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Matt Kynaston

Convert Raw to JPEG without shrinking the file

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39 minutes ago, MDM said:

 

I  can never understand why this size thing is problematic for experienced photographers. In Photoshop the pixel dimensions are clearly displayed in MB in the Image SIze dialog box as well as the Info panel. Lightroom gives the size in MP so if it is showing 6MP then it is over the 17MB limit with a simple x3 multiplication. I know the x3 isn't exact bit it should be sufficient in the vast majority of cases.

 

I can understand of course why novices don't understand the relationship between pixel dimensions and file size on disk but surely that indicates that they have a bit of background work to do to bring their knowledge up to scratch. This has to be the No 1 FAQ on here and it never goes away. 

 

I don't understand why it's so problematic either. Perhaps Alamy just need to say that the image needs to have at least 6,000,000 pixels and forget about the confusing 17MB requirement. There again, it may not stop this still being the number 1 FAQ!

 

There is no fixed relationship between image size in pixels and file size on disk for a JPEG, so anybody looking at the file size of an image they are about to submit is going to be little wiser about whether the image is big enough. On the other hand (in Windows) look at Properties -> Dimensions and it will tell you what you need to know. 

 

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2 hours ago, Harry Harrison said:

Well that sounds OK, the information with the last update in February 2015 said the following, which was clearly based on earlier Alamy standards:

 

Colour codes Size - Red for less than 24MB (Fail), Blue for 24 to 48MB, Green for 48MB and above.

 

I can see that it can be useful and I should probably spend more time looking at it before commenting, it's very quick and you can sort on the uncompressed size column.

 

Definitely an old version - I'm running 1.1.7 which only goes red below 17MB.

 

It would also be great if the author of Alamy SizeChecker could produce a version that also showed green for sRGB as there's absolutely no point in submitting AdobeRGB to Alamy because they convert to sRGB on receipt. In fact I would argue it's better to submit sRGB to Alamy so that you can check the colour rendering and histogram in sRGB colour space before submission. Does anyone know how to contact him? (The contact link on his website no longer works - he's retired).

 

Mark

Edited by M.Chapman

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49 minutes ago, LawrensonPhoto said:

I was just trying to simplify it with a minimum 3000 px , it doesn't seem to be getting through though

But you can't simplify it with a minimum of 3000px on the long side. Some images that pass the test will (correctly) fail the Alamy criteria. And some images that fail the 3000px test would have passed the Alamy test. And we're not just talking about at the margins of a few pixels. 2450 x 2450 would pass the Alamy test. 3000 x 1500 wouldn't pass.

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50 minutes ago, LawrensonPhoto said:

I was just trying to simplify it with a minimum 3000 px , it doesn't seem to be getting through though

 

But that doesn't work for all formats. Simple rule, make sure you have more than 6 million pixels in the image.

 

Also, I sometimes make panoramic crops from 4:3 images, so going "panoramic" isn't always about increasing the number of pixels.

 

Mark

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9 minutes ago, Keith Douglas said:

I don't understand why it's so problematic either. Perhaps Alamy just need to say that the image needs to have at least 6,000,000 pixels and forget about the confusing 17MB requirement. There again, it may not stop this still being the number 1 FAQ!

 

 

But this is Alamy's entrance exam. 😀 so they leave as 17MB to confuse and exclude those that don't have the expertise.

 

Mark

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On 17/09/2019 at 18:05, Matt Kynaston said:

I am trying to upload 3 images for my first stock submission, and obviously want to stay within the guidelines.

 

11 minutes ago, M.Chapman said:

But that doesn't work for all formats.

 

Are you suggesting uploading panoramas as his first uploads?, if we keep it simple by using the min. 3000px on the longest side for STANDARD formats (3:2 4:3) he will have no issues with file sizes.

 

 

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9 hours ago, LawrensonPhoto said:

Are you suggesting uploading panoramas as his first uploads?, if we keep it simple by using the min. 3000px on the longest side for STANDARD formats (3:2 4:3) he will have no issues with file sizes.

 

No. I was merely pointing out that 6 million pixels is a simple rule that works for all formats, including 1:1, 3:2, 4:3 and panoramas, wheres 3,000 pixel long side doesn’t. I was also answering your earlier question.

 

"Panoramas = Why would you ever downsize a panoramic image when the whole point is to increase pixels!!!???"

 

Mark

 

Edited by M.Chapman
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9 hours ago, M.Chapman said:

Simple rule, make sure you have more than 6 million pixels in the image

Looks good to me, it means the threshold for uncompressed file size is in effect raised to 17.16MB but that's a small price to pay for the sake of simple maths!

 

Incidentally I'm not sure if Alamy actually define their 'panoramic' filter anywhere but in a cursory search I've found one image at exactly 2:1 Aspect ratio but none below that so I suspect that is the threshold.

