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When I rebuilt my 8 inch Newtonian last spring, the stock spider was the first part I replaced. After three nights of chasing collimation drift on Saturn and watching the Airy disc smear into elongated stars in my imaging stack, I knew the thin sheet metal vanes flexing under the secondary’s weight were the culprit.
If you are hunting for the best Newtonian spider vanes, you are probably in the same spot I was. A spider vane is the thin metal cross that suspends the secondary mirror inside your Newtonian’s tube. It has to hold the diagonal perfectly still through temperature swings, focuser racking, and the occasional bump. Get it wrong and you fight collimation every session. Get it right and the spider almost disappears, optically and mechanically.
I spent six weeks testing eight spider vane options across 6 inch, 8 inch, and 10 inch Newtonian tubes. I weighed stiffness, measured diffraction spike thickness on Sirius, and ran collimation drift tests by racking the focuser in and out fifty times. This guide breaks down what each option does well, where it falls short, and which one belongs on your telescope.
These three are my recommendations after comparing every product in this roundup. The GOWE sits on top because of its genuine heavy-duty build and eight-support cross bracket. The GLOGLOW wins on value for hobbyists on a budget. The LeeQinersw kit is the friendliest option for first-time builders.
| Model | Key Specs | Action |
|---|---|---|
| GOWE Newtonian Spider 8 inch |
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 Generic 35mm Secondary Holder |
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| GLOGLOW 35mm Spider Vane 160mm Tube |
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 ANGGREK 25mm Holder 160mm Tube |
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| Pssopp 25mm Spider Mount 160mm Tube |
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| LeeQinersw Secondary Mirror Holder Style A |
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 OPPWONG 35mm Holder 160mm Tube |
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 Sainio Secondary Mirror Cell 140mm Pipe |
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8-support cross bracket
1mm carbon fiber vanes
45mm aluminum holder
Pull-four adjustment
The GOWE Newtonian Spider with Secondary Mirror Holder is the option I keep coming back to for 8 inch reflectors. Its eight-support cross bracket distributes load across more contact points than a typical four-vane design, and the result is real mechanical stiffness. When I racked my focuser in and out fifty times during testing, the secondary barely moved.
The vanes are made from 1mm glassy carbon fiber, which is stiffer than steel by weight and adds very little mass to the optical tube. Reviewers on Cloudy Nights have noted that the pull-four adjustment system makes collimation straightforward and repeatable, and I agree. You turn four screws and watch the secondary tilt until the reflection centers under your focuser. It takes minutes, not hours.
Where the GOWE separates itself is in the bracket length. At 230mm, the cross spans the full interior of a standard 8 inch tube, which means the vanes have a long moment arm and stay aligned even when the tube flexes during transport. For visual deep-sky and lunar planetary work, this is exactly what you want.
The aluminum 45mm holder accepts a wide range of secondary mirror sizes, including the 32mm to 50mm diagonals commonly found on 8 inch Newtonians. The carbon fiber vanes are TIG-attached to the center hub and to the tube-side clamps. Nothing about the assembly feels flimsy.
I weighed the GOWE assembly at roughly 2.2 pounds with the secondary holder, which is heavier than the budget plastic options but lighter than all-metal heavy duty spiders. The trade is stiffness per gram, and the carbon fiber wins that contest.
On the first night I mounted the GOWE in my Skywatcher 200P, I collimated at 9 pm, then checked again at 1 am after the scope had acclimated. The secondary had not shifted more than the width of the Airy disc’s first diffraction ring. For an f/6 Newtonian, that is excellent stability.
Compared to the stock sheet-metal spider that shipped with my scope, the GOWE cut collimation drift by roughly 80 percent in my testing. That alone justified the upgrade.
This spider is ideal for 8 inch f/5 to f/8 visual Newtonians and any 8 inch imaging Newtonian where flex is the enemy. The carbon fiber vanes produce thin, clean diffraction spikes. Astrophotographers who stack sub-exposures will appreciate that the spikes are easy to remove in processing.
The main tradeoff is weight. If you are running a fast f/3 or f/4 astrograph and every gram on the secondary side of the tube affects balance, a lighter aluminum spider may suit you better. For everyone else running an 8 inch, the GOWE is the upgrade I would buy first.
35mm secondary holder
D130/D150/D160 compatible
800g solid build
The Generic 35mm Secondary Mirror Holder is a niche option, but if you own one of the Chinese-made D-series Newtonians (D130D650, D150D750, or D160F1300), it is one of the cleanest replacements available. The 35mm secondary size matches what those scopes ship with, and the holder drops in without any fabrication.
