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03/27/2017 09:23:10 AM · #1
The native resolution of my camera is 5184px x 3456px.

After straightening, I am forced to crop but I hate losing pixels.
In the past, I have guessed and inserted the following into the photoshop boxes:

5100px x 3400px @ 300 dpi that produces a 17" x 11.33" print.

I want to keep the same 3:2 aspect ratio but do not want interpolation of pixels to occur.
Furthermore, I do not want to lose any unnecessary pixels.

When I am forced to crop after straightening what is the most effective way NOT to lose pixels.
What numbers do I insert into the photoshop boxes?

Any help would be kindly appreciated.
03/27/2017 09:54:25 AM · #2
The first step is to crop as minimally as possible, using Ps's option to constrain the aspect ratio to the desired value. Once this is done, really you need to do nothing else. If, however, you want the printed size to be a particular value, then open the Image>Resize dialog, un-check the Resample box and set either the length or width dimension to your desired dimension. You will notice the DPI changes to reflect your choice. That's all there is to it.
03/27/2017 10:00:56 AM · #3
Originally posted by kirbic:

The first step is to crop as minimally as possible, using Ps's option to constrain the aspect ratio to the desired value.


Kindly explain this step in more detail. I don't quite understand.

03/27/2017 10:18:49 AM · #4
Originally posted by kirbic:

The first step is to crop as minimally as possible.


Before I take that first step, photoshop requests numbers.
I do not know what those numbers are supposed to be.

5100px x 3400px
5121px x 3414px
5130px x 3420px

How do I find out what those numbers are supposed to be?

03/27/2017 10:42:38 AM · #5
cropping.png?w=665

Here I guessed the W and the H and inserted:

5100px x 3400px

The dimensions in pixels are actually less than that but I do not know what those dimensions are.

Before I select the crop tool, is there a way that I could select the area to be cropped to find out the dimensions in pixels?



Message edited by author 2017-03-27 11:14:57.
03/27/2017 12:46:03 PM · #6
Don't put in ANY numbers when you crop, that way it does not resample (either add or discard pixels) as part of the copping process. You can then adjust the size afterward when you know how many pixels you have after cropping. Unless the image ends up at less than 150dpi at your desired print size you don't need to do anything else.
03/27/2017 01:22:57 PM · #7
Ach, the damn Ps Crop tool. Frankly, I never use it. Here's the process I use:
1.) Straighten:
- Select the ruler tool
- Drag along a horizontal or vertical line
- Select Image>Rotate>Arbitrary; the angle of the ruler will already be there as the default
- Complete the rotation
2.) Crop
- Select the rectangular marquee tool
- Set the tool for the specific aspect ratio I want using the toolbar settings
- Drag to select the area to retain
- Image>Crop
3.) Done, unless you want a specific physical print size, then:
- Image>Resize
- Uncheck resample box
- Set one dimension (Height or Width) the other should follow automatically because you used the correct aspect ratio above
03/27/2017 02:29:00 PM · #8
Originally posted by kirbic:

Ach, the damn Ps Crop tool. Frankly, I never use it.

The "old one" (i.e PS 5.0 using the Info Window with "options") is straightforward and easy to use, with the CS versions using the "toolbar" at the top it's a real PITA ...

If you check the "Fixed Size" option you can crop and resample in one step (choice of units available) Copyrighted_Image_Reuse_Prohibited_1197520.jpg

If you UNcheck the "Fixed Size" option the Info window will show you the dimensions of the cropped image (in pixels in this case) Copyrighted_Image_Reuse_Prohibited_1197521.jpg
03/27/2017 09:43:16 PM · #9
Thanks Paul, I have elements and don't have those options.

Originally posted by kirbic:

Crop
- Select the rectangular marquee tool
- Set the tool for the specific aspect ratio I want using the toolbar settings
- Drag to select the area to retain
- Image>Crop

Thanks Fritz, this is the method that I will use from now on.

