[TerryL]

Hello Folks,
I am trying to pick out an online printing service. So, I am wondering if the typical printing service can print at the resolution that I get from my K-1 and better lenses shooting in Raw?
Thank you,
Terry

[fehknt]

short answer: yes.

long answer: well, I don't know that it's quite the right question to ask and the right question all depends on what size you are printing. You have some constant #pixels and depending on the area they are spread out over, it'll be either low or high resolution (which is often used interchangeably between total display dots and per-unit-area measures but I believe is more technically correct in per-unit-area).

A common way to think about this is to ask the reverse: "If people will look really closely at my print, I'll want the resolution to be 300dpi, so for the K-1 pixels (7360x4912) I can print at most 24.5x16.4 inches before it will look low resolution to the viewer." And you pick the dpi measurement depending on the expected viewing distance -- a billboard is super low resolution actually but you never notice because the viewing distance is so long that you can't resolve the pixels.

Of course, that's just the upper bound on print size, anything smaller will look good too.

Or, maybe you are asking if you print small at 4x6 if the full file will actually have every pixel individually resolved. Depends on the printer I suppose but generally, no, the ink droplets are too big and I believe the highest "normal" prints can resolve is between 200-350 dpi. There's a lot of printers out there that claim higher resolution but if I understand what's happening there it's a matter of positioning accuracy and the ink droplets will soak/spread a bit so even though they aren't lying exactly about the resolution that they can print at -- it does help produce more even tonal gradients etc. -- it doesn't help much reproducing super fine detail as it would on a screen where pixels are nearly perfectly separated from each other.

[SharkyCA]

This may not answer your question but it will give you a lot of info on printing your images.
https://www.digitaltrends.com/photography/how-to-print-digital-photos/

[TerryL]

short answer: yes.

long answer: well, I don't know that it's quite the right question to ask and the right question all depends on what size you are printing. You have some constant #pixels and depending on the area they are spread out over, it'll be either low or high resolution (which is often used interchangeably between total display dots and per-unit-area measures but I believe is more technically correct in per-unit-area).

A common way to think about this is to ask the reverse: "If people will look really closely at my print, I'll want the resolution to be 300dpi, so for the K-1 pixels (7360x4912) I can print at most 24.5x16.4 inches before it will look low resolution to the viewer." And you pick the dpi measurement depending on the expected viewing distance -- a billboard is super low resolution actually but you never notice because the viewing distance is so long that you can't resolve the pixels.

Of course, that's just the upper bound on print size, anything smaller will look good too.

Or, maybe you are asking if you print small at 4x6 if the full file will actually have every pixel individually resolved. Depends on the printer I suppose but generally, no, the ink droplets are too big and I believe the highest "normal" prints can resolve is between 200-350 dpi. There's a lot of printers out there that claim higher resolution but if I understand what's happening there it's a matter of positioning accuracy and the ink droplets will soak/spread a bit so even though they aren't lying exactly about the resolution that they can print at -- it does help produce more even tonal gradients etc. -- it doesn't help much reproducing super fine detail as it would on a screen where pixels are nearly perfectly separated from each other.

Of course you're right, It will depend on the size of print. I should have mentioned that. Anyway, I will be printing at 5X7 and 8X10. Thank you for your reply.
Terry

---------- Post added 09-21-18 at 10:00 AM ----------

This may not answer your question but it will give you a lot of info on printing your images.
https://www.digitaltrends.com/photography/how-to-print-digital-photos/

I love that article. I saved it on my desktop so I can read it several times. Thank you very much.
Terry

[pschlute]

24" by 16" print I had done. prepared the file at 300 ppi for the printers. This is only an iphone shot but it looks terrific in the flesh.

[TonyW]

Hello Folks,
I am trying to pick out an online printing service. So, I am wondering if the typical printing service can print at the resolution that I get from my K-1 and better lenses shooting in Raw?
Thank you,
Terry

Depends on your online printing service, their services and requirements for file submission, which should relate directly to the printer requirements.

For Canon/HP/Fuji you can expect a required standard resolution of 300 ppi and if native size above this 600 ppi will get the optimal quality assuming image is first rate and has the necessary IQ in the first place

Epson printers tend to use 360 and 720 ppi.

Whatever else happens in the print pipeline the print driver will resample your data to match its declared resolution 300/600 or 360/720. Using its own resampling algorithms which designed for speed, likely to be nearest neighbour.

You can use superior algorithms in applications such as PS and LR plus many others which may prove better in handling your image data

Typically in my experience many labs will use the lowest resolution when specifying file requirements. Nothing particularly wrong with this but if you have the native resolution and the subject matter contains strong lines diagonal and circular the higher resolutions may exhibit improvements and not leave IQ on the table.

[TerryL]

24" by 16" print I had done. prepared the file at 300 ppi for the printers. This is only an iphone shot but it looks terrific in the flesh.

Hi Peter,
I recognize that picture. It's a great one, and taken with your 15-30 with a Lee ND filter. Looks great on your wall. Thanks for replying.

[pschlute]

Hi Peter,
I recognize that picture. It's a great one, and taken with your 15-30 with a Lee ND filter. Looks great on your wall. Thanks for replying.

I should have added that you should be guided by the requirements of your chosen printing company. At 300ppi which seems a popular requirement, a 5x7 print will require an image 1500x2100 pixels.

