News:

And we're back!

Main Menu

Digital Photography for Dummies

Started by alfred russel, April 17, 2011, 06:06:14 PM

Previous topic - Next topic

Jacob

AR - the basic technical elements of photography are Exposure Time and Available Light.  As the Available Light decreases, the Exposure Time increases (to get enough light to the sensor/film to capture the image). At some point or other, the Exposure Time will increase to the point that the camera picks up your hand shaking, causing blurry images (I'm assuming you're shooting on an automatic setting here, because if you're shooting on manual settings you should know enough about these basics to know why you're getting blurry pictures to begin with).

The fix to that, as has been suggested upthread, is to use a time-delay exposure. Put your camera on a tripod (simply placing it on a flat surface works fine too, assuming you can still frame the shot the way you want). This allows longer Exposure Times without picking up any shaking.

Alternately, you're getting blurry pictures because you're trying to capture fast moving objects when your exposure time is too slow, resulting in motion blur. The only fix to this is decreasing your exposure time, which basically means getting more light into the scene. Realistically, the only fix to this is getting a camera with a better lense and sensor.

12 megapixels are more than enough for printing 8 by 10 and larger than that too, no problem. The limiting factor is the lighting and the quality of the camera hardware.

You can get perfectly good shots out of most compact cameras, like the one you have, but you're likely going to get the best ones if you limit yourself to shooting during daylight (unless you like artsy blurry shots), things that aren't moving too fast and/or use a tripod or otherwise keep the camera more stable than when held in your hand.

If you're thinking of getting a tripod, get one of those cheap little $10 ones.

With a compact digital camera like yours, pretty much the only time using the flash is worthwhile (assuming you're going for frameable "nice photography" type shots) is when you're filling in backlit scenes/ when the primary subject is in a darker part of the picture. I.e. if you're shooting someone standing under a parasol on a bright day, the camera will often calibrate the exposure to match the sunlit background. This results in the subjects face looking very dark; that is, unless you use the flash.

Jacob

Quote from: Oexmelin on April 18, 2011, 03:16:53 PM
I am going to take advantage of Russel's thread to ask for recommendations myself. My camera is getting oldish (4 megapixels)... plus, I would like to buy a better one if only for the fun of taking pictures.

I need a good camera to take tons of pictures of old papers. Most public archives (damn you, private research libraries!) permit visitors to take their own pictures... I need readability - not necessarily perfection. What do I need to look for?

Also, what's the difference between "point-and-shoot" and other so-called "types" out there (i.e., "compact", "DSLR": I know what these stand for, but point and shoot?)

Yeah, what Pedrito said: point-and-shoot and compact are pretty much the same thing.

If you're taking tons of pictures of old papers, honestly you're probably fine with your old camera (or any other new compact one). The real difference is going to be in your set-up.

Were I in your situation, I'd bet one of those cheap little $10-$20 mini-tripods and use it to set up a temporary "photography station" when I was shooting lots of documents. Set up the camera to point at a specific area where you'll put the documents you're photographing, one-by-one. Make sure the area is well and evenly lit and the camera is set to not use a flash (you're relying on the tripod and external lighting). Ideally you'd have a remote control to take the photograph, but that's probably only on cameras that are too expensive for your general purposes; setting your normal camera on 2-second time delay (or whatever the shortest time is) should do the trick.

That's basically how archival and serious documentation photography is done, only with better equipment and more permanent set-ups.

But the basic principle of getting your set-up right the first time and then powering through everything you have to document in the session will probably improve your results and workflow more than buying a big fancy camera that you don't know how to use (unless of course you want to learn how to use it, but that doesn't make setting up properly not useful).

But if you're just aiming for readability, most average point-and-click cameras should be just fine. Of course, if you're looking for an excuse to buy a fancier camera, just increase the quality requirements for your documentation :)

Jacob

Two other digital photography things:

1. dpreview.com is a great review site for cameras. It might be a little technical and go into too much detail if you're not into cameras, but you might end up becoming a camera nerd if you go there a lot - or you can just skip to the conclusion part of the reviews. The site has a very nice side-by-side comparison feature.

2. When buying a digital camera, the first rule of thumb (if you're not going to review in depth): the bigger the lens, the better the pictures.

alfred russel

Quote from: Jacob on April 19, 2011, 12:48:30 AM
AR - the basic technical elements of photography are Exposure Time and Available Light.  As the Available Light decreases, the Exposure Time increases (to get enough light to the sensor/film to capture the image). At some point or other, the Exposure Time will increase to the point that the camera picks up your hand shaking, causing blurry images (I'm assuming you're shooting on an automatic setting here, because if you're shooting on manual settings you should know enough about these basics to know why you're getting blurry pictures to begin with).

The fix to that, as has been suggested upthread, is to use a time-delay exposure. Put your camera on a tripod (simply placing it on a flat surface works fine too, assuming you can still frame the shot the way you want). This allows longer Exposure Times without picking up any shaking.

