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Albireo380

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Posts posted by Albireo380

  1. I bought a Solarmax II 60 recently from Telescope House. I am enjoying using it, but found that the clamshell it came with didn't have screw holes that fit any dovetail I had. Consequently I ended up having to use a binocular mount threaded single screw to attach it to my Skytee. This simply wasn't good enough to mount on my HEQ5 Pro as it kept slipping, and a lot of scope was in danger of hitting the deck.

    I 'phoned Telescope House and asked what tube rings / dovetail they recommended. The chap I spoke to said he thought it was daft that Meade didn't supply a dovetail, so Telescope House had manufactured one + screws to fit the clamshell. He asked my address and said that one would be posted to me, free of charge. It arrived today.

    It is basically a cut down Skywatcher dovetail, with appropriately placed screw holes drilled + two screws that fit this and the clamshell. My Solarscope is now much more securely mounted than before.

    Thanks for a great service Telescope House.

    Tom

  2. I phoned Bern at Modern Astronomy yesterday at 11.30am. I bought an EOS CLS clip filter for my Canon 500D. It arrived this morning (23hrs from order to delivery in Glasgow). I don't think this could be beat. Thanks Bern.

    I ordered a Bresser Giro AltAz mount on Tuesday afternoon from Telescope House. It arrived this morning. And I got the 10% discount : ) Pretty good.

    I can recommend these vendors.

    I have also had good service from Steve at FLO - he has even talked me out of buying a 'scope, as he thought I would not be happy with it.

    Tom

  3. I used to own a 300p Flextube. I have a Vauxhall Zafira and the OTA sat across the back seat, with the dob base sitting uproght in the back. It was a great 'scope and I had lots of good observing sessions with it.

    I changed to a 350p Flextube GOTO a few months back. This is much bigger and heavier. The OTA sits across the back seat of the car but the dob base has to go in the rear on its front. The dob base is VERY heavy and is the limit of what I can carry. It appears as good as the 300p optically, and the extra aperture does seem to make a difference.

    I have not had the same GOTO or tracking problems Rossco72 has had. Once set up I find it tracks stars for 30-60 mins fairly well. The GOTO is reasonably accurate. I can slew 120 degrees between Messiers and get the object on the EP FOV (using a 13mm Nagler, giving me a tFOV of 0.67 degrees). It isn't perfect, but is reasonable enough.

    Size and weight are the issues with the 350p - it is on the limit of what a single person can move around.

    But whichever one you end up with, they are both good 'scopes.

    Tom

  4. A few weeks ago I bought one of the clearance 80mm Meade 5000 Triplet APOs from Steve at FLO.

    I have had some problems with it and at this stage am unsure whether it is misaligned or if there is "sag" in the focusser with a camera attached. I will check this out next time the clouds go. I am no expert imager, so it has taken me several weeks to get this far.

    I spoke with Steve today and he has assured me that FLO will take the 'scope back if I am unhappy with it after trying out a few more tests.

    I am reassured that Steve will do this, as it means that if I have bought a "lemon", I can use the money to replace it with another 'scope (either a Meade or another make).

    So, thanks to Steve for the reasonable way he is dealing with my concerns.

    Tom

  5. Well, just had half an hour out in the back garden with the LX90 and its EZ Focusser upgrade. It seems to work well. I spent about 20mins on Jupiter and focussing seemed very smooth and precise in comparison with what it was before. I wasn't bothered with image shift at all (x125 mag) and I spent some time racking the focus in and out, just to check. Everything seemed smooth and as crisp as one can get from a low-down boiling Jupiter. Pretty salmon pink Nth & Sth Equatorial belts, Southern Polar region and just a hint of other cloud belts.

    Then on to Albireo - easily split at this magnification, and again focus seemed very precise. Okay, not that "snap to" you get on a refractor with a Crayford - but pretty good for an SCT, and MUCH better than before.

    It still isnt really dark this far North (at any time of the night), so serious observing will have to wait about another 3 weeks - but at least I am ready for it now.

    If you have an LX90 or LX200 - get this upgrade, it is cheap and easy to fit.

    Tom

  6. Hope it works for you, but how does this modification stop the mirror moving in the slide when the focus direction is changed.?

    Ron.

    Not sure Ron. I suspect the "thrust bearings" grip better than the Meade plastic washers, so you get finer control and tend not to "overshoot when trying to focus.

    That's all I can think.

    A friend upgraded his LX90 this way a few months ago and swears it has made image shift / backlash a small fraction of what he had before.

    I will see how it performs and will post an update.

    Tom

  7. Well it's good luck then Tom, You'd think Meade would have improved this by now in the manufacture of the scopes, especially with the prices they expect.

    Jeff.

    Yeah,

    The Peterson Engineering parts probably have a value of under 50p if they were part of the Meade manufacturing process. I can't think of a good reason why Meade penny pinched on this - it can't have saved them more than a few pence profit, and yet means their 'scopes are not as good as they could be.

    Sheer bad management and poor manufacturing standards on Meade's part.

    Tom

  8. The clanger could still happen Jeff. Until I try it out under the stars I don't know if it has improved the image shift or backlash. It could also have changed the focus point on the travel of the focus knob - if the focus knob thread wasnt palce on the same point pf the OTA mirror spindle. I guess that could mean that binoviewer or some such item on the back of the OTA wouldn't reach focus. But hey, time will tell ... I am awfully good at figuring out what problems might arise. Although in this case I suspect the EZ Focus kit is fairly "idiot proof" - even for someone as non-DIY as me.

