Meade Lightbridge Observing report as of 25.4.2009

[Doc]

25.4.2009

Meade Lightbridge 16" F4.5 FL 1829mm

No Moon

Seeing Mag 4.2

One of the neighbours opposite our house decided to have a barbeque and rather annoyingly used the security light to illuminate things so my session didn't begin until 23.00 when the barbeque finished.

Started the night off with a distant globular cluster in Coma Berenices called M53, it's about mag 7.7 and 62,000 light years away. My 21mm at x 87 showed quite a few resolved stars but the clusters core stayed intact. A very pleasant sight indeed.

Staying in Coma Berenices I moved the scope upwards roughly 5 degrees and came upon the M64. This is the famous Blackeye Galaxy. It has also been called the Sleeping Beauty Galaxy. The distance of this galaxy is not very well known, but best guesses place it at around 20 million light-years from Earth. At a surface magnitude off 12.7, the galaxies shape was very easily seen and it's core was very evident. I observed this with many eyepiece combinations and the 21mm at X 87 gave me the best results.

Hercules was now getting higher so off course the first point of call was M13 the finest and most well known globular cluster in the Northern hemisphere. It originally was discovered by Edmond Halley in 1714. It is about 25,000 light-years from us, and has an impressive diameter of about 150 light-years. Through the 21mm Hyperion it is just amazing. M13 easily resolves most of it's outer stars but the core remains intact. In the 8mm hyperion at x228 I got the feeling I was actually inside the globular cluster, I saw stars everywhere right out to the edges off my FOV. The core was easily resolved. Best view off this mighty cluster I have ever had.

Another Globular Cluster in Hercules is the M92. This cluster is located about 26,000 light-years from Earth and has a diameter of around 85 light-years. It is believed to be around 16 billion years old and is approaching us at a rate of 112 km/sec. The 21mm at x 87 easily resolved 40 stars but the 12.5 Ortho at x146 easily reolved 60 stars but the core stayed intact but it was a lovely sight.

Staying in Hercules I hunted down another Globular Cluster this time called NGC6229. Last time I looked I couldn't find this one but after about 10 minutes I found it. It's a very small cluster approx 3.8'x3.8' and shines at a undisclosed surface brightness. I found this in my 21mm Hyperion and with this eyepiece no stars were resolved. Even in the 8mm at x228 no stars were resolved.

Staying in Hercules I went hunting for a planetary nebula known as NGC6210. This was incrediblly hard to find, I tried all the methods I know but eventually I found it. Very small indeed 0.3'x0.2' and looked exactly like a star in my 32mm Tal at x57 . In the 21mm Hyperion it appeared as a blue circular non stellar object just a tad bigger then a large star. No details were made out in any off my eyepieces right down to my 6mm ortho at x 304 . But this was still a very impressive sight.

While in Hercules I tried to find Abell 39 or PK47-42.1 a planetary nebula but even though I was in the right area I could not detect at. Maybe a O111 filter is needed on this one.

Lyra was now in view so I headed for one of my favourites the M57 the Ring Nebula. It is probably the finest example of a planetary nebula anywhere in the sky. It was formed when a star about the size of the Sun neared the end of its life cycle and shed its outer shell of hydrogen gas. This shell of material is illuminated by the remains of the star, known as a white dwarf, in the center. The nebula is well known for its beautiful colours, ranging from red to yellow, green, and blue. Its age is estimated at about 5,500 years.

Its distance from Earth is not very well known. In my 21 mm hyperion M57 looks like a near eliptical grey with a slight green tint smudge against the black background. Putting in my trusty 8mm hyperion the donut shape becomes very evident. The blackness inside the donut becomes visible but no central star appears. Apparently the centre star is Mag 13 so should be within my grasp, but tonight it was not evident.

Next I decided to sweep over to Serpens Caput and hunt down the M5 as this is a new object for me. It is believed to be one of the oldest of the globular clusters, at an age of about 13 billion years. M5 is located about 23,000 light-years from Earth, and has a diameter of about 130 light-years. In my well used 21mm hyperions I could easily detect the globular cluster it seemed to appear like a little M13. With this eyepiece I counted 40 stars on the outside of the core. With the 12.5 ortho at least 60, but with the 6mm ortho I was submerged inside the core. So many stars it was impossible to count, this was a sight to remember.

