what file size to shoot: large, medium or small

[amadeo]

i am new to dslr and shoot mostly Large size files, but they are huge to save on a HD and wish to know what to expect from each file size,large, medium and small. can u make enlargments from a small size file?

[Dave Humphries]

Hi amadeo,

This is difficult to answer without knowing your expectations, your camera and what format file we are talking about.

I'll describe what I have so you know what to expect.
I have a 6MP camera for which I use the 'Fine' or highest quality setting for jpg files, this produces a files between 2.75 and 3.2MB in size for my 2848 x 2136 pixels. On a 2GB memroy card that's about 680 pictures. However, if I shoot RAW, as I often do these days for a variety of reasons, the files are about 13MB each, so the capacity drops to 150 shots before the card is full.

There are two ways to squeeze more capacity with jpg; reduce the quality by selecting something like 'Normal' rather than 'Fine', or you can reduce the number of pixels saved. You could, on some cameras, shoot at 640 x 480 and have thousands of pictures on a card, but I wouldn't recommend it as you guessed right, these will not print large at all.

Memory is cheap, so why compromise on size or quality?

I suspect most people shoot at the max. resolution because you never know when you're going to shoot THE picture that you might want as say, a 44 by 22 inch canvas for hanging on your wall. But if you shot it at 1600 x 1200 (equivalent to 2MP), what's the point in having a DSLR that can do much better than that?

Hope that helps,

[Mossy]

I tend to shoot RAW, so I can twiddle the white balance and things. Yeah, the files are big and are irritating to store, but hard drives are cheap really and £80 for 500Mb or 1Tb drive is nothing compared to what you're spending in terms of gear.

If it's really that much of a problem for you, then perhaps you could try shooting some shots in different sizes and see if you think they're okay?

[Dom Ciancibelli]

i am new to dslr and shoot mostly Large size files, but they are huge to save on a HD and wish to know what to expect from each file size,large, medium and small. can u make enlargments from a small size file?

Amadeo,
The pros will tell you to shoot RAW for post processing capabilities and always shoot the largest file size that you can. If you will be printing from a 6 mp cam the largest file will get you a bit over an 8X10 print. The lowest ppi for a quality print would be sent to your printer at 240 ppi. 300 ppi is recommended for most files for most printers. Hope this helps out!
Dominc

[victorlglass]

Here's the rule of thumb.

1. If you can always shoot the largest size file for your camera. Today's low cost per megabyte for both SD cards and hard drives leaves no excuse not to shoot the largest file possible.

1a. Always shoot RAW (versus JPG) if the image will have any value to you. If you are unfamiliar with RAW files and their processing, search the internet.

2. Technically the size of the file should be determined by the output desired. If you are absolutely sure that the image will ONLY be used on the web, then you can shoot a small JPG. The problem is that if you later decide that you want to print the image at anything larger than, say, 4" x 4", you're sunk. That's why it's always a good idea to cature the largest sized file that you can.

As an after thought, the real problem with capturing and then processing very large files is one's computer. You gotta have a relatively fast CPU and enought memory. So, if you're ever in the market for a new computer, I advise that you get the fastest CPU and the largest amount of memory. You can always add disk space incrementally, and it's really cheap. Another thing. Get a video card that can has adjustments for RGB color; if you're serious about color management you'll need to calibrate your monitor.

[cav]

This is an interesting question.
I always shoot for maximum quality.

[The Blue Boy]

amadeo, welcome.

This is a question that depends on your intentions for output. Dave pretty much summed it up. I'd agree to a certain extent with the other posts.

Could you give us some more info; Camera? System? (Computer, OS, Limitations?)

[Bill44]

Shoot Raw and big. Nothing worse than thinking "It is only a family gathering and I'll just shoot medium Jpeg small", then you snag a shot of a favoured Aunt and she wants an A4 with all the spots and blemishes removed.

[Dave Humphries]

but they are huge to save on a HD

Amadeo, another thought:
It may also depend what software you are using, if I open a file in PS Elements and have the Save As dialog default to .psd or .tif, even a 3MB jpg can suddenly become a 30MB+ file, is this the problem with HD space?

With a bit more info, we can help more.

Regards,

[Colin Southern]

i am new to dslr and shoot mostly Large size files, but they are huge to save on a HD and wish to know what to expect from each file size,large, medium and small. can u make enlargments from a small size file?

Hi Amadeo,

Lots of good advice above - so I'll just summarise a couple of points quickly ...

