Adam J

I thought Lanthanum was a material used as a coating and or doping to the flint element as opposed to the glass itself. Basically acts as a intergrated minus violet filter. Adam

Yes it's the case for anything with a half decent aperture so 80mm refractors and over. You will want at least a HEQ5PRO. I used a 130pds on mine and I am sure a lesser mount would have been a massive pain in the bottom. The HEQ5PRO is the cheapest mount on the market that will provide consistent sub ascsecond guiding on such scopes. Adam

Get a duel band or tri band Quad band is largely useless in my opinion as Ha and SII both fall entiarly within the red channel. You get nothing more than a tri band would give you.

Yes you need a cut. That is an IR pass filter you ordered. Adam

Ok, I think you need to offer up some maths in support of what your saying as its not making any sense to me at the moment. So long as your not saturating dynamic range should not cause anything to be washed out so long as you have a 16 bit a/d on top of stacking your not going to have any issues with quantization noise. Remember everthing you are viewing online is a 8-bit jpg anyway so 0-255 levels, thats your lot and both camera will be useing all those levels in all situations unless someone clipped their black point. The uk weather might effect you choice of sensor but that has nothing to do with your initial argument. Perhapse offer up some example images to help people understand the point you are trying to make. Adam

2 images would double the number of levels, but who on earth stacks only two frames anyway? By the time you have taken 16 frames your going to be ok. Yes lower read noise lets you take shorter exposures and get to that point faster. But as the KAF8300 has a 16-bit A/D and the ASI1600mm pro a 12-bit A/D it takes more frames for the ASI1600mm pro to overcome quantization noise at lower gains. Adam

That effect is largely mitigated by stacking. When you stack you are averaging values so your final image is not restricted to the same number of "bands" as in the sub frames.

The KAF8300 came outin something like 2008 and is still being sold in astronomy cameras today, 4 years is nothing in this market. Adam

I think that if you want to do narrow band mono is very much the way to go. The only time I might consider a OSC myself is for a mobile setup when I could visit dark sites. Adam

I would be shocked if a KAF8300 based camera did not outperform the QHY268 in narrowband so long as you can do the 30min subs that it requires.

Not sure about that but its easy to get good tracking on a very saturated star as you cant detect its moving. Looking at that occilation it remindes me of a positive feedback in the way it increases. I would say no way it is the fan as you would feel it virbating really obviously if it was causing 12 arcsecind errors. Or maybe the guide commands are out of phase with the reading somehow.

So this is how I have things currently. Just switched out the 240mm vixen bar (now on the top) with a 11 inch losmandy (on the bottom). I was having issues with centering before and after a flip and I think it was lack of rigidity in the scope mounting / rings as the weight shifted. I went for the 11 inch losmand from Ian King alongwith my new 5nm Astrodon 1.25mm, I went with the 11 inch as opposed to the 7 inch as I wanted to move the centre of gravity back a bit to give me a touch more roof clearance, it was clearing it but I had to open the roof to get the dust cap on and off. I could really use some custom length USB leads. Comments and suggestions welcome. Adam

1. Yes from what I have seen that will work ok, but a HEQ5 pro would work better. It will depend on the pixel size though and the image scale. I see improvements down to 50% of my image scale. So for my esprit 100 and ASI1600mm pro, I like to keep guiding at less than 0.7 RMS or I know I am losing detail. I also know that my seeing is often the limiting factor in this respect and not the tracking on me AZ EQ6 pro. If you can keep your exposure to 30s or less then you have a chance with the EQM35 but for long exposures I would get a HEQ5 pro unless you have a camera with huge pixels that is. 2, Yes with an adaptor avaliable from FLO unter the Staradventurer section. 3. Yes you certainly will not be able to go any higher in terms of weight or focal length with that mount.

I would not worry I did it for years with a DSLR and not a single complaint. I would doubt that the sound would get through double glazing.

