Printing question

[Anthonyexmouth]

Popped into a local printer today. Thinking about getting the odd nice image printed. I pointed to a print size of 12x16 as the kind of size I was looking for. He said the image would ideally be 300dpi but at least 150dpi, now I've just looked at a tiff save from Pixinsight and it seems to be 72dpi. Am I reading it wrong? Is my 11mp 294 not capable of a print that size? 

Never done any serious photo printing so unsure on this one. 

[Lee_P]

DPI is dots per inch. You can change an image's DPI in software like Photoshop. If you're not sure how, feel free to send me your image and I can do it for you. Your camera is certainly capable of producing 12x16" prints 👍

Edited February 15, 2023 by Lee_P

[Anthonyexmouth]

5 minutes ago, Lee_P said:

DPI is dots per inch. You can change an image's DPI in software like Photoshop. If you're not sure how, feel free to send me your image and I can do it for you. Your camera is certainly capable of producing 12x16" prints 👍

Oh I get what DPI means, doesn't it just decrease the bigger the image gets printed? Why does windows report it as 72dpi. why not just report the pixel resolution? 

[CraigT82]

The 294 sensor is 4144x2822 pixels so printed at 300dpi it would be 13.8” x 9.4” in size. Double that for 150dpi.

72dpi is just standard screen display resolution 

[Anthonyexmouth]

Cool. So no issues with the size I wanted. 

Is high quality home printing really viable on a budget at that size? Or is print shop the best way? 

[ollypenrice]

Start with your unreduced, processed final TIFF in Photoshop. Use the crop tool to set the proportions you want to end up with, so 12x16. (This crops to a proportion, not to a final size.)

Go to image, size and uncheck resample.

Set the dimensions to cm or mm, not pixels. Set these dimensions in the appropriate boxes.

See what PPI value this gives you. It's shown on the screen.

If it's enough for the printer, fine. It should be.

If it's not, check resample and next to that choose Preserve Details (enlargement.)

Type in the PPI you want.

 

The other thing to remember is the colourspace. The printer needs to know which one you are using. The internet standard is sRGB but it isn't the best to work in. I process in ProphotoRGB and print from that but, for the net, I go to Edit-Convert to Profile (note, not Assign Profile) and choose sRGB if that's what the printer wants. If you're not sure what colourspace you're using in Ps, go to Edit - Colour Settings and see what colourspace is there in your working spaces. It should be OK just to tell the printer what you're using.

It's always best to do a small test print first because, with the best efforts in the world, getting the screen and the paper to match up is not dead easy!

Olly

 

[ollypenrice]

3 minutes ago, Anthonyexmouth said:

Cool. So no issues with the size I wanted. 

Is high quality home printing really viable on a budget at that size? Or is print shop the best way? 

I use an ink tank Epson 15000. The bottled inks are really not expensive and go a very long way. It can print up to extended A3 and, although it's only a 4-ink machine, I find the prints to be excellent - and I'm fussy. Because I can do a small test print first, this beats hoping for the best with a third party service.

Olly

Edited February 15, 2023 by ollypenrice
clarification

[vlaiv]

24 minutes ago, Anthonyexmouth said:

Oh I get what DPI means, doesn't it just decrease the bigger the image gets printed? Why does windows report it as 72dpi. why not just report the pixel resolution? 

If you measure diagonal of your screen and divide that with number of pixels on that diagonal (~2202 for 1920x1080) - you should get one of standard screen resolutions like 72ppi / 96ppi (pixel per inch)

You have what you have in terms of pixels in your image - say that you have 4144x2822 px image from that sensor (although it won't be that after stacking / processing and cropping stacking artifacts) - you can print it in which ever resolution you want to print it - say you want to print it in 300dpi

Then resulting image will be 4144/300 = ~13.81"

x

2822 / 300 = ~9.4"

If you print it in 150dpi - then you will have twice as large image - or 27.6" x 18.8"

So what is the resolution you should print it in?

That depends on intended use of the image. A bit of math here follows.

Humans usually resolve 1 arc minute, so we can use that as pixel size.

What distance will the image be viewed at? Will it be hand held and viewed at reading distance? That is about 20-30cm. Will it hang on the wall? That is about 50cm

Will it be poster on the street to be viewed from 2 meters away?

In each case - we can determine print resolution that is needed for image to look good. Let's take wall example - 50cm

At 50cm, 1 arc minute is 0.14544 mm wide - or 25.4 / 0.14544 = 174 pixels per inch.

In this case - I would say that 150dpi is sufficient. For half that distance, or hand held version - you'd want to use 300dpi (that is why those two are printing standards)

For poster at 2m away - you can actually use only ~50dpi and it will look good at that distance.

[Anthonyexmouth]

That all makes good sense. So definitely nothing to worry about with my images then for wall hanging. So far I've only printed a few with a 6x4 canon selphy printer. They churn out a nice print but craving something bigger now. 

