Gary Clarke Posted November 10, 2014 Share Posted November 10, 2014 As a relative newcomer I'm getting a bit confused about the file size requirements and would appreciate a bit of advice please. I know it's a requirement to submit JPEGS with an uncompressed file size of 17MB and based on that I had assumed that my old Nikon D300 images wouldn't be suitable as these tend to produce RAW images of around 9-10MB (I'm not talking not MPixels which for that camera is 12). But I notice it is on the list of recommended cameras. So as an example, I exported (from Lightroom) a D300 RAW image that was showing at 9.63MB in Lightroom and that produced a JPEG of just over 7MB (I had the LR export settings as JPEG, sRGB, file size no limit, resolution 300ppi). Oddly looking at the RAW file in Finder it was showing as 10.1MB, not 9.63MB as in Lightroom. As an experiment I exported the same RAW file to Photoshop and simply saved it with no editing whatsoever and it resulted in saved file sizes in Lightroom of 69.92MB (as both PSD and TIFF, again both were bigger in Finder?), i.e. well above the 17MB minimum. But when I exported these from Lightroom it resulted in the same JPEG file size of 7MB. So what is required - save the image as PSD or TIFF first to get about the minimum and then save the JPEG from that? Or am I missing the point? (I probably am). Haven't had this problem before as file sizes from Fuji XT1 and especially Nikon D800 seem to easily large enough by simply exporting as a JPEG from the Lightroom RAW file. So, help please. Getting totally lost with this! Link to comment Share on other sites More sharing options...
Martin Carlsson Posted November 10, 2014 Share Posted November 10, 2014 The imagesize requirement that you will have to look at to see if it is big enough is an UNCOMPRESSED 8-BIT TIFF - easiest to check in PS at the bottom left-hand corner when the file is open or by hitting CTRL+ALT+I Don't forget to make sure you are in 8-bit mode first. Both ways will give you the imagesize as an uncompressed image regardless of fileformat i.e. all images with the same pixeldimensions and bit-size will be the same size (mb) regardless if they are Jpeg, Tiff, PSD etc. Filesize on your HDD will vary depending on fileformat, compression etc. Size of images on your HDD is largely irrelevant unless you produce massively large Jpegs. Link to comment Share on other sites More sharing options...
woody Posted November 10, 2014 Share Posted November 10, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me Link to comment Share on other sites More sharing options...
Gary Clarke Posted November 10, 2014 Author Share Posted November 10, 2014 Thanks! I have LR set to pass files to PS as 16-bit PSDs (or TIFFs) and was viewing the consequent file size that way. When I change Image Mode to 8-bit I now get the uncompressed size. I must admit no matter how long I've been taking photographs I seem to have a mental block with sizes, resolution, bit-size, pixel dimensions etc etc. Taking photos is so much easier! Thanks again. Link to comment Share on other sites More sharing options...
spacecadet Posted November 10, 2014 Share Posted November 10, 2014 6MP now- have they reduced it again? I'm sure it was 8 the other week. Link to comment Share on other sites More sharing options...
spacecadet Posted November 10, 2014 Share Posted November 10, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me To be fair it does now give both MP and uncompressed jpeg size requirements. Link to comment Share on other sites More sharing options...
John Mitchell Posted November 10, 2014 Share Posted November 10, 2014 6MP now- have they reduced it again? I'm sure it was 8 the other week. Min size changed about a month ago. There was a forum discussion about it. Guess you were out of town. Link to comment Share on other sites More sharing options...
Mark Baigent Posted November 10, 2014 Share Posted November 10, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet Link to comment Share on other sites More sharing options...
Guest Posted November 10, 2014 Share Posted November 10, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet +1 Link to comment Share on other sites More sharing options...
John Mitchell Posted November 10, 2014 Share Posted November 10, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet I've never dealt with anyone who speaks in megapixels either. MB makes much more sense. However some image-request services do specify pixels -- e.g. minimum 3000 pixels on the long side. I've also had private clients specify pixels (but not MP), especially for Web use. Link to comment Share on other sites More sharing options...
