Digital cameras

[steve threlfall]

I need some advice please guys. I want to get a decent digital camera but i dont really know what to look for.

Im after something thats small and good looking like a Minolta with decent picture quality- doesnt have to be incredible or anything.

Im looking to spend £100 ish, can go a bit higher if its worth spending more. Any ideas

[Skii]

If you want to access your pictures easily - don't get a Canon

[Saracen]

You could perhaps do worse than also ask this at www.digi-darkroom.com. You'll spot some familiar names () over there.

I haven't looked at any cameras in this bracket recently so hesitate to give model-specifc comments, so this is general stuff.

Don't get TOO taken up by resolution claims. Ignore interpolated resolution claims completely (with the possible exception of Fuji claims). It is optical resolution that matters. If you want me to explain why Fuji is different, either check it out at the Digital Darkroom or ask here and I'll explain.

Next, how big will you want to print images? Because THAT is what determines how much resolution you need. Unless you are after exhibition standard prints, assume you'll need about 200dpi when you print. That means if you want to print at 6"x4" (typical high-street lab size), you'll need 1200x800 pixels in the image (it's simple multiplication). Each pixel requires 3 bytes, so 1200x800 pixels is 2,880,800 pixels, which is roughly 2.75 megapixel. Cameras need some extra pixels for control information, so you're looking at about 3 Megapixel to get optimum print quality at that size.

If you want to print much larger, OR want to print small sections of an image at 6x4 (i.e. enlarging and selectively printing), then increase the resolution of the camera from 3 MegaPixel accordingly.

If, however, that is all you want, then by going for anything higher than that, all you do is increase price, increase file write times, and increase the storage capacity you'll need to buy.

Don't assume that all 3 MegaPixel cameras provide equal quality though, because they don't. Lens quality maes a difference, and so does the qulaity of the censor and support circuitry. Cheap cameras may well have poorer components that a dearer one, and that will lead to a higher noise level in the circuitry and that leads to loss of shadow detail. On the other hand, with brand names, you do tend to pay a premium for the name.

If you want optimum quality for the money, you really have to either do your own tests on models you're thinking about, or take advice from people that have. Bear in mind that it can be misleading to place too much credence on the comments from someone that only has the one camera, since though they may be happy with the output, they may not have anything to directly compare it too.


Note: before anyone takes the fact that I've pointed people at the Digital Darkroom (my forums) and uses that as a precedent to promote their own forums here, I have explicit permission from David to do so. In fact, it was his idea to do so. Thanks, Dave.

[dustycantpost]

amazon pentax 33l

[Skii]

Sow how is Fuli intepopopalation different then Saracen - I'm curious now

[Saracen]

Fuji use a different design if sensor to everybody else. The pixel arrangement is different. The actual pixels in most cameras only see one colour, be it red, green or blue. Each pixel in a photo therefore is a combination of the data from several (four in fact) adjacent pixels (except for cameras based on the Foveon chip), two of which will always be green, one red and one blue. In conventional CCD's, these pixels are arranged in rows, and each image pixel consists of data from two side-by-side pixels in one row, and two relative pixels in the row below.

In Fuji's SuperCCD, however, the pixel pattern is different. The pixels are octagonal in shape, and the pixels (still monochrome) used are therefore arranged in a diagonal pattern, not a horizontal and vertical one.

Fuji's claim is that their pattern reduces the horizontal and vertical distance between pixels, at the expense of increasing the diagonal distance. As the eye is better at detecting vertical and horizontal anomalies than it is diagonal ones, the EFFECT on the eye is to appear to be better resolution. Ultimately, technology aside, the benefit of increased resolution (up to a point) is finer detail and if Fuji can trick the eye like this, then they have achieved a real-world effect and not just a marketing con.

Generally, though, interpolated resolution claims are just a marketing con. All "interpolation" is is marketing techno-babble for "guess". Software mathematiclly "guesses" what a given pixel, that the sensor didn't actually capture, should be by analysing adjacent pixels.

A simplistic example would be if two adjancent pixels were white-black to "interpolate" this to white-midgrey-black, thereby achieving an "interpolated resolution increase of 50%. The actual maths is obviously a lot more complex than that, but you get the idea.

