Posted by Danny Laureys on November 2, 2012 at 7:22 PM
Hi,
I'm confused as how to resize in photoshop cs4 for larger prints. I shoot raw with a D52,convert the files to DNG. Once ARC they are all at 300 - 16 bit. when x-fered to photoshop they are usually around 13 x 9 sometimes a bit bigger or smaller. but let say I want a larger print like 11 x 14, 19 x 13, 24 x 16,or larger how do I go by doing this without loosing sharpness? I know I have to do all my resizing in the image size window box. Do I leave the "resample image box" checked or unchecked.And which Bubic setting do I use for enlargments. I have no problem resizing for the web.I hope I explained this right. These are all TIFF,RGB @ 300 Resolution files. Do I crop them to the right size before I resize them?.Thank you for your time.
Posted by John Clulow on November 3, 2012 at 10:31 AM
Hi Danny,
I can share my personal experience, for what it's worth. There are programs you can purchase for this purpose. I downloaded "the best one", which shall remain nameless, on a 30 day trial and did a controlled comparison using that program with the method I am about to describe, and I found no significant difference in the results.
I have made many nice 20 X 30" prints using the following process:
Selecting Image>Image Size
Use the highest resolution image you have available (based upon pixels in the top window ),
Set resolution at 300 dpi
Select Constrain Proportions, and Bicubic Smoother (Best for Enlargement)
Change the top window parameter from pixels to percentage
Change the numbers to 110 (110% enlargement)
Click OK to execute this increment of enlargement.
Repeat all of the above steps until the pixel size of your image is equivalent to print the image size you want.
For example, for a 20 X 30 inch print at Costco, you will need a 6000 X 9000 image (assuming 300 dpi). From my K-5 which is a 16.1 MP sensor, this takes from seven to eight iterations of the above process.
Some will say you can just do it in one step. My tests show marginal improvement by using 10% enlargement steps, and if you don't mind spending the time, it couldn't hurt. Maybe one step enlargement gives equivalent results, but I do it the way I've described because I have more time than money.
One thing I do know is that the result of the interpolation algorithms in photoshop bicubic is indistinguishable (by my pixel peeking evaluation) from the commercial software which costs around $100 to buy.
Worth a try :)
Posted by David Bostedo on November 4, 2012 at 12:38 AM
Danny - A few notes on resizing for printing...
-- You want your image file to be set to the size print you want and have a good ppi number - typically larger than about 180.
-- If you know what our particular printer or print service recommends, use that.
-- Epson printers work well at 360 ppi, Canon at 300 ppi. (Those are their "native" resolutions.)
-- Printer drivers have gotten really good at resizing though, so as long as your at least at 180 or more, you may get results you like without doing the resizing yourself, and let the printer driver do it.
Now with respect to the "Image Size" dialog in Photoshop, if you do want to resize, here's what I'd do (there are some other way to do this) :
-- Open the Image Size dialog
-- Make sure "Resample Image" is selected. This will change the number of pixels to match the size and ppi you select.
-- Set the Width OR Height to be what you want for your print; The other number will change automatically, assuming you have "Constrain Proportions" selected.
-- Set the resolution line to be the ppi you want
-- Select "Bicubic Smoother" as it does somewhat better with enlargements
-- Hit "OK"
This will give you an image with the size and resolution you want for printing. Note that the sizes you mentioned are not all the same aspect ratio, so you can't just resize to get them. I would do the resize to get the shorter dimesion to be what I wanted, and then do a crop to the final size. For instance, if I have an image that is 4000 x 6000 pixels, and I want a 16x20 image, I can't just resize. I would set it to be 16x24, then crop it back down to 16x20.
Now you asked about sharpening... Sharpening for printing is important to get the absolute best results. Just doing a resize will likely always affect sharpness to some extent. So you should resharpen after doing any resizing. Now how much to sharpen for a print is a little bit of guesswork - the best results may look a bit over-sharpened on screen. It may take some trial and error to figure out what's best.
Posted by Danny Laureys on November 5, 2012 at 6:48 PM
Thanks for all the info.
Posted by David Taylor on November 13, 2012 at 12:24 AM
A quick followup to John Clulow's recommendation of enlarging by 110% (consecutively enlargements). This is a good reason to upgrade to PhotoShop CS6, because (I believe, starting around CS5) Adobe built this functionality into the enlargement process. It does this incremental enlargement behind the scenes now, and in CS6, you no longer need to choose which Bicubic method you would like to use. CS6 analyzes your image and the numbers you put in for the new size, then chooses the best algorithm for the task.
David Bostedo is exactly right, ANY time you change your image size (or resolution) within PS, you are losing sharpness and will need to do post resizing sharpening. I (typically) wait until the very end of my workflow to run my sharpening actions, after I've resized for the correct usage. Before I sharpen though, I highly recommend saving your 'Master File' (all the layers and adjustments) BEFORE flattening. This way, you can always reopen your master file, resize for whatever need you have & then sharpen for that particular use. For printing purposes (on our Epson Stylus Pro 9900 and most inkjet printers) we recommend slightly over-sharpening - you actually want to create a subtle 'halo' - in order to get the highest print quality. The halo will not be apparent in the final print, but the sharpness will be.
