Adam J

Well its about double the sensor area and a little more sensitive with no amp glow. So I would say that its actually a bargain for only twice the price as normally prices are not linear with sensor area for a given performance level. The 071 falls outside of that pricing as its a much older sensor generation. Adam

Define cheap lol. I have used this for 3 years and felt no need to change it. https://www.amazon.co.uk/Orion-Deluxe-Guide-Helical-Focuser/dp/B00B1N7576/ref=sr_1_63?keywords=guide+scope&qid=1575289643&sr=8-63 For less money this will also work just fine. https://www.firstlightoptics.com/guide-cameras/astro-essentials-32mm-f4-mini-guide-scope.html Adam

Yes people are always worrying about flex, I can never comment on it having never experienced it, I suspect that its because I use an appropriately sized guide scope (you really don't need anything smaller bigger than a 50mm guide scope right up to 1000mm focal length) and without guide rings. I really don't like the ST80 as a guider for those reasons and not least because the focuser is terrible and tilts with gravity even with only a guide camera attached.

The shape is not really the main advantage of this its the zero amp glow, yes amp glow on other chips calibrates out but do you really think that it has no effect on Signal to noise in the areas under that amp glow? If you look hard in images you can even see it in the centre of the right edge of the 294 as an area of increased noise, admittedly you do have to go looking for it though and its more apparent in images with lower total integration.

If they make a mono version ill be swapping out my ASI1600mm pro for one.

Nope, a friend has the GT71 though and I have seen many great images from the Star 71

WO GT71 or a Star71.

well yes same as, but I don't think ZWO makes them either, they are made by some third party OEM.

Yes and the reason this one is square is because its designed for use in 360 degree video applications.

I would not even have to think about it, if I had about 900 to spend it would be the ASI183mm pro, failing that and going for a OSC it would 100% be the 533, no amp glow and comes with a duo band filter (or at least I assume it will in the UK? as it will in the US). Apart from that I like the pixel pitch better and as Olly says you need two frames for M31 with any of these sensors. In that case you might consider the 533 more effective as it will provide a nice 2:1 frame ratio in two panels which prints well should you want. Adam

They are most likely the same company that makes filters for ZWO, as to your other comment above, Bàader are not Chinese.

A friend tried that but FLO declined to forward his contact details. I think that either they have an exclusive deal or he is not doing work for private individuals.

I am very happy with it. Gets better WiFi signal from the obsy than my expensive gaming pc with a killer WiFi card in it. So I kinda feel that your generalising there.

looks a little larger and heavier than what i had in mind. Not sure you could attach it to a scope. Also used vs new.

i5 is total overkill for a mount PC unless you are processing on it too. I would rather save the money and get a filter or something.

Actually an amount of processing power is required for remote viewing at high quality settings. Team viewer uses quite a bit, while the astronomy software uses hardly any. I have one of these and think its great. https://www.amazon.co.uk/Windows-ACEPC-Graphics-Computer-Ethernet/dp/B07VFRZFNL/ref=pd_sbs_147_2/261-2127102-2633139?_encoding=UTF8&pd_rd_i=B07VFS33SB&pd_rd_r=323d8e6f-7d7d-41f9-8f32-b248ce388dbe&pd_rd_w=XEGNY&pd_rd_wg=HSn1J&pf_rd_p=f4a31d1d-8f61-48f5-b6f4-a22ba06df575&pf_rd_r=3NE4NBTS19N8RDZVJ39K&refRID=3NE4NBTS19N8RDZVJ39K&th=1

Redesigned electronics and a aluminium casing as opposed to the plastic shell. Generally looks more the business than the older black model. I own one.

You will get a v2 instead most likely.

Its easy to fix just make a star mask expand by a couple of pixels and then do a 0.5 pix Gausian blur to soften the transition.

See my solution from page 109 of this thread. I also added a third thumb screw. At one stage I purchased the compression fitting that FLO sell for it but its trash and introduces tilt.

It works with a APS-C OSC sensor, but with mono cameras and higher resolution / star sampling it does not do as well. A 8300 or ASI1600 sized sensor is about the limit.

But is the camera sealed within a small clear dome limiting the amount of moist air around the cooled sensor?

It is possible to calculate the band shift at different f-ratios. I would have to look at how to calculate it, in essence the peak transmission for the filter will be shifted away from the Ha wavelength at higher angles of incidence (the path length between the filter layers changes at the incident light moves away from the normal). So the light from the edge of the mirror will be attenuated and instead of your average peak transmission being about 80% it will fall off. As more light comes from the edge of the mirror than the centre it means that baader are optimising for that part of the light cone and range of incident angles as opposed to the light from the centre which now becomes attenuated instead of the edge. That makes even more sense when you think about the central obstruction. Worth knowing because a baader high speed filter will have the opposite effect on slower scopes making them less efficient and so its a bad idea to be using them above F4. In effect I suspect that you would benefit from high speed filters, but even so you have so much light gathering area in that 180mm mirror that even if peak filter transmission is only 50% its optically still very fast. Finally I would look into the reflections and other issues on the high speed filters before making a choice as I suspect that the tolerances on the AR coating will be higher. Image quality is about more than just peak transmission. I have no evidence of issues, I would just suggest you do your homework before jumping in. Adam

Seems to be working ok for you with the 7nm filter so I would not worry too much about it.

Depends, but I would go with a black disk for darks or a light polution filter for luminescence. You can always upgrade to 3nm AD filters and then you can use a NII filter along side the Ha. Adam