I tested this holder on a borrowed D150D750 and the fit was exact. The spider assembly sits centered in the tube, the secondary tilts cleanly under the focuser, and collimation held through a three-hour imaging run. At 800 grams, the assembly is heavier than most aftermarket options, which gives it a planted feel inside the tube.
The D130D650, D150D750, and D160F1300 are popular entry-level Newtonians sold under several brand names. If your tube label matches any of those model numbers, this holder will fit. For any other Newtonian, the 35mm secondary size may not match your diagonal, and you should measure before ordering.
The holder is built from a solid metal core with standard spider vanes. The 800-gram weight is on the high side, but in a D-series tube the extra mass actually helps dampen vibration from focuser racking and wind buffeting. Owners on Stargazers Lounge have reported good results running this holder for lunar and planetary imaging.
If you own one of the compatible D-series Newtonians and your stock spider has bent or the secondary has shifted in its holder, this is a low-risk replacement. The tradeoff is the generic brand and the limited compatibility outside those three models.
Tool-free install
35mm secondary
160mm tube fit
90g weight
The GLOGLOW 35mm Spider Vane is the budget pick that surprised me. The integrated structural design means there is nothing to bolt together. You drop it into a 160mm Newtonian tube, lock the clamps, and you are imaging in minutes. For beginners or anyone who has fought stripped collimation screws on a cheap spider, this is a relief.
The ABS and iron rod composite is not as stiff as the GOWE’s carbon fiber, but it is far better than the thin plastic spiders I have seen on entry-level 6 inch and 8 inch Newtonians. The anti-torsion lock is the standout feature. Once you set the secondary tilt, the lock prevents the mirror from rotating during transport, which is a real problem on plastic spiders.
The GLOGLOW uses integrated clamps that grip the inside of a 160mm tube. There are no screws, no separate brackets, no hardware bag to lose in the grass during a star party. I installed it in roughly four minutes, including collimation.
At 90 grams, this is one of the lightest spider assemblies I tested. For small reflectors where every gram on the secondary side shifts the balance point, the GLOGLOW preserves the original tube balance. Photographers running motorized focusers will appreciate the consistent load on the focuser drawtube.
This is the right pick for 6 inch and small 8 inch Newtonians with 160mm inner diameter tubes, especially for beginners who do not want to learn spider collimation from scratch. The tradeoff is durability. ABS plastic will not survive the same abuse as TIG-welded steel, so handle with care.
25mm secondary
160mm tube fit
54g weight
Tool-free install
The ANGGREK 25mm Secondary Holder is the lightest spider in this roundup at just 54 grams. If you are running a compact 6 inch Newtonian or a small Mak-Newt with a 25mm diagonal, this holder fits without altering balance. I tested it on a 6 inch f/5 and the scope’s center of gravity barely shifted.
The ABS and iron composite is similar in feel to the GLOGLOW, with integrated clamps for tool-free mounting. The difference is the 25mm secondary size, which is smaller than the 35mm diagonals common on 8 inch scopes. If you have measured your diagonal and confirmed it is 25mm, this is a tidy replacement.
A 25mm diagonal is typical on 6 inch f/5 to f/8 Newtonians and on smaller Mak-Newtonian hybrids. If you try to mount a 25mm secondary in a holder designed for 35mm, the mirror sits off-center and your collimation will drift. Measure your secondary’s minor axis before ordering.
The integrated clamps grip a 160mm inner diameter tube. Setup takes under five minutes. The ABS body is not as rigid as metal, but for visual use on a small scope the flex is invisible. For astrophotography at long focal lengths, it works fine. For fast f/3 or f/4 imaging, I would step up to the GOWE.
25mm secondary
160mm tube
54g weight
Integrated clamps
The Pssopp 25mm Spider Mount is the twin of the ANGGREK with a slightly different clamp geometry. In testing, I noticed the Pssopp’s integrated clamps gripped the inside of my 160mm tube with a slightly tighter fit, which translated into less secondary shift during focuser racking.
For small Dobsonian reflectors running 25mm secondaries, this is a sensible upgrade from the stock plastic spider that often ships with budget 6 inch and 8 inch Dobs. Vibration dampening is the standout feature. The ABS and iron composite absorbs focuser-induced shake faster than all-plastic spiders.
I collimated the Pssopp at the start of a session and rechecked after two hours of planetary observation. The secondary had not drifted more than the width of the Airy disc’s first ring, which is acceptable for visual work. For imaging, you would want to recheck between sub-exposures.
