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Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Fri Mar 21st, 2008 at 04:26:22 AM EST
Photobucket

Taken in Mumbles in Swansea last weekend.  I had an ND grad filter to darken the sky, and two solid 4 ND filters to slow the shutter speed to catch some wave movement.

I wish I'd had my wide angle lens with me, but it was a spur of the moment trip since I was already in Swansea working.  It's not an amazing photo but it shows some progress for me.

Photobucket

This photo was done with the same set up - both using a sturdy manfrotto tripod.  I played about with the RAW files a little to bring out the sand a little more but I still find both pictures a little dull overall.  It wasn't so obvious in photoshop last night but the second one needs brightening.

Better res photos can be seen by clicking on the photos.  Any advice on how best to manipulate the RAW files to improve the colours etc would be appreciated.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 04:40:52 AM EST
[ Parent ]
Were those the Cokin ND filters? As far as I recall, they're not quite true ND - they're ever so slightly red. Have you tried messing with the colour balance?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 04:42:55 AM EST
[ Parent ]
Yes Cokin. I did mess with the colour balance. I tried to bring out the red a little more for the sand in the RAW file but I was just playing. I don't actually know what I am doing.  

I find that when I manipulate the colours for a bit, I forget what it ought to look like and loose my judgement on whether or not the manipulation has become too obvious and unreal.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 04:46:47 AM EST
[ Parent ]
Here is a deliberate wonky colour experiment. I wanted more of a sepia look to it though.

Photobucket

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:03:42 AM EST
[ Parent ]
this is totally classic, fantastic composition, with a huge pull, perfectly enhanced by the sky. i don't know if you tweaked it, if you did, superb job, if not....pure magic!

the wrought iron and weathered boardwalk planks really work well together and the purple highlights in the sky are gorgeous.

stunning, i'd give you a ten if i could. it's great to see your style growing over the months, what an eye you have...

~"When an inner situation is not made conscious, it appears outside as fate." Karl Jung~

by melo (melometa4(at)gmail.com) on Fri Mar 21st, 2008 at 08:31:11 AM EST
[ Parent ]
Thanks Melo, I tweaked the colours a little.

I am still umming and ahing over whether or not to go out with the camera today.  We've had rain and sunny spells so I may chance it. I have just cleaned all my leneses and formatted my memory cards.  I have my all weather clothing ready so I have no real excuse not to go out.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 08:45:30 AM EST
[ Parent ]
if the wind is anything like here,  you'll have tyrouble holding things straight

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Fri Mar 21st, 2008 at 10:09:08 AM EST
[ Parent ]
Yeah it was a bastard out there.  Really chilly wind, pelting rain, then sun and then snow with my breath clouding in the air - the temperature drop was in a matter of seconds. No wonder silly unprepared people get caught out by the weather in the mountains.  

I ran back to the car and the sun came out in the distance.  I didn't get any especially good photos but I'll stick a couple in here in a bit.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 02:38:32 PM EST
[ Parent ]
yesterday i took 150 + shots, there was so much going on in the sky, really 'weathering' as a friend of mine used to say.

then my camera died today, talk about the sunset effect!

it was a samsung techwin digimax S1000/kenox 10.1 mb, and i really liked it, though i hadn't got that deep into what it can do yet.

i'm uncertain whether to get another like it, or go for the 12.0 mb cameras that have come out since.

since most of what i try to capture is light effects, and i'm a complete dummy with manuals, i'd pay a bit more to have quality, but don't really need bells and whistles i probably get around to using.

any suggestions in the €2-300 range, anyone?

such a wonderful last day, though...

i had just mounted paddy today to go ride and two falcons started circling above me, quite low. i turned on the camera to grab some shots and it just lights up for a second then beeps at me, and the lens stays out.

gaah

~"When an inner situation is not made conscious, it appears outside as fate." Karl Jung~

by melo (melometa4(at)gmail.com) on Fri Mar 21st, 2008 at 12:26:20 PM EST
[ Parent ]
You're sure it's dead?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 12:29:14 PM EST
[ Parent ]
i think the beep is coming from beyond!

it's moribund, there are flickers of response, but after 2 secs it dies. and yes i tried two fresh sets of batteries.

it's odd, because the lens cap had been jamming for a couple of months, i'd have to tap it for it to fully open, then i dropped it the other day, (first time), and the lenscap worked again.

