Adam J

Altair 102 ED F11 would be my choice, although it is longer than the F7 so depends on the size of you boot.

I would try 55mm as from the stars you have it needs more spacing.

The issue you will have is that while you will end up with a larger FOV and faster optics your going to be at 3.3' / pix with a Esprit 80 and that camera or even worse with the WO GT81. I personally think that once things get over 3'/pix stars start to look more than a little blocky with a small sensor when viewd full size. So while it will be faster to reach a given signal to noise ratio with a 80mm F5 its going to lose you image quality in terms of resolved detail. The difference between your current 2.6 and 3.3 is quite significant when you think that 2.6 is marginal anyhow. I would not think of your current combination as a slow system either. The main limitation in my mind is FOV and that you will find many objects wont fit in without multiple panels. My initial reaction is that you should upgrade the camera to a larger sensor first then go to a faster scope later. But if you really want to go with a shorter focal length then I would chose the Esprit over the WO. Adam

Its a quad core celeron with 4GB of ram and a SSD, so sufficient to preview images in APP during capture etc, but I would be doing the processing in my house on the i7, 16GB PC. The obsy is only 3 meters from the back of the house so I think the wifi extender will give me full strength wifi in that area. I am happy to go out and turn things on and off as I need to roll the roof back anyway, its more in terms of what will give me the highest level of reliability. I have also been wondering about keeping the dew straps running 24/7 to protect the optics from damp on my nice new scope. Adam

Just purchased a mini PC and a wifi extender for the observatory to allow me to remote in from any place in the house. I am planning to operate the PC without its own monitor etc. Any things I need to know about / consider? Is it sensible to leave the entire rig powered or just the PC or maybe I should turn it all off each time.. Adam

Focus is fine in this image.

And this is why I went with the Pegasus astro focus cube. The bracket fits a wider range of scopes from what I can tell, it comes with a temperature probe included and it is proven in use.

Literally the only thing wrong here is dithering and and that it needs ten time more integration.

It went down because it automatically bins the pixels below gain 120.

Never use a gain of less than 120 on the ASI294mc pro as it alters how it reads the pixels.

Honestly you don't want APT for autofocusing you want SGP or NINA. They have vastly better approaches. Adam

It needs to be maintained at ambient temperature so you may want to install a fan to ventilate it during the day so that it does not become an oven and when you open it up the scope is as close to ambient as possible.

Yes, WO literally removed the rotator that they used to include with their flattners so that they could make you buy a separate one at a premium. Meanwhile other makes still include a rotator as standard.

I know your camera has a shutter and that flats need to be sufficiently long so as to minimize the effect of the shutter opening and closing.

Yes Dark flats are for use in place of Bias for flat calibration on CMOS cameras not for CCD chips. In that case you only use Bias.

The movements of the focuser are very very fine mate, You would bearly be able to see it move at all in only 25 steps. My focus cube is 0.006 degrees per step so 25 steps would be 0.15 degrees.

Nothing wrong with that, looks like your doing it right to me.

If you dither then yes. If you don't dither it will get worse. Adam

Pixel rejection only works if you dither the subs, so did you dither the subs? Also thats not very much data so I think you need to collect at least 4 times the amount of subs before you can be justified in complaining about noise irrespective of the format. Adam

No question about it I would go with the TS Photoline 115mm F7 out of those options anyhow, its a great scope and better corrected than the ZS103 from what I have seen. Its the same optic as the Altair Astro 115. Adam

yes that is ice on the sensor.

You 100% need to post some test images of the Ultra narrow band filters on a bright ish star. I have not seen any reviews and I am really interested in the SII filter. Adam

Does not look too bad to me, if anything you have a tiny little bit of tilt. I would not worry about it too much though.

Astrodon are a level above Baader and so while the baader filters have an anti-reflection coating on only one side the Astrodons have the coating on both sides. Hence it should not make a difference. However, having said this in their mounted filters the shiny side is facing the scope assuming your filter wheel screws in from the scope side. Adam

I think your correct, I have been using a 50mm guide scope with my 130PDS for years giving me round stars at a longer focal length than the Esprit 100 so I honestly dont see why anyone would use a larger guide scope. The only thing I may have that you do not is a Pegasus Astro focus cube that is about 300g. Offsetting that I wont by using a swapping the losmandy for a vixen dovetail. Adam