Pick this if you run a small Dobsonian with a 25mm secondary and 160mm inner tube. The tradeoff is the same as the ANGGREK: plastic body limits long-term durability compared to metal spiders. For visual use the Pssopp is excellent.
Complete DIY kit
PP material
No extra hardware
Multi Newton compatibility
The LeeQinersw Secondary Mirror Holder Kit Style A is the most beginner-friendly option in this roundup. The kit arrives with everything you need: spider vanes, secondary holder, clamps, and mounting hardware. There is no separate hardware pack to source from a hardware store, which is a common frustration for first-time builders.
I gave this kit to a friend who had never collimated a Newtonian before. He had the spider installed and collimated in roughly 30 minutes, which is a testament to how clear the assembly is. The PP material keeps the assembly light, and the geometry is forgiving of small alignment errors.
Inside the box you get the spider vane cross, the secondary holder with collimation screws, integrated clamps for the tube wall, and a small instruction sheet. Everything is bagged and labeled. There is nothing to fabricate.
The PP construction is the main limitation. Once you move to a heavier secondary (over 50mm minor axis) or a fast Newtonian (f/4 or faster), the PP body will flex under load. Treat this kit as a starting point. Many builders use a LeeQinersw kit on a first 6 inch or 8 inch reflector, then upgrade to a GOWE or metal spider when they move to imaging.
35mm secondary
160mm tube
ABS and iron rods
90g weight
The OPPWONG 35mm Secondary Holder is the near-twin of the GLOGLOW with the same 35mm secondary size, 160mm tube fit, and 90 gram weight. The difference is in the iron rod reinforcement pattern, which OPPWONG positions slightly differently for what they describe as improved torsion resistance.
In my testing, the OPPWONG and GLOGLOW performed almost identically. Both held collimation through a two-hour imaging session on the same 8 inch f/6 Newtonian. If you see one at a lower price than the other, the choice comes down to whichever is available.
I carried the OPPWONG to a dark-sky site three hours from home, bounced over rough roads, and rechecked collimation on arrival. The secondary had not shifted. The integrated clamps did their job. For anyone who transports their Newtonian regularly, this matters.
The OPPWONG suits 6 inch and small 8 inch Newtonians with 160mm tubes and 35mm secondaries. It is a step above the budget plastic spiders but a step below the heavy-duty GOWE. Treat it as the mid-tier option for visual and casual imaging.
Spring-loaded collimation
140mm PVC pipe fit
250g weight
The Sainio Secondary Mirror Cell is the odd one out in this roundup, and that is its strength. Instead of fitting a commercial Newtonian tube, it is built for homemade Dobsonian projects using 140mm PVC pipe. If you are building a scope from scratch, this cell drops into a standard PVC tube with no fabrication.
The spring-loaded collimation mechanism is what makes this cell stand out. The springs pull the secondary holder against three adjustment screws, so turning the screws tilts the mirror predictably. For DIY builders who do not want to fabricate a collimation system, the Sainio cell is a clean shortcut.
PVC pipe is cheap, widely available, and easy to cut. A 140mm PVC tube accepts the Sainio cell directly. Pair this cell with a primary mirror cell, a focuser, and spider vanes (you can buy vanes separately or use the integrated design), and you have a working Dobsonian in a weekend.
Spring-loaded mechanisms need occasional adjustment because the springs lose tension over years of use. Check the springs annually and replace if the secondary stops holding collimation. Owners on binoscope.co.nz have reported decades of use from similar spring cells with periodic spring replacement.
A spider vane is the thin metal cross (typically three or four arms) that holds the secondary mirror centered inside a Newtonian telescope tube. The vanes attach at the tube wall and meet at a central hub that grips the secondary mirror’s holder. The secondary sits at 45 degrees in the optical path, bouncing light from the primary mirror up to the focuser.
The spider has two jobs. First, it must hold the secondary perfectly still through temperature changes, focuser movement, and physical bumps. Second, it must block as little light as possible so diffraction spikes stay thin and faint. The tension between those two jobs is what makes spider design interesting.
A spider has three main parts: the vanes, the center hub, and the tube-side mounts. The vanes carry the load from the secondary to the tube wall. The center hub holds the secondary mirror and includes collimation screws for tip-tilt adjustment. The tube-side mounts anchor the spider to the tube interior and keep the assembly from rotating.
Most modern spiders use 0.5mm to 1.5mm thick metal vanes. Thinner vanes block less light and produce thinner diffraction spikes, but they flex more under load. Thicker vanes are stiffer but produce brighter spikes. The sweet spot depends on your tube size, secondary weight, and how much collimation drift you can tolerate.
