Kon

If I get it to collimate properly, would you advise to upgrade the springs at some point? Does FLO have them?

I meant he had it out observing 6 times not the primary 🙂. He told me the collimation is very good but when I checked it was awful. He was using a laser only. It was a genuine sale of somebody who never got into the hobby.

ok mirror will go out tonight/this weekend 😟 and see if that will improve things. Not a spec of dust on it despite being 4 years old (covid hobby and I was told they only took it out 6 times). Thanks Michael...it's a shame as I was at the Peak District last week and I could have brought it with me (but it would have meant that I had to leave the kids behind 🤣). It will be easier to pop up in Oxford and see Ian 🙂.

I feel that something is not quite right. My money is on the primary not been installed properly (I am not sure about your 10" but the 12" mirror needs to be installed by the user and the previous owner did not have any prior experience with telescopes so I think the issue might be lying there?)). I cannot see anything else being wrong. My 8" (although no flextube) is a 5 min job even if I need to touch the secondary.

Thanks Ian, I will probably have to take you on the offer as I am running out of ideas. I will message you later.

Which part is not ok? I think there might be a bit of tilt.

That was my main issue that I couldn't get these equal and in the end I had to remove the spring from the secondary screw.

It did the trick!!. I removed the spring and I managed to get all three clips into view. Very tight space left, not sure why or what the previous owners did. I wonder if the primary is not installed properly or pushed a bit higher? I know for the 300p you need to install the mirror. I might try remove it and reinstall? Anyhow I am happy now. Star test confirmed excellent collimation although there is room for improvement. Thanks again to everyone who gave excellent suggestions.

Thanks, I think it was your post. I am having the same issue. One thing I noticed is that the primary screws have pushed it up a bit. The previous owner had only used 6 times so I am not sure what they were doing as collimation is completely off. I will give it another try later tonight as I don't fancy messing up with components unless absolutely necessary.

Ok I had another go tonight. I had to bring the secondary away from the primary but I am not there yet. It is better but I can't quite see the third clip, it's creeping there. The problem I have is that I ran out of screwing. There is still a few mm gap left between the holder and secondary but it will not go further. I saw another post with similar issues and they suggested to cut the spring a bit. Is it advisable? The primary of course can't be moved unless I adjust the collimation screws to be a bit less tight, of that makes sense. Any thoughts?

I am outside Swindon, Brinkworth, quite rural. I am at the edge of the village with only 2 neighbours and plenty of farms in between. Thanks for the very kind offer. I bought myself a short Cheshire and I had some issues that I posted on getting starting with equipment section this morning. I think I know my problem but I might get you on the offer if I still struggle.

Have a look for Tom Williams at Astrobin. He is doing some amazing planetary work with it. He has told me that it is a big scope and the base doesn't fit through standard doors so you will have to break the base every time you bring it out unless you have other storage arrangements.

For my 12" (f5) i should have the offset (fast). The 8" (f6) also has the offset but if I get my 12" done properly it might be a bit more offset. I think I was doing a more coarse adjustment of the central screw which did not help. I will repeat it a bit more methodically.

You are better off judging sky quality by the milky way appearance from your location. Do you see it and how bright is it?, Does it have some or fine structure? Can you see some of the fuzzies naked eye? I am blessed with dark skies (milky way is bright, with intricate structure and several objects can be seen by naked eye) and it is usually an indication of sky quality for the night; bad seeing the milky way is just there and hunting DSOs is not easy.

Click on 'View Atlas in OpenStreetMap' and you can search using a postcode.

Thanks Michael. I will look into the focuser position too as I changed it to the dual one. From your comments it seems to be a secondary and possibly focuser misalignment. I will have a play again this week and report back.

Thanks for the guide, very useful. The telescope came with a laser so i will give it a try. How do you know with the laser the secondary is out of position (ie what will the signs be)? I get it about the cheshire not being able to see the three clips.

