. not quite sure on the purpose, FLAT in the name makes me think it's a flattener? DSLR Attachment - William Optics 48mm T-Ring for Canon EOS - I'm guessing I need something else to complete connection to the telescope. The features of the Fluorostar 91 RotoLock William Optics Fluorostar 91 FPL53 Triplet APO Refractor with 3. Page 1 of 2 - William Optics Fluorostar 91 Focuser Issue - Response from WO themselves. I do however, use their instruments for astrophotography and so I was surprised by the general feedback regarding their newly released. 77 degrees (see scope mounted, Version B). Page 14 of 23 - WO Fluorostar 91 - new scope - posted in Refractors : Got my EAF last Friday and installed it on the new WO FTL91 and took it out for another spin. 8x reducer is almost identical FOV as the Zenithstar was, but gathers more light and faster, and the Zenithstar was not as good as the Redcat anyway. Telescope: Fluorostar 91 APO / Fluorostar 132 / Takahashi FC-100 Or something in this category up to 10-12k EUR Mount: ZWO AM5 Mount / ZWO TC40 Carbon Control:. Product Details. 6. 00. Add to Cart. 4 Reviews. 7. You're reviewing: FLAT6AIII special edition for Fluorostar 91. Vendor William Optics Regular price $1,998 Sale price save $-1,998 Unit price / per . 00. The three-element optical design features a 91mm aperture using FPL-53 glass. 9 and a focal length of 540mm. Remove the temperature gauge off the telescope. Had to fiddle with the installation as I ended up putting the mount screws into one of the focusing tighteners and so it wasnt able to focus, but once Id figured that out and used the different mounting holes on the bottom of the. 16, 2023 · Feb. 8 focal reducer, which brings the FLT 91 to a focal length of 432 mm at f/4. Its always a shame to take off the visual back on these. I can only see that the WO has a better focuser (not too much) and a thermometer, other than. Everest Systems LLC has officially launched a new, high-performance and field-applied topcoat under the Fluorostar brand name for restoring and protecting multiple types of roofing surfaces with long-lasting color. View as Grid. 9 Focuser Dual Speed 3. Fluorostar 91 Trailer. Price jumps out as the obvious difference $3210 vs $1999 though availability and color might be a consideration. Sky-Watcher Explorer 130PDS 12. Brands / Companies 910 ; Cameras 3302 ; Sensors 465 ; Telescopes & lenses 3721 . Now Only $1,398. · 151 views. Technical Specifications. The Fluorostar 120 is a Three Element Designed APO refractor. Filter: Chroma 36mm OIII 3nm Telescope Filter -. In stock. The STM-coatings and superb quality provide. William Optics manufactures Refractor telescopes, binoculars, digital camera adapter lenses for telescopes, eyepieces, diagonals and other accessories. The Zone at 91-3, Victoria, British Columbia. 4. Providing the supreme visual and photographic performance astronomers expect from a medium sized telescope, the William Optics Fluorostar 91 f/5. In Stock. 0. Can I really justify dropping ~$3,000 for 2 scopes? (I am expecting the Fluorostar 91 to be around $2,000 and the Redcat 71 around $1,000) Product Q&A. Wish List Compare. Coupled with my ZWO ASI1600 MM Pro, the field of view is 2. Fluorostar 91. / per. Focal Length: 540 mm. Guide Star 61 (Soft Carry Case included) As low as $438. Page 1 of 2 - Askar FRA500 vs the WO FLT 91 - posted in Refractors : Looking at these two scopes. Mounting Rings;Telescope/Lens: William Optics Fluorostar 91 (540 mm at f/5. As low as $1,998. 00. Telescope/Lens: William Optics Fluorostar 91 (540 mm at f/5. These corrective optics work best at a specific distance away from their glass elements, most commonly 55mm. $2,494. The estimated age of M48 is 300 million years. The confused or confusing information that WO puts out re 68III backfocus is unhelpful as has been noted. William Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI533MC Pro Mounts ZWO AM5 Filters Antlia ALP-T Dual Band 5nm 2" Accessories William Optics Flat68 III · ZWO ASIAIR Plus Software Aries Productions Astro Pixel Processor (APP) · Pleiades Astrophoto PixInsightWilliam Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI294MC Pro Mounts iOptron CEM70 Filters Optolong L-Ultimate 2" Accessories Primaluce Lab EAGLE4 Software Pleiades Astrophoto PixInsight Guiding Telescopes Or Lenses William Optics UniGuide 50 Guiding Cameras ZWO ASI120MM MiniTakahashi FSQ-106EDP · William Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI2600MC Pro Filters Optolong L-Pro 2" Accessories Takahashi 645 Reducer QE 0. William Optics Fluorostar 91 by William Optics. 