Martin P Wilson Posted November 10, 2014 Share Posted November 10, 2014 For an uncompressed file (e.g. 8 bit TIFF): Mpixels = Mbytes / 3 (i.e. 8Mpx = 24Mbytes/3) OR Mbytes = Mpixels * 3 (17Mbytes - 3 * 5.67Mpx) JPG are a compressed format and size (for a given quality) depends on the nature of the image (masses of blue sky compresses to a smaller file size than a detailed image e.g. foliage). It is why high ISO do not compress so well - noise looks like detail to the compression process. RAW are proprietary and often have some degree of lossless compression so size again depends on nature of image but is often around similar size to a TIFF or a bit smaller if it is compressed. PSD is complex as it depends on the image and nature of the processing and adjustments that are embedded i it - so usually bigger. Link to comment Share on other sites More sharing options...
spacecadet Posted November 10, 2014 Share Posted November 10, 2014 6MP now- have they reduced it again? I'm sure it was 8 the other week. Min size changed about a month ago. There was a forum discussion about it. Guess you were out of town. Quite right, I wasn't out of town but I obviously latched on to the 24, forgetting we went down to that about 4 years ago. Good news for SoLD- down to 3000px long side I go! Link to comment Share on other sites More sharing options...
John Mitchell Posted November 10, 2014 Share Posted November 10, 2014 6MP now- have they reduced it again? I'm sure it was 8 the other week. Min size changed about a month ago. There was a forum discussion about it. Guess you were out of town. Quite right, I wasn't out of town but I obviously latched on to the 24, forgetting we went down to that about 4 years ago. Good news for SoLD- down to 3000px long side I go! I haven't had to go that low yet, but I suppose it's an option. I find that resizing to 4000 pixels (30 MB) or 3600 (24 MB) is usually adequate for most "iffy" images. Hate when I have to downsize images, though, as it can limit some types of sales opportunities. OK for most editorial, though. Link to comment Share on other sites More sharing options...
woody Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet OK so some people refer to spades as earth inverting horticultural implements. The fact is that the uncomplessed file size is is a consequence of the image dimensions in pixels so it is a case of adding a layer of abstraction that has absolutely nothing to do with photography and is confusing for those who don't understand information storage or are unaware of "industry standards". Link to comment Share on other sites More sharing options...
Phil Robinson Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me If you are cropping or resizing images I think the MB is the more useful measure - MP is useful when chosing a camera. Link to comment Share on other sites More sharing options...
Mark Baigent Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet I've never dealt with anyone who speaks in megapixels either. MB makes much more sense. However some image-request services do specify pixels -- e.g. minimum 3000 pixels on the long side. I've also had private clients specify pixels (but not MP), especially for Web use. Yes, I get asked for web specific sizes ie 600px x 400px, that is very common. Link to comment Share on other sites More sharing options...
Guest Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet OK so some people refer to spades as earth inverting horticultural implements. The fact is that the uncomplessed file size is is a consequence of the image dimensions in pixels so it is a case of adding a layer of abstraction that has absolutely nothing to do with photography and is confusing for those who don't understand information storage or are unaware of "industry standards". Megapixels is the equvalent of earth inverting horticultural implements, MB and pixels dimensions were about from the days of film and scanning so megapixels is the cuckoo in the nest.......... I'd love to know how I work out what the megapixel size of a Blender render is....... and yet I can just look at the file in PS and see exactly what the pixel lengths are but more importantly, the size of the uncompressed file which is the one asked for by all my agents. Link to comment Share on other sites More sharing options...
