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Hi I have an opportunity to acquire for visual imaging, a 2nd hand (manufactured 2000) Russian TAL1 reflector telescope for about £60. Is this a reasonable price,? Being new to astronomy & not currently owning a telescope I've no idea whether TAL is a quality product, so I'd welcome your thoughts.
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Unable to replicate observed detail in photograph
Matt Hayden posted a topic in Imaging - Discussion
Hello! What with all this locking down business and home schooling my ten year old son, I have dusted off my TAL-1 and created a slightly less than ideal setup in his room. The westward facing window has been providing great views of the moon and venus over the past week. Obviously doing this indoors is not great (the floor is pretty solid, as is the TAL stand!) but it does mean we get to use the scope every evening, rather than going through the process of carrying the whole rig outside every day. I have a T-mount converter for my old-ish Pentax k-M DSLR, but have quite disappointing results with the camera, when compared to the observed image using the eye. The eyeball view is nothing less than banging - crystal clear detail with a 25mm eyepiece, strong contrast - it's spectacular. I add the camera with an eyepiece inside a tube, and can't replicate the same result, or anything like it. It's OK, but not good enough. I've cleaned the eyepiece today and collimated the scope. The primary mirror looks fine other than a couple of tiny dust particles, no scratches or weirdness on the coating. The camera is working pretty well as far as I can tell. Apart from a little clumsy-ness with the adjustments, the clarity in the eyepiece suggests it's all working fairly well. Photo attached of best result from last night. My question is: is this a focusing issue or some sort of aberration? Should I expect focusing to be difficult in the camera eyepiece? What's going on?! Does anyone have any other tips I can try to get this working better?- 11 replies
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tal TAL200K crayford upgrade help
haydencoffin posted a topic in Discussions - Scopes / Whole setups
(also posted in a reply thread elsewhere) Hello there! I'm a newbie to this forum so I apologise if my question has been answered already elsewhere. I've been using a TAL200K for about 15 years but getting fed up with the rack and pinion focuser so i treated myself to beautifully made in Germany 2" thread adaptor plate and a generic 10:1 SGT crayford focuser ( these are branded Skywatcher, Lacerta, OVL but I think they are all the same. ) turns out this is much longer than the original TAL and only near terrestrial objects can be bought into focus. Unless there's an easy fix i'm sending the focuser back for a refund, soooo, is there a low profile crayford or other smooth action focuser that will fit the 50.8mm threaded plate which has a similar low profile to the original TAL ? best wishes. -
Repairing a Tal MT3A Mount STEPPER MOTOR Help... Before anyone says "why bother" let me just answer because I'm not ready to pick up a Losmandy at the moment... So I have a Tal 200K which I have enjoyed quite a lot. I have always known that the single motor MT3A mount was less than ideal but it works and if nothing else, an 8" Russian made Kletsov catadioptric scope on a super solid peer mount is a pretty good conversation starter, and some of the views I've seen of Jupiter, especially with a 16mm Nagler - well they were amazing... So a few months ago the mount stopped tracking and slewing at a star party. I could hear that the motor was spinning or making noise, but the mount was definitely not moving under the motor control. I might have just waited and bought something else, but I've had some major expenses plus I'm expecting another due to a large move about to take place so I can't justify spending the money at the moment, BUT I would really like to have a working mount for the Mars opposition in July. So I decided to tear it down and take a good look. I was able to pull the mount casing apart ... and kept going, largely thanks to the PDF AndyH so kindly shared with me that had all the great teardown photos .. despite the native German which apparently translates into comical English with Google Translate ("Loosen the maggot whisk and the grub screws..." is that right??? ) The part that took me some time was realizng after removing the screws holding the case together and removing the setting circles and springs, that it was pretty difficult to unscrew the collar holding the drive shaft in the mount casing. For that I had to use a long screw placed into a hole in the collar as a kind of spoke to get some leverage to unscrew it. Once it started it was easy. Next I was more apprehensive about the drive shaft- The shaft fits through 2 bearings that had not seen freedom in 15 years, so I had to wack the shaft pretty darn hard from one end to break it free. I did this (again thanks to the photo in the pdf) using a block of wood over the end of the sharft - hitting the wood with a small hammer, and then a larger