Adam J

So to be clear this allows you to put a HEQ5 on to a Eq6 tri-pod or is it the other way around?

You can get low vibration fans, look for magnetic bearings. But I would use a water block with flexible 6mm/4mm pipe to a PC water cooling radiator. But to be honest you are limited in how far you can cool them due to the sensor chamber not being sealed (the sensor will frost up). It might cause more issues than it solves. The other thing is that at this time of year with temperatures hovering around zero at night you will not get very much benefit from that sensor being further cooled looking at the dark current chart (it has the same pixel design as the 183 and is likely to have the same dark current) as by the time you are approaching 0c its already got quite a low dark current. At 0c the dark current for the 178 is 0.01e/pix/second. So with a 60 second exposure that is only 0.6e of thermal noise per pixel, that is insignificant to be honest. At -10c you get down to 0.004e/pix/second so you might be able to do longer exposures but it wont give you much more and you will have a hard time doing 5 min exposures with a 130PDS on a EQ5 mount without guide errors. As things are with a temperature of about 0c you could do 120s exposures no problem. Your images are good, they just lack total integration time. If you want to step it up then 30 mins per channel is not going to give you the most impressive results, 6hours is the least I do per channel. Adam

It will be 3 months by the time you get serious reviews. Takes that long to take a couple of images and get a feel for it. Its the same technology as the ASI6200mm pro and that is looking good. Just less pixels.

No a 0.5x reducer will not work, it would leave you at F3 which is way too fast to be pushing a doublet objective to without bad aberrations most notably CA. You would also be very unlikely to achieve a flat non-vignetted field over anything but an extremely small sensor and probably would not have sufficient back focus to allow you to focus the camera with the reducer in place. So you really cant do that. The most you can push your optics to is probably by using the SW 0.85x reducer which will work great with the 533 (from what I have read on here it will struggle to provide a fully flat field across the larger 94 though due to back focus issues). Personally I think that will leave you with a workable FOV and m31 will fit across the diagonal. I can only say what I would do if your heart says get the larger sensor then the 294 is not so bad, I would just rather not have the amp glow myself. Mono is faster in any situation you just have to get a filter wheel and set it to cycle through the filters but I do understand your thinking. Adam

Well forget comparisons to the 1100D unless you want to pay for a much larger sensor. In terms of the other two, I think that the 533 is clearly the better sensor going by the specifications, but you are correct the 294 is larger. If most of your targets will fit into the 533 then go for that if more than a handful will not then go for the 294. So thing like the heart nebula, m31 and the complex around the elephants trunk. I would buy the 533 myself, but that's because there are some things about the 294 I don't like including some issues reported on cloudy nights with uneven calibration when you go deep with it. For you the larger sensor might be right, but there is always a larger sensor so beware of price creep, the next thing you will ask is why not pay that little but more than the 294 still and go mono or maybe get the 071. The choice between the 533 and the 183 is an easier one for me but the choice between the 294 and the 533 is harder. Any reason you are no considering mono? Adam

Bad luck? I have had the same one for 3 years and it was 2 years old when I first got it used. But mine is a mono and I know people have more issues with the OSC version for some unknown reason.

You need to make a custom camera as the ASI533mc pro is not in astronomy tools yet, put 3000 x 3000 pixels and set the pixel size to 3.76um then select your scope and target as normal. Here: So you cant quite fit M31 into the FOV, but you cant really with the 183 either and your giving up a large amount of performance for just that target. Most targets will fit into your FOV and in that instance the 533 is just more sensitive. My FOV is similar in my case with a ASI1600mm pro, so in my case I would do a 2x1 and get M31 in two frames. I have to admit I was not a fan of the 183 even before the 533 was announced though, at least in OSC terms them mono is better. Adam

HSO is the only choice for me, I don't like green in astro-images. Adam

They do get a bad press on drivers because they don't test sufficiently prior to release and they rely on users reporting issues in the early months in order to identify them and then release updates. The process tends to result in stable drivers after a couple of updates but it dosn't do their reputation much good. All in all though its all ok in the end.

Stop and wait! The ASI533mc pro is coming out and unless you really really need the tiny pixels its likely to be much better than the ASI183mc pro and not very much more at all. Its better suited to your 72ED in terms of pixel scale as with the 183mc pro you will be working under the Daws limit. Read this thread: Adam

I think competitions are a different subject to images printed in a magazine.