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10 hours ago, LawrensonPhoto said:

 

 

Are you suggesting uploading panoramas as his first uploads?, if we keep it simple by using the min. 3000px on the longest side for STANDARD formats (3:2 4:3) he will have no issues with file sizes.

 

 

 

That is not simple. It is adding an extra complexity in terms of STANDARD formats. If somebody is confused by the straightforward 17MB which can be read very simply from a dialog box or panel in Photoshop or in Bridge, then what are they going to make of the idea of 3000 pixels long side as long as it is a standard format with a maximum ratio of 1.5 (3:2) which is effectively what you are saying. I can just see the explanations on here becoming an order of magnitude more complex than they are already, not to mention what the Alamy advice would entail. 

 

And how would they even work that ratio out if they can't do a simple read out in a dialog box or do a simple calculation based on the megapixel size from the Lightroom display. Presumably other software has similar. 

 

A simple bit of advice such as make sure your image is at least 6MP or 17MB in size (explain how to see this in standard imaging software) will cover everything. Yes it doesn't need to be the full 6MP but that will get them over the bar. Why they chose 17MB rather than 18MB is a bit of a mystery as that would have really simplified things.

Edited by MDM

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1 hour ago, MDM said:

 

That is not simple. It is adding an extra complexity in terms of STANDARD formats. If somebody is confused by the straightforward 17MB which can be read very simply from a dialog box or panel in Photoshop or in Bridge, then what are they going to make of the idea of 3000 pixels long side as long as it is a standard format with a maximum ratio of 1.5 (3:2) which is effectively what you are saying. I can just see the explanations on here becoming an order of magnitude more complex than they are already, not to mention what the Alamy advice would entail. 

 

And how would they even work that ratio out if they can't do a simple read out in a dialog box or do a simple calculation based on the megapixel size from the Lightroom display. Presumably other software has similar. 

 

A simple bit of advice such as make sure your image is at least 6MP or 17MB in size (explain how to see this in standard imaging software) will cover everything. Yes it doesn't need to be the full 6MP but that will get them over the bar. Why they chose 17MB rather than 18MB is a bit of a mystery as that would have really simplified things.

 

But... if resizing in PS in 16 bit mode, the minimum is 34MB (and that's how it appears in PS). Obviously that becomes 17MB when the image is saved as 8 bit for Alamy, but the recommendation is to work in 16 bit mode until the final save to jpg which automatically converts to 8 bit.

 

Personally I think we should advise new users to just ensure images have at least 6,000,000 pixels as this also avoids the potential confusion over whether  Mega = 1024 x 1024 or 1,000,000. PS can be set to show the image dimensions in Pixels. Also when using the resize dialogs in PS the target dimensions are entered in pixels (not MP or MB). Obviously LR export is different.

 

Mark

 

Edited by M.Chapman

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16 minutes ago, M.Chapman said:

 

But... if resizing in PS in 16 bit mode, the minimum is 34MB (and that's how it appears in PS). Obviously that becomes 17MB when the image is saved as 8 bit for Alamy, but the recommendation is to work in 16 bit mode until the final save to jpg which automatically converts to 8 bit.

 

Personally I think we should advise new users to just ensure images have at least 6,000,000 pixels as this also avoids the potential confusion over whether  Mega = 1024 x 1024 or 1,000,000. PS can be set to show the image dimensions in Pixels. Also when using the resize dialogs in PS the target dimensions are entered in pixels (not MP or MB). Obviously LR export is different.

 

Mark

 

 

I almost agree but I am talking about checking the final JPEG that is about to be submitted and that can only be 8 bit so I don't think bit depth is an issue. It very rarely if ever comes up here as far as I can recall.  This has been going on for years and the biggest problem is mixing up size on disk with pixel dimensions so yes quote pixel dimensions.

 

But I think megapixels (MP) rather than pixels is the easier measurement to quote as everyone is familiar with MP nowadays and it is the quantity simply visible in Lightroom which I am guessing is probably the most popular software now for image processing. A lot of people don't use Photoshop nowadays and simply export to JPEG from Lightroom. Perhaps have it in brackets (6MP = 6,000,000 pixels = 18MB approx) and also up the MB limit to 18MB to make it really simple. Get it to at least 6MP and you're over the bar.  

 

But then again, this is all so basic that I have to wonder why would-be photographers don't have a grasp of the basics before trying to sell images. 

 

 

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As a postscript to this thread here are two tables showing the minimum pixel dimensions permitted for uploading to Alamy for the different formats/aspect ratios:

 

The first is the official Alamy requirement for 17MB uncompressed, the second the suggested 6,000,000 pixel alternative, both very similar in real terms of course.