hammer. Like the collar once it was freed up it was easy to slide it through. From there I just took stuff apart until I got into the drive gearbox. The small clock-like gear assembly was not difficult to remove and finally I got a good view of the stepper motor. At first I thought the gear was slipping on the shaft but it winds up being more serious. I removed the gear (loosened the 2 grub screws.. or were the maggot whisks?.. ;-) Of course I kept all the little screws in a secure place and tried to keep them attached to their mating parts when possible. But I think I'll be able to reassemble things.. I don't see any broken gears. My idea is to clean them up and lubricate them with a good quality lithium grease. THE STEPPER MOTOR I hooked up power and the controller and I clearly saw the drive gear is not slipping, but the motor is slipping, - internally. So I need to either repair the motor which no longer has the torque needed to drive the mechanism, or replace it. There's no way I can get the original motor (Tal is out of the astronomy biz and in Russia), and I don't know the specs about the motor to know how to ID it properly with an equivalent. It may be a type NEMA 17 with 6 leads. They aren't that expensive but will it fit? (looks pretty darn similar) Will the gear fit? Does it take the same signals/control voltages? etc. Alternatively Can the motor be repaired? I don't know much about stepper motors so I have non idea.. I know that stepper motors measure steps in degrees, and I imagine there's a spec that specifies the rate of spin, but I' don't know how to find this out for the motor in the MT3S. I have seen a NEMA 17 stepper motor in Amazon and it's less than $20, has 6 leads and has a 1.8 degree step. I might just take a chance and buy the motor and see if I can figure out the wiring.. if it's the same voltage...??... I've attached an image of the printing on the motor and a short video showing it's unfortunate behavior. If anyone has any suggestions how I can move forward I'd really appreciate it. Cheers. Bob TalMT3S-StepperMotor.mp4
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I'm umming and arring over whether to get a solar filter or the solar wedge. I have read a couple of of things about the wedge both saying I would need a filter as well and if I buy the 1.25" I don't think it will fit in the Tal 100rs the 2 " is way out of my price range so any help much appreciated.
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With my normal 20 minutes of observing time available after watching the last episode of 'The Missing' on catch-up (ever seen a grown man cry? Not 'alf!), my scope of choice was the 65mm 'Light Thimble' that is my TAL Alcor, one of the smallest newts around. I wondered what it could do on M42, and the results were pretty impressive given the dire seeing. At x88, all four of the Trapezium stars were visible, although the dimmest was only just there. The seeing was all over the place and getting focus was difficult. The TAL's focuser is quite loose i.e. It moves position easily, so it was tricky to get right. Some nice nebulosity showing through too. I wonder if a fairly wide UHC filter would work if under a dark sky? Given the comparison with say a 60mm binocular, I think it's very impressive. I had no luck at all with Rigel or Polaris due to the seeing. My notes say that I have manage them before with this scope but not tonight. Castor was a lovely pair of bulls eyes when focused right and the seeing steadied. Sigma Orionis showed three of the four stars, I couldn't pick up the faint fourth but perhaps with better seeing it might happen. I'm looking forward to my 2 year old being grown up enough to look at the moon through it.
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So my new telescope arrived Fri, only just had chance to set it up yesterday. On the whole looks pretty good on my CG5, are a couple of niggles the finder dew shield is a little loose and is a scratch on the tube but nothing I can't live with. Interestingly this one has a black focuser tube rather than the chrome one as standard. Now just need to wait for the clouds to clear
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Hi All, So we were down at my parent's at the weekend and I've been working on my ongoing project to refurbish my old telescope so my Dad can use it - a Tal M from 1994 (!). Here's a picture of this vintage 'scope: As you can see everything is fine except for the fact that one of the tube rings has shattered in a fall. I need to replace the second tube ring but have no idea how to go about it. The rings are cast iron, and here is a picture of the broken ring for reference: What I want to do is either: Mend the broken tube ring Replace the broken tube ring Find some other way of attaching the telescope to the mount. It's an 88mm / 3.5'' reflector. Really nice 'scope - we gave it a whirl to check the optics and got it pointed at Saturn and it still shows a lovely clear picture. My Dad was careful to keep the tube somewhere the dust wouldn't get to it. Which of the above options would be the best solution to fixing this fine telescope for my old Dad?! DD