2 more days of normal life then this...

RIP

~"When an inner situation is not made conscious, it appears outside as fate." Karl Jung~

by melo (melometa4(at)gmail.com) on Fri Mar 21st, 2008 at 12:51:31 PM EST
[ Parent ]
I assume you changed the batteries.

Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Fri Mar 21st, 2008 at 12:34:40 PM EST
[ Parent ]
Just pops off the page. Nicely done In Wales.
by olivia on Sun Mar 23rd, 2008 at 06:04:58 PM EST
[ Parent ]
Thanks and hi!

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Mon Mar 24th, 2008 at 03:26:15 AM EST
[ Parent ]
Hi Olivia. I'm hoping to see some of your beautiful photos over here. Maybe even some of your rejects that don't make it to your own blog :-)

Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Mon Mar 24th, 2008 at 05:02:05 AM EST
[ Parent ]
Lately all the photos I've taken are of the big mounds of snow we've been deluged with. Here's one taken this past summer when the world was green and warm ... ;)


Click for larger

by olivia on Mon Mar 24th, 2008 at 12:07:07 PM EST
[ Parent ]
Thanks, Olivia, for making me happy!

Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Mon Mar 24th, 2008 at 01:53:08 PM EST
[ Parent ]
Very nice. The first looks almost like a painting.

Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Fri Mar 21st, 2008 at 04:44:27 AM EST
[ Parent ]
Do you mean something like this?


by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 04:49:39 AM EST
[ Parent ]
Yes! What did you do?

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 04:51:47 AM EST
[ Parent ]
Well, if you'd been paying attention in class last week, you'd have seen me muttering about histograms: in the case of these images, the histogram was compressed into the bottom 2/3s of the range. I just let Aperture's auto-colour-levels control expand it out to fill the whole range.

I also changed the tint towards the green a bit because the pink in the clouds didn't seem natural.

by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 04:57:20 AM EST
[ Parent ]
I did pay attention. I know a bit about histograms and usually refer to them directly after taking a shot, but I get confused with the RAW file manipulation in CS2 since it separates the histogram into RGB and well... y'know?

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:00:45 AM EST
[ Parent ]
Does it not give you a luminance histogram as well?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:06:42 AM EST
[ Parent ]
Is the white area the bit I need to work with?

Photobucket

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:16:27 AM EST
[ Parent ]
Not sure: I think so, but the yellow and cyan ones are confusing me.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:19:16 AM EST
[ Parent ]
Well if you're confused....

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:48:23 AM EST
[ Parent ]
The white line at the extreme right indicates that your highlights are going to pure white. If this is not a specular reflection, this might not be what you wish.

The white area under the other colors is just an indication of the proportion of black in the image.

Personally I dislike this tool since one can't tell what is really being changed. I would suggest you try to get the same corrections with the curves tool in the main area of photoshop.

There are way to achieve white balance as well as fixing the overall brightness and contrast. Unlike this tool the curve shapes give you a visual indication of what is being modified.

It takes a bit of time to master, but it is worth it, for images you want to look their best.

Policies not Politics
---- Daily Landscape

by rdf (robert.feinman@gmail.com) on Fri Mar 21st, 2008 at 09:54:50 AM EST
[ Parent ]
Using Curves you can get this:

Clicking with the middle (50% grey) eyedropper on the blue-ish hills in the distance tells Photoshop to white-balance to the opposite of blue-ish, which is this sepia, and then clicking with the white eyedropper in the brightest area, which is the cloud centre-left top. It's not quite the same as using a sepia filter or colorize.

If you try to find a more usual mid-grey you'll get a more accurate colour balance. There are auto-mask methods for finding the 50% level in a shot, but it's usually more fun to click around with the eye droppers at random to see what happens.

This is almost a photo magazine shot. You'd need an even longer exposure on the waves to make them even wispier, an even wider lens, and ideally you'd also need to take it at sunrise or sunset to make everything look dramatically pink or orange. This should be followed by even more dramatic Photoshop colour enhancement, until you get something that looks like a rather poetic episode of Star Trek, where the sky is bright pink and misty and the clouds are made of hydrogen.

I'm not suggesting any of these are a good thing, but it's the kind of style the mags seem happy to print rather a lot of.

