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spaceboy

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About spaceboy

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  1. Solar mod ERF suggestions

    I'm only planning on doing it once though Pete so saving the bit extra towards the larger ERF is ok as long as there are gains to be had...... and IT FITS that is?? I think the cells and adapters are my biggest gripe as far as potential cost goes as if my lathe was a tad bit bigger I could have done the majority of it myself, making any necessary changes along the way. Instead now I need to be better prepared and make sure everything is correct before I commit someone else time to it I appreciate a smaller filter will do the job but I also figured the larger 110mm will have everything back out the objective before any possibility of thermals or otherwise gathering and with it so close to the objective I shouldn't have any concerns of the lens getting any warmer than it need to do sitting in the midday sun. It is my understanding the difference in views between an external filter over an internal one is an obvious one and my logic was, if internal was the only choice, the closer I get to the objective the better the views should hopefully be for it?? Unless I am missing something that is ???
  2. Solar mod ERF suggestions

    I think getting the filter in is easy enough. Simply hold the filter with white gloves and get someone to lower the ota over my hand until it reaches the baffle then flip the ota over. I think the best thing to do is try to find some cardboard the right thickness and cut out a 110mm circle and see how it fits the OTA. This will highlight any deviations in the OTA width along with giving me a more practical representation of how things will or won't work. What ever the case I think it is safe to say the general consensus is to go with the Baader D-ERF no matter what size I go with, so that's that box ticked Now it's a case of figuring what size will work and if I can find an afford way to have an adapter made for the lunt to attach to the XLT
  3. I should have known better...

    You can't complain for £20. I once bagged myself a still boxed Helios 90mm evostar with EQ3 off ebay for £20. There are deals out there to be had that's for sure.
  4. Antares 2" 1.6x Barlow

    I had one and can't say I was all that impressed TBH but many sing high praise of them. It is worth noting that the newer ones use up more back focus than the earlier thumb screw ones so something to consider if you don't have much inward focus travel. I believe there were 3 different versions in total with the one with white lettering and thumbscrew to be the best of the bunch.
  5. Down time

    Short summer nights, early morning commitments and the usual poor weather often means plenty of down time for all that expensive astronomy kit so is anyone else guilty of just setting their kit up in the middle of the living room and playing with it pretending there actually is some distant nebula in the eyepiece ??
  6. Solar mod ERF suggestions

    The trouble is a 110mm filter in a 113mm OTA gives me less than a 1mm gap around the circumference of the filter which I have to allow a little for expansion / play. When you add to this the tilt my guess is the filter is going to end up wedged in the OTA at some point. At the money these things are I have to make sure I get it right.
  7. EG Wood London ??

    If I was paying this kid a money I'd want to be able to see little green men on Mars. http://www.ebay.co.uk/itm/VERY-RARE-1894-ANTIQUE-3-1-2-TELESCOPE-E-G-WOOD-OF-LONDON-GENUINE-ANTIQUE-/162704623051 Would I be correct in saying this is more a corner of the room show piece than an actual observing piece? Or is it something Jack Sparrow would have aboard the Pearl ??
  8. I spawned a similar thread a while back John. I have regular eye tests due to glaucoma in the family but the thread actually arose from my concern that a fellow friend and SGL member may have possible eye issues they aren't aware of. It came after they continually questioned the performance of a scope that had already been checked against another and one what many hold in high regards. I think it is all to easy to hold a piece of astronomy equipment as responsible for poor performance and over look the first optic in the train.
  9. Solar mod ERF suggestions

    I like the look of this but the link from the thread to it is dead http://www.thorlabs....tNumber=LMR75/M EDIT: found them https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1433 but sadly none for 90mm filters
  10. Solar mod ERF suggestions

    Some good results there. I don't think I'll even bother with a B1200 if your getting that much on a sensor. In the PST mod I was lucky to get 60% of the disc at 24mm (x41). The lunt mod will be used at higher mags anyway and the sweet spot is created by the etalon so nothing to be gained by the larger BF for me visually. Full disc will still be available to the LS60 in it's native form. Its all gone Pete Tong anyway James. I was so wrapped up in the idea of using a 110mm filter that I didn't stop to think the Baader is 5mm thick. While the filter could be sandwiched between two baffles square on, no sooner you introduce tilt (suggested 3mm) the filter will in fact become wider. With so little room already I doubt the scopes 113mm inside diameter will allow for it. As I want to go with a baader this means either externally mounted 135mm at the same cost of a used Quark or a, 1/2 way down the ota internally mounted 90mm. I think at least the "Solar mod ERF suggestions" question has been answered. Thanks all Now it's a case of either making or purchasing an affordable cell. Any suggestions .............???
  11. Solar mod ERF suggestions

