Upscaling for printing

[cbbella]

Hi, i want to get a large print (36x36inches) of an image of the moon i took.  After processing in autostakkert3, registax and lightroom i ended up with my image but i'm not sure if i've overprocessed it.  it looks great on a computer screen but if i zoom in i can see what i think you call noise(i'm new to this so i think this is what i am seeing), see attached photos.

When exporting the image in lightroom i resized it to 36x36 inches which lightroom upscales so the print will still look good(i think) for larger printing in a local shop.

My question is would this noise show up on a larger print or am i only seeing it because i have zoomed in on the computer.  The print shop said it may cost between £30 to £40 but i don't want to let them go ahead and print it only to find out i can see a load of noise as i would then have wasted my money
 

i have attached the original .tif, the processed, the enlarged processed and the zoomed in .jpg files

p.s.  i'm new to this and have been following youtube videos on processing so if anyone can help make my original.tif image better and upscaled to 36x36 inches it would be much appreciated

original.tif

Edited June 10, 2020 by cbbella

[pc387]

Hi I've been trialing a photo enlargement software from Topaz labs (Gigapiixel AI) and have been blown away by the results;, certainly on terrestrial  photos' where I've heavily cropped an area of interest and noise is very evident. 

However after up scaling  the noise virtually disappears and the detail remains. May be worth a try (there's a 30 day trial, and the software is fully functional, and is very intuitive to use).

pc387

[CloudMagnet]

Its always a good idea to look at the pixels per inch as well. The higher the PPI, the less you can see the individual pixels so the better the image will look once printed.

I would aim for at least 200-250ppi to give decent results, 300 being ideal. With your tif file, its shows at 72ppi, scaling that to 200ppi gives a print of 20x15inches roughly. At 36 inches, there will be too much pixelation so I wouldnt go ahead until it was scaled up.

[cbbella]

On 13/06/2020 at 14:26, CloudMagnet said:

Its always a good idea to look at the pixels per inch as well. The higher the PPI, the less you can see the individual pixels so the better the image will look once printed.

I would aim for at least 200-250ppi to give decent results, 300 being ideal. With your tif file, its shows at 72ppi, scaling that to 200ppi gives a print of 20x15inches roughly. At 36 inches, there will be too much pixelation so I wouldnt go ahead until it was scaled up.

thanks for pointing that out.   i thought i was doing the upscaling in lightroom - see attached screenshot.

do i scale the dpi up when stacking in autostakkert

 

Edited June 14, 2020 by cbbella

[CloudMagnet]

19 hours ago, cbbella said:

do i scale the dpi up when stacking in autostakkert

Im not sure that is upscaling, just resizing the image to a smaller size but higher PPI. I think you will need dedicated software like what @pc387 suggested to enlarge the image at the same resolution.

[cbbella]

ahh ok,  i'll give that a try, thanks

[cbbella]

On 10/06/2020 at 08:54, pc387 said:

Hi I've been trialing a photo enlargement software from Topaz labs (Gigapiixel AI) and have been blown away by the results;, certainly on terrestrial  photos' where I've heavily cropped an area of interest and noise is very evident. 

However after up scaling  the noise virtually disappears and the detail remains. May be worth a try (there's a 30 day trial, and the software is fully functional, and is very intuitive to use).

pc387

thanks for the suggestion, i'll give that a try

cheers

[MartinB]

One thing to bear in mind is that looking at a poster is very different to looking on a monitor.  People don't normally get up as close and aren't looking for noise.  If it looks noisy close up most people, unless they happen to be astro pixel peepers, will take a step back.  Pixelation on the other hand is a nasty artefact which will degrade the image so, as has been said above, make sure your image has an adequate pixel count.  Of course, keeping noise to a minimum is always desirable as long as it is well achieved rather than by excessive smoothing.