smaller file size after cropping – is this normal

IW
Posted By
Iain Williams
Oct 23, 2003
Views
1269
Replies
36
Status
Closed
Greetings!

I am not sure whether this is normal or not. I hope someone can help me.

When I crop an image from my 5 meg camera which maybe 4 MEGS in size the file size drops to around 800 KB. This is without enlarging the image. I would have thought the file size would remain almost the same, especially if you are only cropping around the outside of the image. Thanks in advance………..Iain (Australia)

How to Master Sharpening in Photoshop

Give your photos a professional finish with sharpening in Photoshop. Learn to enhance details, create contrast, and prepare your images for print, web, and social media.

BH
Beth_Haney
Oct 23, 2003
What format are you working in?
IW
Iain Williams
Oct 23, 2003
Hi Beth

Thanks for the reply. By format I assume you mean .jpg?

I open up the .jpg, select the crop tool and crop the picture then press save.

I notice that when I check the file size the cropped image is much lower than the original…………Iain
BH
Beth_Haney
Oct 23, 2003
I can’t actually explain this to you, because I don’t know enough about all of the intricate workings of file compression, but I can say that you should never work on a file while it’s in JPEG. That’s a "lossy" format, meaning that each Save compresses the image and the file size diminishes each time. What you’re describing sounds like an AWFUL lot of loss for just one change, but from here on out, always take the images from your camera and immediately convert them to either TIFF or PSD before doing any editing. Both of those are non-lossy formats, and all of your original digital information will be retained through countless manipulations and saves. If you need a JPEG format image for some reason, that can easily be done using one of the other features for converting.

Like I said, I can’t begin to explain what happened if this was a very sudden loss – like open at 4MB and close at 800KB. However, us "oldtimers" do an immediate conversion to non-lossy and also archive the original camera image. The only thing I can think of is that the compression setting must have been set it such a way as to make that a mighty teensy little file.
IW
Iain Williams
Oct 23, 2003
Hi again Beth

WOW!! I just did a few trial images to compare file size, resolution etc using the method you suggested (covert from .jpg to .tiff – then crop in .tiff format and re save in .tiff format).

The difference is amazing. File sizes are huge, even after a tight cropping!

A quick question. I use .jpg just because that is what comes out of the camera. It is also easy to e-mail a .jpg, and I guess that is what I started out using a few years back!

From your mail and some quick reading I have just done, I am lead to beleive that the .tiff format will protect the image data (colour, etc) in such a way that it will not be affected everytime you re-size the image, etc. Is this true? I guess what I am asking is what are the benifits in saving in .tiff to .jpg? Are .jpg’s that bad for taking a photo?

Lastly, and you may not know this, but can you post to a website using .tiff. I would image you would have to convert the .tiff to .gif or .jpg before uploading due to file size.

MANY THANKS BETH………..Iain
BH
Beth_Haney
Oct 23, 2003
lain, I hope you don’t mind, but I’m going to postpone responding to your question until tomorrow morning. I just had a kind of stressful evening, and I’m not sure how coherent my answer would be!

A quick answer to one question – JPEGs are a widely accepted format for images saved to a camera card. It’s what many of the most common cameras use, and that’s fine. It’s what happens to them after they come off the card that is much more critical.

More tomorrow – unless somebody beats me to it! Goodnight! 🙂
IW
Iain Williams
Oct 23, 2003
Beth – Thanks for your help here. I look forward to talking at a later time. It really helps to speak to someone who actually knows the ins and outs of this.

Briefly, My camera (Canon G5) will save in either RAW or .JPG. I usually select .JPG and go from there. From what I understand you are suggesting to convert to .tiff immediately after downloading from the camera. Then, do all your image manipulation on the .tiff file. Then, if you wish convert back to a .jpg for e-mailing and web hosting. Oh, and also keep the original manipulated .tiff image as a backup.