9 Fluorostar. SKU. If your camera chip is too close or too far away, then the elements will not actually perform their intended corrections. The back focus is a critical spacing that must be obtained if one is using a Flattener or Reducer. 00. HOUSTON — Everest Systems LLC has officially launched a new, high-performance and field-applied topcoat under the Fluorostar brand name for restoring and protecting multiple types of roofing surfaces with long lasting color. Add to Cart-23. Diameter. The nebula is located in the central-southern part of the constellation, about 5 ° north of the star ζ Cephei. 5) Reducer/Flattener: William Optics FLAT7A (624mm at F/5. Retracted Length. Special thanks to Agena Astro for get. Arriving in a single box, the William Optics Fluorostar FLT 91 was protected in a robust and well-padded soft carry case. Fluorostar series; Gran Turismo series New; ZenithStar series; Guider series New; Finder series; Binoculars; Eye Pieces. My review of the William Optics Fluorostar 91 APO Triplet and some exciting news from the AstroWorld TV team! Visit my Astrobin page for Hi-Resolution images. Incredible numbers. 5 Items. Write Your Own Review. I can only say that Esprit owners seem well satisfied and and the same is true of Willams Optics scope owners. Nickname. 00. The FLT 91 is the perfect Apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. Im excited. My first YouTube video! Watch as I unbox the William Optics Fluorostar 91 and give my initial thoughts and impressions. Vendor. If they were just sourcing and retailing scopes like some other brands, I'd expect to be able to easily find equivalents to, say, the RedCat 71 or the Fluorostar 91. : +1-847-513-6201. What made this project so difficult was the abundance of stars in the region. The FLT 91 is the perfect Apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. 9 and reduces to f/4. 00. Use a dust cover or a soft cloth to cover the telescope and protect it from dust. Here is my FLT 91/Reducer combo with a 2600MC, so the chip is bigger and the pixels are smaller, both of which put a larger strain on the optics. And attached is a FWHM-Eccentricity analysis of the luminance data. I have it, and the optics are great, but the mechanics has sag and tilt. Basic Information: Telescope: William Optics FLT 91 with FLAT 6AIII reducer. 7) / GTF102 : Telescope or lens: 3: 20: William Optics Gran Turismo 102 / GT102 : Telescope or lens: 22: 345: William Optics Gran Turismo 153 / GT153 :ウィリアムオプティクス社 Fluorostar 91mm3枚玉 FPL53アポクロマートレンズの新鏡筒優れた光学設計によりストレールレシオ95%以上を達成しております[有効径] 91mm[焦点距離] 540mm(F5. I was also lucky enough to find the 0. The three. In Stock. Not managed to use my new FLT 91 yet, still waiting to source a Skywatcher EQ6 R Pro mount. The FLT91 Fluorostar lens is designed to be compatible with various camera mounts, including Canon EF and RF, Nikon F and Z, Sony E, Pentax K, Micro 4/3, and Fuji X T-Mounts. Hope you enjoy the image! Happy Holidays! The Soul Nebula is sometimes also known as the Embryo Nebula or IC 1848, which is an emission nebula located in the constellation Cassiopeia. 813. Both set ups look attractive and suitable to my needs. Hours of Operation. 00 Regular Price $1,568. 00 Regular Price $1,568. That is just about the limit of the sky, guiding and diffraction limit for a 91mm aperture. William Optics FLT 91 Fluorostar 91mm f/5. Main Equipment, not all are listed here. Add to Cart. Like. The FLT132 is a different beast in terms of weight for a mount 3-4kg might not seem much but it is the moment of the arm that counts and that makes refractors more difficult to mount well. 8x reducer is almost identical FOV as the Zenithstar was, but gathers more light and faster, and the Zenithstar was not as good as the Redcat anyway. Optional. Only 1 Left!William Optics Flourostar 91 with 3. William Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI2600MM Pro Mounts ZWO AM5 Filters Optolong H-Alpha 3nm 2" · Optolong OIII 3nm 2" · Optolong SII 3nm 2" Accessories William Optics Flat68 III · ZWO ASIAIR Plus · ZWO EAF · ZWO EFW 5 x 2" Software Pleiades Astrophoto PixInsight Guiding Telescopes Or Lenses. 00 My account / Register. f/5. The W-O web site for the Flat 68 iii shows the back focus for the FLT91 as 75 mm, but also indicates the adjustment distance for a DSLR or mirrorless camera as 5 mm. 00. Cloudy Nights. SKU. Optional. The deep-sky imaging performance of that little APO is what. Page 11 of 23 - WO Fluorostar 91 - new scope - posted in Refractors : Thats with the WO reducer for this scope and a QHY268. SWAN 2" SWAN 1. That, or purchase a new. 4mm This William Optics 2" Field Flattener and Reducer has been designed to optimize the flat-field iMost of their scopes don't appear to have counterparts with any other manufacturer. 