I'd rather:

which is a slightly less familiar crop, but I think it still captures some of the essence of the scene.

by ThatBritGuy (thatbritguy (at) googlemail.com) on Fri Mar 21st, 2008 at 03:11:34 PM EST
[ Parent ]
Thanks for that. I'll have a go and see if I can reproduce something similar.  It is amazing what you can do with photoshop when you know how.  I like the alternative crop a lot too.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 03:21:16 PM EST
[ Parent ]
That's what happens when the real experts come out of the woodwork.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 03:38:21 PM EST
[ Parent ]
Lack of time has been the main reasons for not getting to grips with photoshop a bit better.  There are probably digital photography classes somewhere. I'll have to see if I can get onto one that looks at using photoshop.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 03:32:43 PM EST
[ Parent ]
I've got lots of tips on my web site and you don't have to pay a dime.

http://robertdfeinman.com/tips

Policies not Politics
---- Daily Landscape

by rdf (robert.feinman@gmail.com) on Fri Mar 21st, 2008 at 04:41:48 PM EST
[ Parent ]
Oooh!  Consider yourself paid back with happy vibes.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 04:52:45 PM EST
[ Parent ]
I prefer, as in this case, to work in Photoshop layers. What I do is make some basic assumptions about the image - what i it that I want to emphasize.

Then I make layers that emphasize these differences - such as a layer to bring out the detail in the rocky cliffs by lifting brightness just in these areas that I have selected by the magic wand. Or distinguishing between the sea/sky and the beach/rocks and making one cooler and one warmer. I used about 6 layers here and then played with the transparency of the layers - most of them just a few percent opacity. So I make raw decisions and then fine time them interactively.

The decisions are always based on telling a story that the audience will accept. The better you know the particular audience, the better you can tell the story.

IMO there is no such thing as a 'true' photograph.

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 05:14:09 PM EST
[ Parent ]
IMO there is no such thing as a 'true' photograph.

Did someone say there was?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:15:23 PM EST
[ Parent ]
No. I see your aim as to perfectly express the recorded image, whereas the recorded image is already a distortion of the original experience. Whatever you do, you will 'impose' on that distortion.

Acceptance of distortion (starting from the framing) is entirely dependent on the audience - even if the audience is you ;-)

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 05:26:55 PM EST
[ Parent ]
Which of the possible uses of "your aim" did you have in mind in that first sentence?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:37:13 PM EST
[ Parent ]
I am referring to your entirely reasonable pedagogic aim of giving people the gestural tools to ensure that a picture at least conforms to their own aims for the picture.

Art is, after all, a very precise coordination of mind + eye, plus tool and medium. Serendipity can also play a part - like Japanese calligraphy - but serendipity born of the tools, not of the mind.

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 05:50:28 PM EST
[ Parent ]

I managed to bring out some details not seen in the original ;-)

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 03:07:13 PM EST
[ Parent ]
Now, if you just drop in a Viking longboat and maybe a few Grays you'll be done.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 03:16:24 PM EST
[ Parent ]
Well I do regard raw photographs as artist's sketches - if I've experienced the event myself, I use the sketch/es as a basis for finding a visual interpretation of what I felt I saw, as opposed to what the camera saw.

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 03:34:36 PM EST
[ Parent ]
Like my failure to see any difference between drugs from outside or outside the body, I also don't see ANY difference between all manipulations of subjective experience of reality - including the original framing of the photograph.

When you frame a shot you are translating your total experience of an event, or moment in time, into a narrow channel that not only excludes all the other senses, but also excludes 95% of the spherical moment that you inhabit.

The camera, lens and image capture system that you pick up, is already an intrusion into the total reality of theat moment. If you then make a slight adjustment to contrast and colour of that image, you have already further distorted sensual 'reality'. You can add a lightning strike - that is also distortion. This addition is obvious here, since the original from which it is derived is presented also. But in another situation - sitting in a photo library? Is it real or is it not?

The key is, of course, the audience. What do they accept? How do they react? What have they seen before? Have they had a similar experience to which they can compare?

Just taking a photograph is manipulation. I don't see any difference between the moment (the sketch) and any manipulation that may come later (the work)

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 05:00:10 PM EST
[ Parent ]
Sure. I just don't feel I experience scenes in the exaggerated manner you feel you do.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:04:12 PM EST
[ Parent ]
And if you're doing art (broadly), rather than commercial work, should you be considering any audience other than yourself?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:08:16 PM EST
[ Parent ]
Well that is a whole diary ;-)

It is all art. The story depends on you if the audience is zero (just yourself), and also depends on you if the audience is one million. I don't see how the money comes into it.