Enjoy the remainder of your evening..Iain
NS
Nancy_S
Oct 23, 2003
lain,

It is the opening and subsequent repetitive saving of jpgs which degrade the quality, though there is much discourse as to the degree and at what point does the quality become noticably inferior. Each save necessitates the image again being compressed and artifacts will begin to show.

Some people choose to download images from their camera (in jpg, the camera’s native format) to a specially created folder which will serve as the container for their ‘negatives’. The files will reside there in their pristine, unaltered state. Copies of these files are used for editing. This approach might be the best for someone who is a bit strapped for space on their harddrive. Most of us use a CD burner to burn all of our originals to CD.

Others, myself included, with tons of HD space, download the images and immediately use the Batch command to convert the whole lot to .psd format. This is PSE’s native format and is lossless. I burn the originals to CD and work from copies only. The only negative to the .psd format (besides the large file size) is one must have an Adobe program to open them with whereas everyone can open a tiff. But .psd is a good choice to edit in. If one wants to email or display on a website an image, you would use the ‘Save for Web’ feature which will drastically reduce the file size and offers choices of jpg, gif etc for saving.

The large file size discrepancy you saw could have been the difference of comparing a version which was open on your computer versus just looking at a file size as reported in your browser for example. Of course, the unopened one is compressed and the open one not.

I suggest a great site for you to check out. Wayne clearly explains many concepts which need be understood to have the most satisfiying fun with digital image editing.

<http://scantips.com>

Nancy
IW
Iain Williams
Oct 23, 2003
Hello Nancy

Thank you for your comprehensive e-mail – I appreciate the time you have taken. I read Wayne’s site with interest and must admit I’ve learnt quite a lot today!

I’ve decided to do a total re-think on how I store my images. I will follow your example of keeping .tiff or .psd as a master and then making a .jpg of that when required.

Do you know if there is a big diffeence between .psd and .tiff? Wayne actually says that .png is just as good as .tiff but with a smaller file size. Any comments here?

You mentioned the batch command in your mail. WOW!! I did not know the batch command existed. I have been conerting each image individually which as you know is very time consuming.

On another note, and I hope you don’t mind my "foolish" beginner questions. Images for a website need to have their pixel size reduced. I have been using the adobe image resize command and selecting 600 or 800 in the width. The program then automatically figures out the height number required to produce a suitable sized image. Overall the image looks OK.

I note that the batch command allows you to do this automatically, however you must input both the height and width. I find when I do this – say 600 x 450 pixels, some images are great whilst others a skewed. Is there a way to batch images to a certain height or width with the program figuring out the other number (similar to if you were resizing each image manually as mentioned above)?

Thanks…………………Iain
SS
Susan_S.
Oct 23, 2003
Hi Iain – good to see another Australian here! I use a G3 rather than a G5, and generally shoot JPG rather than RAW. As the others have said, the problem comes when you have repeated resaves on jpg files -and the higher the degree of (lossy) compression the worse the effects – increased artefacts, particularly seem to be noticeable in flat areas of blue sky and where light and dark contrasting areas meet.

My work-flow is similar to others – I download all the original JPG files from the camera onto my hard-drive, backing up onto CD. Then any that I open and edit are resaved as PSD files to avoid any further degradation – the rule that I use is that only "final use" edited files get saved as jpgs – images for display on the web ( the psd and tiff files are a bit weighty, even if I did have broadband!), or for emailing – I usually use save for web to do this, and always make sure that I have saved a psd version first if there is any chance that I will need to come back to it and edit again.

My guess at your original question is that you had the options on the jpg compression dialogue set to low quality, resulting in a much smaller file on saving – and of course causing a much bigger degradation of image quality.

If you are into experiments, opening and re-saving a jpg at low quality several times – one with tree branches against a blue sky really shows up the effect easily! – and then examining at 100 percent is quite interesting – image quality falls off noticeably. With resaving at the maximum quality the effect is much harder to see.

