Adam J

It's more normal to go ha and sii for this object for this reason.

Really happy to see that @FLO have taken up this great little product.

What I would say to you is that when it comes to broad band light pollution from LEDs I have found that the quality of the filers rejection (OD) is almost as important as its bandwidth. Hence my AD 5nm filters are better than you would expect them to be in comparison to something like a 6.5nm optolong filter if you compared them on band pass alone. Adam

My setup comes out at 4.2 arc-seconds per pixel so ill be fine as long as the RMS is lower than 2. Above I meant to say 1.53 arc-seconds per pixel but wrote RMS by mistake. The problem with this mount is its periodic error is not guided is >6 arc-seconds and over a reasonably short period. Or so I am told, hence not suitable for use unguided for imaging. Unless you have a very big pixel scale. Adam

I have one of these on order and I would not dream of trying to use it at 1.53 RMS even with auto guiding. I think this mount is for scopes up to about 60mm aperture / 300mm focal length really or you will most likely lose subs. Ill be using mine at 180mm focal length for portable wide field imaging. Adam

Led street lights improved things, but then came the issues when low power and cost lighting allowed every man and his dog to mount high power flood lights everywhere. Not to mention those twodecorative ones that point directly upwards and should be made illegal. So all in all the led situation has made things better and then worse.

You don't say but this means something different depending on if it's the mono or OSC version. The original OSC does operate in a different HDR mode at low gain. What gain are you using?

Mono or OSC? What scope will you be using it with. What targets are you wanting to shoot. What is your light pollution like?

I do both darks and dithering but some of the more modern CMOS sensors will likely get away without darks . As exposures get shorter and you take more of then you need to dither less often. I normally dither once every 5mins with that being a single narrowband frame or 5-10 lrgb exposures. On the 460ex my friend uses darks but has not dithered and gets good results although recently I think he started dithering.

It's not a visual scope it's an imaging scope this is about what I would expect at F5.

If within the last two years they are likely the new ones. I think it's probably just your lense though now the filters. I think you need to get a telescope if you want good stars.

I really think you need to post an example of each channel, unprocessed equal stretch. The tendency is to stretch oiii data more as it's weaker resulting in larger stars.

I have experienced two, the one on the first scope that I returned for another reason was poorly aligned and so got tighter at one end of its travel in comparison to the other. The one on my replacement scope is very good and I see no reason to replace it at all. I don't think it has any issue with load either. If you had seen it first hand you would know it's a significant bit of kit.

I dont think I can remember having seen anyone post images witht he QHY247C on SGL. I never really understood why it was not more popular as in theory its a great sensor as you show here. Adam

Not coming to a sharp focus is most likely low order spherical aberration from the spherical mirror. Honestly this scope is just not designed for imaging at all. If you want to image and get sharp results you should buy a 130pds that has a parabolic mirror and a focuser optimized for prime focus is making.

It wont be £1500, I would guess at slightly cheaper than an ASI1600mm pro, something in the £1100 range. But I am expecting it to be released in any case, just not till the end of 2021 at the earliest. When it is ill be buying one. Adam

They just put the wrong sticker on it. A few months of dew and it falls off anyway. This would not worry me at all. But then all I care about is the optical equality some others are more focused on aesthetics.

If they had had a dedicated flattener out when I purchased my esprit 100 then I would have a 120 instead. Oh well.

Its likely to just be water or a water mark. Having the camera in a warm house will not work as the moisture is sealed inside the camera. Removing the top of the camera will not invaliate the warrently. Follow my instructions here, use a pure cotton bud to wipe over the sensor cover glass. https://stargazerslounge.com/topic/345559-asi1600mm-pro-desiccant-change/ Adam

Very nice for such a tiny integration of just over 1 min. Really need someone to post a picture of something other than the north America nebula though lol. I have a AZ GTI on order right now.fornuse with this scope. Hopefully arrives at the start of December.

I would go with the 533 in a mobile setup as its a cleaner sensor and you will not have to worry so much about calibration frames. In a mobile setup its also important to gather data as fast as possible so I would select the more sensitive camera, which is the 533...but the ASI1600MM Pro is more sensitive still so I will be sticking with that even for mobile work. I was thinking about using a narrower UV/IR CUT such as the ASTRONOMIK L3 or a baader semi-app to help remove the blue bloat as you suggest, but its really not that bad anyway. There are also other LRGB filter sets with different cut off in the blue and red such as the ANTILA LRGB filters. The Semi apo filter is actually a LP filter too. If you are at a reasonably dark site with the Mono camera lum via a fring killer might be a better option. Or place it in line with your LRGB filters by screwing a 2 inch one onto the front of the scope. But looking at PadrePeace's image above I am not 100% convinced its a nessasary step. Adam

I will be using one at 180mm guided will have to see how it turns out.

and yet the HST has newtons rings. My point was that there are things appart from the cover slip and micro lenses that will cause that and that its possible to get that effect even with as good an optical system as you can make.

My point was only that it may be a combination of factors so not the fault of the filters as such. It's up to you if you want to keep them of course.

My sig is 2 years out of date so you can't work anything off my signature... One thing I would say is that the place I have seen this effect more than any other is in narrow band images taken by the Hubble space telescope and I am sure there are no issues with its camera or filters. It will be a combination of factors acting together as opposed to any single bit of kit being at fault. Hence I suspect op will just have to live with the effect. I'll ll be interested to hear what Chroma say none the less. Adam