Print Settings for Prints

I have the same issues.  In trying to chase this down, I have learned from different YouTubers, the images for printing should be a bit "over-exposed" due to the inherent differences between digital projection (i.e. led monitors) and printed colors.  Also, I think the material used for printing matters greatly.  Metal prints are much brighter than paper prints.  That said, it would be great of others with more knowledge than me provided guidance on this thread.  Hope this helps.

Best thing you can do is find a competent print shop who knows their own printers and have their RGB to CMYK conversions dialed in. If you go that route then you don't have to do anything special. Print media is in a subtractive colorspace whereas stuff on a screen is additive. Getting the conversion right is much more difficult then people imagine. I mean, getting three different monitors to agree is already hard enough, and even if you manage that, a month later they will start to drift apart. Now throw pigment and paper into the mix.

Find a professional local print shop and do some tests.

They make calibrators for the monitor and printer. High quality monitors, that most of us do not have, can be tuned very well for printing. 
the rest of the monitors (mainstream) can be adjusted very close to perfect using said calibrators. 
they scan certain colors on the monitor and again after they are printed and they create an image profile for the monitor/printer combo.

I've seen this video in the past where @Nico Carver shares an interesting approach on how to print photos: 

https://www.youtube.com/watch?v=6teO7e6EhBk&list=PLrzbdmripj1d0shhKaPsv6XjEmjdsiGix&index=2

Great video, thanks

@Jean-David Gadina Thanks for that detail. I think I have to use Photoshop for that, but that's fine. I am going to look into a local printer, who can hopefully make the necessary adjustments.

Please do not perform CMYK separation on your own. If you don‘t know what you are doing you will ruin your picture. Modern fine art printers use more inks than 4 colors therefore separation has to be done in the rip software before the printer. All print service provider will ask you to provide your file in RGB.
Please ensure you have an ICC profile embedded in your file. If you have colorprofiles for softproofing from the provider use them for softproofing only. Don‘t embed or convert into that profile.

I‘m working for the photolab whitewall.com but I don‘t want to do advertising here. I have done lot‘s of prints with my own astro images and I must admit that astro images are really special in printing. A few tips:

1. invest in a good monitor capable of hardware calibration and calibration kit. 

2. use softproof profile and turn paper white simulation on. Image will look very dark and this is due to the difference in dynamic range between paper  and monitor. 

3. make a curve adjustment to increase the midtone levels until it looks fine with paper white simulation. It might look a little bit extreme on monitor but that‘s ok

4. Don‘t change the colorprofile of your image unless you know what you are doing. A good lab will handle it correctly

5. if you are printing the first time order a hardproof to ensure you are happy

6. don‘t upscale the image yourself. The photolab will have better tools for that

7. Disable automatic image enhancement for your print order

And a last personal recommendation: photochemical prints may look better than inkjet prints because they reduce noise. I personally found Fuji Pearl paper the best for astro images because it‘s a metallic paper where there will be an optical glow effect on bright parts of the image (=stars). It has very good contrast too.

best,
Markus

Pro photographer here - much good advice offered above already. 

- Work with a pro lab and use their specifications - e.g., Adobe 1998 RGB colour space, 300 dpi, etc.
- Get a monitor calibration device, spyder or similar and calibrate your monitor to match the lab's specs - otherwise, it's like driving at night without headlights; you can't see where you're going!
- Get a narrow test strip done before ordering wall-size prints (usually under $10) and see how it looks, then adjust colour/density as and if required.
- If your lab has it, Fujiflex is incredible for Astrophotography images. Alternatively, metal prints are brilliant, too.
- No affiliation but Bay Photo does great work in the USA, Print2Metal does in Australia.

CS
Andy