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DaveL59

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Posts posted by DaveL59

  1. Not sure if its been covered before as I didn't find any topics on this one via search.

    So while browsing around on the bay I came across these, available as new old stock from the US. A google around found a couple threads on CN and elsewhere and seems to say they aren't at all bad and might be usable on other scopes. So I figured what the heck, buy 2 and maybe improve the usability of the wobbly LT70AZ and perhaps add ease of use to my other scopes at not too much cash.

    This morning the postie called and dropped off a package which contained

    image.png.2c27e604cd54fcf33125466f262aa075.png

     

    Had a quick look at the LT70 and hmmm, almost but not quite. Methinks some minor mods may be needed here:

    image.png.adf3a710310d15677665edf88060940b.png

    As you can see the drive part is off-centre to the scope control but I think I can see why:
    image.png.a631b7e18cd7d990c376034bab76159d.png

    Initial thoughts are to cut the Tasco bracket to match the length of the metal focuser plate and it may then snug in just right. I'll also need to figure a good way to interface to the focus knob or just remove it and fit something that suits better. Ideally non-destructive tho in case I want to return it to OEM for sale down the road but the simplest route may well be to cut matching slots for the motor unit to engage with and I do like "easy" 😉 

    For the TAL100RS I'll need to make a bracket up as that is a much wider plate under the focuser as well as the focus shaft being thicker, so the Tasco bracket won't be a direct fit as-is. Will again need a means to interface as I defo do not want to hack the TAL knobs about

    So what about the SW130 newt? Well, dead easy in fact. First pop the silver trim disc out of the focuser knob. The Tasco bracket is an easy fit under the focuser tube too.

    image.png.93266fb332aef3fe1f44fe2f8f9de47d.png

    Now the U-bracket in the tasco slides neatly into the exposed wheel and secures to the bracket
    image.png.cc280faa85f01c9742999a00e41435ca.png

    The button you can see to the top of the unit is the clutch release so you can manually focus if needed for rapid/large adjustments.

    So there you have it, a low cost motor focuser 🙂 

    So I do plan on making a few mods to these to slow the rotation rate such that you can achieve finer focus adjustments and also to make the lead detachable from the motor unit. Along the lines described in the CN thread here:
    https://www.cloudynights.com/topic/32182-do-you-want-a-good-cheap-focuser-unit/

    According to the thread these run at around 1 rev/7 secs which seems a bit coarse to make small tweaks to focus, tho of course I've yet to try this out in action. I may find they are just fine but reducing the turn rate seems a useful mod so will likely do that on one at least.

     

    • Like 2
  2. this morning the nice man in red knocked at the door and handed me a box freshly arrived from the US. Inside were these

    image.png.f91e7ab1bbca8502bcb762bee2ddd1b8.png

    Hopefully will make the LT70AZ more usable at least removing the huge wobbles when focusing 🙂 Bought 2 as I may pop one onto the TAL100RS and should work on the SW130 too and even the wee NG 76/350. Not sure it'd work with the TAL-1 but that scope is pretty stable anyway.

    • Like 4
  3. last night using the LT70AZ and svbony 7-21 it appeared orange-ish to me, or at least ochre. More so as mag increased. Adding a 2x and even 3x TAL barlow into the path still gave an orange orb but a little more subtle contrast differences across the disc. I was pushing that scope in terms of ability tho and above 200x things got soft, not to mention the problem focusing and following on the poor, wobbly LT mount. 

    I guess if discriminating reds is a problem then it may well appear white and being very bright won't help. I wasn't very dark adapted when I was viewing having not long had a grocery delivery so that may have helped too. Was certainly less like staring into a lightbulb compared with my previous attempt at viewing Mars 🙂 

    • Like 1
  4. next door had a light high up but thankfully never used it in the previous few years. Apparently the bulb never lasted long, as in a few uses, and they tired of getting up a ladder. No way was I going to mention LED. They also have a bulkhead light above their patio door which causes enough light but at least its lower so not as much a nuisance. Thankfully a young couple have bought the place now and they're refurbishing with a lot of help from the parents, they have taken that high light off the wall. Hoping they don't replace it with anything as they've left the conduit and wire there, they know I have scopes so fingers crossed they turn out to be considerate when they finally move in.