Susan S.
IW
Iain Williams
Oct 23, 2003
Thanks Susan, I have spent most of the day experimenting. As you will see from my replies to the others, I am now having a total re-think about how I save images!…….Iain
IW
Iain Williams
Oct 23, 2003
Hi everyone again!

I must be doing something wrong here. This is what happens.

I download from my camera in .jpp format. I then convert all the images to either .tiffs or .psds and manipulate, crop,edit the image and save again in that format. I then batch command and revert back to .jpgs.

The original .jpg is 4 megs thereabouts. Conversion to .tiff increases file size to 14000 megs and conversion back to .jpg reduces file size to 400kb. This is what I don’t understand. Surely the .jpg should be quite large matching what it was at the beginning of the process? Perhaps I have something set up incorrectly.

The .jpgs look good at 400kb so maybe adobe automatically calculates the optimum size for the .jpg during the coversion from .tiff.

ANY IDEAS???? Thanks……………Iain
IW
Iain Williams
Oct 23, 2003
Hello, I think I have it sorted and I hope someone reading this can point me in the right direction.

The jpeg options box is always set to small file size. That explains the small file size. I know how to set the options to high manually for each image, but how do you set the option to always read high so that the batch command will convert correctly??

Cheers – Iain
BH
Beth_Haney
Oct 23, 2003
Hi, lain, I’m back and see you’ve gotten a lot of help from two people who are extremely good with Elements! I don’t have anything to add to the discussion, except to address the question in your final paragraph.

Which version of Elements are you using? One of our complaints about version 1 was that there was no way to control the amount of JPEG compression through the Batch process. In version 2, you can select to save to Low, Medium, High, and Maximum. Are you seeing that in the selection box on the Batch processing screen in the list of file formats? If not, are you using version 1? If you are, you might want to go back to doing your final saves back to JPEG manually.
NS
Nancy_S
Oct 23, 2003
lain,

In response to your ‘skewed’ photos when resizing for the web. The problem is that you are dictating both dimensions. This could, as you have discovered, produce distorted images. An image has a certain aspect ratio. This ratio varies by camera and certainly varies according to your cropping desires. So, the thing to do is create a copy of your image and with Image Resize (with Resample and CONSTRAIN checked) type in the desired dimensions for ONE dimension and allow the program to fill in the other variables. This will maintain the aspect ratio of your image. Since we are only concerned with output to screen on our copy, the only consideration is the image size in terms of how many pixels by how many pixels is the image (how much of a monitor’s screen will the image cover). The resolution (in terms of ppi) for screen viewing is immaterial. Proceding this way will clear up your skewed problem.

Nancy
NS
Nancy_S
Oct 23, 2003
lain,

yikes…pardon the spelling mistakes earlier…

A compliment to you: because you exactly define your actions and give details, one can ‘cut to the chase’ and get to the heart of the matter in trying to help you. This is appreciated.

Again, I can’t stress enough…save/burn your originals AS IS, the original, pristine, unedited images. Work always on a duplicate/copy. Save your edited copies (not save over your originals). As your skills improve, it is very likely you would want to rework your best shots and beginning again with a ‘clean slate’ is the way to go.

Nancy
NS
Nancy_S
Oct 23, 2003
lain,

I would suggest your next endeavor be learning how to use adjustment layers in the program. This gives you editing which is non-destructive to the image and changable. Begin by always having your Layers Palette visible on the side of your screen. Double click the ‘background’ layer to begin to change it into a regular layer. There are thousands of excellent tutorials on the internet, easily accessible using Google.

To give you an idea of the possibilities using PSE…there is an off-site web area, separate from Adobe, maintained by the generosity of Grant Dixon, called the Challenge. An image is presented weekly, contributors manipulate it as desired and Grant posts these edited versions. The top left thumbnail is the starting image. Each thumbnail will give a larger version when clicked. There are presently 6 pages.