Here in the UK there are a number of companies who do quality prints but at reasonable prices because they require you to resize your images before you upload them. With modern computer software this is not beyond the abilities of the amateur.

[runswithsizzers]

Be aware that most online printing services don't want anything to do with your raw files. It's up to you to pre-process your raw files and then upload either a JPEG (most common) or TIFF. Each online printing service may have it's own list of supported file types.

You may also need to decide if you want to take total responsibility for control over colors, sharpness, etc. or if you want to allow the printing service to "improve" your photos according to their experience and software. If you are a black-belt Photoshop master using advanced color management protocols, then have it your way. If not, then I'd turn it over to the pros.

The print sizes you want could easily be done from MUCH lower resolution cameras than your K-1, so that is not even close to being an issue.

[PDL]

Things you should do at the outset.

1. Calibrate your monitor.
2. Make sure your print service does not "autocorrect". This is usually placed in a spot labeled for "professional users", unless you are using a real professional print service where they expect you to "know".
3. Get the printer drivers from your print service and use them. (If you don't know about embedding printer information into your output file --- well look it up)
4. Send the exact size of the image to be printed. Don't let the print service crop - see point 2.

Make sure that you send the highest quality image to be printed. If possible go to the place where the image is printed and look at it before you accept it. I did this at my local Costco because there was a blemish on the paper and it took them less than two minutes to print me another copy without a blemish.


And yes, I have printed 20x30 inch images from a 6MP *ist Ds that look great.

[Take-5-JB]

Caveat: I am not a mathematician, an optical engineer, or a Physicist. I am a retired Chemist.

My thought process is that resolution is one question (ppi) and size is another. Native resolution is based on sensor pixel population (10mp, 16mp, 24mp, 36mp, etc). Files in JPEG out of different model cameras with sensor sizes that differ may be at 72, 150, 200, 300 ppi depending upon the size it spreads the native pixel population over. Raw holds all that is possible and TIFF retains higher density than JPEG. Once you establish the necessary limit for what you want by taking the observer distance into consideration (288 ppi is optimal for the human eye even close up, but not with a magnifying glass or microscope). Then you can use any of a plethora of sizing algorithms that meet your needs. This allows you to expand your image at the set resolution to larger sizes than the native sensor pixel population would support.

I have historical files from 2 or 3 MP (copied film) and 5 mp digital up to the latest from my K1 (36mp at 300 ppi is a little better than 16x24 inches). You will reach an expansion limit, but the larger the native size the better the image will "expand" at a set ppi. If you want your best view, use 288 ppi minimum. I use 300 ppi resolution. If you have 72,150, or 200 ppi you will have to de-noise at some point, and even with 300ppi if you expand too large.

I recently sold a 48 x 72 inch canvas image to a client that contracted with me to make a specific landscape. I captured the image with the K1 and made some clean up in post processing, resized it, de-noised, and produced a 60 x 90 inch at 300 ppi. This file was 172 MB. My outside print shop can handle up to 200 MB files. The size was overkill and unnecessary, but I usually send a larger image so in reality they get greater than 300 ppi when they size it to print. I know it is not necessary but I like to provide 350 to 450 ppi at the requested print size.

I hope this rambling makes sense. and to all you optical or digital engineers...see my caveat.

JB

[TonyW]

FWIW my thoughts on this:

An image file does not have a size only a pixel count in the x and y directions this applies to raw, JPEG, TIFF etc. So all files will have the same pixel count but the loss in quality associated with JPEG is down to the way the algorithms discard information (not pixels). My understanding is that colour information is first to be dropped then luminance as required by the amount of compression applied. TIFF will not generally drop any information in the most popular compression algorithms.

You can calculate ppi requirements quite easily with a very simple formula minimum ppi = 3438 / Viewing Distance. Assuming someone with 20/20 vision. So if we know that our print is going to be viewed ideally from 8" away then the minimum ppi calculation reveals a need for 430 ppi. Bear in mind however that these figures are for 'average' lighting conditions, high contrast optimal lighting these figures can easily be doubled

300 ppi is often touted as the resolution of the human eye hence the just as often stated that we do not need more than 300 ppi in print.

The human eye can under good conditions resolve objects slightly less than one arc minute (assuming 20/20 vision). At a distance of 10 inches 1 arc minute corresponds to 0.003 inch the inverse therefore equal 344. It takes at least two pixels to resolve something therefore we are looking at around 700 ppi as the eyes resolution – but the eye can actually do better than this!

So starting with a good image contain lots of detail you should be able to see the difference between prints with the image set to 150 ppi, 300 ppi and 600 ppi. Note these are standard resolution for most Canon/HP/Fuji printers. For Epson you would substitute 180 ppi, 360 ppi and 720 ppi. Ideally we would use these figures and upsample in our favourite image editor to ensure optimal IQ over just allowing the print driver to upsample generally using the poorer Nearest Neighbour resampling.

Apart from seeing the difference myself with actual prints many others have documented these facts on the net. May be worth trying for yourself with your particular printers?
Worth mentioning viewing distance. Stand far enough away from a print and you will not see the differences that higher ppi values bring. But most of us will tend to look quite closely at a print that interests us and if compared side by side detail will be revealed in the higher ppi version most of the time. Print surface will also have a bearing on resolving detail rougher / textured surfaces may only require half the ppi of gloss semi gloss.