The only problem is that you only get one go with the rectangular marquee tool.
Once you have chosen your rectangle and it becomes displayed, you cannot fine tune it. It seems that you have to get it right the first time.

I tried grabbing a corner to make it a touch bigger, but it just moved the whole rectangle.
03/27/2017 09:59:07 PM · #10
Originally posted by johnbrennan:

...I tried grabbing a corner to make it a touch bigger, but it just moved the whole rectangle.


That be true, it is the one downside to the method. I truly wish that the crop tool in Ps worked the same way that it does in Lr - that is the way it *should* work.
03/27/2017 10:05:49 PM · #11
Originally posted by GeneralE:

Don't put in ANY numbers when you crop.

I am able to select No Restriction in PS Elements.
It allows me to do as you suggested and not put any numbers in the boxes.

The end result is that I do not lose any pixels, which is really good, but the aspect ratio is not exactly correct.

Do I then go into Image Resize to correct it?
03/27/2017 11:09:24 PM · #12
Originally posted by johnbrennan:

Originally posted by GeneralE:

Don't put in ANY numbers when you crop.

I am able to select No Restriction in PS Elements.
It allows me to do as you suggested and not put any numbers in the boxes.

The end result is that I do not lose any pixels, which is really good, but the aspect ratio is not exactly correct.

Do I then go into Image Resize to correct it?

No, if the aspect ratio is off you have to crop (or distort), or make it smaller than the print size (in the longest dimension) and add a border.

If one dimension is the correct size and the other is too big, then use "Canvas Size" (not the crop tool) to trim off the excess.
03/28/2017 07:14:21 AM · #13
Originally posted by GeneralE:

Unless the image ends up at less than 150dpi at your desired print size

I'm working on an image now where the image is less than 150dpi.

The internal dimensions of the matt is 96cm x 35 cm.
I inserted those figures into the crop tool boxes but
I DID NOT insert a figure in the ppi box.
I left it. blank

When I looked at the credentials of the (96 x 35) image the ppi was less than 150dpi.

What is my next step?
Is this where interpolation comes into play?
03/28/2017 02:46:19 PM · #14
Originally posted by johnbrennan:


I'm working on an image now where the image is less than 150dpi.

The internal dimensions of the matt is 96cm x 35 cm.
I inserted those figures into the crop tool boxes but
I DID NOT insert a figure in the ppi box.
I left it. blank

When I looked at the credentials of the (96 x 35) image the ppi was less than 150dpi.

What is my next step?
Is this where interpolation comes into play?


Given your final image dimensions, you'd need about 5670 px in the long dimension to achieve 150dpi. If you're even close to that, I'd go ahead and print at your native dimensions. The printer will scale appropriately for their output resolution. The 150 number is a target, but the required dpi to avoid visible pixelation is dependent on the vieweing distance, and for a print nearly a meter wide, that viewing distance is obviously not meant to be close-up.
03/29/2017 12:44:54 AM · #15
Originally posted by kirbic:

Given your final image dimensions, you'd need about 5670 px in the long dimension to achieve 150dpi. If you're even close to that, I'd go ahead and print at your native dimensions. The printer will scale appropriately for their output resolution. The 150 number is a target, but the required dpi to avoid visible pixelation is dependent on the viewing distance, and for a print nearly a meter wide, that viewing distance is obviously not meant to be close-up.

When I looked at my image credentials this is what I saw:

96cm x 35cm @93dpi

So normally, would I upscale in photoshop or see how it prints as is?

I had to do another straighten which meant another crop so I inserted

96cm x 35cm @150dpi

The end result is that it must have upscaled. It provided me with 5670px in the long dimension.
I guess the print will turn out OK.

I don't know why I have such a problem with understanding the pixel dilemma.
I understand the mathematics perfectly, but just get so lost in photoshop when it comes to cropping.
I have taken on board what both Paul and you say and may use the rectangular marquee tool from now on.