[Anthonyexmouth]

13 minutes ago, ollypenrice said:

Start with your unreduced, processed final TIFF in Photoshop. Use the crop tool to set the proportions you want to end up with, so 12x16. (This crops to a proportion, not to a final size.)

Go to image, size and uncheck resample.

Set the dimensions to cm or mm, not pixels. Set these dimensions in the appropriate boxes.

See what PPI value this gives you. It's shown on the screen.

If it's enough for the printer, fine. It should be.

If it's not, check resample and next to that choose Preserve Details (enlargement.)

Type in the PPI you want.

 

The other thing to remember is the colourspace. The printer needs to know which one you are using. The internet standard is sRGB but it isn't the best to work in. I process in ProphotoRGB and print from that but, for the net, I go to Edit-Convert to Profile (note, not Assign Profile) and choose sRGB if that's what the printer wants. If you're not sure what colourspace you're using in Ps, go to Edit - Colour Settings and see what colourspace is there in your working spaces. It should be OK just to tell the printer what you're using.

It's always best to do a small test print first because, with the best efforts in the world, getting the screen and the paper to match up is not dead easy!

Olly

 

That's all sounding like really great advice, but alas, I don't have Photoshop. Although I might have an older pooched copy laying around on the nas. Just couldn't bring myself to pay for the subscription. I don't have much experience with it anyway, played around with lightroom a bit but can't remember any of it. 

[Anthonyexmouth]

17 minutes ago, ollypenrice said:

I use an ink tank Epson 15000. The bottled inks are really not expensive and go a very long way. It can print up to extended A3 and, although it's only a 4-ink machine, I find the prints to be excellent - and I'm fussy. Because I can do a small test print first, this beats hoping for the best with a third party service.

Olly

I've got an older canon pixma mg6350 6 cartridge printer. Never tried photo printing with it though. Maybe I should, any recommendations for paper? Advertised spec is

• Print/Scan/Copy.
• Up to 15ipm Mono Print.
• 9600 x 2400 dpi Print.
• Up to 10ipm Colour Print.

 

 

[wongataa]

15 hours ago, Anthonyexmouth said:

Cool. So no issues with the size I wanted. 

Is high quality home printing really viable on a budget at that size? Or is print shop the best way? 

Home printing isn't really viable unless you do a lot.  High quality photo printers aren't cheap and larger format ones are even more expensive.  If you don't use them regularly the inks will dry out etc making it even more expensive as you keep having to throw ink away every time you print.

Then there is the learning curve on getting good prints.

For occasional prints it is best to just send files to a print shop.  They will have more paper options than you could have at home and the quality will be good. Order a small test print first to check things out.

Regarding DPI, the DPI number in the image file is just a number in the metadata.  It doesn't mean anything really and can be changed without affecting anything else.  What matters is the pixel dimensions.  Divide the number of pixels down one edge by the appropriate dimension of the print size you want and see what the result is.  This is the number you want to be close to 300 ideally.

[jacko61]

18 hours ago, ollypenrice said:

I use an ink tank Epson 15000. The bottled inks are really not expensive and go a very long way. It can print up to extended A3 and, although it's only a 4-ink machine, I find the prints to be excellent - and I'm fussy. Because I can do a small test print first, this beats hoping for the best with a third party service.

Olly

What paper do you use Olly?

Graeme

[ollypenrice]

9 minutes ago, jacko61 said:

What paper do you use Olly?

Graeme

Epsom Premium Glossy.

Olly

[Anthonyexmouth]

On 15/02/2023 at 20:26, ollypenrice said:

I use an ink tank Epson 15000. The bottled inks are really not expensive and go a very long way. It can print up to extended A3 and, although it's only a 4-ink machine, I find the prints to be excellent - and I'm fussy. Because I can do a small test print first, this beats hoping for the best with a third party service.

Olly

I liked the idea of the tanks but went for the cheaper XP-15000 and so far happy with it. I did think glossy paper would be best but speaking to fotospeed they advised semi gloss/lustre. Just wondering how you find the gloss. I'd have thought gloss would look nicer but I really do know nothing about photo prints. Only using A4 at the moment while I get the hang of it but cant wait to do a nice bit A3+ print. 

[jacko61]

I ended up going for the 6 ink Epson ET-8550.  I'm printing on Epson premium glossy A3+ and I've been very pleased with the results. Mrs J has said she'd be happy to mount a few and put them on the walls which says more for the quality than online reviews ever could. 

Graeme

 

[Anthonyexmouth]

4 minutes ago, jacko61 said:

I ended up going for the 6 ink Epson ET-8550.  I'm printing on Epson premium glossy A3+ and I've been very pleased with the results. Mrs J has said she'd be happy to mount a few and put them on the walls which says more for the quality than online reviews ever could. 

Graeme

 

I got some A3+ paper the other day but waiting for the custom profile to get to me before I print. I'd like to try some of the metallic lustre paper, I got a sample and it looks really nice.