Next over to the area at the top of Cygnus and just swept over this and looked at a few open clusters. This area is awashed with stars, so many of them all different sizes and colours I visited NGC6791 a lovely loose cluster, so many mag 7 stars and a very bright star within it called Theta Lyra.

Next over to NGC6866 a modest cluster of about 40 stars, nothing special in this one but still nice to observe.

Next onto NGC6811 a wonderful open cluster in Cygnus. Looks like a loose rendition off the famous double cluster, with one side as bright as mag 6 the other side mag 10 seperated by a dark lane void of stars. Loads of stars and a very pretty sight indeed.

While in cygnus I went hunting for a planetary nebula with the name PK 77+14.1. I really tried to find this but once again had no luck. I've come to the conclusion a filter is a must for these type of objects.

Ophiuchus was getting a little higher now so thought I would hunt a few unseen by me Messier objects. Firstly M12 a globular cluster that lies at a distance of 18,000 light-years from Earth and has a diameter of about 75 light-years. Visually it was a fairly remarkable sight. Its has a surface brightness of Mag 12. I was viewing this at 28 degrees in altitude so viewing conditions were not ideal but the cluster appeared as a nice bright and very tight circular smudge in the 21mm hyperion. In the 8mm hyperion a few stars were resolved, but the cluster didn't really open up.

While in the same area I dropped down 3 degees to M10 another dim globular cluster slightly dimmer then M12 but similar size. Once agian in my 21mm no details seen but in the 12.5 ortho I did resolve a few stars. It is about 70 light-years in diameter and lies about 16,000 light-years from Earth. With a visual magnitude of 6.6 and an apparent diameter of 15 arc minutes.

By now it was fast approaching 01.30 so decided to call it a night.

Added another 3 Messier objects to my list. Now 45 objects seen.

[Beulah]

Awesome, Doc, I really enjoyed reading that. Exellent report, and the seeing was excellent, wasn't it?

I discovered the M13 a few nights ago, and with my 8" Dob, the outer stars were resolved...

You've given me some ideas to hunt for tonight. I'll be well chuffed if I find the Ring nebula.

[calibos]

Can't wait to get my LB16 under the stars like Doc. Would you believe I've had it since before Christmas and have only done one session with it. The rest of the last few months, the scope has either been in one piece but the skies were cloudy, or the skies were clear and the scope was in pieces while I performed mods.

Of course I have missed the Winter skies with it and likely will miss out on Spring Galaxy Season. Those will have to wait till Autumn/Winter/Spring '09/'10, but boy I can't wait to use the scope on some of these Summer objects Doc so elegantly reports on.

M13, I really can't wait for. I think a nice FOV filling Glob is just made for testing aspects of scope performance on, never mind being one of the most beautiful types of DSO's that actually look like the astrophotographs unlike most other types of DSO.

I remember viewing M13 last year in my Orion XT12i dob with my 8mm Hyperion. Globs are a DSO that also need good seeing and good optics as well as decent apeture to resolve them to the core. I remember one particular night where the seeing was great, my boundary layer fan was letting the mirror perform at its best and even at 200x+, M13 was resolved to the very core with absolute pinprick stars filling the FOV. Like diamond dust in the eyepiece. That showed me my collimation was spot on and that I had gotten very lucky with the quality of the optics in my Chinese Orion scope.

Hopefully when I get my LB16 on it, it will show I have decent optics in that scope too. While the XT12i already was able to resolve it to the core, I am hoping that the extra half magnitude grasp of the LB16 will pull another few hundred stars into view while brightening the rest and I'll witness an even more dense sprinkling of diamond dust. While I didn't really need a paracorr with the F4.9 XT12i, I believe it is much more necessary on an F4.5 scope. M13 will really help me nail the correct paracorr settings for minimal coma with so many stars in the FOV to judge the coma reduction on.

Also can't wait to put my new filterslide with 2" UHC/OIII/H-Beta to use. I'll finally be able to use the 21mm Hyperion in 32mm mode with an OIII filter and with the extra apeture of the LB16, I should get some amazing widerfield views of the Veil. I was limited to 21mm with the XT12i because I had no 2" filters at the time. Anyone want to buy some 1.25" filters

Its all ahead of me Doc. Thats why I love reading your LB16 observing reports.

[Ben Ritchie]

Nice, Mick - I really enjoy your observing reports too.