Of course, there's nothing to suggest that this would actually have been the data that would have been captured had the resolution really been that much higher. It could have been white-white-black, white-black-black or, for all we know, white-red-black.

Any half-decent piece of image-editing software (Photoshop, PhotoImpact, Paint Shop Pro, et. al.) has routines built-in for increasing resolution in exactly this way, so why bother to pay for it in a camera? A purist will argue that doing it in-camera means it can be done on raw image capture data before any post-processing is done by the camera, and there might be a very small grain of truth in that, but in practical terms, "interpolated" resolution claims are just a way for the manufacturer to make you think you're getting something better than you are.

Except Fuji.

My real-world tests suggest that Fuji are on to something. The image detail from their SuperCCD cameras does tend to be better than I would expect from a camera of the actual optical resolution of their models, though not by as much as Fuji claim. Fuji tend to double the optical resolution to give their effective resolution, so a 3MP optical resolution ends up as a 6MP effective. Personally, I'd say it's more like 50% improvement. A Fuji 3MP optical resolution equates to more like 4.5MP (maybe 5MP) from a camera using the conventional rectangular pattern.

If you want more detail than that, take a look at this, where you'll find a lengthy exposition on all sorts of aspects of resolution, including why you print at 200dpi, maybe 300 dpi, for optimum results on a 1440dpi (or 2880 dpi, or whatever) inkjet printer.

Resolution is one of the most badly misunderstood aspects of digital photography, probably second only to colour matching.

[Skii]

Interesting stuff - cheers Saracen <strokes Fuji camera >

[Howard]

Interesting read 'Cen

*strokes Olympus camera... Made by the experts... Not some Supermarket brand rubbish

[joshwa]

for a £100 camera that's small you're probably looking at the :

Minolta X20 (2mp, 3x opt, £105 cameras2u.com)
Sony DSC-U30 (2mp, no optical zoom, £103 - ebuyer.com)

unless you can find some other cameras perhaps end of line that fit your bill. of those i'd go for the minolta x20.

it is worth sticking to the main brands: canon, olympus, fuji, nikon (i've seen the nikon 2100 in jessops for about £99 in liverpool), minolta / konica etc. and number of megapixels isn't very important really, especially if a "generic" 4mp for £99 produces pants colour, whereas a 2mp minolta produces good colour.

edit - morgan computers have some good prices too if you wanna stretch yourself, but remember you do have to buy memory / in some cases rechargable batteries as well, as the included memory is normally pants:

http://www.morgancomputers.co.uk/sho...CategoryID=119

Fuji F410 £129 (3mp/3x opt)

http://www.morgancomputers.co.uk/sho...CategoryID=179

Konica KD410Z £140 (4mp/3x opt)

[TeePee]

I'd spend a little more and go for a fuji finepix s3000 for #139 from www.7dayshop.com

[Tom]

or if you can't afford to go over £100

http://www.7dayshop.com/catalog/prod...ducts_id=97118

Fuji A330

[steve threlfall]

Thanks a lot for the info and links chaps

I only really need something with decent picture quality as my untrained eyes wont be able to tell the difference anyway. It has to be really small, like the Pentax Optio S (though thats a little too pricey at the moment) or a canno ixus. Minoltas cameras seem to fit the bill perfectly so i'l have a root around.

Skii what problems have you had with your cannon? my dads got a 3.2 ixus 2 i think it is and hes had no problems- though he is a bit obsessed with digi cams

[Lowe]

What about this?

http://www.dixons.co.uk/martprd/stor...:28&sku=951325

5mp for 150 quid? Seems too good to be true! Any thoughts on this one Sara?

[Rave]

Next, how big will you want to print images? Because THAT is what determines how much resolution you need. Unless you are after exhibition standard prints, assume you'll need about 200dpi when you print. That means if you want to print at 6"x4" (typcial high-street lab size), you'll need 1200x800 pixels in the image (it's simple multiplication). Each pixel requires 3 bytes, so 1200x800 pixels is 2,880,800 pixels, which is roughly 2.75 megapixel. Cameras need some extra pixels for control information, so you're looking at about 3 Megapixel to get optimum print quality at that size.

