Mandy D

Dave? I would say that Dave is the most uncat like name I have ever heard, but I know someone with a cat called Mandy Button Biscuit! Cool scope, though and awesome kitty.

But, I bet they don't have a pair of KT66s!

Ah, right! I know the ones. I use them on my camera lenses, too and have imaged the Sun with one.

If the filter thread size is 58 mm, then a 60 mm filter is unlikely to fit. It has to go over the body of the lens, which will be significantly larger than the filter thread dimension. Measure it with a ruler or calipers and then add at least 6mm for clearance. Make sure the filter is secured properly before pointing it at the Sun, even if imaging only. You don't want to destroy your sensor.

The Moon, imaged last night at about 23:47. Nikon D800, 600mm, f/8, 1/160s, ISO-100. 50% stack.

Lovely job on that scope. Must be great to have it back in service. Nice images of the Moon, too. You gotta love the Hammerite finish on the rings and original mount. That certainly dates it.

I thought Skylink was "the other guy" not Richard Branson. But, totally agree that we do not need the number of satellites he is throwing up there for internet connections.

The Moon, last night at 23:45 in surprisingly clear skies. Everything is back to normal this morning, though, with plenty of clouds for everyone to share! Nikon D800 600mm, f/8 1/250s, ISO-100

If the hexagon key is hardened, one wonders why it broke. The best guess is that the tool is made from Chinese monkey metal of some sort, not good quality steel, so will probably drill OK. If it is hardened, then spark eroder is the way to go, if you have one to hand!

Probably obvious, but with a left hand helix drill, don't forget to run the drill in reverse! 🙃 Also (to the OP) buy some good quality hexagon (Allen) keys, to go with the new grub screw.

Sorry for the late reply, I've not been in the office for a few days and needed to see which one I am using. Your link is to the wrong product, here is the one I have: https://www.startech.com/en-gb/hdd/s352bu313r

Very nice! Lovely natural looking colours.

Clear skies at 03:30, so I set up and captured the waning gibbous Moon at 94% full. Image is a 25% stack from 336. Nikon D800, 600mm, f/8, ISO-100, 1/250s. Processing in GIMP.

Scroll up a few posts and you will see a free one from the OU that I mentioned. Lots of people have run multiple imaging sessions.

I love my two Newts. I have a 200P and a 250PX and I find both easy enough to use. Obviously mine are not astrographs and would have the problems associated with that if you wanted to add a full imaging train to the focuser. With a Newt everything seems to come down to two things: quality of finish of primary mirror and collimation. The focuser can always be upgraded if that were an issue, of course. The central obstruction does cause a small loss of contrast as all the frac enthusiasts keep reminding us, but I find it is easily recovered in processing. I don't think you will end up pulling your hair out trying to get a good image out of your proposed scope, but you might catch a dose of collimation fever! To be honest, I don't generally bother checking my collimation and still get acceptable results, so unless you are a total perfectionist, it should be good. I do like my RC6, though. If the scope is not up to expectations, upgrade the focuser, get the primary mirror refigured to 1/10 wave or better if that is your desire, maybe replace the secondary with a better one and you really have not lost a lot. In all events, it will work well for planetary imaging when Barlowed. Personally, I prefer focal extenders, but whatever suits. With the right mount, they work well.

M4.5 is too big, yet 3/16" is too small? 3/16" = 4.7625 mm! Try 2BA = 4.70 mm Also look at the pitch of the thread. 3/16" comes in UNC and UNF. Chances are that in aluminium, it will be a coarse thread (UNC?) and a 3/16" UNF will not just have the wrong pitch, but be too large on the root diameter.

Yes, when I was first looking at telescopes the vendor was shutting down their showroom and offering decent clearance discounts on ex-showroom stock and I was in France at the time. I considered the 150P as it was cheap as chips, but then noticed the 200P was not much more, so convinced myself to move up to that, but the 250PX was not lot more again, so moved up again. The next step was the 300PX solid tube Dob (no longer produced, sadly) was a big increase in price and although I was seriously tempted, I could not convince myself it was worth the extra cash. Besides, the focal length also increased with this one and made the full Moon too large for my crop-sensor camera. So, I ordered the 250PX and we had it delivered to my partner's parents, not thinking much about the size of the boxes it would come in! When we finally arrived back in the UK, the boxes were still in their hallway as they were too big to easily move. 🤣 It is now residing in France and, at some point, will have to come back to the UK!

Then there is the 200P for just another £80 on top of that. Seriously, though, you are looking at some good scopes, there. Do you want a Dobsonian mounted scope or is a tripod essential? Once you get to the 150P, these things are getting pretty big, but you can generally store them on their mount with the tube vertical and they don't take up a huge amount of space, but can be fun to pick up as a single assembled unit. You need to consider whether you want to lug a larger scope outside on a regular basis. My 200P has not seen the sky in months due to a bad back.

The Moon. Captured last night at 21:25 just as the clouds were approaching, which gave me two minutes after setting up to, frame, focus and grab 140 images. In my rush, I don't think I quite nailed the focus. Nikon D800, 600mm, f/8, ISO-100, 1/250s. Processing in Autostakkert & GIMP.

Very beautiful. It looks almost Victorian, but with a modern twist.

Ahh, so not a simple laser, then! Essentially, you have two sources of laser light; one at 1064 nm and the other, which you want, at 532 nm. Thank you for the clarification. I was unaware that commercially available lasers operated in that mode.

Surely a visible light laser, which produces monochromatic, coherent light by definition would not require an IR filter? My HeNe laser is specified as having a wavelength of 632.816 nm.

Avast tells me that the site your link points to is infected with JS:Agent-EHS trojan.

No problem, you are forgiven! I think it is something that this website does with small images.

If we simply stuck to scientific notation, instead of having an obsession with naming things, it would certainly help with understanding. Scientific (or even engineering) notation removes the need for excessive thinking and reduces the possibility of making a mistake in calculations. 30,000 mAh springs to mind as part of the latest craze for unnecessarily large numbers; why not simply state the correct, obvious and intuitive 30 Ah? Yes, I know it is a sales ploy! I've always thought that popular science authors should start their books with a preface that introduces scientific notation to the uninformed reader and then proceed with using correct scientific notation throughout the remainder of the text. We can dream! <RANT_MODE=OFF> 🤣