The Admiral

What scope are you using? I've got a compact arrangement so avoid those issues, but I did take the precaution of using riser blocks between scope and dovetail. Isn't it something which would haunt you on other mounts? Given the amount of torque that the mount can muster, any collision would probably cause damage to one thing or another. Unfortunately you can't set limits to the movement. Ian

Indeed that is what soft proofing is. I think what you might be seeing,though, when you change paper is really the result of changes in the paper brightness and colour. This is something that Affinity does take account of apparently. But unless the screen brightness is visually matched to the brightness of the paper under its normal viewing conditions, it cannot be relied on to give a print which isn't too dark or light. Professionals go to significant lengths to achieve this (they need it right every time), but we amateurs have to do the best we can. Just Goggle "my print is too dark" and see. Anyway, the easiest thing will be to run off a print and just check, though it might not be so obvious with astro images rather than 'real world' images. Ian

Interesting, thanks for that. I hadn't realised that access to Epson's paper profiles would not automatically be seen in the Mac. May be it happens with Windows too (?), though I don't recall printing through lightroom itself. As I'm slowly moving over to Mac, this is useful to know. Ian

Was Well, that's a step in right direction 👍. You have to use colour sync in order to complete the colour management workflow chain. You don't want the printer to go off and do its own thing. I have a feeling that the actual brightness of a print won't be visible in the proof, as you are using the same monitor to view it. You just have to run a test print and see. I agree, tif seems the right thing to do as a jpeg is compressed and only 8-bit. I'm guessing that for simplicity use sRGB as your screen shows sRGB colours properly. Having said that, since Affinity is a colour managed application I'd have thought you could use Adobe and the application should take care of colour space conversions before sending to the printer. Just my two pennyworth. Ian

At risk of flogging this one, from what I have subsequently read, the Mac Retina display should be close enough for your initial needs. Earlier versions appear to at least display the whole sRGB gamut, later ones something called P3, which is bigger, yet insufficient to include the Adobe gamut, though includes colours Adobe does not. So, as long as your images are within the sRGB colour space then the colours should be reasonably represented by what you see on the screen. I would have thought that if you printed as per the tutorials, then you should get something pretty reasonable. If it's too dark, lower your screen brightness, or just brighten the image, until it looks OK. Affinity is a not as transparent as it should be, in that the paper profiles are not in a dropdown box that you might expect. Have you managed to find them yet? If you still can't find them, I'm not sure what you can do. Let us know how it goes. In fact I need to become better acquainted with Affinity myself, and could end up printing with it, so this is all grist to my mill 🙂. Ian

Posted in error.

Or perhaps this https://affinity.serif.com/en-us/tutorials/photo/desktop/video/332654440/ Or this https://youtu.be/WknxXMLTRvI Ian

But then most people don't want to produce a print that looks broadly the same 😉. Chances are it'll be too bright for a start. It can be a frustrating process and you can end up with quite a few proof prints before you are happy. You could try Goggling something like "matching screen to print" or "colour management workflow", and seeing if there's any advice which matches what you want to do. I'm not that familiar with Affinity, but are there not any guides about printing to be found there? I'm also sure that somewhere in Affinity there will be a means to control the output colour space. Is there something like "colour management" in the set up menu? Or perhaps even in the file output dialogue? Ian Have a look at https://digital-photography-school.com/color-management-in-affinity-photo/

Not sure about this. It's a standard consumer inkjet printer, and should be able to reproduce images correctly. I would have thought using a pdf would just add to the issues. Best to get the cause sorted in the first place. What's needed is a proper colour managed workflow. Ian

Well yes, if you want the print to look like the one screen, then the screen ought to be calibrated. Even that doesn't guarantee it, because if the screen is too bright then the prints will come out dark. Another thing is what colour space are your created files in, sRGB or Adobe? If you are printing direct from Affinity, though, I would have thought it should able to accommodate, as it's a colour managed application. If not, if the Adobe colour space is printed from a non-colour managed app, then it could look washed out. Good luck. Ian