 

Alamy spec. - 17MB uncompressed

                                   

Format                           Aspect ratio   Long side     Short side

Square                                1                    2438               2438

Micro 4/3                          1.33                2811               2114

Full frame/APS-C, 1”       1.5                   2985               1990

Panoramic 2:1                   2                     3447               1724

Panoramic 2.5:1               2.5                  3854               1542

Panoramic 3:1                   3                     4222               1407

Panoramic 3.5:1               3.5                   4560               1303

Panoramic 4:1                   4                      4875               1219

Panoramic 4.5:1               4.5                   5171               1149

Panoramic 5:1                   5                      5451               1090

                                   

                                   

Alternative – 6,000,000 pixels

 

Format                             Aspect ratio    Long side     Short side

Square                                   1                      2450               2450

Micro 4/3                            1.33                   2825               2124

Full frame/APS-C, 1”          1.5                   3000               2000

Panoramic 2:1                      2                      3464               1732

Panoramic 2.5:1                  2.5                   3873               1549

Panoramic 3:1                      3                      4243               1414

Panoramic 3.5:1                  3.5                   4583               1309

Panoramic 4:1                      4                      4899               1225

Panoramic 4.5:1                  4.5                   5196               1155

Panoramic 5:1                      5                      5477               1095

Edited by Harry Harrison
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10 minutes ago, Harry Harrison said:

As a postscript to this thread here are two tables showing the minimum pixel dimensions permitted for uploading to Alamy for the different formats/aspect ratios:

 

The first is the official Alamy requirement for 17MB uncompressed, the second the suggested 6,000,000 pixel alternative, both very similar in real terms of course.

 

Alamy spec. - 17MB uncompressed

                                   

Format                           Aspect ratio   Long side     Short side

Square                                1                    2438               2438

Micro 4/3                          1.33                2811               2114

Full frame/APS-C, 1”       1.5                   2985               1990

Panoramic 2:1                   2                     3447               1724

Panoramic 2.5:1               2.5                  3854               1542

Panoramic 3:1                   3                     4222               1407

Panoramic 3.5:1               3.5                   4560               1303

Panoramic 4:1                   4                      4875               1219

Panoramic 4.5:1               4.5                   5171               1149

Panoramic 5:1                   5                      5451               1090

                                   

                                   

Alternative – 6,000,000 pixels

 

Format                             Aspect ratio    Long side     Short side

Square                                   1                      2450               2450

Micro 4/3                            1.33                   2825               2124

Full frame/APS-C, 1”          1.5                   3000               2000

Panoramic 2:1                      2                      3464               1732

Panoramic 2.5:1                  2.5                   3873               1549

Panoramic 3:1                      3                      4243               1414

Panoramic 3.5:1                  3.5                   4583               1309

Panoramic 4:1                      4                      4899               1225

Panoramic 4.5:1                  4.5                   5196               1155

Panoramic 5:1                      5                      5477               1095

Edited just now by Harry Harrison

Now that seems very clear and easy to understand.👍

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1 hour ago, jodyko said:

Now that seems very clear and easy to understand.👍

 

It is not difficult but is it easier than simply reading out a number in Photoshop or Lightroom? I would say no. Besides these refer all to regular sizes. What if you crop your image to something irregular which I often do such as 2950x2000. You would have to do a calculation which both Photoshop and Lightroom do for you. All you need to know is where to look.

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On 19/09/2019 at 19:56, MDM said:

 

It is not difficult but is it easier than simply reading out a number in Photoshop or Lightroom? I would say no. Besides these refer all to regular sizes. What if you crop your image to something irregular which I often do such as 2950x2000. You would have to do a calculation which both Photoshop and Lightroom do for you. All you need to know is where to look.

 

Not everyone uses PS or LR though. But every package I've used allows inspection of the pixel dimensions and they are visible whilst cropping or resizing whereas MB usually isn't.

 

Let's face it, pretty much all the confusion arises because Alamy 17MB uncompressed size limit keeps being confused with the compressed jpg file size in MB. So let's ditch trying to explain MB which is a rather secondary derived quantity from the pixel dimensions, the bit depth and suffers confusion over whether Mega = 1,000,000 or  1,048,576. We don't sell images according to MB and I think Alamy are now in the minority in expressing their upload sizes this way .

 

Here's my suggested text for Alamy to use on their help page, or pin in this forum?

 (Thanks to Harry Harrison for the table)

 

Change from 

  • File size of over 17MB (when uncompressed/open)
    Your JPEG file is likely to have a compressed size of 3-5MB. Opening a JPEG in an image program such as Adobe Photoshop will show you the uncompressed/open file size.

to

  • Image size
    Alamy accepts images which contain at least 17MB of uncompressed 8 bit image data. As a simplified guide, this requirement can be met by submitting images that contain at least 6,000,000 pixels. The following are examples of the minimum image pixel dimensions that meet this simplified requirement.