[Talitha]

Excellent session Mick, thanks! On an exceptionally transparent night I was able to study M5 for a while with the 120 achro and was surprised to see exactly what you said, it looked like a mini-M13. There were glowing cascades coming from the side.. like the tendrils which flow out of the big fireworks, know what I mean? Absolutely stunning. Thanks again for your report.

[Doc]

Thanks guys.

And Carol your description of "tendrils which flow out of the big fireworks" is a great description of what I saw.

And Calibos I can't wait till I get my UHC and O111 2" filters and a MPCC. It will be a while yet. LOL

[Doc]

Also can't wait to put my new filterslide with 2" UHC/OIII/H-Beta to use

Calibos could you please explain a little more about your filterslide as this is very similar to what I want to do.

[calibos]

Calibos could you please explain a little more about your filterslide as this is very similar to what I want to do.

Hi Mick,

I ordered a Moonlite filterslide. AFAIK they will fit most focusers. The filterslide fits inside the UTA.

I'll have to rotate my LB16 spider because one axis of the spider is in front of the focuser. ie Drill new spider holes and fill in the old ones. I also ordered a new shorter drawtube for my focuser because my current drawtube is oversized and would hit the filterslide when fully racked in.

Me being me I can't leave well enough alone though and have a few mods planned for the filtersilde. Going to mod it with a toothed track which will interface with a knob with a toothed gear. ie. Knob on the outside of the UTA beside the focuser. Turn the knob and it drives the slide up and down along its travel. I didn't want to be reaching in behind the shroud all the time to slide the filterslide up and down and it wasn't going to be easy from the front either with the permanent full circumferance lightshield I'll be fitting. The geared knob will mean I can change filters from the Eyepiece.

I also ordered the Dew heater upgrade for it. I'd be wiring it permanently to the back of an RCA connector panel on the UTA to which all my other UTA mounted Dew strips and powered devices connect. I didn't want the slack needed in that cable to cover its slide travel length to protrude into the lightpath. I came up with a solution not unlike a scaletrix cars power pick up. ie 2 copper tape strips along the filter slide analgous to the conducting metal lines on the scaletrix track and the RCA panel jack permanently wired to two spring loaded power pickups attached to the filter slide bracket.

ie Filterslide Dew heater wired to the copper tape. Springloaded fixed position contacts always in contact with the tape no matter what position the filterslide is at, No dangling wires! Copper tape will work because it came with the Kendrick secondary dew heater pad. Its for carrying power to the pad across the spider without having thick wires running along the spider. They gave me loads with the secondary heater so I had plenty to spare.

Last and coolest mod is this. 3 small slots cut in bracket. A patch of copper tape on each slide of each slot. 3 bridging contacts attached to filter slide. Positioned along its length such that when say the UHC filter is perfectly centered below the drawtube, the bridging contact on the slide will electrically bridge the copper patches on either side of the slot cut in the bracket. Ditto for other 2 filters. When they are in position, their bridging contact will bridge their specific slot. And whats soldered to the copper tape patches in the slots? Why the positive wire from an LED. An LED for each slot, ie an LED for each filter. And where will the LED's be. Why they will be in a little transparent tictac box . Mounted inside one end of a tictac box that has been partitioned into 3 little compartments, that has one side lined with Red Rubylith filter film, that has been sprayed gloss black on the outside to match the scope, and whereupon I have stenciled out of the paint the words. UHC, OIII and H-Beta.

So what happens? I turn the knob to move the filterslide and I don't have to look inside the UTA to remind myself which filter is engaged or to see whether it is perfectly centered. I'll know which filter is engaged and that it is definately perfectly centered because H-Beta will light up in glowing red letters beside my focuser:D

[Doc]

Wow you have been busy. Very neat idea, I like the idea of the toothed rack and knob sounds very neat and a great idea. The electrical side of it is beyond me I think. But to get a light to come on when each filter is used sounds neat.

Don't the filterslide mounted inside the UTA get in the way of the lightpath?

So if one doesn't go down the route of the electrical idea of knowing when your filter is positioned below the focuser correctly does it just manually click into place?

What sort of power supply are all these items connected to on your UTA?

Maybe soon you will get your scope under your skies to check all this.