Alternately, you're getting blurry pictures because you're trying to capture fast moving objects when your exposure time is too slow, resulting in motion blur. The only fix to this is decreasing your exposure time, which basically means getting more light into the scene. Realistically, the only fix to this is getting a camera with a better lense and sensor.

12 megapixels are more than enough for printing 8 by 10 and larger than that too, no problem. The limiting factor is the lighting and the quality of the camera hardware.

You can get perfectly good shots out of most compact cameras, like the one you have, but you're likely going to get the best ones if you limit yourself to shooting during daylight (unless you like artsy blurry shots), things that aren't moving too fast and/or use a tripod or otherwise keep the camera more stable than when held in your hand.

If you're thinking of getting a tripod, get one of those cheap little $10 ones.

With a compact digital camera like yours, pretty much the only time using the flash is worthwhile (assuming you're going for frameable "nice photography" type shots) is when you're filling in backlit scenes/ when the primary subject is in a darker part of the picture. I.e. if you're shooting someone standing under a parasol on a bright day, the camera will often calibrate the exposure to match the sunlit background. This results in the subjects face looking very dark; that is, unless you use the flash.

Thanks Jacob. I'm basically shooting pictures of buildings in daylight. Is it worth it to try to manually reduce the exposure time to a very low level? Or should I just get a tripod and stay with the manuel settings?
They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety.

There's a fine line between salvation and drinking poison in the jungle.

I'm embarrassed. I've been making the mistake of associating with you. It won't happen again. :)
-garbon, February 23, 2014

Warspite

Were I in your situation, I'd bet one of those cheap little $10-$20 mini-tripods and use it to set up a temporary "photography station" when I was shooting lots of documents. Set up the camera to point at a specific area where you'll put the documents you're photographing, one-by-one. Make sure the area is well and evenly lit and the camera is set to not use a flash (you're relying on the tripod and external lighting). Ideally you'd have a remote control to take the photograph, but that's probably only on cameras that are too expensive for your general purposes; setting your normal camera on 2-second time delay (or whatever the shortest time is) should do the trick.

That's basically how archival and serious documentation photography is done, only with better equipment and more permanent set-ups.[/quote]

With a tripod, he'll need to take care of depth-of-field considerations, otherwise the ends of the documents will be blurred.
" SIR – I must commend you on some of your recent obituaries. I was delighted to read of the deaths of Foday Sankoh (August 9th), and Uday and Qusay Hussein (July 26th). Do you take requests? "

OVO JE SRBIJA
BUDALO, OVO JE POSTA

Oexmelin

Quote from: Warspite on April 19, 2011, 09:10:27 AM
With a tripod, he'll need to take care of depth-of-field considerations, otherwise the ends of the documents will be blurred.

Thank you!! This is exactly what's happening - and I was wondering what was involved.

Typically, I don't use the tripod unless I am shooting an entire register: the hassle - and time! - of installing the tripod, modifying the set up for the various formats of documents prevents me from using it systematically. It would simply take forever. The downside is that I get, once in a while, a document which is too blurry to be read. Frustrating, but it enables me to get a lot more done, in what are shorter and shorter research trips.
Que le grand cric me croque !

Warspite

If you get the right kind of tripod, you can adjust the camera to look straight down. This gives you a much shallower required depth of field. If your camera lets you, try to set it to smallest aperture possible (a smaller aperture, the hole through which light enters, gives a deeper depth-of-field).

You could always try a jerry-rigged apparatus; use two stacks of books, with cardboard running between them like a bridge. Cut a hole in the board through which the camera lens could poke, and photographe documents that way (making sure not to use flash!!).
" SIR – I must commend you on some of your recent obituaries. I was delighted to read of the deaths of Foday Sankoh (August 9th), and Uday and Qusay Hussein (July 26th). Do you take requests? "

OVO JE SRBIJA
BUDALO, OVO JE POSTA

Jacob

Quote from: alfred russel on April 19, 2011, 07:39:52 AMThanks Jacob. I'm basically shooting pictures of buildings in daylight. Is it worth it to try to manually reduce the exposure time to a very low level? Or should I just get a tripod and stay with the manuel settings?

As long as your exposure time is 1/60 or less, you shouldn't be getting blurriness from handshaking. You can probably push it to 1/30 if you brace your arm appropriately. Manually reducing the exposure time below that shouldn't make a difference, but since it's digital there's no harm in playing around with it. I'd also play around with the time release thing, while having the camera sitting on a flat surface. If that gives you better results, then you might consider getting a cheap tripod. Since you're shooting buildings, you might as well take advantage of the benefits of a tripod; you could deliberately set a very slow exposure - the building should then be nice and sharp, but people moving about will end up blurred which could give you an interesting effect.

Another thing that might be causing you to get blurry pictures is if the camera auto-focuses on something in the foreground, causing the building to be outside the depth of field. If that's the case, you'll probably want to switch the setting to "landscape" instead of "portrait" or something similar (or compose your picture without the thing in the foreground).

