pixels per inch for printing

[Joseph27096658zjkc]

So I am new, So please be kind 🙂

My Nikon is a 47.5MP camera. I shoot in Jpeg/Raw

I have a pic that has been converted to the psd file format. It is 74. MP

I open in Adobe photoshop

I look at image size and for a 50X30 it shows its only 134 pixels per inch

From my math a 5X30X300 is a little over .5 MP

Why wont it show up as a higher resolution?

I have a cannon pro 6100 and i want to be able to print the full width at 300. What am i doing wrong?

Probably many things, so far this has been a lesson in humility and patience 🙂

Any help would be greatly appreciated. I have been reading everything i can find and watching tutorials as well.

Kind Regards, Joe

[Stephen Marsh]

Please provide original image dimensions in pixels and cropped or resized dimensions in pixels.

How will the images be printed? Inkjet? What is the viewing distance? You probably don't need 300ppi at final size.

[PECourtejoie]

hi, I guess it is a D850 or a Z7. The D850 has a resolution of 8256 x 5504 px.

8100/300 is 27 inches, while 5400/300 is 18 inches.

You can use the super resolution in Camera Raw ( https://helpx.adobe.com/camera-raw/using/enhance.html) to double each dimension, and get a 54x36 inches image at 300PPI, which is very close or exceeds what you want.

[Lumigraphics]

What will the viewing distance be? Have you tried a test print to see how it looks at original size? It will look fine if you are viewing it from several feet away.

[Derek Cross]

Bear in mind that what PECourtejoie has clearly explained, that 300PPI is the recommended resolution for producing artwork for images to be reproduced in magazines and books that are read relatively closeup. Larger sizes, that are used for things like posters that are read from a distance, can have a much lower resolution.

[PECourtejoie]

Indeed, I was replying to the mathematical part of the Question, assuming that the OP absolutely needs that resolution.

I've been very surprised by the quality of prints with way smaller resolution on a plotter. If there is not too much jpeg compression, usually, images scale pretty well. But as soon as jpeg blocks are there, it's pixel soup.

But here, @Joseph27096658zjkc starts from a very high resolution NEF image...

I'd try printing a part of the image at super res, at final size, and the same part, scaled by Ps, or by the printer driver at the regular resolutin, as the DNG produces by super resolution are HUGE.

[davescm]

A 50 x 30 inch document at 134 pixels per inch will be 6700 x 4020 pixels = 27 MPixels which is short of the MP count from your camera. Also the aspect ratio is different to the normal 3:2 ratio so something is off.

Can you confirm :

a. The camera model

b. How you converted RAW to PSD - was any cropping involved?

c. Take a screenshot of the PSD showing Image >Image Size dialogue.

Dave

Dave

[Joseph27096658zjkc]

Nikon d850

I originally brought in as a nef

original size per the dialogue box is 6768X4016

I had saved the changes as a psd in photoshop.

I am sorry, but I am still learning the language. I thought if an image was brought in as a nef that would make it

a higher resolution as there are more MP to work with.

I open the raw and then save it as an nef.

I think I am struggling to understand the resolution thing. I thought it was width X length X the pixels per inch that i wanted so 50X30X300= 540000 pixels or is that supposed to be megapixels?

I apologize for my ignorance. 🙂    Joe

[davescm]

Hi

A D850 should allow you to take raw images at 8256 x 5504 which is 45.4 M Pixels.

When you open a NEF file in Photoshop you are opening it in a plug in called Camera Raw. When you are finished making adjustments for the conversion from Raw you click Open to open the file in Photoshop from where you can save it as a PSD. However, before clicking open (still in camera Raw) check at the bottom of the Window and you should see some settings for Color Space - bit depth and size. Click on that and you will get a dialogue for image sizing. Make sure that is set to match the full pixel size from your camera.

Of course if you have cropped the image in camera raw, the size will be reduced.

The size in pixels is length x ppi x height x ppi so in your example 50 x 300 x 30 x 300 = 135 M Pixels

Dave

[Joseph27096658zjkc]

Thank you to everyone 🙂  I appreciate you sharing you hard earned knowledge. I figure many on this site have  hundreds if not thousands of hours perfecting their knowledge so sharing that is no small thing!!!  Thanks 🙂

I will try what you said when i get home.

The difficult part of this process is i dont even know what i dont know. So most of the time i am not sure what to even ask. UGHHH!!!

Thanks again and have a great day !      Regards, Joe

[D Fosse]

As PECourtejoie points out, a D850 has a native sensor resolution of 8256 x 5504 pixels. So you have somehow cropped or resampled the original file.

At full native resolution, a file from a D850 has enough pixels for anything. You could put that up on a roadside billboard.

The ppi you need depends on size and viewing distance. You don't need 300 for large size reproduction! A wall-sized banner or billboard can be 10 ppi and look perfectly sharp, because it will be seen from farther away.

There is no need for any super resolution or super zoom or any upsampling at all.

[Lumigraphics]

One more suggestion, I have a 50MP Canon 5Dsr and getting sharp photos requires good technique. Use a tripod or stabilized (VR) lens if possible, at a middle aperture, and the best combination of lighting and low ISO setting possible. I've been a photographer for almost 40 years including everything from 110 to 4x5 film to digital and the 5Dsr has really made me pay attention to my technique, far more than my previous main camera, the 20MP Canon 6D.

45 or 50MP of mush will not print well regardless of settings.

[Joseph27096658zjkc]

I agree. I am going to take some private lessons.  This is like tring to teach a child that hasn't learned how to walk yet and teaching them to do brain surgery 🙂

[D Fosse]

Yes, what Lumigraphics says is what all of this boils down to. Getting a good quality shot is far more important than the number of pixels. Concentrate on that.

Lots of pixels is nice, but worth nothing if it's out of focus, has motion blur, is shot with an inferior lens, etc.

One thing you'll notice with these high resolution sensors is that there's no such thing as depth of field. The plane of critical focus is paper thin, even stopped down.

[Lumigraphics]

And you'll be diffraction-limited by about f/8-11, so stopping down too far isn't great either. Practice and keep improving your craft.

[NB, colourmanagement]

D Fosse, is that your image, what a bloody great illustration of how viewing distance works. 

neil

[NB, colourmanagement]

When seeing the image with low resolution - are you looking at a processed RAW or the Jpeg the camera created?

I hope this helps
neil barstow, colourmanagement net :: adobe forum volunteer:: co-author: 'getting colour right'
google me "neil barstow colourmanagement" for lots of free articles on colour management