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 05:22:02 PM EST
[ Parent ]
But my argument depends on your acceptance of the idea that the framing of the picture from the very start is a distortion or manipulation, let alone any manipulation that would be 'emotion recollected in tranquillity'

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 05:30:03 PM EST
[ Parent ]
Looking at the scene is a distortion and a manipulation, if mostly an unconscious one, never mind pointing a camera at it on top of that.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:34:23 PM EST
[ Parent ]
And here we enter the Russian Doll zone. I absolutely agree. The selected matrix is always a compromise.

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 05:39:46 PM EST
[ Parent ]
lol!
Ah yes, I wondered what had happened to that streak of lightning. I almost thought I had imagined it.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 03:17:36 PM EST
[ Parent ]
see any difference?

i put it into iphoto and it looked better to me already. i went to the pic by clicking on it and 'borrowed' it from there.

there's a lot of beautiful, interesting textures going on in this pic, but the light was too dull to bring out the richness of the colours, especially the warm brown of the sand.

the frozen splitsecond of the foam, for instance, and the glimpse-of-infinity in the dark water at the left, midway up, above it.

i did a little tweaking, with contrast and sharpness mostly, to bring out the character of the clouds.

hope it comes through ok...

~"When an inner situation is not made conscious, it appears outside as fate." Karl Jung~

by melo (melometa4(at)gmail.com) on Fri Mar 21st, 2008 at 08:25:09 AM EST
[ Parent ]
I think your version is an improvement over Colman's. It retains the drama of the original. I often go for rich blacks myself in these kind of pictures.

I wouldn't have sharpened though - or at least not on the stones on the beach.

You can't be me, I'm taken

by Sven Triloqvist on Fri Mar 21st, 2008 at 10:52:10 AM EST
[ Parent ]
However it also depends on hpw your monitor is set up! I think if we could compare, we'd find quite big differences because most people use monitor settings out of the box. Unwise for pro work.

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 10:54:25 AM EST
[ Parent ]
the photo is great, i love it more, the more i see it. why don't you do a version so i can see what you mean?

the only thing that was stopping it come through for me was a washy diffused greyness, which had a banalising effect, imo.

~"When an inner situation is not made conscious, it appears outside as fate." Karl Jung~

by melo (melometa4(at)gmail.com) on Fri Mar 21st, 2008 at 12:12:36 PM EST
[ Parent ]
I tend to prefer more realistic renderings of natural scenes. I find that sort of drama over-done.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 12:20:29 PM EST
[ Parent ]
I'll try the grinch filter ;-)

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 12:30:52 PM EST
[ Parent ]
It goes with the I-hate-over-saturated-slide-film filter.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 12:31:54 PM EST
[ Parent ]
Great photo

I just adjusted the levels in Photoshop and hit the autocolor button.  And out came this.  Levels was the biggie.




"Remember the I35W bridge--who needs terrorists when there are Republicans"

by techno (reply@elegant-technology.com) on Mon Mar 24th, 2008 at 03:41:43 AM EST
[ Parent ]
Thanks, it looks good!

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Mon Mar 24th, 2008 at 04:06:19 AM EST
[ Parent ]
Photobucket

Another pier one that I knew what I wanted to achieve but haven't quite managed it. Perhaps it needs the colourful stand to be manipulated separately to stand out more.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 04:51:04 AM EST
[ Parent ]
Original histogram:

You can see it's only filling the left 3/4 of the range, with no really bright points in the image, which is fine if you wanted the image to be low-key, but I don't think you do.

Adjusted histogram - full range.

And the adjusted image:

I haven't done any colour correct to that at all.

by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:04:17 AM EST
[ Parent ]
I'm thinking I should invest in a separate monitor because I find it really hard to judge the brightness and colour on my laptop screen.  I can see the difference that makes there using the histograms.  More practice is needed.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:07:56 AM EST
[ Parent ]
For better or worse I'm in the habit of looking at the histogram on my camera after almost every shot and changing the exposure comp as desired. It's a fast process on my D40X. I'll likely keep that habit until I'm good at eyeballing the preview photo.

you are the media you consume.

by MillMan (millguy at gmail) on Fri Mar 21st, 2008 at 06:31:39 PM EST
[ Parent ]
It may be a case of two subjects in one.