<http://www.cavesofice.org/~grant/Present/index.html>

Nancy
IW
ID_Williams
Oct 24, 2003
Hi Beth and Nancy,
Thank you for your prompt and informative replies (also well written).

I am currently using Elements 1 which explains why I cannot use the batch command to convert .tiffs to large file size .jpgs. You can only do this conversion manually image by image using Elements 1. I believe Elements 2 allows you to use the batch command in this way. I will have to look at purchasing Elements 2.

What I have decided to do is immediately convert all the .jpgs that come from my camera (G5)to either .tiff or .psd files. This will be my storage/archive files. I will then make a copy of these files to edit, manipulate and so forth and save to that file only. I will then convert these to .jpgs as required for web viewing and/or e-mailing. What do you recommend as the best format – .tiff or the .psd file??

I must admit the whole process is rather long-winded, but if the end result is better then I guess it is worth doing it.

You guys must have HUGE HD systems and 100’s of CDs!!!! I’m currently running 120 GIG.

Lastly, and I promise this will be my last question. Is there an optimum .jpg file size, or does the size really relate to the usage?

THANK YOU EVERYBODY. This forum is excellent………..Iain
CS
Chuck_Snyder
Oct 24, 2003
Iain, there really isn’t a good reason to convert your original, unedited jpegs for archiving purposes; they’ll take up much less space on your hard drive. So long as they haven’t been edited, they’re as pristine as when they emerged from your camera and they aren’t improved by decompression and saving as tiff or jpeg It’s only when you start editing that you want to save as tiff or psd. I generally save as tiff, because some image programs won’t open a psd.

Chuck
IW
ID_Williams
Oct 24, 2003
HI Chuck,

Ah I see – my misunderstanding here.

When you have edited the .tiff and like it, do you re-save as a .tiff then convert to .jpg, or keep it as a .tiff? Iain
CS
Chuck_Snyder
Oct 24, 2003
Iain, once I start editing, I never go back to jpg, other than to make copies for e-mail/web purposes. The edited pictures take up a lot more space than the originals, what with the 10/1 multiplier for tiff from jpg and the use of layers. I guess if I ever really ‘finished’ editing an image, it would be okay to go back to jpg – but I always hold out hope that I’ll learn a new technique (here!) and turn a mediocre image into a good one!

🙂

Chuck
BH
Beth_Haney
Oct 24, 2003
Yup, what Chuck said. 🙂
IW
ID_Williams
Oct 24, 2003
THANKS guys. I understand completely (must be a first for me). I guess I will be busy this weekend converting and manipulating!

Enjoy the remainder of the week…………..Iain
J
jhjl1
Oct 24, 2003
Since you have the option to shoot in RAW mode that may be your best bet. You can save your raw file as your digital negative while extracting a TIFF to have a file to work with. RAW gives you more latitude in the beginning to get your exposure settings correct.

Possible Workflow:
1.Import RAW
2.Make Exposure Corrections
3.Extract Corrected TIFF From RAW File
4.Make Any Further Corrections To TIFF In Elements (keep all TIFF files on HD)
5.Make JPEG Copies Of TIFF When Needed
6.Burn All RAW Files to CD for Archive.

The beauty in this is that you still have the original RAW even though you made corrections before extracting TIFF. Remember that when shooting in JPEG that the camera itself is doing some compression on the file before you access it on the computer.


Have A Nice Day,
jwh 🙂
My Pictures
http://www.pbase.com/myeyesview

"Iain Williams" wrote in message
Beth – Thanks for your help here. I look forward to talking at
a later time. It really helps to speak to someone who actually knows the ins and outs of this.
Briefly, My camera (Canon G5) will save in either RAW or .JPG.
I usually select .JPG and go from there. From what I understand you are suggesting to convert to .tiff immediately after downloading from the camera. Then, do all your image manipulation on the .tiff file. Then, if you wish convert back to a .jpg for e-mailing and web hosting. Oh, and also keep the original manipulated .tiff image as a backup.
Enjoy the remainder of your evening..Iain
CS
Chuck_Snyder
Oct 24, 2003
James, what advantage do you see in making the exposure corrections before converting from RAW to TIFF? Could you achieve the same or better corrections with Elements? I haven’t tried corrections to my Canon RAW Elements with either Canon software (miserable program!) or BreezeBrowser (third-party conversion program, pretty nice) because I thought what was available in Elements was more sophisticated. Your guidance would be appreciated!