[calibos]

We've got about an inch to spare between the edge of the mirror and the inside edge of the UTA. If you look into your mirror tub you can see the 1 inch gap around the mirror. The filterslide gives about half an inch clearance behind the filters, ie Fully racked in your drawtube can protrude half an inch into the UTA. Thats the bulk of the depth of the filterslide, so by my reconing the filter slide is probably about 3/4 of an inch deep and at most 1 inch, so even if it does pretrude into the lightpath it would only be by a hairs breadth. Regardless, I'll come out of this with less protrusion into the lightpath than I did before. Like I said, I originally had a much longer drawtube in my Moonlite focuser. All my EP's came to focus with the drawtube nearly fully racked in. The only reason I got a refractor sized 4inch drawtube was because my barlowed planetary webcam needed masses of out focus. Of course most of the time this meant the drawtube was fully racked in for the EP's and most of that 4 inch length was protruding inside the UTA into the lightpath. Silly me. Should have originally specced a much shorter drawtube and just added a drawtube extension for the few times I would be webcam imaging. The filterslide has precipitated me rectifying this mistake. Didn't then want to then risk a filterslide dew heater cable curling out and flopping into the lightpath and ruining the goodwork. This dewheater cable generally wouldn't be a problem when the slide is fitted to larger permium dobs where they have much more space between the UTA and the lightpath for it to flop around in but on the lightbridge we only have 1 inch free and clear from the lightpath. I knew the filterslide itself wouldn't protrude but wanted to make sure the dew heater cable wouldn't either.

For manual operation the filterslide has a clickstop for each filter slot. Don't get me wrong. The filterslide in no way needs my mods. One can reach in between the trusses or reach around from the front of the UTA and manually slide it up and down. The clickstop lets you know when it is perfectly centered, you would easily memorise which filter was in which slot and slide it up and down with your eyes closed. Me, I am modding it with the rack and pinion knob because other mods to my scope will slightly complicate reaching in behind the shroud and reaching around the top of the UTA and because I once saw a webpage with a big 36in dob with a similar filterslide LED indicator mod and I just couldn't get the idea out of my head

As for power to the UTA: When I was planning to implement some dew control I asked around for recommendations for a dew controller and strips. DewNot was the recommendation for the strips and Dewbuster was the recommendation for the Controller. I was thrilled to discover that the Dewbuster was highly customisable when ordering. ie. not only could it be ordered with a lot more heater outputs than most of the competition but it could be configured with regulated 12v electrical outputs and even lower voltage outputs. My mind started racing with the possibilities.

The Dewbuster could be my Dew Controller, My power distribution block and my Low battery level indicator/protector/shutoff. So I did an inventory of my plans and realised that half my stuff was on the UTA and half on the base. It was much of a muchness whether I mounted the Dewbuster controller on the UTA or the Lightbridge base. Either way, cables were either going to have to run from a UTA mounted Dewbuster back down to the base devices or from a base mounted Dewbuster up to the UTA devices. I decided to permanently mount it on the base to save the extra weight it would have added to the UTA and the concommitant need for more counterweights to balance it.

I then realised that it was a recipe for Spagetti junction with all these cables running up to the various devices and dewheaters on the UTA. ie. A nightmare at setup and break down time.

I came up with a solution. My base mounted heaters and devices would mostly be permanently wired to the base mounted dewbuster. ie. JMI TNT motor system, scope ground and spotlights, 5 fan Fan controller, secret scope theme lighting device (all will be revealed in time ), 2x 2" heater strips for a heated eyepiece rack/box and 1x Orion Intelliscope DSC handset heater pad.

On the UTA I'll have 1x2" strip for the EP, 1x 3"+1x 2" strip for the Stellarvue F80 Raci, 1x .925" strip to heat the Green Laser pointer, 1x 3v output to power the GLP, 1x temp sensor controlled output to power the secondary heater.

So how do I not have to hang all that off the UTA without a mess of dangling cables?

I checked with John Marstiller of DewNot and Ron Keating of Dewbuster and they told my it was perfectly OK cut and shorten cables and to use RCA/Phono connector panels. Thus I have a 6 jack panel attached to the UTA and an identical 6 jack panel mounted to the base. All the UTA devices stay permanently mounted on the UTA, get their cables shortened, jacks removed and soldered directly to the back of the connector plate. Ditto with the panel on the base. Wires soldered to back of panel that are permanently connected to the Dewbuster. The filter slide LED's will share a jack with the 3v GLP power jack and the filterslide dewheater will share a jack with the low current draw .925" GLP heater strip. In between I have a cable bundle, ie the 6 cables heatshrink wrapped into one neat bundle with 6 RCA/Phono jacks at each end. Setup and break down other than putting the scope on the base and trusses and UTA on the OTA is to grab this one neat cable bundle and connect up the jacks to the panels on each end. This way I got to have my cake and eat it. ie. have an excessive amount of powered gear permanently mounted on various parts of the scope but be able to set up and connect it all without a spagetti junction in a matter of seconds.