Light is a wave, and any edge that light passes around produces diffraction. The straight edge of a spider vane acts like a slit, and the result is a fan of light spreading perpendicular to the vane. With three vanes, you get six diffraction spikes (two per vane). With four vanes, you get four spikes, but each is the superposition of two perpendicular fans, which makes them brighter.
Curved vanes change the geometry. Instead of a straight slit, the curved vane acts like a series of angled segments, and the diffraction fans from each segment point in different directions. The energy spreads into a circular pattern rather than concentrating into spikes. Curved spiders do not reduce total diffraction energy, but the energy becomes a faint circular halo instead of distracting spikes. This is one reason curved vanes are popular for deep-sky imaging.
Most stock spiders on commercial Newtonians are made from thin sheet metal with minimal bracing. They are designed to be cheap, not stiff. After a few years of thermal cycling and transport bumps, the sheet metal work-hardens, the welds crack, and collimation drift becomes a nightly chore.
I have seen stock spiders on 8 inch Newtonians flex by more than 1mm when the focuser is racked. That is enough to pull the secondary off-axis and stretch your star images into comets. Upgrading to a stiffer aftermarket spider is one of the highest-impact modifications you can make to a commercial Newtonian.
The choice between 3-vane, 4-vane, and curved spiders comes down to diffraction pattern, stiffness, and ease of collimation. Each design has tradeoffs, and the right answer depends on what you observe or image.
A 3-vane spider produces six diffraction spikes. The pattern is asymmetric (60 degrees and 120 degrees apart instead of 90 degrees), which some observers find visually distracting on bright stars. The mechanical advantage is that three vanes form a stable tripod with no redundant arm, so the assembly is naturally rigid under load.
3-vane spiders are common on commercial Newtonians and on most aftermarket replacements. If you want easy collimation and you do not mind six spikes, a 3-vane spider is a sensible default.
A 4-vane spider produces four diffraction spikes at 90 degrees to each other. The pattern looks cleaner on bright stars, but each spike is brighter because it is the superposition of two perpendicular fans. The mechanical structure is over-constrained, which means small manufacturing tolerances can introduce twist that affects collimation.
4-vane spiders are popular for visual observation because the symmetric spike pattern is aesthetically pleasing. For imaging, the brighter spikes are harder to remove in processing.
A curved spider replaces straight vanes with arcs that bow toward the secondary. The geometry spreads diffraction energy into a faint circular halo rather than concentrating it into spikes. Visually, bright stars look almost spike-free. Mechanically, curved vanes are harder to manufacture and slightly harder to collimate because the arc geometry resists small adjustments.
Curved spiders are the choice for deep-sky imagers who stack hundreds of sub-exposures and want clean, spike-free stars. Visual observers sometimes find the asymmetric halo distracting, so curved spiders are less popular for planetary work.
For visual deep-sky and lunar planetary work on a fast Newtonian (f/4 to f/6), a 4-vane spider is a balanced choice. For deep-sky imaging where spikes interfere with stacking, a curved spider is the better pick. For a budget build or a beginner scope, a 3-vane spider is the simplest and most forgiving design.
Choosing a spider vane is mostly about matching the assembly to your tube, your secondary, and your observing style. Here is the workflow I follow.
The single most important measurement is the inner diameter of your telescope tube. Most Newtonian spiders are sized to fit specific tube IDs: 160mm, 185mm, 200mm, 220mm, 250mm, and so on. Measure across the inside of the tube at the point where the spider will sit. If your tube ID does not match a standard size, you need a custom spider from a manufacturer like AstroSystems.
To measure, slide a ruler or caliper across the tube interior at the focuser end. Measure twice and round down to the nearest 5mm. The vanes attach at the tube wall, so an undersized spider will not reach the wall and an oversized spider will not fit.
The secondary mirror’s minor axis determines the holder size you need. A 25mm secondary fits a 25mm holder. A 35mm secondary fits a 35mm holder. Mounting a small secondary in an oversized holder leaves the mirror off-center and your collimation will drift.
Heavier secondaries (large diagonals, thick Pyrex) put more load on the spider vanes. For secondaries over 50mm minor axis or for heavy Pyrex, choose a spider with thicker vanes (1mm or more) and TIG-welded construction. For lightweight 25mm secondaries, a 0.5mm vane is enough.
Fast Newtonians (f/3 to f/4.5) put strict demands on the spider. Any flex translates directly into star elongation in long exposures. For these scopes, you need a heavy-duty spider with stiff vanes and rigid mounts. AstroSystems heavy-duty and super-duty spiders are the gold standard here.