1. If your camera is set to capture the most information (biggest file size), it's easy to reduce it to something smaller - you just can't so the other way. So "largest always give you the most options".

2. "How big you can print" depends on viewing distance. For photographers the minimum viewing distance is limited only by the length of their noses (thus they need resolutions of at least 240 - 300 ppi) - but for everyone else it's from a reasonable distance - and our eyes just can't resolve high resolutions (even with a magnifying glass) - so resolutions in the 100 to 180 ppi are just fine) (most online images display at between 70 and 100 ppi, and look just fine).

So the best advice that I can thing of is simply do a bit of testing - take a few shots at various quality settings - and have them printed at various sizes - and see what you're happy with

[Blazing fire]

I tend to shoot RAW, so I can twiddle the white balance and things. Yeah, the files are big and are irritating to store, but hard drives are cheap really and £80 for 500Mb or 1Tb drive is nothing compared to what you're spending in terms of gear.

If it's really that much of a problem for you, then perhaps you could try shooting some shots in different sizes and see if you think they're okay?

Do correct me if I'm wrong. The main advantage of RAW is to be able to do lots of post processing and repeated saving without any loss of quality. JPEG on the other hand, is a compressed lossy format so each time it is saved the quality is reduced.

So once you've finalised the image, convert it to the highest quality JPEG and save it. This vastly reduces space. As for the quality of RAW vs highest qualiyt JPEG, I'll refer you to the forum's very one tutorials: https://www.cambridgeincolour.com/tu...imagetypes.htm

Scroll down to this area

Choose Compression Quality:   	 100%  	 80%  	 60%  	 30%  	 10%
			
  	ORIGINAL IMAGE 	COMPRESSED IMAGE

I think I'm more or less correct as the page says

* Only save an image using a lossy compression once all other image editing has been completed, since many image manipulations can amplify compression artifacts.
* Avoid compressing a file multiple times, since compression artifacts may accumulate and progressively degrade the image. For such cases, the JPEG algorithm will also produce larger and larger files at the same compression level.
* Ensure that image noise levels are as low as possible, since this will produce dramatically smaller JPEG files.

[Colin Southern]

Do correct me if I'm wrong.

You're wrong!

Nah - just kidding Seriously, what you say is quite right - but it's one of those "horses for courses"type things; many consider that processing of good images are never complete, they're only "abandoned" at some point. If you get to a point where your only copy of the image is a high-quality JPEG then that's all you have to work with in future - whether that's adequate or not depends on what the intended purpose is, and what the photographer wants. In my case - being primarily a landscape shooter - I shoot dozens to hundreds of frames for a given sunset or sunrise - pick the best one (and only one) and process it from there. From that point I'm left with 1 RAW, 1 PSD, and a collection of bulk DNG files that don't consume too much space (they typically fit on a backup DVD). In contrast a collegue shoots weddings - and if he only processed 1 "keeper" out of one hundred shots then he'd be in big trouble - so he needs to retain more keepers, but they don't need to be anywhere near the same size/quality as what I'm shooting (his max size is typically a 6 x 4 whereas mine is typically 44 x 22").

So the "best approach" can and does vary from person to person. Personally, I agree with the camp that says "storage is cheap" and as such, never shoot or store as JPG (the only exception being uploads to the website for online display).

The other "mantra' that I'm not convinced about is the statement I'm always hearing about JPG images degrading each time they're saved; whereas it's true that a LOT of information is thrown away the first time that a file is saved as a JPG, when it's subject to re-saving - and the same compression algorithims are used - I suspect that it would end up not making any further changes to most areas since it would already have been optimised on the first pass (a bit like how a zipped file doesn't keep getting smaller if you try to zip the zipped file). Haven't done any testing to prove either way, but just a suspicion I have.

[nobby]

Until about 18 months ago I always shot in Jpeg until I read about RAW, then my whole outlook changed, I now shoot in RAW only, this gives better manipulation of the image within the PP and is non-destructive, what I do is a 3 part process. Save the RAW files onto a DVD and external hard drive. Convert to a Tiff/Jpeg and lastly if I wish to post onto the Web I will do a copy. As said previously memory is cheap these days and also purpose built websites for photography are available

[Blazing fire]

mine is typically 44 x 22"

That's huge!

If you get to a point where your only copy of the image is a high-quality JPEG then that's all you have to work with in future - whether that's adequate or not depends on what the intended purpose is, and what the photographer wants.

