Alien 13

The synscan motors are better in a lot of respects but there are one or two advantages with the dual axis ones. The dual axis motors will run off a cheap 5.2V mobile phone battery bank (you need a usb cable, chop off one end and fit the required plug) so making the mount more portable and self contained. Easy to set up, just do a quick PA and you are ready to go for either visual use or short focal length imaging with a DSLR and camera lens. Alan

I think at some point we need to decide if we want to randomly explore the Moon or exploit it, this could involve heavy mining or even just crashing future satellites etc at there end of life into the Moons surface to provide raw materials for any colonization builds. Alan

I do love Maks, they are pretty much bomb proof, lightweight and easy to mount and the views are jaw dropping at times on the right targets that suit its narrow field of view. I use a smaller version for lunar imaging and do like the secure way a heavy DSLR camera can be fixed to the visual back, I also find the Mak makes a decent long f/l telephoto lens for daytime use too. Alan

This is another of my crazy thoughts, if for example you have a light shining at a distance of 10 miles from an observer then switch it off is the time delay before its detected the same as it would be at the speed of light? A more in depth and a bit off topic thought I have had is what would happen if the Sun suddenly vanished, would space-time bounce and would the effect be instantaneous or again at the speed of light? Alan

Absolute darkness fascinates me, I doubt there is any place in the universe where you could not detect something even in a box made of "vanta black" Alan

Thank you so much for your informative answer but it does raise the question of the probabilities of the light slowing when its been travelling through space for 13 billion years or so and the accuracy of far object distance measurements. Alan

Do photons ever reach "light speed" i.e. the max theoretical limit? I ask because the speed of light is defined in a vacuum but as we know a true vacuum is not possible even in deep space, reasons being that there is no absolute zero out there and space is full of rays/particles etc. Alan

About time, its so easy to get to the Moon but they should have dragged the Mir space station into Lunar orbit rather than let it crash and burn as a first way point. Alan

A moderate sized SCT with the latest tech USB 3 high frame rate camera is actually a very good combination for Lunar or Planetary imaging, the camera probably being the most important component.. Alan

Are mono sensors just bare silicon or do they have a special cover glass or window that might be the reason for the additional cost? Alan

Lots of them here...... https://www.amazon.co.uk/Hello-Darkness-Friend-T-Shirt-Black/dp/B01KZPBNMI Alan

I agree with the comment by Olly, it depends somewhat on the sensor pixel size (scale) you have with and without the extension but obviously you will still get the same amount of photons from the "magnified" image as before but if they are a better fit on your sensor then all is fine. Alan

These lenses are always a punt so if they are cheap then worth a go, I spent over £100 to get hold of a radioactive 50mm Takuma lens and it was awful for AP but a gem for use shooting video, it adds some magic to the image somehow.. If you do pick up an M42 lens (look in charity shops too) you will need an adapter, put "EOS to M42 infinity focus adapter" in the search bar. Alan P.S. Look on MPB photographic for used canon lenses, there are often some bargains....

As above, the 40mm STM is very good. I would also consider the standard 18-55mm kit lenses but again the STM versions of this are not so cheap but the normal ones are ok if a bit fiddly to focus. Old M42 lenses are worth a punt especially the 135 and 200mm ones but I have not been impressed with any of the short focal length versions unless they are for daytime video use only and not AP, I think the reason is that the figuring of short focal length lenses and the coatings are so much better these days even at the budget end. Alan

I am not sure but the extra lines of AF pixels exist in all those models, perhaps the smaller tightly packed pixels in the 24mp versions make the problem much worse... Alan