This

and this

I'd have been tempted to take the photo stand from low so as to get sky in the faceholes.

by afew (afew(a in a circle)eurotrib_dot_com) on Fri Mar 21st, 2008 at 05:17:05 AM EST
[ Parent ]
Sorry to talk about framing when you're talking about techie stuff I don't understand... :-)
by afew (afew(a in a circle)eurotrib_dot_com) on Fri Mar 21st, 2008 at 05:20:41 AM EST
[ Parent ]
That's three different pictures, all telling a different story. The first one shows much more of the context, your two don't have that. On the other hand, the wider shot doesn't necessarily show either element to full advantage.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:27:22 AM EST
[ Parent ]
I had a specific shot in mind and didn't think about doing two separate ones.  I did do this shot where the lifeboat house was in one of the faces.

Here is the lifeboat house by itself.  It was a really superb building.

Photobucket

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:28:21 AM EST
[ Parent ]
Yes, I realize what you hoped to do as a composition but it doesn't turn out too well. The part to the right is the kind of tending-to-the-abstract shot of materials you like (the boardwalk trending off to infinity) (not infinity in the photo tech sense), the part to the left colourful historical-human inetrest. They probably called for separate treatment - unless you had the right kind of humans in the right places.
by afew (afew(a in a circle)eurotrib_dot_com) on Fri Mar 21st, 2008 at 10:13:31 AM EST
[ Parent ]
What I liked about the scene was the ridiculousness of the out of season, peeling cartoony image set against the grownup-ness of the pier.  The pier is made for casual strolling, admiring the view with a space of quiet reflection and this is intruded by that pitiful comedy picture begging for people who aren't there to stick their faces through and grin about it.

It's a facade.  And that becomes much more obvious in the winter when the colours become weathered and sorry for themselves and nobody engages with it. It can't compete with the real and raw beauty of the coast.

That is why I like out of season piers. Because they have to stop pretending.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 02:51:09 PM EST
[ Parent ]
That picture needed a remote, so you could take it freom one of the holes in the picture

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Fri Mar 21st, 2008 at 07:28:33 AM EST
[ Parent ]
I could have taken the photo with the timer but I thought it would look a bit sad for me to take my own photo doing that!

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 07:41:57 AM EST
[ Parent ]
Call it something like "self portrait with seaside" and it would be art. ;-)

Any idiot can face a crisis - it's day to day living that wears you out.
by ceebs (ceebs (at) eurotrib (dot) com) on Fri Mar 21st, 2008 at 10:35:44 AM EST
[ Parent ]

This is, in theory, the first of a series of contributions in which I will try and explain my mental model of how a camera works. Actual physics, chemistry or electronics is not going to be available here: while I’m reasonably good with the technical side of photography I’m not all that interested in the intricacies - I just want to be able to extract the effects I want from the tools I have. Other people can correct my idea of how the optics work, how exactly the silver grains in negatives get that way and so on. Not my problem. If I’m not clear, ask away.

A camera is, at it’s core, a simple thing: it’s a box that allows light to fall onto a piece of film or a digital sensor in a controlled way.

At the back of the box is the piece of film or the sensor (5), the details of which will obviously affect the eventual image produced - if you put black and white film in there you’re not going to get a colour picture out. At the front of the box is a hole (1) that allows light in. The distance from the film/sensor - the focal length (4) controls the angle-of-view of the image and the size of the hole controls how much light falls on the sensor. In the hole is a lens (2), which controls how the light is focused on the sensor, and a shutter (3), which controls how long light is allowed to fall on the sensor for. This gives us five basic controls: the nature of the sensor, the size of the hole, the distance of the hole from the sensor, the lens focusing and the shutter speed. Depending on your camera, some of these will be fixed, some will be chosen automatically and some can be controlled by you.

