Scooot

That’s a fantastic image Harvey, your experience and know how really shows through. Maybe yet another image in one of the magazines?

It nearly fit 😀 I woke up in the early hours and saw Jupiter very close to the Moon so decided to have a go with the baby tak as it was already set up. This is a single 2 millisecond image at zero gain with the ASI2600MCPro. It took me a while to frame it by which time it had moved apart a bit more. Separation is 3deg 36Mins. Anyway its a record for posterity, hope you like it. 😀

Just found my emailed invoice of November 2015, it was $115 plus $8.32 for 2 day priority mail from Starlight Instruments. Quite a price rise.

Wow, no wonder you’re in love with it, it’s fantastic.

Should be OK it’s waning now

That looks very clever Danny, who needs a Nexus

Lovely shots Reggie, I also love the widefield.

I bet he had a wonderful time. Great result,

For RA think of a roundabout.

I’ve found after polar aligning, if I go to the home position, and polar align again it will be out again slightly. So I do this 3 or 4 times, tightening up a bit each time. I then get an alignment that remains fairly stable. I don’t know why this is necessary, maybe because of the time it takes to PA? Anyway this works well for me. Ive also found that after going to a target, if I press the goto again it will platesolve again and tweak the mount to put the target nearer the centre. Again I might do this 2 or 3 times depending on how accurate I want it to be.

That’s a coincidence reading this. I have the DVD and watched it again with my brother yesterday evening who hadn’t seen it.

That’s a fantastic image.

Thanks Mick, we live in hope . My skies aren’t very good here but I’m curious to see how much more of the Jellyfish could be revealed and how much more data I’ll need.

I was hoping to get some more data on this but haven't had a chance yet. However I've reprocessed it using a new pixinsight script which I've used for the first time called Generalised Hyperbolic Stretch, which was kindly supplied by@mike1485 . I think it looks much more natural than my original effort and the stars are much better, it even managed to tame Propus. Hope you like it but any suggestions, good or bad will be gratefully recieved.

Thanks for this Mike, It’s a fantastic tool. I’ve been playing around with it and I’m now getting the hang of it, the basics anyway. It’s brilliant for controlling the stars. I really like it.

Have you considered changing it to a push-to system with digital setting circles. They help you to find anything very quickly but it doesn’t track. https://www.astrodevices.com/Products/NexusII/index.html https://www.astrodevices.com/Products/NexusDSC/ExamplesOfInstallation/index.html

For the Asi2600 Mc pro 100 gain is 0.25e and zero gain is 0.75e roughly. Read noise is approximately 1.5e at 100 gain and 3.6e at zero gain. I can see using a calibrated debayered sub that the mean background level of the blue channel is 388 ADU. (See below) 388ADU x 0.75gain = 291 electrons The square route of 291e is 17.05e which is the background noise. 17.05 / 3.6 (read noise at zero gain) = 4.74 4.74 is the ratio of read noise to background noise which is slightly less than 5 so I could afford to increase my sub exposure a little. To work out by how much. 5 / 4.74 = 1.06 1.06 squared is 1.12. So I can afford to increase my exposure from 3 minutes by 12% to 3 minutes 20 seconds. It does vary by the quality of each night and where in the sky you’re imaging, when I took this sub it was very high up at around midnight so the sky would have been at its best from that perspective. I think I’ve done that right

Calculating the exposure looks worse than it is, you can get the mean values of a sub from the statistics process. I’ll go through my workings later as an example. Replacing the pixels from a short sub was actually a bit more complicated than you might think.

To check your exposure, try @vlaivs suggestion, I’ve found with my light polluted skies 3 minutes at zero gain is pretty good, any longer doesn’t get me a better SNR. I screen shot it so I don’t forget how to do it

I’ve found the colours are one of the best things about the camera and you shouldn’t have to try hard to bring out the colours. EG this is a single uncalibrated 3 minute sub at zero gain I took a couple of nights ago. All I’ve done to it is debayer, copied an STF to histogram transformation and resized it. I haven’t even colour calibrated it. To see it without a colour cast I just unlinked the STF. As you can see there’s plenty of colour in it and I’d guess you have better skies than me in Norfolk. Maybe try doing a quick process on an uncalibrated sub to see what that’s like.

Oh yeah, probably would 😃

I have this support bracket on mine, it holds the EAF straight etc without excess tension on the shaft and coupler. I think there are different sizes for different scopes.

Hope you fix it. You should have a bracket of some sort taking the weight of the EAF so once it’s all attached there’s very little tension on the shaft. Maybe just take off the EAF and re-seat and tighten everything a little so you can rule out slipping?

That’s a cracker 😀

One of the grub screws holding the focuser shaft hasn’t come loose has it? Maybe it’s slipping.