    Sorry mate. I'd mentioned in the thread you were following over on solar chat I had the LS60tha so naturally assumed you'd already knew this. And as for the B1200 ....... This is why I want to avoid an external filter as I hope to at a later date upgrade to a B1200 but want to keep the internally mounted erf as large as possible to keep it close to the objective to send as much energy back out of the ota as possible. The problem is while the Baader has a 90mm erf, once you drop it in a cell your lucky to get 80-85mm clear aperture so it pushes it even further down the ota. I'm assuming you also have to increase tilt further on the erf the closer it gets to the etalon to avoid reflections and ghosting ???
  12. Solar mod ERF suggestions

    Sandwich came to mind earlier today and if I could get the same top baffle as is already in the scope I think I would go with that method. Some sponge type draft proofer to allow tilt on the ERF and flock to offer some sort of protection to the filter from the ota wall and baffles. I need only put the ERF in then slide a second baffle in and job done. Trouble is finding a baffle. We all know if astroboot ain't got it there's no getting it. That said I doubt even if spares were regularly available a baffle may still be a tall ask. 3D printing was the preferred way to go but I would be relying on a fellow member not having a printer myself. Mention solar mod and a lot of people have concerns of people blinding themselves and them not wanting to have that on their conscious. I know it is only plastic but I had thought there would be no real heat involved being so close to the objective and rejecting any energy anyway but I can understand peoples concern as solar does come with its risks. Pete do you think a full aperture external "low quality" filter would outperform the 90mm (80 ish clear) Baader internally mounted half way down the OTA. Also I read that the Daystar are configured for f/30 The omni xlt 120 is f8.33 which is a perfect match to the LS60. Stopping it down would lengthen the focal length not to mention wasting aperture. That would have defeated me letting my PST / TAL mod go if I'm going back to 100mm
  13. Solar mod ERF suggestions

    That's correct James. I wanted the 110mm because it puts the filter as close to the objective as possible but sadly the ota itself is only 113mm internal diameter. My problem here is the Baader's next offering is the 90mm which is going to send it a considerable way down the OTA so as to not clip aperture. I don't want to do this for several reasons. 1) Call me fussy but I don't want to hacking the OTA, and I was only ever going to feed the cell down from the objective end with maybe one small hole in the OTA for a fixing screw to ensure the cell remained in situe. 2) I have been informed that an ERF should be no further than 1/3 the distance from the objective for best results anyway. 3) Again I didn't want to start removing and re-installing more than one baffle if possible 4) Obviously performance is also a factor, and I wanted to get the best results I could for my budget. I have experience with hot summer days and the havoc it can play with internal heat. While the Baader is highly rated by many if an alternative that is equal in performance can be used that is a more ideal size then I would be willing to go with that. The trouble is here many claim to be energy rejection filters but are often are just absorption filters. As above mate. Externally for me mate is another £250, 15mm of which would go to waste And I was hoping joining solarchat would have given me more feedback than it has TBH. Seems great if PST mod advice is needed but Lunt mods are thin on the ground even on a dedicated solar site. My hope was the OTA will expand at a similar rate to the filter not that the filter should get too warm anyway if it's doing its job correctly but a good point all the same mate. Although again the 110mm filter seems a poor choice. Ideally something around 100mm seems the way to go. Unfortunately the lunt filter you linked to on solarchat is only 3.5mm (possible absorption filter) thick which if I have researched correctly, could possibly with heat / expansion create optical errors.
  14. Vixen GP mount and tripod

    I'm sure Stu will be along shortly but in the mean time....... My guess is it is either a DD1 or DD3 controller The Vixen GP is the original and best "EQ5" As far as I am aware it can be upgraded with a Synscan upgrade https://www.firstlightoptics.com/skywatcher-mounts/synscan-pro-goto-version-3-upgrade-kit-for-eq5.html although there is a very slight difference in the mounts dimensions so the additions may be a tight or slightly loose fit. The pic does not show the original tripod which is aluminium. HTH
  15. Dusty Sol

    Made me laugh as everyone who I have spoken to today mentioned "what going on with the sun today it looks really orange?" I remarked that I'm sure the sun is the same colour it always is but something in the cloud may be the reason for our perspective on the unusual colour.
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