Adam J

As M33 is much close to M31 than us I am sure they are saying it about M33 not us.

Yes and the number of subs and the need for Dark Flats etc with the ASI1600mm pro is something I find annoying owning one. With the KAF8300 i think that the problems for me are with the mechanical shutter (people have those go wrong) and also 7e read noise and not very high Quantum Efficiency by modern standards. The pixels are a little chunky for shorter refactors too in my opinion. I guess for me it was a choice between the 460EX and the ASI1600mm pro not the ASI1600mm pro and the KAF8300. I went for the ASI1600mm pro but to be honest I still flip flop on that choice now when I am running out of storage and for one large image with 4 panels taking 24 hours to stack it with dynamic distortion correction of APP, not that my PC is slow its a older i7 with 16gb of memory and an 1TB SSD. A friend has a 460EX and gets fantastic results with it, less FOV than me but seems much less work too. I could easily convince myself to swap over. Adam

Actually I think the smart money is still on the HEQ5pro its a known performer.

For visual yes, But not if you want to do deep sky Astro Photography. The mount is the most important thing for that is the mount and that it can support the telescope size you want to use. Any 6 inch Newtonain is going to require a HEQ5pro as a minimum. You can pick them up second hand for around £500 With a smaller scope (70mm refactor) you will likely get away with a EQ5pro or a EQM35pro Smaller still (60mm scope or a lens) then a Star Adventurer is a good bet. But as you want to do some visual and deep sky I would recomend the EQ5 pro at the least. Adam

I did not have it in my head that you are making something up and did not intend to imply otherwise, the main issue is that I am at work and so typing fast so as not to get caute on here lol. I am sure your focuser is very good, but I do know others that have been good with a DSLR but not good with a bigger load. Its not up to moonlight or feather touch or even Baader levels of quality, I hope we can agree that. You can tighen it to make it work but that just results in a horrible time focusing as it starts to stick when you apply small adjustments.

You will want to use darks with the 8300 dithering or not. But as above its not that time consuming.

The thing that you need to remember is that well depth if not important its dynamic range that is important and that has a dependency on read noise. The other thing is that you can quite happily use 10min exposures with the 460EX in narrow band but will need 20 or more likely 30min exposures to get the very best from a 8300 based camera. The ability to do long expsoures with the 8300 is not a benefit its a requirement as unlike less noisy sensors it cant produce equal results with shorter exposures. You can still take fantastic images with the 8300 its just that the people making best use of them are in Warm climates and dont suffer from cloud that might scupper a long exposure you also need to be able to guide for 30mins. I would say that 900 is a top end price for a ATIK 383L used these days..... Adam

True but my point was that its an indicator of the quality of the sensor. Not that it takes time. That is possibly true in your case however, having owned one and observed variable comments from fine to not fine from others my working assumption is that they are not all made equal and the QC is not top grade on this item. However the lens is normally very good.

For a start 4/3 is the aspect ratio of the sensor not the physical size if the sensor diagonal. There is a Atik 460EX mono in the for sale section its less noisy than the KAF8300 and does not even require dark frames to get the most out of it so that might be another option. It will still give a very nice FOV if you pair it with the 65Q. It would give you a FOV of 1.70degrees x 1.36degrees at 2.23 arc seconds per pixel. That is actually very similar to the FOV of the ASI1600 with your current ED80 scope. I would personally say that if you want to hang a cooled camera and filter wheel off the back of a SW ED80 you would be well advised to get a focuser upgrade. The ASI1600mm pro is fine, but you need to be aware that its got a issue with micro lens diffraction pattern effect that bothers some people more than others. Hence worth looking it up before you make a choice. Adam

Ah now that makes sense so its also an after sales service from ES in addition to the original pre-dispatch test.

So if i purchase a Esprit (I am interested in the 80) without a test and its got a problem I assume that you fix it exactly the same irrespective of if I paid for the test or not and in fact the test is just a pre-sale confirmation that its a good one to provide piece of mind and prevent the inconvenience of having to diagnose the issue, send it back and wait for it to be fixed or exchanged. Also what does it say about WO that you automatically include a test with their scopes but not SW......got to tell you that part of my reasoning in going SW Esprit 80 and not WO GT81III. Adam

Honestly just go out and get a cheap second hand windows laptop from e-bay, in the long run you going to make your life much harder trying to use a Mac for astronomy and this is not an easy hobby to start with without consciously hobbling yourself.

Iso3200 is exactly what I would have said too.

I can see that you mean but it looks like seeing differences to me, did you take the images at different times?

Better to ask the guy above, but I assume that you would simply connect one of the USB slots on the ASI Air via a USB A to USB B cable into the input port on the hub then the hub supplies the power to all your different devices as opposed to the ASI Air and it just communicates through it. Like I say I can promise that's your issue but its a definite possibility.

cant say for sure that's the issue you have but I will say that some USB hubs are utter rubbish and some are not.

LOL I just posted a USB hub for sale on here and talked about this exactly. Not all USB hubs are made equal.

honestly i have damaged the thread on an adapter trying to get those thing off they are way too tight.

That would make sense all i know is that I dont see it on that star with my 130PDS at 650mm F5 and so I would not expect to see it on smaller apertures / focal lengths either. But its not really FOV so much as intensity as stars being point sources scale in brightness with aperture irrespective of f-ratio.

Thanks I hope I talk sense the majority of the time at least. Baader use 2mm thick glass on their smaller filters. So you need to add 0.7mm in theory. However, you also have other glass in play (sensor cover glass and optical window), the camera sensor position is always a fraction different between cameras etc. So use the distance recommended by WO for your scope as a starting point as opposed to gospel. From the direction of the distortion you can see its too much spacing as opposed to too little. I would take 0.5mm off and test and then if its still out another 0.5mm etc. A digital caliper is essential if you really want things spot on you cant accurate adjustments without one. Adam

Very nice, i think you need to reduce the spacing on your corrector though only slightly.

I would not say that star is bright enough to cause that issue in narrow band.

The next thing you will want ot do it to chop down that focuser tube to stop it heading into the light path!

Did it happen when changing filter? The motor for the filter wheel will have a larger current draw then the rest of that put together I would think.

There is always residue left and the mist will stick to it. I normally do a few iterations of cleaning, however, if you cant see it under normal lighting / no mist then its not going to cause a flats issue.....the thing being that flats are supposed to remove the effect of something like this, its partly why we use them....