    Peeking over the fence just now to see who was bothering my black kitty (another jet black cat almost his double) I see the bulkhead light is gone too, that'll certainly help keep the light levels down in my garden. Reason for checking was little kitty will be off to vetin'ry in the morning to have his injured eye seen to, so was concerned he was going to get himself further injury. All ok tho thankfully 🙂 

  5. Was able to pop out and have a look too after Morrisons had done their drop-off. Only with the LT70AZ as its quick and easy to pop outside to grab a look before the oak tree swallowed it up. Using the SV135 7-21mm a nice orange-ish ball tho barely able to make any detail tho I could see it had some contrast change across the orb, max 100x with this EP. Popped a 2x barlow in and then I could make out a little more but not to the detail you guys saw. Still was nice to look up and get a better view of it tonight and the SV135 acquitted itself pretty well for its first light 🙂 

    • Like 1
  6. and with a clearer sky, not too shabby for a simple webcam. Set to 5fps rate and 1/4 sec shutter, gain 20 and gamma 226 and there we are, stars and Mars.

    image.thumb.png.63f421a17eabc075746e28043d95b6f7.png

    Can make out the lens in the centre and the 2 "doubles" above it are the IR floods but isn't bad at all really even with the Devil's floodlight rising in the east. Now I wonder if there's an easy way to rig a windscreen wiper to clear the remnants of the rain off that dome...? @Gina any thoughts? 😉 

    • Like 2
  7. 6 minutes ago, Telescope40 said:

    Hello. 

    Not wanting to derail the thread. Quick Q. I see the scopes stood to attention. 
    Thought about this with my 2 fracs. Leave them in their cases but stand them vertical. Would this xause any issues. 
    Thinking movement of “fluid” maybe in the objective lens unit. However. Unsure if there is any “fluid” that could move tbh. 🙃🙃 ?? 
    Have a SW 150ED and Stellarvue 102 scopes. 
    John 

    well glass is considered to be a fluid, so I guess over a long enough period of time it could if left undisturbed eventually flow such that the lens changes shape. That'd apply whichever orientation you store it in but in our lifetimes and our grandchildren's even it'd not be noticeable. Grease in the focuser on the other hand might flow if temperatures get high enough but other than that I'd expect they'd be just fine.

  8. 18 minutes ago, JeremyS said:

    Near/in my bed

    an extra 100 points to that man! 😛 

    Mine live in the conservatory, mounted and ready to be stepped outside or can be used thru the open door, tho some juggling required to get the scope I want extracted from the 3-legged spaghetti etc.

    • Haha 2
  9. You can always black the washer edges to prevent any stray reflections but I see no reason why you can't, so long as there's enough play in the secondary holder to allow adjustments. Was thinking to do the same on the little NatGeo in fact but probably using a nylon washer for that. Doesn't much matter after all if the washer gets dimples so long as the secondary holder can rotate smoothly and not snag or shift as the bolts tighten up.

  10. After a long time since looking at this one, I thought I'd have a look at replacing the finder shoe so I can use the TAL finder in a Synta type holder. So pop the drawtube out and pliers in the tube to hold the nut while I undo the screw. The shoe didn't drop away so I teased it up with the screwdriver to be left with this
    image.png.ecac2e58a56617a1f4d964b1e1dc8563.png

    Drat! That's disappointing given the replacement is smaller in footprint. The old show had been glued as well as a single screw/nut to secure it.

    image.png.c8c8bcc84b865dc8400a531a21fb5a29.png

    Looks like I'll either need to get some leatherette and fill that gap, re-cover the entire OTA or leave this in place and mount the Synta-type foot elsewhere on the OTA. Oh well, nice idea but gonna be some faff then. The old finder does work ok so maybe I'll leave this and just see if I can progress the idea of stripping the grey paint and brassing it then. The other idea on the Synta style shoe was to make it easy to swap the DIY Starsense carrier onto this scope when I wanted to so maybe adding it offset to this shoe would work out ok, can then use a RDF or starsense alongside the optical finder as required.