Chuck
MM
Michael Moody
Oct 24, 2003
I just have to get in here with a question. Last week, someone who I thought was pretty knowledgable in this field, said he never burns to CD’s because they deteriorate and you lose the images; he only stores on his HDD. I never heard of a CD detriorating nor do I believe they can.

Any opinions?

wrote in message
lain,

It is the opening and subsequent repetitive saving of jpgs which degrade
the quality, though there is much discourse as to the degree and at what point does the quality become noticably inferior. Each save necessitates the image again being compressed and artifacts will begin to show.
Some people choose to download images from their camera (in jpg, the
camera’s native format) to a specially created folder which will serve as the container for their ‘negatives’. The files will reside there in their pristine, unaltered state. Copies of these files are used for editing. This approach might be the best for someone who is a bit strapped for space on their harddrive. Most of us use a CD burner to burn all of our originals to CD.
Others, myself included, with tons of HD space, download the images and
immediately use the Batch command to convert the whole lot to .psd format. This is PSE’s native format and is lossless. I burn the originals to CD and work from copies only. The only negative to the .psd format (besides the large file size) is one must have an Adobe program to open them with whereas everyone can open a tiff. But .psd is a good choice to edit in. If one wants to email or display on a website an image, you would use the ‘Save for Web’ feature which will drastically reduce the file size and offers choices of jpg, gif etc for saving.
The large file size discrepancy you saw could have been the difference of
comparing a version which was open on your computer versus just looking at a file size as reported in your browser for example. Of course, the unopened one is compressed and the open one not.
I suggest a great site for you to check out. Wayne clearly explains many
concepts which need be understood to have the most satisfiying fun with digital image editing.
<http://scantips.com>

Nancy
J
jhjl1
Oct 24, 2003
So for I have had better results with C1 (only $29.00) software for RAW conversion, it offers 2.5 stops either way on exposure compensation. I usually do exposure comp and white balance prior to converting. Remember that your original RAW file is not changed. I then make all other corrections in Elements, Photoshop or PSP. Personally I have had more success with C1 for exposure compensation. I am new to the RAW format as my old camera only shot in JPEG so this is in the experimental stages as for as workflow goes. From what information I have seen the new Photoshop will have an advanced RAW converter built in that will probably render this discussion pointless for all practical purposes. Now to convince my lovely wife I need the new Photoshop to go with my new camera.


Have A Nice Day,
jwh 🙂
My Pictures
http://www.pbase.com/myeyesview

wrote in message
James, what advantage do you see in making the exposure
corrections before
converting from RAW to TIFF? Could you achieve the same or
better
corrections with Elements? I haven’t tried corrections to my
Canon RAW
Elements with either Canon software (miserable program!) or
BreezeBrowser
(third-party conversion program, pretty nice) because I
thought what was
available in Elements was more sophisticated. Your guidance
would be
appreciated!

Chuck

IW
ID_Williams
Oct 24, 2003
Chuck,

I have used RAW format on my G5 and do like the versatility it has for exposure corrections. However, the time it takes to convert from RAW and do the alterations is prohibitive (I’m talking hundreds of images from 3 week trips). As such, I just extract the images from my G5 as .jpgs. The canon programs are also not that great and do not operate on a consistent level.

I did a few trial tests and I could not really "see" any great difference between images extracted as a RAW (and converted) or a .jpg (and converted).