You don't say how you took the darks (unless I missed it). Was the camera attached to your scope at the time, or did you just try it with a cap on? Did you do it in daylight or at night? Bit of a longshot this, but could it possibly be a tiny light leak from somewhere, particularly as you don't see it on the subs, which will obviously be in the dark? Bit late of course, as it's been returned, but worth thinking about with its replacement. Ian

My understanding (😉) is that when AAP does a PA alignment, it calculates where the centres of the circles are that stars would draw out as the mount rotates as part of its PA routine. The aim then would be to adjust the mount pointing in order to align that common centre, (i.e. the pointing direction of the mount's polar axis), with the NCP. Presumably, AAP knows where the NCP is in relation to the stars it sees during plate solving. If there is cone error, it just means that the circles drawn would be either smaller or larger, but their centres would still be at the same position(s). I'm open to challenge on this presumption if you think otherwise. Yes, that's what I think too. So far as I can see, the necessity to establish cone error is only required if you are using the mount's GOTOs. I understand that this is why you need to do a 3-star alignment so that the mount's software can work out the cone error in order for GOTOs to be accurate. If you are aligning by plate solving, I don't think the cone error matters. Ian

Two things are going through my mind. The first is the need to expose though 2 filters, which is only 1 away from doing 3 filters with a mono camera, with its associated sensor efficiency benefits. So using mono becomes a more realistic option. Secondly, I wonder if the algorithm used to extract the separate channels can, to a first approximation, allow for the overlap using the published spectral response? But now we are adding complexity. Personally, I'm all for producing an attractive image rather than one with scientific accuracy, so if you find that using the the Askar set can come up with the goods, then great! I look forward to seeing what you get. Ian

Presumably because you won't be able to separate the signals at all with mono? I hear what you are saying though, there will be some degree of inability to separate signals on a OSC. Ian

Makes perfect sense. Ian

Interesting. The bandwidth for the Baader is narrower than the L2, more akin to the L3. Whether that is all there is to it I wouldn't like to say. Ian

Hmm, interesting. I use the L2 and I haven't come to that conclusion. Mind you, I've not done a comparison, nor much broad band imaging to be honest. (See https://stargazerslounge.com/uploads/monthly_2022_07/Light_M13_60.0s_Bin1_gain100_20220710-000225_-10.0C_0035.jpg.88e32ed0ffb2485f5b03680e154ecd51.jpg) Ian

You don't need anything together with the L-extreme, but if you plan on using the camera for broadband, then an IR/UV filter as a minimum is desirable as the camera itself has a plain window. It'll tighten up the stars. I can't offer advice on light pollution filters. Ian

Care to share the link? I gather that most dual band filters cause star halos, though one or two of the more expensive ones claim not to. I'm thinking of the Antlia Gold. Star removal certainly brings the target to the fore. Ian

Cracking shot! But you do have to put in the hours. Where do you find them all in our climate? Ian

What a fantastic rendition - the detailed, almost turbulent, dust clouds peeping through the mist! Ian

Just a heads up, they say to write what lead length needed in the notes box, but it wasn't obvious where the box is. I needed to tick a tick-box in order to reveal it. Ian

I've just bought a couple from them. What I liked was that they offer a 2.1mm plug option, which allowed me to plug straight into my ASIAir, and they can provide the lead length needed, so I din't have to have 2m of lead to try to stow neatly. They seem well enough made and they work, though I've only used them once so far. I'd have no hesitation in buying again. Ian

Nice rendition so far and looking forward to the colour being added. Would you mind indicating what scope and camera you are using please? Nice to see that the 'dark stuff' is showing well. Ian

I've finally got around to processing the session from 25 August where I've almost doubled the amount of data on this target, previously posted here. The colours are slightly different, but the extra 'solidity' given to the image is noticeable. Imaging details - Askar FRA400, ZWO AM5 mount, L-Extreme dual band filter Lights 62 x 300s in 2 sessions (5.1hrs total) 30 x Darks, 50 x flats and flat-darks Dates 11th and 25th Aug 2022 Ian