    While I had the focuser out I laid some sticky-back teflon tape around the inner rim of the 2 collars the drawtube runs in. Has taken out the slop and made it slide smoothly with a little drag in the movement without the metal on metal screech which is a good thing, esp on those very quiet late nights 🙂 

    • Like 1
  11. 15 minutes ago, PeterW said:

    Right.... if I *still* have cold hands now I’ve got these then I am quitting this hobby for something I can do in front of a warm fire!!

     

    I’ve bought plenty of gloves over the years and they’ve never worked ideally, so with some cold nights soon we’ll have to see how these cope...... fingers crossed 😉

    Peter

    5A526C22-3ED1-47F6-BD57-E79159D3DCDD.jpeg

    Perhaps a move to remote-controlled mount and EEVA so you can sit indoors and enjoy?

    I've sometimes thought that but cost keeps me from trying the idea out, not to discount the fact too that seeing it with your own eye(s) in the eyepiece has a definite WOW factor that's hard to beat 🙂

  12. Celestron say a max mag of x269 tho we'd usually say 2x aperture on here. I assume it is a bird-jones being F=1000 but the OTA is only 2ft long (it'll have a lens done in the bottom of the focuser drawtube) so you may find it is soft at the edge of field.

    Eyepieces a 30mm will give a wider view yes, and an 8mm should give you a useful magnification. A Barlow I would say 2x would be a useful limit but how well they really work in a BJ configuration I don't know. Probably better to aim for eyepieces in a range and no barlow, say 30, 20, 12, 8 but then budget soon evaporates away. Decent budget eyepieces are likely to cost in the region of 35-50 each. Plossls are good and not too expensive but as you drop down the FL range below say 10mm you start to find less eye relief and smaller occular lens so may not be so easy to use if you wear glasses for example. The Vixen NPL are good (I have the 20 & 10mm) and around £35-45 each

    As I mentioned before, a zoom might suit as that will give a range of mags for a single price although the FoV will be narrower than something like a BST/Vixen single FL eyepiece they are quite usable and save swapping eyepieces while viewing. The hyperflex 7-21mm from others recommendations or the Svbony sv135 7-21mm would cover the useful range for approx the cost of 2 single eyepieces or less, allowing you to zoom in gradually to get the best view for the conditions/target. I yesterday received the SV135 and can say it is well made and sharp, currently costs around USD 49 and takes about a week to arrive, a quick test on the LT70AZ in daytime it showed very well and is smooth in operation so I am happy to recommend it. Their 8-24mm SV171 is very good too but is huge and heavy but would also work if you wanted to go that route.

  13. received an SVbony 7-21mm zoom today along with the diagonal and some other bits and gave it a quick test in daytime with my 70/700.

    image.png.065575e188d111676b8f0433e54e679a.png

    Works very nicely showing good detail on the treetops even in the dull miserable day we've had with only slight focus tweak needed through the zoom range. The 8-24 is very good too but huge and heavy by comparison. Both very solid build quality so I'd happily recommend either if you do want a step up in viewing. The 7-12 will give a range of 33-100x without a barlow, with a 2x barlow you might need to limit how far in you zoom but should work very well. No chance to test tonight as all clouds here at the mo.

  14. That's much better 🙂

    image.png.7bd23f4c1b48d795eb2142950f66cdfe.png

    I see the shed windows are starting to mist up on the outside so perhaps I'll see tonight how the dew heating works. 10.7C according to the temperature controller but of course the LDR controller has already kicked in so the dome will have been heating since the light levels dropped off.

    Pretty hazy and light cloud up there with only a couple bright stars showing so at the moment not looking like a night for observing.
     

    • Like 1
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