9) Flattener/Reducer: FLAT6AIII special edition for Fluorostar 91 (432 mm at f/4. CLOSED: Thanksgiving, Christmas Day, New Year's Day. Then, put the bracket in place and use the M3 screws and washers in the spots where the others were just removed. WILLIAM OPTICS FLT 110 APO f/7. 61 pixel). The FLT has FPL53 glass and the years of great reputation of William Optics build quality. The STM coatings and superb quality provide excellent optical performance and unmatched value. 4mm. William Optics. 8 triplet on its website. Regular price $1,998 3 in stock View. I have since added another 1. Add to Cart. Made with CNC. Add to Cart. For the William Optics . RotoLock Adapters; Camera / T-Mount Adapters; Mounting. 00. 9. It is similar to the Gran Turismo series, and at present it comes in apertures of 91mm at f/5. The STM-coatings and superb quality provide excellent optical performance and unmatched value. Gran Turismo 81 IV. Mount: EQ6R-Pro. William Optics offers another model of apochromatic triplet refractor, the Fluorostar. William Optics Fluorostar 91 APO - Gold. Sort By. A soft carry case comes standard with the William Optics Fluorostar 91. 8x reducer (6Aiii), you must be 62. Vixen Dovetail Adapter for William Optics RedCat. Optolong L-Pro 2" 1 10. The flattener can be securely screwed on to the focuser. FLAT6AIII special edition for Fluorostar 91. Now Only $1,498. View listing photos, review sales history, and use our detailed real estate filters to find the perfect place. buy DETAILS. Series: FluoroStar . The Esprit+EQ8 are probably a "handful" in terms of handling, but I have seen people use it in they backyard without a permanent installation. Reviews. 86 shipping. Page 19 of 22 - WO Fluorostar 91 - new scope - posted in Refractors : Soon after I had purchased my 91mm I had added a 2nd WO Losmandy bar at the top, and then mounted the slide base for the guidecam on top of the dovetail. Handle for twin-monitors Fluorostar. Other suggestions welcomed. William Optics Fluorostar 91 / FLT91 Imaging Cameras ZWO ASI2600MM Pro Mounts iOptron CEM70 Filters ZWO Blue 36 mm · ZWO Green 36 mm · ZWO H-alpha 7nm 36mm · ZWO O-III 7nm 36mm · ZWO Red 36 mm · ZWO S-II 7nm Accessories William Optics Flat68 III · ZWO EAF · ZWO EFW 7 x 36mm SoftwareWilliam Optics Fluorostar 91 / FLT91 4 49. View full description. Pixel scale looks good with my 533 MC Pro, should frame some of the DSO's nicelyWilliam Optics Mortar三脚用 赤道儀接続アダプター タカハシP-2赤道儀用The William Optics FLT 91 is the perfect apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. 00 Shane23 #. When I looked at the fov it matched the Esprit 100ED I was also looking into buying for imaging. Not that this was with a 2. Pending edit 1; Mounts 604 ; Filters 2231 ; Accessories 1396 ;Language: English. 1113. There are a few superficial scratches on the tube but the optics are great. Despite being only a little longer, that diameter and extra glass means this is much heavier than my Z73. William Optics Fluorostar 91 APO - Gold. Add to Cart. As low as $933. It is part of the large star-forming region of the Cepheus molecular nebula complex. The three-element optical design features a 91mm aperture using FPL-53 glass. The three-element optical design features a 91mm aperture using FPL-53 glass. Special Edition FLAT6AIII Adjustable Reducer / Flattener for William Optics Fluorostar FLT 91 Telescopes. - William Optics Fluorostar 91 - William Optics 6AIII 2" x0. ر. 25" inch RedCat Erecting Prism - Silver Version (for RedCat 51 only) $137. 1 year warranty. 03 Add to cart; Sale! New Cat Series Saddle Handle Bar ₹ 5,310. It is an active star-forming region, home to many young, hot stars that are still in the process of forming. Kingfisher Shot on WILLIAM OPTICS Redcat 51 250mm f/4. txt) or read online for free. 900. April 14, 2023. Fluorostar 91 APO Triplet Refractor. $656. (Pre Order)New Fluorostar 156 (With Feather Touch 3. Qty. Putting the motor in place should be obvious at this point. 00. This is a NEW listing. doc 3Version 1. New Gran Turismo 81 (discontinued) Details. The deep-sky imaging performance of that little APO is what. 3″ Rack & Pinion Focuser ($2000) This is a good example of an APO refractor that is designed and packaged primarily for the Astrophotography market. 