I do agree I own one myself and its great, just makes for things like Gama Cas and Horses head having ugly stars. Narrower filters with good out of band blocking help reduce the effect as the attenuate the star brightness. I have found that my 5nm Ha Astrodon is much better than the 7nm I had before. More so than you would expect from just the difference is bandwidth so I am assuming the 7nm was leaking some out of band too. Also the effect seems dependent on F-ratio. As you get faster it seems to reduce. I guess the next size down would be the IMX253 in or IMX304 in the Moravian, ATIK and StarlightXpress offerings, its actually quite a bit bigger then the 460ex sized CCD sensor, but still quite a bit smaller than the panasonic chip. Adam

Yes sensor size matters. Just be sure that you can live with the microlensing on the ASI1600mm pro.

So here are another 4 cooled mono sensors in astronomy cameras that have been added to the list i posted previously . IMX 273 IMX 252 IMX 250 IMX 249 IMX 428 A couple of those are of a size suited to DSO imaging the IMX 428 being part of the ATIK ACIS range and sold by FLO. Not seen any images from one yet mind you. Adam

I think you can HW bin them Also by the time you use the ASI1600mm pro at unity gain its only got 4012 bits of depth anyway and I find that very acceptable. Low depth is a side effect of the global shutter. But the Moravian C2-12000a uses the IMX253 that has only 9000e with bigger pixels (worse in terms of time to saturation) and it produces some cracking images from what I have seen so far. Its very new, but looks like the 540/542 are its replacement lol. In effect it will probably have more dynamic range than the IMX183 in use. An important measure is well depth / pixel area. In those terms its not doing bad at all. Adam

They already do , but only bother when they think they can sell sufficient numbers to make a batch as they cant change the whole production line over for only 1000 chips. As a interesting fact there was not IMX183 mono until ASI / QHY persuaded sony to do a run. Adam

Of that list the following are already currently avaliable for purchase in cooled astronomy cameras: IMX 455 - 43.3mm - (likely to be the best anature astronomy sensor ever released) IMX183 - 15.9mm IMX 304 - 17.5mm IMX 253 - 17.6mm IMX 178 IMX 174 IMX 290 IMX 273 IMX 252 - 8.9mm IMX 250 - 11.1mm IMX 249 IMX 428 - 17.6mm You will likely see an IMX 542 based mono and OSC astronomy camera in the near future and IMX540 too. 8 of the sensors on Sonys list where added in the last 12 months so its likely that they are for pre order only. So I would say that evidence is that Sony at least are still investing in Mono sensors. The IMX183 mono was listed as avaliable for 12 months before we saw a Astronomy camera with it in. More new mono cameras will come within the next 12-24 months, I would bet on it. The thing is thats just sony! If you start thinking about other makes there are more. If you look at the 1 inch + sensors on that list then we have in effect had on average more than 1 new mono sensor type of useful size for DSO imaging per year for the last 4 years. I just dont follow how this can be considered a reduction when the last generation of CCD camera sensors where with us for between 8-12 years. Its only this year that ATIK have anounced that the 383L+ is going to be discontinued ad the sony CCD chips are still being sold with no end currently anounced. CMOS change over has if anything at all increased the rate of introduction of new Mono astronomy cameras significantly. Adam

https://www.sony-semicon.co.jp/e/products/IS/industry/product.html Thats a list of sony products for industrial use. Almost all those sensors are avaliable in mono and RGB. Most of them are very very new too. Adam

Probably very very expensive and the pixels are very small. Not sure about those areas, I am thinking about things like self driving cars and security cameras, drone sense and avoid. etc. There are a number of emerging technologies that will require and already require mono sensors. I also work in a very relevant area involving electro optics but am not going to post that kind of personal detail in this forum. Adam

