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MarkW
13-07-2008, 10:43am
I am currently keeping a lot of my image files as either RAW (if they wer taken that way) or in 16 bit TIFF (uncompressed) but finding that a 15Mb image file when coverted to uncompressed TIFF is about 4 times larger - 60Mb :eek: . At these sizes the images are rapidly draining my storage resources even though I have only just dedicated a Terabyte external HDD just for some of my most recent photography.

I realise that there are compressions available for TIFF but I don't know enough about them to risk subjecting the images to the process. I really do want to maintain a 16 bit quality in the images.

What format do most people keep their images in?

Please note - before you say JPEG, I wont use any compression format that will create a loss of image quality and JPEG does just that. So if its JPEG that you use that fine but no need for a reply. :)

brindyman
13-07-2008, 10:56am
Please note - before you say JPEG, I wont use any compression format that will create a loss of image quality and JPEG does just that. So if its JPEG that you use that fine but no need for a reply. :)

JPEG works by taking out bits of the picture that the naked eye wouldnt recognise hense the smaller size than something compared to a bmp or a tiff.....hense then a jpeg is a lossy format and tiff and bmp are lossess meaning they retain all their information.

Theirs nothing against storing your photos in jpeg in my opinion.......how ever if you want to print them i would also recommend printing TIFF files as they seem to come out better on paper.

Hope that helps

Ben

MarkW
13-07-2008, 11:07am
JPEG works by taking out bits of the picture that the naked eye wouldnt recognise hense the smaller size than something compared to a bmp or a tiff.....hense then a jpeg is a lossy format and tiff and bmp are lossess meaning they retain all their information.

Theirs nothing against storing your photos in jpeg in my opinion.......how ever if you want to print them i would also recommend printing TIFF files as they seem to come out better on paper.

Hope that helps

Ben

Ben
JPEG takes out the transitional bits ie where it originally was 256 graduations of colour change this is now down to 16 changes (I think - 8 bit vs 16 bit) and whilst you might get away with it on a screen, my only purpose of taking images is to end up with an album full of "photos".

What is worse is every time I make an alteration, the JPEG image is recompressed thus loosing more and more data each time. No JPEG is not a consideration at any time.

You can always make an extra JPEG image (save as type) if you need that format say for the net or distribution to others after you finish making alterations to the original but you need to keep the original in the best possible format available and thats not JPEG.

Desertraptor
13-07-2008, 11:09am
The eye can detect many more shades than your screen can display. So why display them?
I used to process TIFF and save then also save a copy as jpeg for the net. Now though I just save the published image as a jpeg and keep all RAWS on dvd

brindyman
13-07-2008, 11:31am
The eye can detect many more shades than your screen can display. So why display them?
I used to process TIFF and save then also save a copy as jpeg for the net. Now though I just save the published image as a jpeg and keep all RAWS on dvd

thats not a bad idea :) all be putting them on blu ray soon :D

the way hard drives are going now they are getting so cheap its ridiculous you can pick up a good 500 gig hard drive for like $120

Desertraptor
13-07-2008, 12:25pm
Pioneer Blu-Ray at MSY now $309 :)

Seesee
13-07-2008, 5:18pm
My percieved extra good pix { rare :rolleyes: } I keep in both full resolution jpeg and RAW fgor later processing if I want to, anything else I just keep in jpeg at full resolution. Tiff as mentioned are huge files !!!, not necesary I think and as a hobbyist photographer I need to do nothing more. Despite storage being cheap I dont want squillions of pictures to have to sort through anyway, so now I delete most of mine now except the best.

arthurking83
13-07-2008, 7:27pm
I only keep the RAW files.

My reasoning:
If I want TIFF's for printing, I'd prefer to convert a batch of those RAW images(for printing) into TIFF's for that purpose only, and then delete them off the PC as soon as the images have been printed.
Have yet to print any images though.
As I only process my NEF's and keep them that way to the end.. they take up(as Mark says.. 1/4 of the space of TIFF's)

I have a stash of jpgs used for upload purposes, and also a few megs of images I specifically placed into a folder that I upload to my personal gallery... but they take up only a few megs.. and I clean them all out every now and then.

So far I'm still surviving on about 110 Gigs, with about 70G's remaining on that drive.
NEF seems to me to be a great file type for storage(for now).

Have you looked into DNG?
I don't know about about it though... and I remember it was supposed to be a reasonable file type(if you work with Adobe software) :confused:
I think this is supposed to have a level of lossless compression built in?
Someone with more knowledge may know?

MarkW
14-07-2008, 11:03am
Thanks Arthur

I had thought of DNG but as I only use CS2 (my only Adobe program) as a last resort, that format isn't one that I come across too often.

Maybe I should just keep everything in RAW (I wonder if NX2 can get a file back to RAW from TIFF :rolleyes: ). At least NX can do a reasonable job of PP an image without change to another format unlike almost all of the image processors that I know of.

cwphoto
14-07-2008, 2:05pm
Thanks Arthur

I had thought of DNG but as I only use CS2 (my only Adobe program) as a last resort, that format isn't one that I come across too often.

Maybe I should just keep everything in RAW (I wonder if NX2 can get a file back to RAW from TIFF :rolleyes: ). At least NX can do a reasonable job of PP an image without change to another format unlike almost all of the image processors that I know of.

I just keep mine in RAW until I need to use them. Then I create a temporary image in either TIFF (rarely) or JPEG (mostly) depending on needs.

There's no point keeping all these TIFFs around unless they are a composite image etc.

Helen S
14-07-2008, 2:43pm
Same here, all images are kept in RAW, except for a few mb of JPEGs for uploading to the web and a dozen or so TIFFs that have been a popular selling image.

MarkW
14-07-2008, 4:39pm
Hi Helen
A delightful surprise to see you back. I havent had a large amount of time for AP (or any other site FTM) since getting back from OS - too many images to deal with has taken a very large chunk out of my spare time, so I may have missed your return.

Sorry if this message is a little belated - but nice to see you here

Helen S
14-07-2008, 6:48pm
Thankyou so much Mark :) ...a bit of an explanation can be found HERE (http://www.ausphotography.net.au/forum/showthread.php?t=14305).