Right, once again I'm 'cruising for a bruising' by arguing with a man who has reviewed cameras professionally and administrates a digital photography forum, but that's a bit of a misleading explanation. To cut and paste your diagram from your thread on the Digital Darkroom forums:



GRGRGRGRGRGR
BGBGBGBGBGBG
GRGRGRGRGRGR
BGBGBGBGBGBG
GRGRGRGRGRGR
BGBGBGBGBGBG
(CBA to go through and colour it in again ) a traditional CCD sensor arranges its pixels into square grids containing one red, one blue and two green pixels (or, more precisely, pixels which are sensitive only to blue, green and red light). So, a 3mp sensor will have roughly 750,000 each of blue and red sensitive pixels and 1.5m green sensitive pixels. There's a good reason why there are twice as many green pixels BTW, it's because in practice most of the light from the sun (and from a lot of artificial light sources too) is in the green range, and consequently our eyes are best at detecting subtle differences in green light, so it makes sense to ensure the CCD is most accurate in the green range.

So far so good, but the thing is that a 3mp camera actualy outputs an image containing 3 million pixels and each of those pixels contains a discrete red, green and blue value, usually in 8 bit precision for each channel. The camera actually has to do a calculation to map a value for the other two colours onto the value for each individual coloured sensor on the CCD. I guess it does this in a similar way to interpolation.

So, the point is that for a 6x4 print at 200dpi, you actually only need about a 1.3mp camera. A 2.1mp camera will give you nearly 300dpi and will look a bit sharper, but 3mp is basically overkill for 6x4 prints.

My real-world tests suggest that Fuji are on to something. The image detail from their SuperCCD cameras does tend to be better than I would expect from a camera of the actual optical resolution of their models, though not by as much as Fuji claim. Fuji tend to double the optical resolution to give their effective resolution, so a 3MP optical resolution ends up as a 6MP effective. Personally, I'd say it's more like 50% improvement. A Fuji 3MP optical resolution equates to more like 4.5MP (maybe 5MP) from a camera using the conventional rectangular pattern.

Well, not only do they quote double the resolution, they actually interpolate the output image to double the resolution- they have to. The octagonal pixels are arranged in diagonal lines; however no image file format will allow you to store an image with the pixels arranged diagonally so Fuji have to 'fill in the gaps' to give a 'normal' output file. Time for my attempt at a diagram:

o-o-o-o
-o-o-o-
o-o-o-o <--- octagonal orrangement of pixels on CCD (hyphen = gap)
-o-o-o-

ooooooo
ooooooo
ooooooo <--- output file with gaps filled in by camera
ooooooo

I agree with your comments about it being a 50% improvement, but what you actually have is a 6mp file with equivalent sharpness to a 4.5mp file from a normal camera- consequently you pay a penalty in file sizes, although with flash memory so dirt cheap now this is less of a concern than it once was. Ironically, Fuji claim that the octagonal shape of the pixels allows them to be packed closer together which leads to greater sensitivity and in theory lower noise; however in my experience the extra post processing that's necesary makes the images from Fuji cameras some of the noisiest around.

Sorry to crap your thread with my pontificating Steve.

Rich :¬)

[Skii]

Skii what problems have you had with your cannon? my dads got a 3.2 ixus 2 i think it is and hes had no problems- though he is a bit obsessed with digi cams

Doesn't show up as a removeable disk in 'my computer' m8, so unless you use the 'easy to use' software to download the images there is no way of accessing the images off the camera, the only other way around it is to take the compactflash card out and use a card reader.

I've always never used the software that comes with cameras, I prefer to go straight into the camera (showing as an additional storage device next to your hard disk) and drag and drop them onto my desktop, I can then chose to open them with photoshop if needs be. I can do that no problem with my Fuji, but not with my Sister-in-laws new Canon.

Very frustrating.

[Stubzz]

So i'd be advised to get myself an external flash card reader then. Got a Cannon camera being delivered some time this week.
While we're on the subject. The camera I'm getting doesn't have any optical zoom, only digital. onsidering I'm only gonna use it for simple pictures am I likly to nitice the difference much, I gather digital zoon just 'zooms' into the picture after its been taken.