When I unveil the scope its going to come as a shock to may people how much work I put into it. More work and €€€ than many would be prepared to do. I am sure many people will wonder why I didn't apply the K.I.S.S. principle (Keep it simple stupid) My answer would be that I actually did apply that principle but more in terms of the use of the scope not in terms of the work and mods on the scope. ie. A lot of work was involved up front building it but the purpose of most of that extra work is to make set up and break down and use of the scope as quick and easy as possible. We don't have 300 days of clearskies like Arizona here in the British Isles. We have got to take the gaps in the clouds as they come. I want all this extra functionality but want to be observing within 5 minutes with the scope performing at its best from the off (hence my cooling and boundary layer fan mods) Its bad enough setting up a scope in 5 minutes only to see the clouds roll in when you've finished. How frustrating would it be taking 30 minutes to set up only for the clouds to roll in and then it takes you another 30 minutes to break it all down.....and then the skies clear again.

So most of my mods are functional or enable quick and easy setup/breakdown. Some are aesthetic and some are whimsical like the filterslide LED's and the secret Lighting mod, but at their core, they are all about taking spontaneous advantage of the cloud 'Sucker Holes' in the quickest amount of time with the minimal of fuss.

Does that answer your questions!

TBH when I unveil her, I think I will do a youtube video explaining all the mods because a post on the subject would probably run to 20,000 words!! TBH, you are one of the few people who would appreciate and not scoff at such long wordy posts. You are one of the few people I have seen that is capable of posting gargantuan posts like me

[mdstuart]

Fantastic report, it was so clear. I carried on in UMA and LEO hunting galaxies... found some new galaxies NGC 3998 / 3377 / 3412 / 3489 and found 3389 which is faint so very pleased.

Then looked at the globs M3 / M15 / M 92 and M56 just awesome with the 10 inch. Really 3D WOW, as a Chrisitian it makes me just stop and consider it all...

Then M57, as you say a grey doughnut shape, really stands out against the black surround.

Finally lets try that Lyra double double, yes no bother, E Bootes, bright but again no probs and finally that Draco one 2" yes splits well..

So another good night as was yours.

Mark

[Doc]

Calibos it sounds an amazing set up. I sway more towards the KISS end of the scale, not to say I don't like modding my scope as I love it.

Are dew heaters on the filterslide a vital addition to have as I have never had my eyepieces freeze over or even dew up. The secondry has a few times.

And you have answered all my queries very well. Thank you.

Btw where do you llive, are you near Nottingham. As I woulld love to see it.

Well done Mark you have seen some great objects there.

[calibos]

Hi Mick,

No, the dew heater for the filter slide is not strictly necessary. My rationale was just 'better to have it and not need it, than need it and not have it'. Its actually funny now that I think of it. I would be the last man standing on an observing field if heavy dew hit. ie There isn't a single optical surface on my scope that isn't pretected from Dew. Do you know what though. It would all be rendered moot when everyone else packed up in disgust at the Dew and headed home and I was left with the prospect of staying in a field in the middle of nowhere on my own! So I don't think all this anti dew gear will extend Dark Sky sessions . It'll certainly rule out the frustrations of Dew when observing from home though. Half the time, if clouds didn't prematurely end back garden sessions, the dew did instead.

I actually live on the east coast of Ireland south of Dublin Mick. That said, after reading the SGL4 Thread I said to myself that sounded like a great weekend away, great craic and great observing. You never know, you might get to see her at SGL5

[Doc]

What a shame we live so far apart.

Btw how are heating your secondry as I found this really dews up. I just blast it with a hairdryer, the KISS method works well.

[hal2000]

Good report Mick, and it's nice to see someone else doing some observing in Ophiuchus, one of the most ignored of all constellations. You should be able to bump up your Messier score nicely if you stick with it, there are another 5 Messier objects there and about, all globular clusters, although M107 and M9 can be quite difficult. Don't miss 61 Ophiuchi and 70 Ophiuchi, both excellent double/multiple stars. Have a go at Barnard's star as well.

