# 100% crop technique



## someothername (Oct 7, 2012)

How do I use the crop tool to select a 100% detail crop from a larger image?

In other words, suppose I have a 4000x4000 pixel image and I want to make a crop that is 500x500 pixels from some part of the bigger image.  I want to post both the full size image (to Smugmug) as well as a detail portion so my viewers can see what a full size print will show.  I currently attempt to do this by pure guess work with the cropping tool, testing by double clicking on the image after cropping and seeing how much bigger or smaller it gets.   

I apologize for cross posting this also in the manage area.  I initially thought of this problem as related to exporting rather than developing.


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## clee01l (Oct 7, 2012)

It would have been much better to have kept the issue to one  topic thread.  Now that I understand your issue, I can make an appropriate recommendation. 
In LR you create a virtual copy and export the master and the virtual copy to SmugMug or where ever you desire.  After you have completed the post processing to make your image Perfect, you create a Virtual Copy of it.  Then you crop the virtual copy however your like and send both image versions to your export process.  You may need to fiddle with the export naming convention so that the master and the virtual copy get exported with unique names, but this might not matter if it is Smugmug and the destination on SmugMug generates unique names on the server.


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## Replytoken (Oct 8, 2012)

someothername said:


> How do I use the crop tool to select a 100% detail crop from a larger image?
> 
> In other words, suppose I have a 4000x4000 pixel image and I want to make a crop that is 500x500 pixels from some part of the bigger image.  I want to post both the full size image (to Smugmug) as well as a detail portion so my viewers can see what a full size print will show.  I currently attempt to do this by pure guess work with the cropping tool, testing by double clicking on the image after cropping and seeing how much bigger or smaller it gets.



Brandon,

This is one of those actions that I actually do outside of LR with FastStone.  I export the full final image from LR to my desktop.  From there, I can use FastStone to make an exact crop.  I do not know why Adobe has never seen fit to allow people to easily do this type of action, but I gave up a while ago and just use FastStone.  It's a great program for "quick and dirty" work.

--Ken


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## someothername (Oct 9, 2012)

Replytoken said:


> Brandon,  This is one of those actions that I actually do outside of LR with FastStone.  I export the full final image from LR to my desktop.  From there, I can use FastStone to make an exact crop.  I do not know why Adobe has never seen fit to allow people to easily do this type of action, but I gave up a while ago and just use FastStone.  It's a great program for "quick and dirty" work.  --Ken


  That's great to hear, since I use FastStone for quick looking.  i hadn't explored it's cropping actions, but I will look into it.  Unfortunately that's going to require my exporting to my local hard drive so FastStone can see the image with any modificationd i might have made.  I normally go direct to smugmug from LR, nicely avoiding cluttering my hard drive with large export files.  I'm exploring Fine Art America, which provides a 100% preview window from your uploaded image.


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## clee01l (Oct 9, 2012)

If you want precise, the instructions that I gave in the other thread can be applied.  If for example the Precise crop that you want is 1920X1080 pixels, you can work in full screen mode.  Sooner or later you will get lucky and the stars will align and you end up with exactly 1920X1080 pixel crop.  Now save this photo as a VC an store the VC in a collection that you can reference from time to time.  The next time you need a 1920X1080 crop, call up this image from the Collection and copy JUST the crop Settings.  Switch to the image that you want to crop and paste these settings.  You now have an exact 1920X1080 crop.  Drag it to the best composition and when you export this image to Smugmug, it will be exported as this crop along with your other develop adjustments.

My Collection contains several images that express a precise crop in pixels.  I  use these when just resizing the Aspect ration to the exported pixel size is not adequate.


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## someothername (Nov 16, 2012)

As Cletus says, once in a while you can get it right.  

The reason I wanted the 100% view was to be able to show details.   As it turns out, Fine Art American provides a 100% viewer, perfect for what I wanted.
http://fineartamerica.com/featured/lone-tree-in-pasture-brandon-smith.html

Unfortunately, no LR to Fine Art America tool, and in general I prefer smugmug.


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## Allan Olesen (Nov 17, 2012)

Rob Cole has written a Lightroom plugin called XMP Crop. It adds 2 tools which in my opinion ought to be native in Lightroom:
Crop to a specific pixel size
Change crop aspect ratio while trying to maintain crop centre and crop area.

http://www.robcole.com/Rob/ProductsAndServices/XmpCropLrPlugin/

Unfortunately it will calculate the crop incorrect if the crop angle is different from zero. But hopefully this will be solved - I have sent him the calculation methods for an image with a crop angle.