I would agree and I think this is where the difference lies between imaging from the UK and from a more ideal location, to get to 40-hours on my current image that has so far taken me 14 nights of imaging. You have to take 2 hour windows or even one hour windows of clear sky to make it all add up. In an ideal climate you will get that in half the number of nights and while those 14 nights span two seasons for me I am going to guess they might span a couple of months for some other locations. Every single time you have to battle with all the factors above and just one of them can ruin a night for you. Collecting data from the UK often feels like a battle for me and I have an observatory. I agree with the first statement but it I am sure that they will print the better images larger within the magazine and the more "marginal" images smaller to compensate. I have certainly seen some images online that look much better in the magazine than they do on the monitor. The second part that I quote above I am not able to agree with, data acquisition in the UK is a battle against the elements and light pollution, I am lucky but most will not have gardens sufficiently large to place an obsy in them and they will be surrounded by other houses with security lighting and the rest. I am going to guess that at your location you get 3 to 4 times the number of clear nights per season that we do in the UK and that you get longer windows on those nights. Last year was so bad that I started a heart nebula project in October 2018 and I am still collecting data for it now. If you don't have an obsy then setup time means you cant even take advantage of the more frequent 2 hour windows we tend to get, if you do then a cat walks past next doors security light and you just lost a 20min sub in the middle of a 2 hour window. So much to go wrong every time you setup and take down. It only takes one thing and the night is lost, it takes some grit to start setting up at midnight for a clear window predicted at 1am because that might be all you get this month and then get up for work the next day. So I think that you have a different experience of data acquisition than me if you consider it a mechanical process, but with me having an obsy I am probably closer to your experience than most in the UK. What I will say is that I don't think that it should be UK only and would miss seeing your images, astronomy is an international community after all, but at the same time I do have a personal preference for seeing and reading about images made by people I have more in common with in terms of the overall imaging experience. I will qualify all this with the fact that I have never submitted any of my own work to a magazine or anything else for that matter, recently I don't even post all my images on here as my current goal is to have them printed and hung on my wall for my own enjoyment. I find processing that is optimal for being printed is different to what looks best on a monitor (Probably my rubbish monitor). Maybe Ill submit the heart when its done and see what happens. Adam

And this is another advantage over ASI183 and ASI294. Two dark frames from ZWO's web page. Top is ASI183mc pro and the bottom is the New ASI533mc Pro. No amp glow at all on the 533 and just look at how uniform the dark is. If there was a mono version of this sensor then I would be very tempted to trade in my ASI1600mm pro for one. Its not impossible they might do a mono run in the future just like the 183mono which came out some time after the OSC sensor. Adam

I use a mini pc and connect to it via team-viewer, this seems very expensive for less capability, that includes the fact that my mini pc has an internal 500GB SSD and is significantly cheaper. I run N.I.N.A on it and its excellent.No messing about with little memory cards I just transfare files PC to PC over the WIFI, the final thing is that you can even access it via a ipad and the team viewer app. Mini PC was £150.00 and the 500GB SSD was £50.00... I did consider the original as a solution but to be honest in the end I could not deal with the idea of being tied in to ZWO products. I dont think its worth the proposed price and thats not something I have said about ZWO products before. Adam

Guys your all replying to a thread from 2018 lol.

More over the focuser on the ST80 is likely to result in flexture.

I think its essential that they place a mixed bag of images up, if its all £20k setups in elevated and dry climates then that would be discouraging and or lack relevance to the average UK reader. At the other end if it was all beginners in the Class 8 back garden with a DSLR then we would not get to see so many nice pictures. So I think that I would want to see a selection from both ends of the bag and everything between, I would not want to see it restricted to formal classes because that would lack flexibility, but clearly if its something that the editor has lost sight of then it needs addressing. I think there should be a hard floor to this mind you, I don't want to see everyone's first ever astro image being printed, but above and beyond this I think that people with a good image for the equipment / location should be up with a chance of having their image printed, maybe with a slight bias to the UK audience. I like to see good efforts on behalf of people who exceed their equipment limitations and interesting images / stories attached to their image the few lines of text currently allocated seem insufficient to do much more than list the equipment used, so where is the story? I want to see their image read the text and relate to how they suffered from equipment issues and bad weather, why they like the image and what they were trying to achieved. Buying very expensive equipment is not cheating, but in my view it should very significantly raise the quality bar for their work being published. Adam

