Resolution Problem.
Discussion
A small local charitable association were asking for people to send in pics of the area with the view to producing a "low-key" calendar. I sent in about a dozen.
I have just been told that 10 of the 12 have been rejected by the printers because the resolution wasn't good enough.
I'm puzzled.
All pics were taken with a 450D as landscapes.They were cropped and sent by e-mail to the organiser (uncompressed further)two at a time because some were 6+ MB.
The two that were ok were 3.73MB and 5.8MB and were sent in different e-mails. All the 6+MB were rejected.
As far as I can gather the printers' minimum requirement was 1600x1200.
I wonder if someone could please suggest where I have gone wrong?
As you know the technical side of things is not my strong point.
I'm not bothered about the photos not being "aired" but the calendar has had to be cancelled for this year. They plan to try again next and I don't want to repeat my mistake.
Thankyou.
I have just been told that 10 of the 12 have been rejected by the printers because the resolution wasn't good enough.
I'm puzzled.
All pics were taken with a 450D as landscapes.They were cropped and sent by e-mail to the organiser (uncompressed further)two at a time because some were 6+ MB.
The two that were ok were 3.73MB and 5.8MB and were sent in different e-mails. All the 6+MB were rejected.
As far as I can gather the printers' minimum requirement was 1600x1200.
I wonder if someone could please suggest where I have gone wrong?
As you know the technical side of things is not my strong point.
I'm not bothered about the photos not being "aired" but the calendar has had to be cancelled for this year. They plan to try again next and I don't want to repeat my mistake.
Thankyou.
I had a funny experience with a printer for a calendar, they said as long as the resolution was 300dpi it didn't matter about anything else. I pointed out that I could sent them one pixel at 300 dpi but they still didn't get it. Maybe your printers are the same, they just check the dpi and didn't bother looking at what they really had.
You said you cropped the images. It's unlikely but did you crop them smaller than 1600x1200px?
Presume you sent JPGs and that's what they wanted?
Other than that I can only suggest you ask them what they mean by 'resolution'. They could be using it to mean out of focus or wrong aspect ratio (a possibility if you cropped them)
Presume you sent JPGs and that's what they wanted?
Other than that I can only suggest you ask them what they mean by 'resolution'. They could be using it to mean out of focus or wrong aspect ratio (a possibility if you cropped them)
I think Nick may be on the right track. A lot of publishers ask work to be submitted at a minimum resolution of 300dpi, but without specifying how large the final output is going to be, how can you work out what that translates to in pixels? If the files you submitted exceeded 6mb I'm pretty sure they would have been ok for the intended use, but if all they looked at was the embedded dpi, which is 72 as default on most cameras, they probably rejected them without checking what they really had.
Two of the files were accepted (assumimg they were taken with the same camera). All my Nikon DSLRs have a default dpi of 300dpi; presume Canon are the same?
Even if not, if it's just the DPI Monster pop into Photoshop and change the dpi to 300. Shazam. So simple even a printer could do it! Well possibly not.
Even if not, if it's just the DPI Monster pop into Photoshop and change the dpi to 300. Shazam. So simple even a printer could do it! Well possibly not.
DIW35 said:
I think Nick may be on the right track. A lot of publishers ask work to be submitted at a minimum resolution of 300dpi, but without specifying how large the final output is going to be, how can you work out what that translates to in pixels? If the files you submitted exceeded 6mb I'm pretty sure they would have been ok for the intended use, but if all they looked at was the embedded dpi, which is 72 as default on most cameras, they probably rejected them without checking what they really had.
Probably this. I've even known photographic magazines misunderstand it. But check that, when you cropped, you didn't accidentally input a lower resolution. If you did it in Photoshop, open the toolbar and check the settings.
Just back in. Thankyou for your replies.
I recognise the figure of 300ppi. I've now found out it came from the printer.
Properties in windows gallery states 72ppi on all pics.
I don't think I have overcropped.
So it appears that if I change that to 300ppi in PS everything will be fine?
I have PSE 9 and I might be able to do it.
Will give it a go tonight.
I was just confused as to why two of the lower MB pictures passed while the higher ones failed. Possibly different people looked at them one purely at the ppi and the other at the overall picture.
I recognise the figure of 300ppi. I've now found out it came from the printer.
Properties in windows gallery states 72ppi on all pics.
I don't think I have overcropped.
So it appears that if I change that to 300ppi in PS everything will be fine?
I have PSE 9 and I might be able to do it.
Will give it a go tonight.
I was just confused as to why two of the lower MB pictures passed while the higher ones failed. Possibly different people looked at them one purely at the ppi and the other at the overall picture.
tenex said:
I was just confused as to why two of the lower MB pictures passed while the higher ones failed. Possibly different people looked at them one purely at the ppi and the other at the overall picture.
It does seem odd. Also odd the images would have dropped from '300' to '72'. But it is exactly the same image. Just go into PS and change it to '300dpi'. It will look smaller but be exactly the same data.The mythical DPI Monster it was then. What a pity it made them scrap the calendar for no reason.
The misunderstanding comes from the days when a printed photograph came from a transparency and was screened (broken up into dots for halftones or colours) to make the film/s from which the plates were made. That's where dpi comes from, and yes, if you have a photo broken down into 72dpi that way you can't improve it. But that was then and this is now...