Do you mean the up/down move towards the primary? Yes, I had to play with the central screw a bit, maybe not perfect as you say, although I am not noticing much difference even if I screw it up all the way up. In all cases, same issue as above. So I should be able to see all clips in the end through the Cheshire?

I recently acquired a 300P flextube Dob. I tried to collimate it but I am in a bit of a pickle. I am following astrobaby's guide and it has been dead easy to do my 8". I use a Cheshire with side tube. The issue I am having is how things should look on an f5 Vs f6 . Using the same guide, I can't get the Cheshire cross hair to align with the primary donut if I want the clips to show (I am using a short version of the Cheshire). If I opt for the cross hair to align then I do not see one of the clips. I confirmed the Cheshire is fine as my long one was aligning with the donut ok after I finished with the short. If I have all three clips showing, the mirror has severe tilt when I remove the Cheshire. The spidervanes are all equal. The weather is not helping to do a star test but any thoughts where I may be thinking it wrong? I am using a low profile focuser but that shouldn't be a problem (I moved it from my 8" to the 12"). The tube is fully extended as well (second click). So which one do I trust until tested? Three pics describing the above situation. Ignore measurements as the phone was not properly aligned.

According to my Japanese wife the label translates as Go To light research facility. Same link as above post.

The above images are all with my 8". The 12" is a new purchase and has only been out twice due to the lovely weather we are having. Have a look at the planetary imaging competition where I have posted some of my captures with the 8". https://stargazerslounge.com/topic/415170-sgl-2023-challenge-10-planets-and-special-events/ Or look at the planetary imaging section. In terms of capture, I do exactly the same, record while it's drifting but I use a small ROI of 640x480 but with the planetary camera I end up with 15000-20000 frames to select from . I used to do 3 mins but I have recently moved to 8x90s and combine several captures in winjupos. You can't combine in pipp as the rotation will smear the details. I then sharpen the image in Astrosurface. If funds are tight to get a planetary camera, then a mobile might be a better alternative. @PeterStudzhas posted some excellent Jupiter and Venus images using a mobile and a manual 8". Have a look at the smartphone imaging section. https://stargazerslounge.com/topic/417739-jupiter-with-iphone/ Another one has done the ISS: https://stargazerslounge.com/topic/401962-iss-modules-with-smartphone-and-telescope/#comment-4308010 Finally, worth getting a RACI, it will save your back with the manual tracking.

The centre screw below the locking one. It is a hex screw and you can adjust it until it becomes smooth; if you get it too tight you will find that the eyepiece does not move smoothly; loosen it slightly until you find a good balance; in the past I was able to put a dslr without slipping after adjusting it.

You probably need to tighten the tension screw (not to be confused with the locking screw). It is probably slipping and it is causing you the problem. Do not over tighten it. You want it to be smooth.

Excellent images and processing. The IR has really helped to pull the resolution.

I have got all my cameras second hand either from here, ABS or FB second hand telescope sites. (I bought my 12" GOTO from FB recently). You can get some great bargains. No issues at all. There is a nice 462c on ABS for £175 at the moment. It is an obsolete model as of last year but still a fantastic camera. It depends what you are into in regards to imaging. As Ian said, the 462c is a nice camera due to its high sensitivity in IR. With manual tracking forget the mono camera for RGB work as by the time you do your captures even with derotation it will be a mess. A mono camera is fantastic if you are into UV imaging. I got my 462m just for Venus. The first image is with my DSLR (3 years ago) when I started like you and the second with a 462c in 2023, and one of my best Venus with the 462m last year (false colours with IR and UV filters). Have a look at the planetary imaging forum and see what similar equipment others are using but seeing will also affect quality. In 2023, I got less than 5 decent Jupiter captures due to the jetstream. The Venus below was captured under the best seeing I ever had in UK (no atmospheric disturbance at all). I also do a lot of ISS imaging with my 8" and I am pulling excellent details. As I said earlier, with your 8" you should be able to push it to its limits even been manual; it just takes a lot of patience and experimentation. You will also get a lot of excellent advice if you post in the imaging forum which can help with captures settings and post processing. I keep tweaking things every so often.