Do you believe it really makes a HUGE (make or break) difference? Iain
J
jhjl1
Oct 24, 2003
Hello Iain, I realize this was directed to Chuck but I thought I would throw in my 2 cents. If you nail the exposure perfectly every time you will not notice a huge difference. If you miss a few of them as I do you have a much better chance of salvaging the shot.


Have A Nice Day,
jwh 🙂
My Pictures
http://www.pbase.com/myeyesview

wrote in message
Chuck,

I have used RAW format on my G5 and do like the versatility it
has for exposure corrections. However, the time it takes to convert from RAW and do the alterations is prohibitive (I’m talking hundreds of images from 3 week trips). As such, I just extract the images from my G5 as .jpgs. The canon programs are also not that great and do not operate on a consistent level.
I did a few trial tests and I could not really "see" any great
difference between images extracted as a RAW (and converted) or a ..jpg (and converted).
Do you believe it really makes a HUGE (make or break)
difference? Iain
IW
ID_Williams
Oct 24, 2003
Thanks for the input. It sounds as if this new program you mentioned maybe the way to go. It will be great to alter RAW using adobe rather than messing about with Canon programs.

From what you say it is better to alter the white balance and exposure in the RAW format rather than do it in elements. Is this correct?? Iain
J
jhjl1
Oct 24, 2003
I am saying it works better for me. Many people in this forum have more experience than I do with Elements and Photoshop and may feel differently. I have used PSP for a couple of years and am very comfortable with it but I still prefer doing exposure and white balance prior to converting the RAW file. If the rumors are true the new Photoshop is going to be the way to go for RAW. I have heard that it is much improved over the plugin that they now sale.


Have A Nice Day,
jwh 🙂
My Pictures
http://www.pbase.com/myeyesview

wrote in message
Thanks for the input. It sounds as if this new program you
mentioned maybe the way to go. It will be great to alter RAW using adobe rather than messing about with Canon programs.
From what you say it is better to alter the white balance and
exposure in the RAW format rather than do it in elements. Is this correct?? Iain
IW
ID_Williams
Oct 24, 2003
Cheers………..Iain
CS
Chuck_Snyder
Oct 24, 2003
James, thanks – I’ll check out the program you cited!
SS
Susan_S.
Oct 24, 2003
Because of the limitations on the RAW conversion in the Canon software – it allows very limited manipulation and is slooooooooooow – I’ve also stuck to jpg with my G3. The only exceptions are when I’m unsure about the correct white balance to use as the adjustment of white balance corrections is definitely superior done in RAW. The Canon software doesn’t really seem to have enough control over the exposure latitude to make it worthwhile. As I’m on a Mac and I’ve already exceeded my digital imaging and computer budgets for the year my options for other RAW conversion software are limited.

Susan S.
IW
ID_Williams
Oct 24, 2003
Hi Susan,

I agree with everything you have stated. It would be nice to be able to convert RAW quickly, but the canon software does not seem to want to do this! Somebody mentioned earlier on that the new photoshop will have batch RAW conversion. This sounds promising. Iain
SS
Susan_S.
Oct 24, 2003
Iain – Yes the new version of PS looks extremely promising. A lot of the new features seem aimed at digital photographers rather than graphics users. But I imagine I’d have to upgrade my computer OS to run it (haven’t checked out the requirements yet, but I presume it will require Mac OS 10.2 or 10.3 and I’m not quite there yet!) and I’m still not sure whether my machine will cope. And I’m already overbudget this year, and I’m hearing a Canon 300D calling my name….

Susan S.
IW
ID_Williams
Oct 24, 2003
Yes I know the story only too well………..

It never seems to end. Thanks goodness houses and cars have longer operational lives…..Iain

Master Retouching Hair

Learn how to rescue details, remove flyaways, add volume, and enhance the definition of hair in any photo. We break down every tool and technique in Photoshop to get picture-perfect hair, every time.

Related Discussion Topics

Nice and short text about related topics in discussion sections