It allows them to make that choice now that they have it, but many will have been looking at the ASI183 as an inexpensive starter camera and choosing it based on price while accepting that it most likely over samples on their system. I see lots and lots of people posting ASI183 images and they are frequently binned 2x2. With this sensor you can now have a camera in the same price range but it will have more optimal sampling and hence be a better choice for most people. So in that way it replaces the 183 in one of its key market segments. In the majority of cases people who may have chosen a 183 will now be better off choosing this sensor. Its a good sensor I think its best to leave it at that.

You dont need a guide scope over 50mm aperture / 200mm focal length unless you are guiding a imaging scope of more than 1000mm focal length. Anything bigger is a waist of money and more importantly weight. The Skywatcher EVOGUIDE 50mm is a great permium option, but I have used this for the last 5 years with perfect guiding results: https://www.amazon.co.uk/Orion-Deluxe-Guide-Helical-Focuser/dp/B00B1N7576/ref=sr_1_23?keywords=50mm+guide+scope&qid=1573820385&sr=8-23 So what mount do you have and what imaging scope / camera are you using? Adam

It matters for saturation on targets like m42 core and means you don't need multiple exposure lengths saturation is saturation irrespective of stacking. I did say 12 (ok 11.88) stops above so am confused by that comment. Also I did not mention e/ADU at any point just read noise at a given gain. You are right about the full well being 5k its a log chart so not the easiest to read at a glance.

So its got very low dark current (no need to cool lower than -10c) and still over 10 stops of dynamic range at 30dB gain, which in turn will give you about 1.2e read noise. Though I would most likely run it at gain 200 (20dB) and 1.3e read noise for a incredible 12 stops of dynamic range and ~8k full well. That is very very good. Adam

There was a Altair starwave 102mm ED 2017 edition on astro buy sell recently. Probably closer to your 130pds than a 60-80mm scope. So unless you want shorter focal length specifically it's a better choice and at your budget.

Don't worry too much about dust on a used scope. It's bound to pick some up over the years. Do look for improper cleaning and scratches. Large numbers of fine scratches from cleaning with an abrasive cloth are a bigger problem. Having said that though although scratches lower the price a couple of smaller scratches will not effect performance. Look for pits and damage to the flat of the focus tube as may result from over tightening. It it running smoothly. Apart from that it's just general condition. Generally collimation is solid with these scopes.

It is much better (tolerable) on the pro to be fair, the main problem was with the original version, so much so that they had an exchange program when the pro first came out. The pro still works it just seems that you cant cool to the max and you have to expect to change the desiccant on a more regular basis, I guess its annoying but does not totally kill the camera. It would make me favour the 168 over the 071 though. I say this as someone who owns a ASI1600mm pro, the V1 and V2 of that camera had similar issues they fixed it in the pro and I am very happy with mine. I just think in the case of the larger sensors they never quite fully fixed it. Adam

Its not that simple, I guess that all in all the build quality / finish of ZWO products might be considered better than QHY its just in this instance for their larger sensors the design of the sensor chamber on the QHY seemed more effective than the ZWO equivalent going by comments and reviews. In theory if you believe WO then the Z73 should cover a APS-C sensor without issue so the 2600 / 268 are workable for you. Looking at the pixel size then I would say that for you the 3.76um pixels of the 533 and 2600 are a great match to your focal length and more desirable than the 4.63um pixels of the 294. At 430mm I think you will get a workable field of view from all of these cameras but larger is always better as you will get an object like the heart nebula into a single frame with a APS-C but not with the 294 and certainly not with the 533 or 183. If you want to make wall prints then the APS-C sensor will make your life much easier. Being designed for use in DSLR camera the sensor in the 2600 or 268 is unlikely to have any amp glow. Historically Sony chooses to manage this well for this type of sensor, being of the same technology in a smaller package its also possible that amp glow will be much better controlled in the 533 than the 294. Its a balance. Adam