Format                             Aspect ratio    Long side     Short side

Square                                   1                      2450               2450

Micro 4/3                            1.33                   2825               2124

Full frame/APS-C, 1”          1.5                   3000               2000

Panoramic format images with more than 6,000,000 pixels images are also accepted 

 

Mark

Edited by M.Chapman
Edited to remove incorrect statement about MP
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2 hours ago, MDM said:

What if you crop your image to something irregular which I often do such as 2950x2000

Agreed.

 

2 hours ago, M.Chapman said:

Not everyone uses PS or LR though

I use Adobe Elements and Gimp. Beginning to get along with Darktable as well.

 

2 hours ago, MDM said:

You would have to do a calculation which both Photoshop and Lightroom do for you

I'm not finding the calculation while cropping in Gimp or Elements although I do get running dimensions, (inches in Elements.)  Haven't tried in Darktable. It's entirely possible that I'm ignorant of something in these programs. A size calculation would be welcomed by me. In the absence of one I can certainly open an additional dialog that will give me the information after cropping. Alamy SizeCheck has just been very convenient for me to use when in doubt. I've actually been better educated following this thread and hope the OP has gained some knowledge as well.

Edited by jodyko
Phrase

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1 hour ago, M.Chapman said:
  • Image size
    Alamy accepts images which contain at least 17MB of uncompressed 8 bit image data. As a simplified guide, this requirement can be met by submitting images that contain at least 6,000,000 pixels. The following are examples of the minimum image pixel dimensions that meet this simplified requirement.

Format                             Aspect ratio    Long side     Short side

Square                                   1                      2450               2450

Micro 4/3                            1.33                   2825               2124

Full frame/APS-C, 1”          1.5                   3000               2000

Panoramic format images with more than 6,000,000 pixels images are also accepted 

BTW I like this too.

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1 hour ago, M.Chapman said:

(Thanks to Harry Harrison for the table)

My pleasure, I can't resist a nice little spreadsheet!

 

Yes, the panoramics were just for illustration, they can of course be any aspect ratio over 2:1 as MDM says so they don't fit into a table format well. I also probably wouldn't recommend the more extreme crops, they must surely have limited usefulness at that resolution even if technically they should pass QC.

 

Also of course anyone is at liberty to crop their pictures in any direction without it being for a panoramic so they will still need to be able to work out the size.

 

I think the simplified table would be very useful on the appropriate Alamy page and should at least stop new contributors going down any blind alleys in terms of misunderstanding jpeg size.

Edited by Harry Harrison
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11 hours ago, jodyko said:

I'm not finding the calculation while cropping in Gimp or Elements although I do get running dimensions, (inches in Elements.) 

 

In PSE (and PS) you can change the units in preferences or by clicking on the little arrow or triangle at the end of the little display box.

 

Mark

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5 hours ago, M.Chapman said:

In PSE (and PS) you can change the units in preferences

Thanks Mark.

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18 hours ago, MDM said:

 

It is not difficult but is it easier than simply reading out a number in Photoshop or Lightroom? I would say no. Besides these refer all to regular sizes. What if you crop your image to something irregular which I often do such as 2950x2000. You would have to do a calculation which both Photoshop and Lightroom do for you. All you need to know is where to look.

 

 

where do i find this number in C1?

 

hum, 2950x2000=5,900,000<6,000,000 so don't do such in your first submission. 

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19 hours ago, MDM said:

It is not difficult but is it easier than simply reading out a number in Photoshop or Lightroom? I would say no. Besides these refer all to regular sizes. What if you crop your image to something irregular which I often do such as 2950x2000. You would have to do a calculation which both Photoshop and Lightroom do for you. All you need to know is where to look.

Mark enlightened me on how to do this in Elements and yes, very easy, and just a matter of knowing where to look. Thanks.

 

 

6 hours ago, M.Chapman said:

 

In PSE (and PS) you can change the units in preferences or by clicking on the little arrow or triangle at the end of the little display box.

 

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7 hours ago, M.Chapman said:

clicking on the little arrow or triangle at the end of the little display box

This can give me a size.  👍

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2 hours ago, meanderingemu said:

 

 

where do i find this number in C1?

 

hum, 2950x2000=5,900,000<6,000,000 so don't do such in your first submission. 

 

Yes that was my point  - you can't tell simply from a quick readout of the pixel dimensions, you have to a do the calculation and then actually convert it into MB to see if it would pass Alamy. The fact that it is less than 6MP is not definitive as it could be  < 6MP and still >17MB. Much easier to just get a readout in Photoshop. I can't help with C1 as I have never used it but the online help should work I imagine if it as good as people say it is 😀.

Edited by MDM
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