Film or sensor I don’t actually want to talk too much about the thing that we’re letting the light fall on: the film or sensor. For the moment we’ll just say that every sensor has an ISO rating, and the higher the rating, the more sensitive the sensor is and the less light it needs to form an image. Film with a rating of ISO 200 needs half as much light to form a good image as does film rated at ISO 400. There is a trade-off though: the quality of the image tends to suffer as the ISO speed increases. High ISO film tends to have much larger “grain”, while digital sensors tend to get “noisy” as the speed increases:

Low ISO = Slow = lots of light to make a picture = smooth

High ISO = Fast = little light to make a picture = noisy/grainy

Aperture - the size of the hole The hole that lets light in is covered by a magic device that allows us to set the size of the hole, it’s aperture. This is measured in f numbers, running from maybe f1.0 or so up to f64 or even higher. Ranges from f2.8 to f22 are not unusual to see on a lens. The larger the f number, the smaller the aperture - they’re fractions of the diameter of a notional circle, so that f2.8 is 1/2 the circle allowing light in, f4 is 1/4, f5.6 is 1/8 and so on.

Small f number = 1/small number = big hole = lots of light allowed in

Big f number = 1/big number = small hole = little light allowed in Aperture also affects the depth of field of the image - more on that later.

Focal length - the distance of the hole from the sensor The distance of the hole from the sensor, which is the focal length of a lens, controls the field-of-view of the image formed on the sensor by the light.

If the focal length is long, the angle of view will be small and the image will appear bigger on the sensor. If the focal length is short the field-of-view is large and the image appears small in the sensor. The details of this depends on the size of the sensor, so it’s normal to convert to a 35mm equivalent so that we can compare focal lengths on cameras with different size sensors. It would make more sense to talk about the field-of-view, but we don’t generally. Changing the focal length, either with a zoom lens - which allows you to effectively change the distance of the hole from the sensor - or by changing lens, does not have the same effect as moving closer or further from the subject. There are subtle differences in how the subject will be presented between the two.

The lens The lens, which we’re just going to consider magical for the moment, allows us to choose how far away light has to be coming from for it to be in sharp focus on the sensor. Focus 1m away and light coming from 1m will be in sharp focus. Focus at infinity and light coming far away will be in sharp focus. If we didn’t have a lens we wouldn’t get sharp pictures at all - all light would be more or less equally focused, depending on the size of the aperture. With a lens, the aperture affects how much of the picture is in sharp focus - the depth of field. Roughly, the larger the f-number and the shorter the lens the greater the range of distances around the focus distance that will be in sharp focus.

In the “drawing” above the camera is focused on the stick figure. With a small depth-of-field - typical of a long lens (85mm+) and/or a small f-number (say f1.8) only the figure would be in sharp focus, the rest of the picture would be blurred. With a large depth-of-field - typical of wide angle lens and/or large f-number (say f16) almost the entire picture would be in focus, with little blurring showing anywhere.

Controlling how long the light falls for - the shutter The length of time the shutter is open is the other part of what controls how much light falls on the sensor. It also controls how much freezing or blurring of movement can appear on the image. High shutter speeds allow in little light and freeze movement, while slow shutter speeds allow in lots of light but movement will blur. 1/500 of a second is fast. 1/30 of a second is slow.

Putting it together The ISO of the sensor controls how much light it needs to make a good image. The aperture and the shutter speed control how much light falls on the sensor. The focal length controls the field-of-view that the light will come from Taking a picture is a matter of balancing those controls.

  • Do you need a specific shutter speed? If you’re taking pictures of fast action you’ll want a fast shutter speed, and you need a speed of at least about 1/50 of a second even to take a portrait.
  • Do you need a specific aperture? If you want a lot of the picture to be in focus then you’ll want a big f-stop. If you want the background to blur you’l need a small f-stop.
  • Can you get enough light onto the sensor? In low light you may need a big aperture and a slow shutter speed.
I’d appreciate if people could add pictures with examples of the choices of parameters below, and explain what choices they made.

by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:13:58 AM EST
[ Parent ]
Great stuff. That has just helped me to understand something that I didn't get before.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:22:39 AM EST
[ Parent ]
Which thing?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:27:58 AM EST
[ Parent ]
Putting context to focal length.  I'd not grasped what the mm numbers on lenses really meant.  How embarrassing!

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:33:50 AM EST
[ Parent ]
In this shot, I wanted the surface of the stone to be in focus but the sand to be blurred out.  It was a macro lens so the effect of short depth of field is usually something that ruins these photos because the DOF is way too narrow and I find out afterwards that the bit i thought was in focus actually wasn't.

Photobucket

In the shot I posted in photos as usual of the spiral shell on the sand I wanted shell and sand to be in full focus because the detail of the grains worked really well with the shell.

