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NGC 1502

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Posts posted by NGC 1502

  1.  I think this is a really great idea (or it would be if it hadn’t been cloudy for so long😢).

    The humble 60mm scope can sometimes be looked down upon as a beginner’s scope.  And yet how many of us (me included) have exhausted the possibilities of a scope before “upgrading” to something larger?

    Over the years I’ve suffered from “upgrade-itus” with scopes and eyepieces, then ended up with so much stuff that only collects dust not starlight….

    I’m wishing this idea every success 👍

    Ed.

    • Like 2

  2. Great report, thanks 👍  I too find hand holding my 10x50s not so easy.  Seated observing (as you do) certainly helps. Albireo is split in moments of steady hand holding.  With the unaided eye Alcor/Mizar is an easy double for me. From my light polluted back yard M31 is easy even in my 8x30s.

    Part of the joy of binocular observing is the “correct” orientation views. A local clubmate, now sadly no longer around, used an 80mm spotter scope also used for birdwatching. Mounted on a steady alt-az and with its angled eyepiece, that too was a great way to observe with its “correct” orientation.

    For me my 7x50s are far easier to hand hold than my 10x50s, however the latter give a noticeably more “punchy” view.  The answer to that is perhaps image stabilised binos.  Once at a dark site I used a friend’s 15x50 IS and was blown away by the view and equally blown away when he told me the cost😢

    Keep up the good work and let us know what you see👍

    Ed.

    • Like 1
  3. The 2 scopes you already have complement each other nicely.  ST80 for low power wide field, ETX90 for medium to higher powers.

    If the 130/900 Newtonian was not stable on your current mount your choices are very limited.  Perhaps a short focal length 114/500 Newtonian?  That would give more aperture than you already have, and still provide low power wide field, higher power, and be in budget.

    All the best in your choices😊

    Ed.

     

    • Like 1
  4. On 20/06/2023 at 06:20, Mr Spock said:

    Film has had its day. It's like advocating the use of a horse and cart on a transport forum :biggrin:


    Ouch🙁.  Well ok then, I sort of get that and I certainly admit that digital photography is so much “better” in many ways.

    However, consider this, some folk like classic cars. It’s not because they’re more efficient, easier to drive, easier to get parts for, faster etc.  It’s because some of them are stunningly beautiful, fabulously engineered. It’s the same idea as traditional film photography equipment.  Just holding a Canon F1 35mm film camera complete with an FD lens, there’s simply nothing as satisfyingly fabulously beautiful.  In comparison a DSLR is a lump of uninspiring plastic, even if it’s more “efficient”.

    I’ve had my moan and feel so much better😊unfortunately my shoulder is very sore because a Canon F1 and a bunch of lenses is so flippin’ HEAVY😁

    • Haha 2
  5. Hi Marv. I’ve not done anything like that myself…….but on many occasions Mars has been reported as a Nova😁

    BTW, I’m another fan of Burnham’s Celestial Handbook. My 3 volume set is the rarer hardback versions.

    Ed.


  6. What edition CDSA do you have?   Edition 1 is very different from edition 2.   Edition 1 definitely had mistakes.  Edition 2 was not just an update but a complete rewrite, and much the better for that.

    Just checked my CDSA edition 2, chart 10.  The star you have red circled and is designated Struve 2021 / 49 is just designated Struve 2021 in edition 2.  It’s close to the Serpens Caput border. Perhaps precession has shifted it from Serpens Caput into Hercules. Also on your chart the 49 designation must be a mistake. 49 is a Flamsteed number and is way too high a number for the west side of Hercules.

    Also in my edition 49 Herculis agrees with the other star you have red circled and is designated 49.

    BTW, cannot recall if precession has shifted constellation borders east or west. Anyone remember?

    The above is astronomy when it’s cloudy😊

     

    • Like 1
  7. 12 minutes ago, Franklin said:

    Was out playing with the Vixen 80mm F/11.4 achromat the other night and viewed Epsilon Lyra amongst other things, all four stars clearly split at x121 using a vintage Vixen 7.5mm Silver-top plossl. A "back to basics" session with a manual GP2 and a few old eyepieces, this 3" achromat continues to surprise me. I must get it side by side with the SD81 some time and make some comparisons.