I believed the question was in the underlying context of avaliability of mono sensors to replace the "end of life" ASI1600mm pro. Also the title is "is everything heading OSC" I am simply saying that there is not going to be an lack of mono sensor avaliability because there are applications (many many applications) that simply cant be performed at all with OSC sensors and many of those are high volume applications leading to cheap sensors. So mono sensors will always be avaliable to put in astronomy cameras at not too overly inflated rates. This disparity is inevitable for a couple of reasons and more so with the move to CMOS (ill cover that later). Its inevitable because almost all mono sensors have an OSC version, but not all OSC sensors have a mono counterpart. A big factor being that if you want a APS-C then it will be OSC becuase very few want a mono DSLR but crutially its not because no one wants a mono APS-c sensor in the astronomy comunity. This fact is also advantagious as it means that the camera manufacturers are able to easily make mono cameras with almost zero effort as if they have already made a camera with the OSC version of the same chip, its a firmware change to make a mono copy. Looking at that the other way around then its almost zero effort to make a OSC version of a camera if you made a mono, probably why some questionable OSC sensor choices have appeared in the context of there already being higher performing sensors in other cameras by the same maker. The performance gap between mono and OSC will not be closing any time soon, more so the performance head room avaliable to OSC is not sufficient to enable it to be closed, we are already at read noise figures aproaching 1e- and QE values of over 80%, almost photon counters, yet as you say if you took a old KAF8300 it will still run rings around the latest ASI2600mc pro from what I have seen so far perticually in heavy LP and its what 12 years old? If they stopped making mono chips today it will be around a decade before OSC is able to compete in anything aproaching real terms with the current crop of new CMOS mono sensors. So thats avaliability of sensors covered. Now in terms of the market I would easily believe it is i was told there are now more OSC sales, its cheaper for beginners and many people find mono imaging too much of a pain and want to stick with OSC and I understand why sometimes. However, as I say there will not be a lack of new mono sensors and people who want performance over ease of use will still want a mono camera. I recently commented that I am shocked that people are willing to pay £1700 for a set of Astrodon 3nm filters and butsome astro imagers are willing to pay those sorts of figures for high performance equiptment and while that is the case someone is going to make a mono camera for them. So I think the first part quoated above to be correct, but I would atribute that to a larger number of sensors being viable with moving to consumer level CMOS sensors and improvements in that technology than had been based on CCD technology in the past. But I dont think that means less mono will be avaliable, just more OSC by comparison. In the past: Only CCD sensors are viable for high end astro imaging, CMOS are too high noise and too low QE to compete in OSC or Mono. But due to cost and lack of use in consumer terrestrial cameras very few CCD sensors are avaliable. So they are made for scientific reasons and lack veriety. In addition the tech refresh cycle is slower with bigger perfomance jumps between generations. Now: High investment in CMOS technology has resulted in it overtaking CCD even in consumer products and CCD production is to be halted. But as all sensors will be CMOS you suddenly have a huge choice in OSC sensors and so more OSC cameras are made but this is the bit where i disagree with Ian and ill word it with care. I think Ian is a great bloke, I just recently made a purchase from him and have received excerlent customer service from him in the past, he certainly knows his stuff, but I reserve the right to politely disagree with anyone and will make a reasoned argument as to why I think differently. So here is the bottom line, I simply dont think that there will be less and less Mono cameras avaliable I just think that there will be more OSC avaliable by comparision which is not the same thing. I strongly believe that the turnover rate of Mono sensors will remain at historical levels, hence lower than that of OSC as dictated by the relative demand for them and that Astronomy cameras will be avaliable with mono sensors at historical levels and variety for the forseable future irrespective of the increased veriety of OSC cameras. But even then if you think about it there have been more astronomy viable mono sensors introduced in the last 4 years then in the 4 years prior, so its all a matter of perspective. After all the KAF8600 came out in about 2008 and it was not till the ASI1600mm pro was released in 2016 that it had a competitor in its size class, thats 8 years and so its hardly the case that we had huge turn over of mono sensors in the past either thinking about it. Adam

With all respect to Ian King he is wrong. There are still many application for which OSC makes no sence for comercial use cases. What about near IR imaging, what about UV imaging? What about extream low light levels? Sorry but mono is not going any place yet. If you actually look at the number of mono sensors that have come onto the market recently its actually higher than in the previous 10 years. Adam

Lol well at least your ok about it. I have seen so many people on Cloudy nights posting threads about sending their refractor back because of a few specs of dust that you would not believe! I sometimes think i should have gotten one of these instead of my Esprit 100. Adam