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Albireo380

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Everything posted by Albireo380

  1. Great dogs, Golden Retrievers. I just magnified up the 'photo WH sent in of his 'scope - is that a Spaniel in the left background? Is it WH? Are dogs the keen Astronomer's "must have" accessory for this year? And yes WH, the Hartmann seems to work best at higher magnification - not sure why = may be something to do with image size / definition. Also, it is a pain to put on / take off when observing - you only need to move the 'scope by one mm to lose the object. Tom
  2. Absolutely fantastic image - if I ever manage to produce something as good I will be one happy bunny. Tom
  3. Interesting link CC - if you are going to try it, let us know if it works. I use a 3-hole Hartmann mask to try to sharpen focussing for the DSLR. It seems to work fine on brighter objects (perhaps mag 3 and above). Below that I can't see the object in the viewfinder anyway. But it is fine if I focus using a crescent moon / Jupiter/Saturn as "focus object" and then slew to the dimmer object I want to photograph. Focussing seems to hold okay if I dont slew too far and take too long. Tom
  4. Welcome Allan, lots of knowledge in this Forum. Tom
  5. Damian is right, an 8" SCT is a lovely all rounder (I have one myself). However, despite the compact nature of the tube, they are not that small. I lug mine down two flights of stairs from my apartment to the car, drive 40 miles to a dark sky site and then set up. I am okay with that, but then, I am an obsessive. Some SCTs have problems reaching focus with a focal reducer (not enough forward focus). Down side with an SCT ius that they can give pretty low contrast on planets - due to large central obstruction. Having said that, my 8" SCT knocks spots off my cheapy 6" Newt - it seems that size does matter. Whatever you finally decide on - ENJOY !!! Tom
  6. Glad BC&F have come up with the goods. Pretty fast turn around. What is your 'scope? - just for interest :ky: Tom
  7. Thanks James, I will go digging on e-bay. Tom
  8. The bigger car and house would be nice, but Gaz is right, the 5" Apo is an instrument you would savour for many years. A car loses value as soon as you buy it. Who needs a bigger house? - you can only be in one room at a time. But oh, for a 5" TMB Apo - what joy, what extacy! Just thinking about it makes me drool. Such things dreams are made of. Tom
  9. Thanks for the positive feedback everyone. But as I said, we were just playing around with the kit we had to hand. As I don't have a good "point and shoot" digital camera, I have been trying to replicate (or even improve) on this with my Canon A20 - but to no avail. It just doesn't seem happy mated to an EP using the BC&F attachment thingy (technical term - don't worry if you don't understand it). It has got to the stage that I don't do afocal any more - got so frustrated with out of focus vignetting. So, QUESTION What do you suggest for the bracket that mates the camera to the EP? What is a good (cheap if possible - I am not Scottish for nothing) digital camera for afocal? Am I in fantasy land, or would a camera that takes perhaps 30 seconds of movies be useful - could I then Registax the frames together - or is this cloud cuckoo land? Tom
  10. Here is an old afocal image taken by my friend Malcom and I some months ago. We used his Canon A80, attached to my Meade LX90, with (I think) a 26mm plossl). We were just playing around, trying to see how easy / difficult it would be to do a reasonable image of Mare Imbrium area. We were pleasantly surprised how well it turned out. The attached pic is a merging of 2 shots, giving a slightly wider area covered. Hope you enjoy Tom
  11. Perhaps he sells cars as a day job
  12. 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
  13. Arghhh! My brain hurts - and so to sleep. Tom
  14. Thanks Gaz, I am knackered and can't think straight. I think you are correct, but need a working brain to consider - sleep tight. Tom
  15. Hi Jamie, Glen Douglas is the next Glen north from Glen Fruin. The problem is the proximity of Faslane. Lots of nice nuclear submarines and other high tech military kit. I know a guy who worked there and he said that "anorak" astronomers like you and I really worry them. Are we spying on there latest secret weapon? Almost every time I go to Glen Fruin a police (or military police) landrover cruises past me at 1 mile an hour - giving me a very careful look over. Wish they would turn off their headllights though - ruins the night vision. A couple of weeks ago I got so fed up with this that when it happened a second time in one night, I swore (very loudly) at the passing car and gave a very prominent "V" sign. It was only then I realised it was the local polis - just as well they had a sense of humour. Incidentally, I have heard that Helensborough AS use Glen Fruin as a dark sky site - never seen them there though. Hi Twinkletoes - you just take your courage in your hands and try to ignore the "sounds of the night". Just wear brown trousers and use bicycle clips - just like Martin. Having said that, there is nothing quite like a remote site, with no one (you hope) near you, just the sound of the wind in the trees and the babbling of the nearby brook. Quite poetical - amn't I? Think back to the camping days of your youth - camped out in a one man tent in the Highlands - the nearest road 10 miles away over the hills - only the sounds of nature around you. Once you get over the strangeness of it - it can be wonderful Tom
  16. 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
  17. 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
  18. I probably use a 20mm KK and 16mm Nagler most often - not surprisingly, they match the "sweet spot" criteria for my 'scope. Tom
  19. Yeah - too cold for me. Been out in -7. The Meade was all sparkly and white, really pretty. Couldn't take a 'photo of it as the CF card packed in at -5 and the camera battery ran out after only 30 minutes. Tom
  20. 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
  21. Yeah, You are working away at the eyepiece, minding your own business and suddenly you hear a blood curdling shriek - some poor small furry creature has just been grabbed and ripped to bits a few yards from you. I am glad those nuts who want to release Wolves back into the wild haven''t been allowed to do it yet - otherwise it might be me letting out the shriek - as I get chomped by a pack of Wolves. Tom
  22. 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 Tom
  23. Just back from a couple of hours observing in Glen Fruin (near Loch Lomond) - the observing site is up a single track road, next to a small wood. Reasonably clear night, slight breeze (8mph) and a fair bit of light from nearby Glasgow (20 miles away). Good views of M42 at x100-x180. Trapezium looking crisp and bright, lots of nebular detail. Moved over to Saturn - pretty good tonight, with 5 moons showing at x150 (Titan, Iapetus, Rhea, Enceladus and Dione), also clear Cassini division and 2 southern bands + south polar region. Then had a look at M51, M94, M97 and M106. Was busy burying my face into the 'scope and became aware of some movement off to my side. I looked up and saw two bright yellow eyes looking at me. Now just a minute, I am up a single track road, in a passing place - no houses within a couple of miles - I don't expect an audience - especially with yellow, glowing eyes. I turned on a torch, and there it was, bold as brass - a full grown Fox - sitting calmly ( about 10 feet from me) - just watching me. It wasn't for moving - a bit taken aback, I decided that I was on his patch, so he was entitled to look. I have had bats, owls, rabbits, sheep and cattle, all trying to get close to my 'scope - but a Fox was a new one on me. Handsome looking animal though! Certainly brightened up this evening. Tom
  24. 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
  25. Aren't the Laplacians little pointy eared guys in Star Trek? Interesting site. Tom
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