    I would be very interested to hear your comparison 😊

    • Like 2

  8. Do you have an alternative to the conservatory?   Your very hot conservatory is not ideal, neither is the opposite, very cold and damp storage with no air circulation.

    Ideal would be cool, dry, dust free, air circulation and of course secure.

    But it’s often a trade off between the convenience you have near to your observing spot and ideal storage.  If it were me I’d weigh up any alternative storage you may have and make the best trade off (compromise) you can.

    Perhaps in the coldest months of the year when your conservatory doesn’t get extremely hot, it may be the best compromise. And of course the coldest months have the longest hours of darkness.

    Ed.

  9. 7 hours ago, bosun21 said:

    I must admit I do enjoy doing lunar observing whilst wearing a t-shirt in the summer months. Throw in some of my favourite doubles and a few PN. This is sufficient to get me through the lack of astro darkness.


    Only a t-shirt?   Well now, I suppose if it’s dark no one will notice you only have a t-shirt on😁

    • Haha 6
  10. On 06/06/2023 at 07:25, speckofdust said:

    Come to think of it, unlike a refractor, the need to clean the primary mirror at least once in a while and the process of remounting it will also introduce errors in alignment.

     


    Indeed, with most reflectors that’s true.  Not so however with AstroSystems Newtonians.  The whole primary cell with mirror attached to the tube with tiny precision screws.  It was a simple job to remove, clean the mirror and reattach with collimation unaffected.  Tape could be applied around the edge of the mirror and cell so the felt between mirror and cell did not get wet.

    Simple, effective, brilliant 👍 ……..sadly they don’t make them like that now!

    Ed.

    • Like 2
  11. 15 hours ago, speckofdust said:

    I am sure there is a good reason, but why is it not possible to make a reflector that has all the relevant optical elements firmly fixed in place so that collimation is not needed from time to time? Curiosity....thanks in advance.


    AstroSystems of Luton got close to this.  The primary was glued to thin felt, the felt was glued to a plate that was part of the mirror cell.  This did not stress the glass because the felt effectively allowed expansion and contraction of the glass and the cell in different amounts without affecting the other.  Simple and  brilliant idea!  And no mirror clips protruding onto the optical surface.

    The secondary was siliconed to its mount.  Some versions had a full tube diameter support, some had a shorter single vane stalk.  Whilst these used thicker metal than usual, once set up they did not shift.  They were a bit of a faff to adjust but you only needed to do it once!

    I once owned an AstroSystems 8.5” f5 Newtonian on an alt-az pillar mount. It was brilliant. And then I STUPIDLY SOLD IT!!

    If anyone has one, I urge you to be TOTALLY STUPID AND SELL IT TO ME😁

    Ed.

    • Like 1
    • Thanks 1

  12. Over many years I’ve made several Dob mounts and modified others.  I think experimenting is key because it’s hard to predict how well it will work in practice, especially (as mentioned) at high power.

    There’s so many factors involved and not just in the choice of materials.  I once made a Dob mount for a Skywatcher 10” Newtonian tube assembly bought secondhand. It was ok at low power but iffy at over 100x. After lots of frustrating DIY eventually the problem was revealed. The plywood base of the mount was not completely flat.  As it turned on the ground board at times it was ok but at other times it was not, like trying to push something uphill or downhill.

    Let me explain further “pushing uphill” :-  As the mount is rotated you are also trying to lift the rocker box and tube assembly a tiny bit higher from the ground.  At other times the opposite occurs.  Stiction will vary greatly from no stiction to obvious and frustrating stiction.  

    I’m hoping the above makes sense.  Although the construction of a Dob mount looks simple in design don’t allow that to make you casual. Make everything exactly square and flat, rigid as possible.  Make it less of a hassle to take apart if necessary by not using glue in the joints, just screws.

    The “stucco embossed aluminium sheet” certainly looks the part- and as it works so well rejoice👍

    Ed.