Paul's idea is also good where he crops as little as possible not set to a particular aspect ratio, then changes the canvas size to suit. I have not tried that method yet.

Message edited by author 2017-03-29 04:21:45.
03/29/2017 11:51:19 AM · #16
Originally posted by johnbrennan:

...When I looked at my image credentials this is what I saw:

96cm x 35cm @93dpi

So normally, would I upscale in photoshop or see how it prints as is?


Yes, that's what I would do. I would confirm with the print house that they will scale to their native print resolution prior to printing, and if not I would scale to that resolution prior to sending. They should scale it properly.

Originally posted by johnbrennan:

I had to do another straighten which meant another crop so I inserted

96cm x 35cm @150dpi

The end result is that it must have upscaled. It provided me with 5670px in the long dimension.
I guess the print will turn out OK.


Yes, it upscaled. The "resample" box was certainly checked. That's the default condition.

Originally posted by johnbrennan:

I don't know why I have such a problem with understanding the pixel dilemma.
I understand the mathematics perfectly, but just get so lost in photoshop when it comes to cropping.
I have taken on board what both Paul and you say and may use the rectangular marquee tool from now on.

Paul's idea is also good where he crops as little as possible not set to a particular aspect ratio, then changes the canvas size to suit. I have not tried that method yet.


Paul's methodology is great where you are adding a border; the difference in the aspect ratio, if small, can be made up with a slightly non-uniform border.
03/29/2017 11:47:54 PM · #17
I should have read this post earlier. It was on another topic last year.
Originally posted by kirbic:

I have definitely screwed myself on the size reduction before. Here's how I put that demon to rest for good. I trained myself to *never* resize my PSD. I save a JPEG copy, open that and do my resizing. If I need to go back and do additional edits, I always have that full size PSD. Now granted, I may be beyond my 20-step history, but my M.O. is also to do as much of my editing non-destructively as possible. That way I limit the amount of work I need to do on a re-edit. I do still occasionally fall into the trap of "just a quick destructive edit" and then realize it is more involved than I thought. Each time I do this, it reinforces the attitude to do the right steps, that is non-destructive flow, even if it takes a little more time initially

Originally posted by johnbrennan:

...When I looked at my image credentials this is what I saw:

96cm x 35cm @93dpi

I had to do another straighten which meant another crop so I inserted

96cm x 35cm @150dpi


Originally posted by kirbic:

Yes, it upscaled. The "resample" box was certainly checked. That's the default condition.


Because 300dpi is better than 150dpi, should I have inserted 300dpi?

Should I have inserted:
96cm x 35 cm @300dpi

OR is that pushing the envelope?

And just one more thing, what file type to I give to the printer?

What file type do I "Save As"?

Message edited by author 2017-03-30 00:39:21.
03/30/2017 01:59:08 PM · #18
Originally posted by johnbrennan:

Because 300dpi is better than 150dpi, should I have inserted 300dpi?

Should I have inserted:
96cm x 35 cm @300dpi

OR is that pushing the envelope?


It's of course going to increase the file size dramatically, and it won't give you any more detail. Best to let the print house handle this, again assuming that they will scale up to their printer resolution.

Originally posted by johnbrennan:

And just one more thing, what file type to I give to the printer?

What file type do I "Save As"?


Give them what they ask for. Most print houses will deal with whatever you give them, but it is best to give ti to them in the format they prefer. One thing though... if you're already in JPEG format, there is no use converting it back to TIF if that is their preferred format. You've already taken the hit on compression and reduction to 8 bit color depth.
03/31/2017 12:04:07 AM · #19
Originally posted by kirbic:

One thing though... if you're already in JPEG format, there is no use converting it back to TIF if that is their preferred format. You've already taken the hit on compression and reduction to 8 bit color depth.

I shoot in JPEG not RAW.
From my camera, I import images that are displayed as JPEG using Irfanview.

Then I open them in photoshop and it produces a PSD.