Also, it will not work on virtual copies, so you will need to crop before you create the virtual copy, and then remove the crop on the original. This is because the only way of controlling a crop in Lightroom without using the UI is creating an XMP sidecar file and modifying it, and virtual copies do not have XMP sidecars.


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## clee01l (Nov 17, 2012)

Allan Olesen said:


> Rob Cole has written a Lightroom plugin called XMP Crop...
> Also, it will not work on virtual copies, so you will need to crop before you create the virtual copy, and then remove the crop on the original. This is because the only way of controlling a crop in Lightroom without using the UI is creating an XMP sidecar file and modifying it, and virtual copies do not have XMP sidecars.


It probably does not work on DNGs and JPEGs either since they do on have XMP sidecars files.  Rob Cole is notorious for developing half baked solutions.


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## Victoria Bampton (Nov 17, 2012)

XMP's still written to the headers of DNGs and JPEGs, so guessing at what he's done there, it probably will work for those formats.


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## Allan Olesen (Nov 18, 2012)

clee01l said:


> It probably does not work on DNGs and JPEGs either since they do on have XMP sidecars files.


I was only writing about sidecars because raw is what I use, and sidecars is the way to do it with a raw, even if you could do it directly in the raw file. 

For JPG you can change the same metadata in the JPG file and get the crop. For DNG I don't know and don't really want to know - but I would be surprised if it didn't work.

If you don't want to use Rob Cole's tool, you can do it yourself with exiftool. That is what I do since Rob Cole's tool as earlier mentioned doesn't make the correct crop for photos with a crop angle.

If you have a 6000x4000 photo, this command will crop it to 600x600 pixels, starting at the upper left corner:
exiftool -xmp-crs:CropTop="0.0" -xmp-crs:CropLeft="0.0" -xmp-crs:CropBottom="0.15" -xmp-crs:CropRight="0.1" <filename>

After running the command, you will need to do a "Read from metadata" in Lightroom.

The 4 parameters in the command are coordinate values in a system where 0,0 is upper left corner and 1,1 is bottom right corner in the original photo (before any rotation of portrait images took place in Lightroom). So you have to calculate the wanted height and width as proportions of the full height and width of the original photo:

Height:
CropBottom = 600 pixels / 4000 pixels = 0.15.

Width:
CropRight = 600 pixels / 6000 pixels = 0.1.

One warning: You will have to wait until you have imported the JPG into  Lightroom. It doesn't work if you change metadata first and then import  to Lightroom.

Another warning: If you plan to adjust the crop angle, you should apply the crop first. Otherwise you will get the wrong height and width of the crop area.


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## Roscoe17 (Dec 2, 2012)

someothername said:


> How do I use the crop tool to select a 100% detail crop from a larger image?
> 
> In other words, suppose I have a 4000x4000 pixel image and I want to make a crop that is 500x500 pixels from some part of the bigger image.  I want to post both the full size image (to Smugmug) as well as a detail portion so my viewers can see what a full size print will show.  I currently attempt to do this by pure guess work with the cropping tool, testing by double clicking on the image after cropping and seeing how much bigger or smaller it gets.



That's kinda funny.  I push a lot of my pictures to my iPad and want them to have an exact 2048 pixels on one side.  Normally I simply rely on LR export resizing but sometimes my desired crop is so close to 2048 that I'd rather do it myself than have a minor resize occur (which can degrade image quality)...and LR can't without following Cletus' procedure.  I asked this same question on another forum (Nikon-specific) and was basically ridiculed for wanting to do such a thing.  Personally, I find it amazing that such an option doesnt exist in LR but...


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## Andy Civil (Oct 24, 2014)

I've found a trick to making a crop a specific size, and I've posted a youtube video describing it. It's not too different from what Cletus D Lee suggested, except that I find that you can't adjust the crop pixel by pixel, it might go say, three at a time, so you may never land on the exact number you want. (If you invoke 'crop', it cancels 1:1 view.) Please check it out.
https://www.youtube.com/watch?v=4wsoSeuF_4I


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