    • Like 2

  13. The Skywatcher ED80 cell easily unscrews as a unit.  As mentioned, when reattaching be careful not to cross thread. Removing and reattaching the cell as a unit won’t affect collimation. With the cell removed this gives access to clean the back of the inner lens element.

    If the problem is between the lens elements it’s a very different situation. Perhaps consider contacting a specialist repairer  like the well known Es Reid.  If you’re feeling brave you could DIY.  An adjustable lens spanner to engage the holes on the front retaining ring would be a good idea. Note the orientation between the 2 elements plus the orientation of them with respect to the cell. Note any spacers.  Pencil marks will help. Go carefully and methodically and don’t rush.

    Finally please understand you can easily mess up. If it were me I’d consider using it as is, or if you can’t live with that contact a specialist as previously mentioned.

    Hoping you sort it👍


  14. Welcome to SGL, you’ve come to the right place, lots of folk here ready to help😊

    A good start would be to do as suggested by Louis D in post #2

    The various ETX scopes were all “go to” technology. That is once correctly set up, use the handset to let the built in motors find your desired object. Once found the scope should follow the object to compensate for earth’s rotation. Sometimes it’s not quite that simple, but that’s the intention if everything is correctly set up and working as it should!

    From the pic I can’t see the handset, do you have that?  It’s an oblong shape with lots of buttons. What’s the tripod on the left?  Doesn’t look like the regular ETX metal tripod.

    A good start would be to open the battery compartment. Hopefully the batteries previously used have not leaked. Replace with good quality batteries. Cheap batteries are a bad idea, and keep at least one spare set.

    Please come back with that photo when you can😊

    • Like 1
  15. 2 hours ago, Jasonb said:


    One thing a friend of mine raised, that I hadn't though of. With a Dob, the design gives you a low viewpoint, in terms of the mirror height. The primary is *much* lower that it would be with a Newt on a Mount, so if you're in a garden with a fence/wall around it, a lot of the lower sky will be invisible for you. Has anyone else experienced that? It's not like you can put a 10" Dob up on a table! :)


    Indeed it’s possible to lose the lower areas of sky in the way you describe. However depending on the surrounding houses etc it can work to your advantage. For me if my scope is lower then my fences hides lights from nearby houses.

    Several years back when Jupiter and Saturn were very low in the south then I used to put my Dob on a raised brick built flower bed to access those planets……

    When I had an 8” Dob then on rare occasions I lifted that onto my workmate to access the lower sky. A bit wobbly but a wobbly view was better than no view!

    Necessity is the mother of invention 😊

     

    • Like 2
    • Thanks 1
  16. Agree with above. There’s no reason at all that a Dob mount should be unstable, it will have 3 very short feet, so if the ground is not perfectly level, no problem.  If the ground is too much on the slope, or a bit lumpy just place something solid under one of the feet.  Long thick grass or shrubby ground may be more problematic.

    In fact a Dob mount is potentially more stable because the tube assembly is supported on both sides rather than one.

    Ed.

    • Like 2
    • Thanks 1
  17. On 28/03/2023 at 21:26, Ags said:

    @Mr Spock I am curious how the SLV 2.5 compares to the Nagler Zoom at 3mm?


    I cannot precisely answer that. However I can get very close, because I have a NZ 3-6, and an original series Vixen LV 2.5.

    The LV 2.5 is more comfortable in use because of its 20mm eye relief. But in other regards it compliments the 3-6 excellently. I’m a double star fan, and on nights of decent seeing the 2.5 teases out those very tight doubles that are so satisfying when finally, a split is confirmed👍

    For me, the 2.5 is a specialist tool, the 3-6 more useful more often.

    Off topic- Those of us who remember the LVs introduction in the 90s will recall how amazing they were. The 20mm ER was a game changer, especially in the shorter focal lengths!

    Similarly the 3-6 with 10mm ER is luxurious compared with times past when very high power meant almost attaching your eyeball to the glass!

    Ed.

     

     

    • Like 2
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