Mark Baigent Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet OK so some people refer to spades as earth inverting horticultural implements. The fact is that the uncomplessed file size is is a consequence of the image dimensions in pixels so it is a case of adding a layer of abstraction that has absolutely nothing to do with photography and is confusing for those who don't understand information storage or are unaware of "industry standards". It is industry standard for a reason. Lets say for instance you make a photograph on a 16mp camera and then crop it a tiny bit, it is then not 16mp, it is far easier to refer to the uncompressed file size than work out the new MP. The way Alamy presents the information is very good (5397 x 3594 45.7 x 30.4 cm (300 dpi) 55.5 MB) and tells the buyer all that they need. Oh, if you are in an industry it is important to understand (or learn) the standards, I suspect that goes for most industries. Link to comment Share on other sites More sharing options...
woody Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet OK so some people refer to spades as earth inverting horticultural implements. The fact is that the uncomplessed file size is is a consequence of the image dimensions in pixels so it is a case of adding a layer of abstraction that has absolutely nothing to do with photography and is confusing for those who don't understand information storage or are unaware of "industry standards". Megapixels is the equvalent of earth inverting horticultural implements, MB and pixels dimensions were about from the days of film and scanning so megapixels is the cuckoo in the nest.......... I'd love to know how I work out what the megapixel size of a Blender render is....... and yet I can just look at the file in PS and see exactly what the pixel lengths are but more importantly, the size of the uncompressed file which is the one asked for by all my agents. When I render, I specify DPI, width and height and know (before rendering) the dimensions in MP. I can figure out the uncompressed file size but that does involve a calculation. The uncompressed size is something that is only relevant while the file is in RAM but the real world bits that are important are the size when viewed / printed (surely this is the end game?)and, to a lesser extent, the space required for storage. MP relates directly to the image whether cropped or not and is totally understandable and accessible. If this is the industry standard I would have to ask why, i.e. is there a solid practical reason or is it just smoke an mirrors to confuse the unwashed masses? Link to comment Share on other sites More sharing options...
Guest Posted November 11, 2014 Share Posted November 11, 2014 17 MB is another way of saying 6 MP - why they don't just say this and persist with file size (most people have difficulty in understanding) rather than image dimensions (everyone understands) is beyond me It is industry standard to use MB, I have never met a client that talks in mega pixels....... yet OK so some people refer to spades as earth inverting horticultural implements. The fact is that the uncomplessed file size is is a consequence of the image dimensions in pixels so it is a case of adding a layer of abstraction that has absolutely nothing to do with photography and is confusing for those who don't understand information storage or are unaware of "industry standards". Megapixels is the equvalent of earth inverting horticultural implements, MB and pixels dimensions were about from the days of film and scanning so megapixels is the cuckoo in the nest.......... I'd love to know how I work out what the megapixel size of a Blender render is....... and yet I can just look at the file in PS and see exactly what the pixel lengths are but more importantly, the size of the uncompressed file which is the one asked for by all my agents. When I render, I specify DPI, width and height and know (before rendering) the dimensions in MP. I can figure out the uncompressed file size but that does involve a calculation. The uncompressed size is something that is only relevant while the file is in RAM but the real world bits that are important are the size when viewed / printed (surely this is the end game?)and, to a lesser extent, the space required for storage. MP relates directly to the image whether cropped or not and is totally understandable and accessible. If this is the industry standard I would have to ask why, i.e. is there a solid practical reason or is it just smoke an mirrors to confuse the unwashed masses? Just open an image in Photoshop, the MB is displayed in the open file...no mention of megapixels. Open the file size dialog in PS, no mention of megapixels....the lead number is the MB file size. Just had a look in LR at the IPTC dialog and cannot find megapixels....I can see the 'on file' size and the pixel dimensions. The only place I can see MP is by looking at a camera website... The confusion is always between uncompressed and compressed files sizes. MP, MB and pixel dimensions are secondary to what confuses people. I can't see there's anything easier than looking at a file in software and seeing a number. I don't need to justify the industry standards, that's the whole point...they are the things to which we adhere...or not. Anyhow....off to shoot some corporate portraits.... they will be delivered in MB and pixel lengths.....and MP if I can work out how to work out MP. Link to comment Share on other sites More sharing options...