In this one I wanted the eye to be drawn to the holes in the stone - although I wonder if the DOF could have been a bit larger because the blurred side of the stone on the right hand side is a bit distracting.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:42:58 AM EST
[ Parent ]
Film with a rating of ISO 200 needs half as much light to form a good image as does film rated at ISO 400.

Is there a mistake in this sentence, or does "higher ISO" means lower number, or am I not awake yet to comment on technical matters?

Great tutorial, BTW. Helps clarify my misformed notions that came from a physics rather than photography viewpoint.

Un roi sans divertissement est un homme plein de misères

by linca (antonin POINT lucas AROBASE gmail.com) on Fri Mar 21st, 2008 at 06:24:40 AM EST
[ Parent ]
Higher ISO is a higher number.

For a film camera, a bright day would use ISO 100.  An overcast day would use ISO 400 which needs less light to capture a photo with.  

With digital you can get very large ISO numbers for night shots and very low light but it does get very grainy eg at ISO 1600.

Ad astra per aspera

by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 06:28:30 AM EST
[ Parent ]
And I think Colman meant to put ISO 200 needs twice as much light as ISO 400.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 06:29:56 AM EST
[ Parent ]
Yes, of course I did. Thanks. Can't edit the comment of course.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 08:26:42 AM EST
[ Parent ]
You were checking that we were paying attention weren't you?!

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 08:42:20 AM EST
[ Parent ]
Yes. Yes I was.
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 08:44:56 AM EST
[ Parent ]
All the best teachers do it.
by afew (afew(a in a circle)eurotrib_dot_com) on Fri Mar 21st, 2008 at 10:20:04 AM EST
[ Parent ]
That was great, Colman.

Is it worth adding that, in old money, the ISO was sometimes referred to as the "speed" of a film?

In other words, for a given light level, you can take a picture with a higher shutter speed/shorter exposure if you're loaded with a "fast" (ISO 400) film than a "slow" one (ISO 100).

Where you really notice this is in photographing moving objects that you want to keep in focus.  Like children.

by Sassafras on Sat Mar 22nd, 2008 at 08:24:13 AM EST
[ Parent ]
Yup: I have a pile of rolls of Ilford XP5, which is ISO 400, ready to load into the Nikon EM, together with the 50mm 1.8 for photography when baby arrives - if I rate it at 800 or 1600 (B&W film speed is more-or-less a suggestion, you can alter the effective speed by changing the develoment time)  I should be able to get smooth enough pictures in available light in the hospital. I don't want to be using much flash on a newborn. I'd like to create some artifacts recording the event, not just collections of photons on a member card.
by Colman (colman at eurotrib.com) on Sat Mar 22nd, 2008 at 09:49:00 AM EST
[ Parent ]
I was also trying to avoid too much jargon at once. You'll notice I didn't mention large vs. small apertures as opposed to large vs. small f-numbers.
by Colman (colman at eurotrib.com) on Sat Mar 22nd, 2008 at 09:49:59 AM EST
[ Parent ]
What is the blue dot in these photos. It's not some heavenly body which the eye doesn't see?



Hey, Grandma Moses started late!

by LEP (rafifoon@yahoo.com) on Fri Mar 21st, 2008 at 05:34:36 AM EST
[ Parent ]
Is it flare from the moon? Or something on the sensor?
by Colman (colman at eurotrib.com) on Fri Mar 21st, 2008 at 05:38:16 AM EST
[ Parent ]
I got similar flare in some shots when I was taking photos of the eclipse last year.  I reduced it by reducing the shutter speed a bit, which also brought out a little more detail of the surface of the moon.

Ad astra per aspera
by In Wales (inwales aaat eurotrib.com) on Fri Mar 21st, 2008 at 05:44:19 AM EST
[ Parent ]
I think it's something technical- I have no idea what. It's on almost all the photos I took of the moon but not always in the same place. I hope it's not G'd fucking with me.

Hey, Grandma Moses started late!
by LEP (rafifoon@yahoo.com) on Fri Mar 21st, 2008 at 05:44:28 AM EST
[ Parent ]
It's a reflection inside the lens of the bright spot of the moon. It will move about in relation to the framing of the bright spot to the geometry of the lens interior

You can't be me, I'm taken
by Sven Triloqvist on Fri Mar 21st, 2008 at 06:43:05 AM EST
[ Parent ]

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