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Found 13 results

  1. First Timer on Stargazers. Using a generic Max-Cass telescope, primarily for lunar viewing. I have had good success with a photo mounted DSLR. Recently, just using the eyepieces (including a Barlow), found I cannot get it to focus through either either the primary eye piece or alternate 90 deg. eyepiece. I tend to see more reflection of my own eyeball and floaters. Can't get nearly the image I obtain with the camera attached. What part of the telescope is likely the problem. Since the DSLR still relies on the telescope focusing knob, Where do I start? Could a jolt have caused a focusing failure, mis-alignment? Closest shop for me is Skies Unlimited in Pottstown, PA. Thanks in advance. If post should be elsewhere, please advise.
  2. Hello Everyone, I have 7x 36mm Baader filters in my QHY Filter wheel. I use a simple Orion 80ED with a manual focuser. I have two questions basically. a) How important is refocusing between the LRGB Ha OIII and SII filters? b) If important, then how do I manually calculate the offset distance between them assuming the filters aren't parfocal?
  3. Guys and Girls, Some basic advice around software please. I dont want to choose software that I spend ages learinng and understanding only to find that there is a much more popular/easier/better software program that does the same thing I want but much better. I have learned in the past that this is as time consuming as it is frustrating. There seems to be so many programs out there I'm almost lost! I am after a software program that allows me to focus my Canon 550D DSLR via my laptop when being used in prime focus, including focusing and controlling the shutter and exposure times. I do have a programmable remote intervelometer but suspect using a laptop will provide me with more control. I am also in the market for a software editing program that allows me to process my images. I am getting the feeling i'll need at least two programs, one for stacking and one for "finishing" the images. Registax is one that I hear about regularly but I get the impression it only work with video recordings from webcams (avi. files) or can I import individual images to stack? I understand webcam footage is simply lots of still images but have heard different answers and wonder if you can import images individually rather than video. Alternatively I'd like to know what other options there are for stacking images please. I am also considering taking a trial for Lightroom, as I continue to hear positive reviews. What I don't want is to get a free program and then find i am restricted in my options, hence the reason I'm considering Lightroom. Is this a better program for editing or are there other suggestions. The monthly subscription isn't an issue but again, if there are free comparable options i'm listening! I have an AVX mount (no guidescope) and plan to use my 550D for some prime focus. So I'm after..... 1) Control my DSLR from the laptop INC live focusing 2) Stacking software for images not video 3) Image procesing software Oh and some clear skies!
  4. hi, cant seem to get your standard straight through 9x50 finder into focus ? I assume you unscrew the objective end slowly to get it into focus,but no luck . am I missing a trick or are they a fixed focus ? many thanks.
  5. Hi All, I think this may have been asked before but I am still not getting this right. My nifty fifty canon 50mm prime lens. I cant focus well due to a) it wont auto focus for obvious reasons. b) when I attempt to manually focus the drive wont engage and therefore the focusing ring just goes around and around with no change in focus. I know that you are meant to be able to depress the shutter button halfway to engage the focus ring? but that doesn't seem to work either? Do please educate me . Cheers, Frustrated Andy from NZ
  6. Having some trouble focusing my Dobsonian. I’m seeing objects but there very blurry, I’ve collimated my telescope already, adjusted the focusing knobs (made sure the screw was loose to be able to adjust), have tired with both 25mm and 10mm 1.25 eyepieces during the day and pointing at bright objects that are far way. I’m not sure if it’s just beginners struggle and eventually I’ll get shard images, but any tips would help! Thank you.