At this point have I taken the hit on compression and reduction to 8 bit color depth?
03/31/2017 07:32:11 AM · #20
Originally posted by johnbrennan:



At this point have I taken the hit on compression and reduction to 8 bit color depth?


Then send JPEG. No benefit to sending another format.
JPEG format has 8 bits of color depth per channel; each color channel has 256 levels. Your camera natively has at least 14 bits per channel, or 16,384 levels. Color gradients are a lot smoother at the higher bit depth.
03/31/2017 10:34:44 AM · #21
Originally posted by kirbic:

Originally posted by johnbrennan:



At this point have I taken the hit on compression and reduction to 8 bit color depth?


Then send JPEG. No benefit to sending another format.
JPEG format has 8 bits of color depth per channel; each color channel has 256 levels. Your camera natively has at least 14 bits per channel, or 16,384 levels. Color gradients are a lot smoother at the higher bit depth.

While it is true that shooting in JPEG (I do too) limits the quality of the initial data, saving in JPEG after editing introduces a (possible) second level of compression/data loss, though I understand that if you save at the highest quality level JPEG from new versions of Photoshop it uses "lossless" compression. A TIFF file saved with the LZW compression algorithm is also lossless (all the data is restored when re-opening the file), but not all print houses accept that format.
04/01/2017 11:14:49 AM · #22
Originally posted by GeneralE:

While it is true that shooting in JPEG (I do too) limits the quality of the initial data, saving in JPEG after editing introduces a (possible) second level of compression/data loss, though I understand that if you save at the highest quality level JPEG from new versions of Photoshop it uses "lossless" compression. A TIFF file saved with the LZW compression algorithm is also lossless (all the data is restored when re-opening the file), but not all print houses accept that format.


So f I shoot in JPEG, what is the best mode of attack?

Native Camera > JPEG > Import File Type > PSD?
04/01/2017 11:27:55 AM · #23
I initially save to and edit in PSD format. When I'm done making adjustments, I save as a full-sized TIFF. I then do any cropping, resizing, and sharpening to the TIFF ("finishing"), and then save the result as either TIFF or JPEG, depending on the requirements of the final use.

For a DPC entry I will typically have Original, PSD, TIFF, Resized TIFF, Resized/sharpened TIFF, JPEG. I save the two (smaller) TIFFs so I can go back and re-sharpen if the first version is unsatisfactory, and I can try saving with various JPEG compression levels (I don't use a "SaveForWeb" feature).

It makes more files, but mine are relatively small and storage has gotten ridiculously large, so I try to not throw anything out unless really necessary ...
04/01/2017 10:46:55 PM · #24
Originally posted by GeneralE:

I initially save to and edit in PSD format. When I'm done making adjustments, I save as a full-sized TIFF. I then do any cropping, resizing, and sharpening to the TIFF ("finishing"), and then save the result as either TIFF or JPEG, depending on the requirements of the final use.

For a DPC entry I will typically have Original, PSD, TIFF, Resized TIFF, Resized/sharpened TIFF, JPEG. I save the two (smaller) TIFFs so I can go back and re-sharpen if the first version is unsatisfactory, and I can try saving with various JPEG compression levels (I don't use a "SaveForWeb" feature).

It makes more files, but mine are relatively small and storage has gotten ridiculously large, so I try to not throw anything out unless really necessary ...


I found all of this extremely useful.

When you first import from camera [JPEG] to device, do you import and display as PSD?
04/01/2017 11:00:19 PM · #25
I don't "import" -- I use a card reader and just drag the files from the card to the hard drive (on either Windows or Mac). But yes, when I open it in Photoshop, I save it as a PSD file before doing any editing. Very rarely for a Minimal editing challenge I will use a program like IrfanView to open, resize, and save the entry directly to another JPEG.

However, if I want to print it I will use my usual workflow, but taking the adjusted/edited full-sized TIFF back into Photoshop to crop or border to a standard size, as we've been discussing (thus adding at least three more files to the collection).
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