Very true. Do you mind taking a look at the link I provided? I can't, for the life of me, differentiate the difference between the original (whatever that is) vs 100% JPEG. I suspect it's because I don't have a calibrated 8bit IPS monitor . Or perhaps the lens/sensor/subject is a limiting factor.

The other "mantra' that I'm not convinced about is the statement I'm always hearing about JPG images degrading each time they're saved; whereas it's true that a LOT of information is thrown away the first time that a file is saved as a JPG, when it's subject to re-saving - and the same compression algorithims are used - I suspect that it would end up not making any further changes to most areas since it would already have been optimised on the first pass (a bit like how a zipped file doesn't keep getting smaller if you try to zip the zipped file). Haven't done any testing to prove either way, but just a suspicion I have.

Interesting prospect. I have not thought of that before.

And yes, storage is getting quite cheap nowadays... thankfully!

[Dave Humphries]

Hi Blazing fire,

I think the point is that at high qualities, you may not see a difference. I note the original (LH) pic is a png, where as the other (RH) is jpg with a number corresponding to which ever % quality you have selected.

I think the aim of that pair of images is to hover the mouse over the 100% or 80% or 60% and look for changes in the right hand pic. I cannot see any between 100 and 80%, minimal between 80 and 60%, then it gets worse betwen the lower %s as you'd expect.

To clarify, once a RAW file gets into say photoshop, or any editor with layers, it won't be saved back as the RAW format (it can't), so if you break the session to save, it will have to be another lossless format; usually psd or tif. Then as you say, the final save for print or web can be a good jpg. Incidentally, in Elements, and I think most other editors, rather than quality in %, you get a scale of 1 to 12, I save at 10, which is probably still overdoing it, since above 10 the only thing that seems to improve is sales of Hard Disks

Colin,

When testing (if you do), I believe what you do (before re-saving) can have a profound effect on the results.

As I recall jpgs work in 8 x 8 pixel blocks, most image editors these days know better than to change one of these blocks if they don't have to*. What I suspect this means is that if you have an image and crop 6 pixels off the right and/or bottom edges, you'll likely only see any quality reduction in those places. However, if you take anything that isn't a multiple of 8 off the left hand side or top. say 4 pixels, it will be forced to re-sample the whole image into a new set of 8 x 8 blocks and that's when you'll likely see an overall quality hit.

* this is why repeated open-save-close-open-save-close without any changes probably won't show any problems (or change of file size), but I haven't tried it myself.

It is the same with 90/180/270 degree rotation; if it can be done within the confines of 8 x 8 blocks, it can be lossless, but if your picture size isn't divisible by 8 on both width and height, when you rotate (e.g. landscape to portrait), you'll probably be warned this will cause irreversible quality reduction.

Now these quality hits will be small if you'e working around 80% (or 10) quality, but probably horrid if much less than that; they will be more noticeable on diagonals and curves, and on text (like an embedded copyright).

I also suspect this may be why when you attempt to crop a jpg, it always goes in big chunks, (8 pixels) in order to preserve quality, unless you zoom in sufficiently to force it into smaller increments.
Another thing I suspect clever image editors do is that even if you save repeatedly during jpg workflow, as long as you don't close and re-open the file, you will not degrade on each save, since the image remains in the editor's native, lossless data format in RAM.

The above is based on a little knowledge (always a dangerous thing!) and my observations and experiences.
No warranty as to accuracy is given or implied

Discuss....

Cheers,

[Colin Southern]

That's huge!

Nah - that's normal; we do much bigger than that

Very true. Do you mind taking a look at the link I provided? I can't, for the life of me, differentiate the difference between the original (whatever that is) vs 100% JPEG. I suspect it's because I don't have a calibrated 8bit IPS monitor . Or perhaps the lens/sensor/subject is a limiting factor.

Would love to, but can't right now as I'm nowhere near a profiled monitor. Keep this in mind though that for all intents and purposes the quality of a maxed-out JPEG will be indistinguishable from an equivalent TIFF or PSD (you might see a small difference at 200%, but you won't see anything in a real-world print). JPEGs are great in that they let you decide where in the quality -v- size tradeoff you want to position yourself; in my opinion the main limitations are in other areas (like the inability to handle layers or 16 bit colour depths) (which can directly impact on further editing).

I think that many people have it in their minds that JPEGs are somewhat of an illegitimate child to the likes of TIFF and PSD formats, but in reality they're just another tool that can be both used or abused.