  7. Hi , I'm trying my hand at beginner astrophotography got nexstar 8se with nikon d3200 can anyone help me on how to focus camera attachment is t-ring/adapter thanks
  8. Hi very new to guiding and using an OAG on my CPC9.25 SCT and need some help. A few weeks back I managed to capture 10min subs of IC434 without any real issue. I had my CPC9.25 mounted on a wedge, did an EQ North Align, then Polar Align > Align Mount routine. I slewed to a target and set about getting both my guide camera, Lodestar X2 & my DSLR both into focus on my attached Celestron 93648 OAG. My setup as follows: SCT > OAG > DSLR via Baader 2958550 Protective T-Ring The complete OAG thickness calculated from the manual is 66.8mm, comprising (SCT Adapter 25.3mm, OAG Body 29mm & Male M42 Camera Adapter 12.5mm) I can't seem to find info on optical thickness of the Baader T-Ring but can only assume that when attached to my DSLR, gives the norm 55mm to sensor. If this is the case then I am already at 121.8mm. To get focus in the guide cam I had to add a 1.25" nose piece extension and the original end of the guide cam is just visible above the top of the guide cam holder. Now skip forward to last night, I thought I'd try getting wider FOV images of the same target, no problem or so I thought, I have a Celestron f6.3 94175 reducer, I'll just install that directly onto the back of my SCT and attach everything else exactly as above, behind it. Well, getting my DSLR into focus was no big issue, just had to turn the focus knob a bit, the usual when using the FR but my issue was with my guide cam, the stars were huge doughnuts. Through a process of elimination I figured that I had to move the guide cam in nearer to the prism, so I had to remove the nose piece extension and push the camera all the way in to the holder as well as winding the OAG guide cam focuser all the way down. Doing this I managed to get sharper results from the guide cam but these stars were no longer round, they were very oblique circles, pointed at the narrow ends. After lots more fiddling and swearing I came to the conclusion that I could not solve this issue on site so gave up and removed the reducer. Later on I realised that it may be that I needed to adjust the position of the prism i.e. slide it in more to the light beam. As it happens I did not have a suitable allen key with me to try this. My question/s is/are: am I correct in thinking that I was possibly picking up stars right on the edge of the FR in the guide cam, the edge where all the aberration is? just wondering why it was necessary that I had to reduce the distance to light source of the guide cam but the DSLR distance was fine staying put & only needed refocusing? Thanks in advance
  9. Tonight I was trying to look at the moon with my Celestron Omni XLT 150 Newtonian reflector and I got it lined up on the moon and whenever I looked through at it I would see the spider veins and a black dot and I was not able to get it to focus at all is this due to needing more collimation or something else?
  10. Hi.. I bought a PD Video Camera Dec. last year - to use on my SW 200p reflector - I would like some advise on how to achieve focus - from someone who has succeeded on the SW 200p. i.e. what do I need to place in the eyepiece to get the correct back-focus. I've tried loads of combinations to no avail.. even a sipmle pic. diagram - doing me head in. kind regards.
  11. Hi, Slightly embarrassing question I should probably know better..... My collimation is spot on with my F4.7 Dob (use a combination of cheshire and laser to get everything spot on) and I wondering if i'm missing something: For bright stars such as Vega, Altair etc: Despite achieving perfect focus (visually or in conjunction with a Bahtinov mask), bright stars always look slightly squiffy and I'm wondering if the stars magnitude is the critical factor in all this. Fainter stars (Mag 3+) appear as perfect points of light. Whereas brighter stars I can focus them down to almost a perfect point but when approaching 'perfect' focus the star always develops a very small arc (think of the Wembley Stadium Arch...random I know) along one axis, which too me looks off. It only happens on really bright stars. I'm about to delve into AP soon and know a coma corrector is a must with my scope, but even when centred in the eyepiece I'd expect the bright stars to look like bright symmetrical points as per the fainter ones. Any ideas where I'm going wrong here? Is this the limitation of a reflector telescope? Is it simple physics at play? (ie a facet of wave-particle duality?) For background info I've rechecked collimation and focusing when observing, I've carried out numerous defocused star tests and my defocused star 'light rings' are perfectly uniform. Thanks
  12. Hello, I woke up at the ludicrous time of 5am to figure out if Saturn would be visible from my garden. Thankfully it will be nicely placed between 2 trees for about a hour. The next clear morning I will therefore be setting up and having a first go at another planet (I have only seen jupiter so far). I was just wondering if anybody has any tips for focusing on Saturn? I understand it will be a lot smaller than Jupiter through my 200p. Plus for Jupiter, I use its moons to achieve perfect focus whereas I won't be able to do this with Saturn. I've never tried focusing on a star through the camera before and am a little bit skeptical as to how accurate this will be for a planet. Thanks, Dan
  13. I was wondering if there are any tips or tricks when it came to focusing on on planets? I'm able to focus in pretty good, but I'm unable to make them crystal clear. I'll post my best picture of Jupiter for reference, but I'm just curious if there's something I could be doing better or something I'm not doing.
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