    Cheers

    Tom

  9. I bought a Peterson Engineering EZ Focus kit for my LX90 in the late Spring, and with a few hours spare this afternoom, the Sun shining and SWMBO out into Town, I had a bit of free time.

    I am completely handless and so was very nervous about "messing" with my trusty LX90, which has served me well for 4 years now. But I was getting more and more irritated with the amount of focus shift, particularly irritating when trying a bit of prime focus Astrophotography. The "EZ Focus" is billed as reducing the "play" in the focus markedly.

    Basically the kit consists of 4 things. An instruction leaflet (4 pages of A4 - with poor quality B&W photos), 2 "thrust bearings" - wee washers with rollers in them, an Allen key and big blob of grease.

    The instructions seemed easy to follow, so heart in mouth I turned the focusser anticlockwise until there was no more travel, unscrewed the 3 screws holding the focus assembly to the OTA and gently eased the focus thread off the spindle in the OTA. The focus assembly was then easily disassembled (in 2 minutes) into 5 components (see image). A focus knob (left), 4 plastic washers covered in thick, black grease, a "top hat" (which fixes the focus assembly to the OTA), a small steel washer and then a brass focusser body with threaded steel shaft.

    The idea was to replace the plastic washers with a greased "thrust bearing" and the wee steel washer with the other greased "thrust bearing". Seemed simple enough - at least the piccies in the instructions matched the disassembed focusser laid out on my bit of kitchen towel.

    Having cleaned of the black "gunk" on the focusser I regreased using the Peterson stuff (which seemed a LOT lighter and less like axle grease), replaced the Meade washers with the Peterson ones and then reassembled the focusser. All okay so far.

    The fun bit was then trying to rethread the focusser shaft onto the LX90 mirror focus spindle, through a 1" keyhole in the back of the OTA. Good light is needed (and perhaps some training in keyhole surgery would help as well). However, after ensuring that the focusser was fully turned on its thread anticlockwise, a few minutes careful work had everything sitting nicely.

    I tightened the focsser screws back up again and all seemed okay.

    I then popped the OTA onto the tripod and pointed to the TV mast on the top of the high rise flats about half a mile away. YES - It did focus, and in the full glare of day, focussing seemed easy and with no backlash - of course, I need to check under the stars to have a proper test of this.

    At least the focus mechanism still work (so I an't broken anything). :D

    Roll on a clear night and I will do a focus test under the stars.

    Tom (off to get a beer)

  10. I have the OTA of my first 'scope sitting in the cupboard in my Flat. I bought it "shop soiled" from Dixons in 1975 (I think for the princely sum of £37). It is a 60mm refractor, that sat on a wobbly alt-az mount. I mated a WWII 4 pounder gun-sight to it as a finder. It was an awful 'scope - but I had 2 years of regular observing through it. I first saw the rings of Saturn, moons of Jupiter and M42 through it - it hooked me for life with astronomy.

    I keep it only because when I look at it, I get a warm nostalgic glow, but I haven't looked through it for over 20 years.

    Tom

  11. Thanks John,

    The Tele Vue article makes it all clear.

    If: tFOV = (EP field stop / telescope FL) x 57.3 degrees

    My 'scope would work as follows (with a 32mm series 4000 - 29mm field stop) : (29 / 2000) x 57.3 degrees = t FOV of 0.83 degrees

    Now, working back to aFOV aFOV = tFOV x Magnification in 'scope : In the above example 0.83 degrees x 62.5 mag = aFOV 51.875 degrees

    Meade advertise their 32mm series 4000s at 52 degrees aFOV - and so they are 8)

    I can now work out what combination of field stop, mahnification and Focal Lengths are possible in a 1.25" and 2" EP.

    Thanks for your help.

    Tom

  12. Hi Gaz & CC,

    I think CC has the essence of what I am trying to ask. There must be some cut - off point where the lens bends the light so much, you can't get a crisp field of view - so that may limit the FOV you can get from a barrel of 1.25". But I think your p[oint also comes into it as well Gaz. But there must be a simple equation that determines how much you can bend the light, still get a crisp image to the edge of the field - and pack it all into a 1.25" barrel. I think John must know what this is - as he stated definite aFOVs for a 1.25" barrel at each FL. Just wish I knew it too.

    Tom

  13. Thanks Gaz, but that wasn't what I meant. How did he work out the maximum possible aFOV when the barrel width and FL were known? Why can't you get an AfOV of 82 degrees on a 40mm EP (1.25 inch)? There must be some formula that explains the maximum aFOV for an EP of a given FL. I just can't figure out what it is.

    Tom

  14. John,

    I understand what you are saying re aFOV and FL - do you have any maths behind it? - how did you work out the aFOV when you know the FL?

    Incidentally, there is a 13mm type 6 Nagler with 82 degree aFOV - it is a beaut - one of my favourite EPs.

    Tom

  15. Thanks Gaz,

    Went to Excelsis and there it was - UO Konig, 32mm, 52 degree FOV - priced at $114.99. So I guess the ~£40 sale price was okay. I think the EPO John bid for was the one I was watching. It would be interesting to compare with a Meade series 4000 32mm - same aFOV. If I see another one I will bid and see what they are like - never like to miss a chance to increase my EP collection :laugh:

    Tom

  16. I saw an ad for a 32mm (2") Konig on e-bay last week. I am sure I have seen these advertised in Sky & Telescope, but didn't know anything about them. The advertiser raved on about how good ab EP it was (but then, he was trying to sell it). It ended up going for about £40. I didn't bid, as I didn't know what I was bidding for.

    Anyone tell me any more about these EPs? Are they Ortho's - or what :?:

    Tom

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