Mark Baigent Posted November 11, 2014 Share Posted November 11, 2014 When I render, I specify DPI, width and height and know (before rendering) the dimensions in MP. I can figure out the uncompressed file size but that does involve a calculation. The uncompressed size is something that is only relevant while the file is in RAM but the real world bits that are important are the size when viewed / printed (surely this is the end game?)and, to a lesser extent, the space required for storage. MP relates directly to the image whether cropped or not and is totally understandable and accessible. If this is the industry standard I would have to ask why, i.e. is there a solid practical reason or is it just smoke an mirrors to confuse the unwashed masses? Woody Industry standards develop because they work not to annoy others IME. I guess it may be a hang over from the days when most of my work was in RAW then TIFF which meant file sizes can be seen in Windows explorer or similar, I/we only ever used JPEGs for posting images out on a CDs. Link to comment Share on other sites More sharing options...
dustydingo Posted November 11, 2014 Share Posted November 11, 2014 If this is the industry standard I would have to ask why, i.e. is there a solid practical reason or is it just smoke an mirrors to confuse the unwashed masses? You have a couple of choices here: Rail against the industry standard and supply/describe/communicate according to your wants/preferences or Supply/describe/communicate according to what the customer prefers/wants--in most examples given by your peers here, that would appear to be in line with the industry standard. One of the above will make your customers happy as you will be seen to be doing what they prefer, the other will make you happy. dd Link to comment Share on other sites More sharing options...
MDM Posted November 11, 2014 Share Posted November 11, 2014 For the benefit of anybody who does not know, the conversion between Megapixels and Megabytes is incredibly simple. Megabytes = 3 X Megapixels for an 8-bit file and = 6 X Megapixels for a 16-bit file. As for industry standards, the insistence on using the erroneous term dpi rather than the correct ppi when referring to a digital image is perhaps the second most confusing thing for newcomers to digital imaging (after the subject of this thread). Image resolution is not measured in dots per inch, it's pixels per inch. The second most annoying thing in the universe after misplaced apostrophe's. Link to comment Share on other sites More sharing options...
woody Posted November 11, 2014 Share Posted November 11, 2014 If this is the industry standard I would have to ask why, i.e. is there a solid practical reason or is it just smoke an mirrors to confuse the unwashed masses? You have a couple of choices here: Rail against the industry standard and supply/describe/communicate according to your wants/preferences or Supply/describe/communicate according to what the customer prefers/wants--in most examples given by your peers here, that would appear to be in line with the industry standard. One of the above will make your customers happy as you will be seen to be doing what they prefer, the other will make you happy. dd This is true Actually my only point is that, in communicating something, it is usually better to use terms that are readily understandable by your audience. The pros and the more IT literate will understand but the majority of new people starting out / joining apparently don't, based on the number of times it come up. @MDM That MP to MB calculation is slightly off - your method can be used to derive the total number of bytes but you have to divide by 1024*1024 to get MB (a 6 MP image is approx. 17 MB, not 18 MB). Also, I don’t believe (although open to argument) that PPI means a whole lot in image terms as the physical size of what you view depends on, and only on, the resolution of the monitor – it does make a difference when printing though which is more a DPI thing Link to comment Share on other sites More sharing options...
M.Chapman Posted November 11, 2014 Share Posted November 11, 2014 As a computer scientist and photographer I've a foot in both camps (MB and MP). I've also spent time on standards committees drafting industrial standards. A key aspect of a standard is that it should allow clear and concise communication that is easy to understand as practical by all potential users. So I'm with Woody on this one. Whilst MB may be the "industry standard", in my opinion it's a poor choice. MP would be much better. You only have to look at the number of questions raised in this forum by photographers on this topic to see that using MB is not the best method of communicating the image size requirements. Using MB risks confusion as a result of varying bit depth (8 or 16 bit) and image compression levels as well as being a derived value. I prefer to quote either MP or pixel dimensions, but will happily work to any requirement. (I've had requests for physical size at 300PPI, MP, MB and pixel dimensions). That's my two penneth worth (FX runs for cover). Link to comment Share on other sites More sharing options...
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