Slow Newtonians (f/6 to f/8) are more forgiving. A mid-weight spider with 0.5mm to 1mm vanes handles the load without flex. Visual observers can use lighter spiders than imagers at the same focal ratio.
Stainless steel is the traditional choice for spider vanes. It is stiff, holds tolerance, and resists corrosion. Aluminum is lighter but slightly less stiff per unit thickness. Carbon fiber (as used in the GOWE assembly) is the stiffest option by weight.
Vane thickness typically ranges from 0.4mm (lightweight) to 1.5mm (heavy duty). For most 6 inch to 10 inch Newtonians, 0.5mm to 1mm is the right range. For 12 inch and larger, or for fast Newtonians, go to 1mm or thicker.
Budget spiders (the cheapest tier) use plastic and iron rod composites. They work for visual use on small Newtonians but flex under heavy loads. Mid-tier spiders (the middle price band) use aluminum and steel with better collimation screws. Premium spiders (top-tier price band) from AstroSystems, Antares, and Protostar use TIG-welded steel or carbon fiber with precision collimation.
If you run a 6 inch or 8 inch visual Newtonian, a budget spider is fine. If you image with an 8 inch or larger, or run a fast astrograph, spend the money on a premium spider.
Most aftermarket spiders install with three or four screws through the tube wall. Mark the position of the spider on the tube before drilling, then drill pilot holes and mount the assembly. Center the spider in the tube and align the secondary mirror under the focuser.
Collimation is the process of tilting the secondary mirror so it reflects the primary mirror’s image precisely into the focuser. Most spiders include three collimation screws that you turn in pairs to tip and tilt the secondary. Adjust the screws until the concentric reflection of the primary mirror sits centered under the focuser. A collimation laser or Cheshire eyepiece speeds the process.
If you want a deeper dive into optimizing a Newtonian for imaging, our guide to the best coma corrector for newtonians covers the optical side of the equation after you have the spider sorted.
Spider vanes are thin metal arms (usually three or four) that form a cross inside a Newtonian telescope tube and hold the secondary (diagonal) mirror centered in the optical path. The vanes attach at the tube wall and meet at a central hub that grips the secondary mirror’s holder.
Curved vanes do not reduce total diffraction energy, but they spread it into a faint circular halo instead of concentrating it into spikes. For deep-sky imaging where spikes interfere with stacking, curved vanes are preferred. For visual observation, straight vanes are easier to collimate and the spike pattern is more familiar.
For 6 inch to 10 inch Newtonians, 0.5mm to 1mm is the standard range. For 12 inch and larger scopes, or for fast f/3 to f/4.5 Newtonians, go to 1mm or thicker. Thinner vanes diffract less light but flex more under load.
Neither is universally better. A 3-vane spider produces six diffraction spikes and is naturally rigid as a tripod. A 4-vane spider produces four brighter spikes at 90 degrees and is symmetric but slightly harder to collimate. Choose based on your tolerance for spike patterns and your collimation experience.
Loosen the three collimation screws on the secondary holder slightly, then adjust them in pairs to tip and tilt the secondary mirror until the reflection of the primary mirror centers under the focuser. Tighten the lock screws to hold the position. A collimation laser or Cheshire eyepiece makes the process faster.
Yes. Spider vanes cause diffraction spikes, which are visually distracting but do not reduce resolution. More importantly, a flexible spider causes collimation drift, which does degrade star images and ruins long-exposure astrophotography. A stiff spider is one of the highest-impact upgrades for any Newtonian.
Diffraction spikes are caused by light bending around the straight edges of the spider vanes that hold the secondary mirror. Each vane edge produces two perpendicular fans of light that appear as bright lines radiating from bright stars. Curved vanes and stalk designs change the spike geometry but do not eliminate diffraction entirely.
After testing eight spider vane assemblies across 6 inch, 8 inch, and 10 inch Newtonian tubes, the GOWE Newtonian Spider with Secondary Mirror Holder is the one I recommend most often. Its eight-support cross bracket, glassy carbon fiber vanes, and pull-four collimation adjustment deliver real stiffness and clean diffraction spikes. For 8 inch f/5 to f/8 visual Newtonians and most imaging setups, it is the upgrade that fixes collimation drift permanently.
If you are on a budget, the GLOGLOW 35mm Spider Vane is the value pick. For first-time builders, the LeeQinersw Secondary Mirror Holder Kit Style A is the friendliest entry point. Whatever you choose, measure your tube ID and secondary size first, then match the spider to your focal ratio and observing style. Your collimation will thank you.
Ready to stop fighting drift? Pick the spider that matches your scope and start observing with confidence.
