Photoshop
Tutorial
Tutorial #2
Resizing an image for Alamy
Important update: As of May 2010 Alamy have REDUCED the required uncompressed file size to 24MB
The screenshots below are based on the previous requirement for an uncompressed file size of 48MB. The red box below the applicable screenshot gives the amended figures. Many cameras will take images of the required size without any alteration.
Judging by the many, many repeat questions on the Alamy stock site forums it seems that there is a good deal of confusion about what they actually require and how to achieve it.
A quick look on Alamy's website shows that they are quite specific about what you should submit:
1. File type: JPEG’s saved at a high quality setting (i.e. Photoshop level 10 or above)
2. File Name: Alpha-numeric file names ending in .jpg
3. Colour: RGB files, not single channel greyscale or CMYK
4. File size: Uncompressed file sizes of between 24 and 200 MB. This means you should make your
JPEG file from an 8 bit TIFF file that is at least 48MB. Our maximum file size for the uncompressed
file is 200MB
So what is the problem? Well judging by the many questions, the problem is mainly about requirement number 4 and usually goes along the lines of “…but my original JPEG image is only 2MB at the moment so how can I make it 24MB and won’t it then be HUGE…?”
So let’s look at all 4 requirements one-by-one – but it actually makes more sense if we look at them in reverse order:This is the one that causes so much confusion – and it all stems from the word ‘uncompressed’. JPEG’s are relatively small files compared to RAW and TIFF files and they achieve this small size by compressing the data. If the data was uncompressed then the file size would be much larger – and it is this uncompressed file size that Alamy is stipulating not the actual size of the compressed JPEG file.
An uncompressed 24MB image is actually only about 5 MB – but even this is probably bigger than your digital camera produces. Therefore you still need to make that image bigger.
Here’s how to do it:
Open the file in Photoshop.
Go to ‘Image’ -> ‘Mode’ and tick next to 16-Bits/Channel (if it is not already)
Save the file as either a PSD or TIFF file (depending on your preference). The reason for this is that a 16- bit/channel file will retain all of the colour changes that you may carry out as you prepare the image, whereas an 8-bit/channel file may lose some of the data.
Prepare your image to satisfy Alamy’s exacting standards (read their criteria on their website to find out EXACTLY what they won’t accept).
When you think that you have prepared enough, zoom in to 100% and check every square inch of the image for defects. Rectify every single minute defect otherwise your images will be rejected.
Select Image -> Image Size
If necessary, change the pixel dimensions of the LONGEST SIDE of the image to at least 3600. Leave the other shorter dimension alone - but make sure that ‘constrain proportions’ is checked so that this shorter dimension increases automatically to keep the image in the same proportion as the original.
Check the box ‘Resample Image’ and change the drop-down box to ‘Bicubic Smoother’.
Press OK
Screenshot amendment: Change the dimension of the longest side to at least 3600
If you look at the lower left-hand side of your image you should see the new file size which will now be around 50MB.
Screenshot amendment: File size should now be about 50 MB Go to Image -> Mode and tick next to 8-Bits/Channel
You should now see that the file size has reduced to about the 24MB file size you are after.
Screenshot amendment: Now that the image mode is 8 bits/channel the file size will reduce to about 24 MB
Note: Your camera’s original image size may be slightly different so you may have to adjust the 3600 figure above to optimise the resultant file size - but always make sure that it stays above the magical 24MB.
Go to Image -> Mode and tick next to RGB colour (if it is not already).
You are now ready to save your image and the saved JPEG should be named with only letters and numbers.
(Since you are saving it as a JPEG then the suffix should automatically be ‘.jpg’).
Click ‘save as’ and change the format to JPEG.
When you click OK the ‘JPEG Options’ box will appear and you need to change the quality level to 10 or above. Press OK.
It may take a little time for your PC to convert and compress this large file but when is has, if you hover over the file in Windows Explorer you will see that the actual size of the JPEG is only about 5MB. This is the file that you can upload to Alamy.
Good luck !!
In the next tutorial we will create a contact form for a web page.
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