Give them a sack of King Edwards and see if they can work those
Give them a sack of King Edwards and see if they can work those
Reported file size seems to be only a part of the story. Many printers and certainly most of the agencies other than 'micro-stock' want files of 40Mb or larger. As previosuly observed, this seems to be based on the reauired output for high quality magazine type printing from scanned film.
Typical SLRs have native output files that are around 3000 + pixels wide and although ppi (pixels per inch) and dpi (printer dots per inch when talking about inkjets and similar) are not identical they can work as a reasonable guide.
Monitors tend to work ar 72dpi or 96dpi. Disk space and download time can be saved by having the editor save the files at that resolution. They can also be processed to best suit that resolution if screen output is the expectation.
Printers will typically default to 300dpi (Most manufacturers) or 360dpi (Epson) but will produce output from lower res files and so long as printing at a reasonable size many prints will look quite accepteable at 'normal' viewing distances for the print size at much lower resolutions.
Commercial printers will mostly use completely different types of equipment with their own ppi resolution requirements. From memory 254 ppi seems to be a coomen suggestion. I think that relates to Fuji photo printers but maybe others too.
Many editor programs can provide onscreen information about expected optimum size of output based on current output settings. So if you set an image to 3000 pixels wide at 300ppi the system will tell you that the optimum output size for that file is 10" wide. The file size is, at that point, irrelevant and depsnds as much on the level of detail in the image as it does the pixel dimensions. If you then crop the file the the optimum size is displayed. Change the ppi settings and the max width will change accordingly.
But what if you have cropped the image so that it is too small for the intended final output size no matter what resoltion is set?
Most editors will allow 'up-rez' output whereby you can export the file with size and resolution parameters set and the export will add pixels (making a larger file) to suit the settings. There are many debates about the potential for loss of quality when doing that but I suspect most recent versions of recognised quakity editors would produce a more than good enough result for all but the highest standards of fine art printers. Those with more knowledge than me please comment on that sweeping statement. Basically you are producing a digital enlargement.
I have seen articles that describe how to do this sort of enlargement in multiple steps to retain quality for ultra-large fine art prints to be produced on inklet printers or using older printer devices in a print shop but in the main the articles are about 10 years old. Things seem to have moved on rapidly in both camera sensor pixel count and printer output capability since then and I doubt that many day to day printing requirements really need complex up-rez processing these days.
That said if you sent files set at 72ppi but were asking for, say, 10x8 inch output there may well be a problem with a shortfall of data to up-rez from. The point is that is should be possible to produce the same files alrady up-rezzed to 300ppi working from the original which would be native 300pp one assumes but would be less successful creating a 300ppi file from an original offering only 72ppi (at the intended size) to start with.
I assume GC will be able to provide advice - think he has done some calenders in the past - and perhaps some other who offer commercial print services will chip in too to correct my misunderstandings.
Typical SLRs have native output files that are around 3000 + pixels wide and although ppi (pixels per inch) and dpi (printer dots per inch when talking about inkjets and similar) are not identical they can work as a reasonable guide.
Monitors tend to work ar 72dpi or 96dpi. Disk space and download time can be saved by having the editor save the files at that resolution. They can also be processed to best suit that resolution if screen output is the expectation.
Printers will typically default to 300dpi (Most manufacturers) or 360dpi (Epson) but will produce output from lower res files and so long as printing at a reasonable size many prints will look quite accepteable at 'normal' viewing distances for the print size at much lower resolutions.
Commercial printers will mostly use completely different types of equipment with their own ppi resolution requirements. From memory 254 ppi seems to be a coomen suggestion. I think that relates to Fuji photo printers but maybe others too.
Many editor programs can provide onscreen information about expected optimum size of output based on current output settings. So if you set an image to 3000 pixels wide at 300ppi the system will tell you that the optimum output size for that file is 10" wide. The file size is, at that point, irrelevant and depsnds as much on the level of detail in the image as it does the pixel dimensions. If you then crop the file the the optimum size is displayed. Change the ppi settings and the max width will change accordingly.
But what if you have cropped the image so that it is too small for the intended final output size no matter what resoltion is set?
Most editors will allow 'up-rez' output whereby you can export the file with size and resolution parameters set and the export will add pixels (making a larger file) to suit the settings. There are many debates about the potential for loss of quality when doing that but I suspect most recent versions of recognised quakity editors would produce a more than good enough result for all but the highest standards of fine art printers. Those with more knowledge than me please comment on that sweeping statement. Basically you are producing a digital enlargement.
I have seen articles that describe how to do this sort of enlargement in multiple steps to retain quality for ultra-large fine art prints to be produced on inklet printers or using older printer devices in a print shop but in the main the articles are about 10 years old. Things seem to have moved on rapidly in both camera sensor pixel count and printer output capability since then and I doubt that many day to day printing requirements really need complex up-rez processing these days.
That said if you sent files set at 72ppi but were asking for, say, 10x8 inch output there may well be a problem with a shortfall of data to up-rez from. The point is that is should be possible to produce the same files alrady up-rezzed to 300ppi working from the original which would be native 300pp one assumes but would be less successful creating a 300ppi file from an original offering only 72ppi (at the intended size) to start with.
I assume GC will be able to provide advice - think he has done some calenders in the past - and perhaps some other who offer commercial print services will chip in too to correct my misunderstandings.
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