Posted by David Bostedo on November 13, 2012 at 7:22 PM
This is a good reason to upgrade to PhotoShop CS6, because (I believe, starting around CS5) Adobe built this functionality into the enlargement process.
I agree with David T's suggestion to use a 'Master file'-targeted' workflow. My master files are never flattened or sharpened. I simply duplicate my master file, save it under a new name and prepare the duplicate file for printing.
Regarding sharpening for print: It has been my experience that if the image looks a little 'crunchy' (slightly over-sharpened) on the screen, the resulting print looks very nice. Also, on some papers, you may need to boost contrast just a bit. Proof prints are a great way to see if you're in the ball park.
Discussion
7 repliesI'm confused as how to resize in photoshop cs4 for larger prints. I shoot raw with a D52,convert the files to DNG. Once ARC they are all at 300 - 16 bit. when x-fered to photoshop they are usually around 13 x 9 sometimes a bit bigger or smaller. but let say I want a larger print like 11 x 14, 19 x 13, 24 x 16,or larger how do I go by doing this without loosing sharpness? I know I have to do all my resizing in the image size window box. Do I leave the "resample image box" checked or unchecked.And which Bubic setting do I use for enlargments. I have no problem resizing for the web.I hope I explained this right. These are all TIFF,RGB @ 300 Resolution files. Do I crop them to the right size before I resize them?.Thank you for your time.
I can share my personal experience, for what it's worth. There are programs you can purchase for this purpose. I downloaded "the best one", which shall remain nameless, on a 30 day trial and did a controlled comparison using that program with the method I am about to describe, and I found no significant difference in the results.
I have made many nice 20 X 30" prints using the following process:
Selecting Image>Image Size
Use the highest resolution image you have available (based upon pixels in the top window ),
Set resolution at 300 dpi
Select Constrain Proportions, and Bicubic Smoother (Best for Enlargement)
Change the top window parameter from pixels to percentage
Change the numbers to 110 (110% enlargement)
Click OK to execute this increment of enlargement.
Repeat all of the above steps until the pixel size of your image is equivalent to print the image size you want.
For example, for a 20 X 30 inch print at Costco, you will need a 6000 X 9000 image (assuming 300 dpi). From my K-5 which is a 16.1 MP sensor, this takes from seven to eight iterations of the above process.
Some will say you can just do it in one step. My tests show marginal improvement by using 10% enlargement steps, and if you don't mind spending the time, it couldn't hurt. Maybe one step enlargement gives equivalent results, but I do it the way I've described because I have more time than money.
One thing I do know is that the result of the interpolation algorithms in photoshop bicubic is indistinguishable (by my pixel peeking evaluation) from the commercial software which costs around $100 to buy.
Worth a try :)
-- You want your image file to be set to the size print you want and have a good ppi number - typically larger than about 180.
-- If you know what our particular printer or print service recommends, use that.
-- Epson printers work well at 360 ppi, Canon at 300 ppi. (Those are their "native" resolutions.)
-- Printer drivers have gotten really good at resizing though, so as long as your at least at 180 or more, you may get results you like without doing the resizing yourself, and let the printer driver do it.
Now with respect to the "Image Size" dialog in Photoshop, if you do want to resize, here's what I'd do (there are some other way to do this) :
-- Open the Image Size dialog
-- Make sure "Resample Image" is selected. This will change the number of pixels to match the size and ppi you select.
-- Set the Width OR Height to be what you want for your print; The other number will change automatically, assuming you have "Constrain Proportions" selected.
-- Set the resolution line to be the ppi you want
-- Select "Bicubic Smoother" as it does somewhat better with enlargements
-- Hit "OK"
This will give you an image with the size and resolution you want for printing. Note that the sizes you mentioned are not all the same aspect ratio, so you can't just resize to get them. I would do the resize to get the shorter dimesion to be what I wanted, and then do a crop to the final size. For instance, if I have an image that is 4000 x 6000 pixels, and I want a 16x20 image, I can't just resize. I would set it to be 16x24, then crop it back down to 16x20.
Now you asked about sharpening... Sharpening for printing is important to get the absolute best results. Just doing a resize will likely always affect sharpness to some extent. So you should resharpen after doing any resizing. Now how much to sharpen for a print is a little bit of guesswork - the best results may look a bit over-sharpened on screen. It may take some trial and error to figure out what's best.
David Bostedo is exactly right, ANY time you change your image size (or resolution) within PS, you are losing sharpness and will need to do post resizing sharpening. I (typically) wait until the very end of my workflow to run my sharpening actions, after I've resized for the correct usage. Before I sharpen though, I highly recommend saving your 'Master File' (all the layers and adjustments) BEFORE flattening. This way, you can always reopen your master file, resize for whatever need you have & then sharpen for that particular use. For printing purposes (on our Epson Stylus Pro 9900 and most inkjet printers) we recommend slightly over-sharpening - you actually want to create a subtle 'halo' - in order to get the highest print quality. The halo will not be apparent in the final print, but the sharpness will be.
I believe that actually started in CS3.
Regarding sharpening for print: It has been my experience that if the image looks a little 'crunchy' (slightly over-sharpened) on the screen, the resulting print looks very nice. Also, on some papers, you may need to boost contrast just a bit. Proof prints are a great way to see if you're in the ball park.
--P