[Doc]

Thanks Hal.

The problem is with Ophiuchus is it's so low down and only really visible on very good nights.

[calibos]

What a shame we live so far apart.

Btw how are heating your secondry as I found this really dews up. I just blast it with a hairdryer, the KISS method works well.

Most guys are using Kendrick 'Wraparound Stalk Heater' on their LB16's Kendrick Astro Instruments - Newtonion Dew Removal, Newtonion Dew Heaters, Newtonion Dew Control

Seems to work great for them but I just worried one is not heating the mirror directly but instead the solid chunk of aluminium stalk. Thats going to absorb a chunk of heat and thus battery before before it even starts conducting that heat to the mirror via insulating silicone adhesive! And the stalk is going to radiate heat thermals into the lightpath.

Instead I went with a Kendrick S3 secondary heater pad. These are generally used for hollow stalk retaining clip secondaries, but it is possible to use them with solid stalks like ours too, as long as you used a good quality silcone adhesive to glue pad to stalk and mirror to pad. I've use a thin layer of adhesive between mirror and pad to maintain good thermal contact and a thicker layer of silicone between the pad and the stalk to insulate the stalk from the pad. In other words, so that battery power isn't wasted heating the stalk and the cold stalk doesn't radiate heat thermals into the ligthpath.

One last thing about the filter slide. I had a brainwave last night. I pulled apart on old CD-Rom drive and found a perfect low profile motor (opens and closes the drawer) with all the gears and pulley's and momentary switch I need to motorise the filterslide. ie. Turn a dial one way and the motor slides the filter slide one way and turn the dial in the other direction and the slide moves in the other direction. I couldn't have bought a more perfect list of parts that came out of that CD rom. I only have a 3v power lead going to the UTA and it turns out 3v was exactly the power the motor needed to deliver the torque and speed I needed to move the filterslide. ie not too fast and not to slow......jest right!

BTW, I have zero electronics experience, I just like taking things apart and trying to figure out like they work. I learn as I go along.

[acey]

Great report Mick and good to see you continuing to get plenty of use out of that big dob - neighbours permitting.

Calibos - a little bit of intrusion into the light path doesn't do much harm - some focussers do this. In fact there's an argument that when you use a low-profile focusser to reduce the intrusion, you pay for it in terms of greater light scattering into the focusser (a longer focussing tube receives less incident light). This filter thingy sounds interesting - it's a chore fitting and removing them otherwise. My only worry would be that if the filter is not actually fitted onto the eyepiece barrel then you might get stray light reflecting off the filter and into the eyepiece. Deep-sky filters are highly reflective (since they transmit such narrow wavebands) and I've found that when I try to use one in a light polluted environment I can have problems with reflections, even when the filter is screwed on. I wonder if the filter wheel/slide is meant for lunar/planetary work where the light issues are different.

Mick - Abell 39 and the Cygnus planetary (=Abell 61) sound ambitious targets under a mag 4 sky, even with a 16". It will be interesting to see how you manage with an OIII. I came across this selection:

My Choice of Abell Planetaries

which gives Abell 39 as an easy-sounding mag 13, but it's big and of low surface brightness. Certainly well within your aperture range (it's reportedly visible with a 13" and OIII from a dark site), but in a different league from the other targets you've been going for. Abell 61 isn't listed so must be even tougher.

There are a couple of great planetaries in Cygnus, though - NGC 6826 (the famous Blinking Planetary) and NGC 7008 (the "Foetus nebula"). I looked at the latter through the 12" last week and it showed a lot of detail - I haven't looked at the Blinker for a long while but it's very bright and will be a breeze for you if you haven't tried it yet. When you look straight at it, it disappears - that's the blinking effect. It would be a Caldwell to add to your growing Messier tally.

Andrew

[calibos]

Hi Andrew,

Its definately made for narrowband filtering as opposed to being specialised towards lunar or planetary.

Would you run into the problems descibed in a straight from the factory lightbridge. Undoubtadly yes. However, my LB16 will be fully flocked, Secondary blackened, 12" permanent full circumferance lightshield extending the top of the UTA and a further 6" removeable lightshield opposite the focuser. Will also be adding a baffle ring around the drawtube opening. ie. Some full moon night I'll blow some smoke into the lightpath to maximise the baffle diametre with the focuser racked fully in. in other words I already have plans in place to minimise or eliminate light scatter.