8x reducer (6Aiii), you must be 62. ع. Im having trouble finding honest reviews on the Fluorostar 93. New for 2021 – The FLT 91 is the perfect Apochromatic refractor for visual and photographic astronomers demanding excellence. Part number Ganymedes: WO-A-F120GD-RP33 . Unfortunately, I was not able to get the focus right. Its always a shame to take off the visual back on these. Specifications product. My current SW 100ED APO is a fine scope but as I tend to be a "grab n go" kind of guy, the shorter tube of the FL 91, mounted on my Porta II really appeals to me. Telescope/Lens: William Optics Fluorostar 91 (540 mm at f/5. Fluorostar 91 Trailer. Im having trouble finding honest reviews on the Fluorostar 93. WANT! 2y. about 8 hrs of data over 2 nights. 8x Flattener/Reducer APO · ZWO ASIAIR Plus SoftwareWilliam Optics Fluorostar 91 / FLT91 Guiding Cameras ZWO ASI174MM Mini Acquisition details Dates: Feb. Extended Length. As low as $1,998. Astronomers desirous of superb visual and photographic intermediate sized refractor performance will much appreciate the William Optics 91 mm f/5. 30 Add to cart; Sale! Fluorostar 91 APO ₹ 203,103. STAR 91 Ml 21 SPECIFICATION M92 M92 M83 Focal Length : 540mm Diameter : 91 mm Aperture : f/ 5. 34 degrees X 1. I'm testing out a new scope and flattener/reducer. Fluorostar 91 Trailer. Transfer easily. (Pre Order)New Fluorostar 156 (Innovative Bahtinov Mask Cover (Patented) included) As low as $7,398. Id like to think Ive come up to speed fairly quickly on. The STM coatings and superb quality provide excellent optical performance and unmatched value. skysurvey, on 15 Nov 2020 - 06:16 AM, said: No, the WO 91 Fluorostar isn't any cheap but I have no idea why, IMO we are talking about a 2515€ telescope and about a 1382€ telescope that are the same, don't let you that 1mm of difference confuse you. Unit price. Dielectric Coating Diagonals; Erecting Prisms; Accessories. I have since added another 1. The William Optics FLT 91 is the perfect apochromatic refractor for visual and photographic astronomers demanding excellence in a midsize telescope. Hope that WO reads related threads here and strive to improve. Business, Economics, and Finance. Using the appropriate T-Mount and T-ring, users can create a functional imaging setup with the FLT91. Swap to the smaller Allen key and with a torch find the two screws at 45 degrees so just rotate the focus adjuster to see them. RotoLock Adapters; Camera / T-Mount Adapters; Mounting. William Optics Fluorostar 91 Imaging Cameras ZWO ASI2600MC Pro Mounts iOptron CEM40 Accessories ZWO OAG · ZWO ASIAir Pro · William Optics Flat6AIII Software Astro Pixel Processor · Pixinsight 1. As low as $1,998. De foto is van een FluoroStar 91 en dient alleen als voorbeeld voor de kleur. I recently removed the dovetail on top and put back in place the guide bar to its original setup the way the scope. William Optics. View full description. WO Fluorostar 91 - $2k and similar focal length as my 80mm. The Zenithstar 103 has been discontinued. Intl. printed 14-Aug-15 89 Rendered PDF File Page 91 of 125 DOC1426760, Rev:3. We were immediately impressed with the quality of the case and how securely the telescope was supported inside. 9 APO Triplet Refractor Telescope FPL-53. William Optics Fluorostar 91 APO - Red. Scribd is the world's largest social reading and publishing site. 17Kg. Zygo Test Report + $99. The STM-coatings and superb quality provide excellent optical performance and unmatched value. Look no further than Bintel, where we endeavor to provide high quality service and after-sales support second-to-none! We stock a wide range of great telescopes and have been supplying amateur astronomers in Australia for over 30 years. 9AM-5:30PM CT Mon-Fri. View full details Original price $2,697. 00 Color. 1 65kg (OTA only) 1 2. Aviation Museum. Wish List Compare. Both the Fluorostar 91 and Redcat 71 are dropping in the December/January time frame. Add to Cart. Fluorostar 91 APO Triplet Refractor. 8x Reducer / Flattener William Optics 2019 Slide Base 50mm Uniguide Scope Skywatcher AZ-EQ6GT Mount & Tripod ZWO ASI290Mini Mono Guide Cam ZWO ASI Air Pro ZWO 5v Electronic Focuser ZWO ASI1600mm Pro USB 3. FLT-91 / Flat 68iii elongated stars? - posted in Experienced Deep Sky Imaging: First light on my W-O Fluorostar 91 / Flat 68iii, and could use some advice. 250 180 second exposures. Regular Price $1,998. 900. Wish List Compare. The latest scope in the FLT series is the Fluorostar 91. Details. I just purchased a William-Optics Fluorostar 91 telescope and Flat 68 iii field flattener, and have a question about connecting a ZWO ASI 533 MC Pro camera. At this point you could technically say you're done, but I also saw a recommendation to se the FLT91's focal length to 21mm as a rough start point.