... but really, one of the main tricks to being a good photographer is taking many many pictures of the same thing and picking (and only showing) a small selection of the best shots. This is so much cheaper with digital than with film, so you might as well play around a bit. Have fun, and post some of your shots :)

Jacob

QuoteWith a tripod, he'll need to take care of depth-of-field considerations, otherwise the ends of the documents will be blurred.

Well, I sort of assumed he'd set it up to do so anyhow. Is there something about using a tripod that makes the depth-of-field considerations worse than if he held the camera by hand?

I've only really done this sort of thing for documenting artwork rather than shooting thousands of document pages, so maybe I'm missing something obvious.

Jacob

Quote from: Oexmelin on April 19, 2011, 10:57:20 AMThank you!! This is exactly what's happening - and I was wondering what was involved.

Interesting. I just a couple of test-shots with my own point and click and I got pretty decent results; no depth of field issues there. How close are you holding the camera from the document? How big are the documents and what's the lighting like?

QuoteTypically, I don't use the tripod unless I am shooting an entire register: the hassle - and time! - of installing the tripod, modifying the set up for the various formats of documents prevents me from using it systematically. It would simply take forever. The downside is that I get, once in a while, a document which is too blurry to be read. Frustrating, but it enables me to get a lot more done, in what are shorter and shorter research trips.

You know your workflow better, obviously :)

Warspite

Quote from: Jacob on April 19, 2011, 12:50:08 PM
QuoteWith a tripod, he'll need to take care of depth-of-field considerations, otherwise the ends of the documents will be blurred.

Well, I sort of assumed he'd set it up to do so anyhow. Is there something about using a tripod that makes the depth-of-field considerations worse than if he held the camera by hand?

I've only really done this sort of thing for documenting artwork rather than shooting thousands of document pages, so maybe I'm missing something obvious.

I'd wager your artwork is hanging on a wall, rather than laying on a desk; the former allows a more natural pose to take the photo, as opposed to an extended arm over a table. Often people try to photograph a document on a table by snapping away from one end to the other. At the close ranges needed for a readable product, depth of field has a big effect, rendering one end blurred (or even both sometimes). It's good practice to always ensure the focal plane is parallel to that of the document you are photographing.
" SIR – I must commend you on some of your recent obituaries. I was delighted to read of the deaths of Foday Sankoh (August 9th), and Uday and Qusay Hussein (July 26th). Do you take requests? "

OVO JE SRBIJA
BUDALO, OVO JE POSTA

Jacob

Quote from: Warspite on April 19, 2011, 01:18:27 PMI'd wager your artwork is hanging on a wall, rather than laying on a desk; the former allows a more natural pose to take the photo, as opposed to an extended arm over a table.

Oh absolutely... which is why my instinct would be to do a setup with a tripod, since the more akward the photographing pose is, the more useful a tripod or similar setup is. Personally, I'd probably put the camera on one of those little $10-$20 tripods and jam it in between a stack of books or otherwise secure it so it faces down.

QuoteOften people try to photograph a document on a table by snapping away from one end to the other.

When you say "from one end to the other" do you mean laying out all the papers on a big table and moving from page to page? Or flipping through the document with one hand while seated, snapping away with the camera in the other hand?

QuoteAt the close ranges needed for a readable product, depth of field has a big effect, rendering one end blurred (or even both sometimes). It's good practice to always ensure the focal plane is parallel to that of the document you are photographing.

Yes, the focal plane should be parallel to the document you're photographing. If it's not, that's probably the most basic thing to correct first, along with keeping the document as flat as possible :)

In any case, it sounds like the main difficulty is less one of the quality of the camera and photography theory, and more about figuring out the most practical, comfortable and efficient workflow.

Warspite

Quote from: Jacob on April 19, 2011, 01:30:48 PM
In any case, it sounds like the main difficulty is less one of the quality of the camera and photography theory, and more about figuring out the most practical, comfortable and efficient workflow hiring an unpaid intern.

:yes:
" SIR – I must commend you on some of your recent obituaries. I was delighted to read of the deaths of Foday Sankoh (August 9th), and Uday and Qusay Hussein (July 26th). Do you take requests? "

OVO JE SRBIJA
BUDALO, OVO JE POSTA

Oexmelin

Quote from: Warspite on April 19, 2011, 11:35:54 AMYou could always try a jerry-rigged apparatus; use two stacks of books, with cardboard running between them like a bridge. Cut a hole in the board through which the camera lens could poke, and photographe documents that way (making sure not to use flash!!).

Contrary to what that Angels & Demons movie would lead you to believe, no public archives in the world lets us smuggle in stacks of books, or organize our workspace that way  ;)
Que le grand cric me croque !

Oexmelin

Quote from: Jacob on April 19, 2011, 01:00:57 PMInteresting. I just a couple of test-shots with my own point and click and I got pretty decent results; no depth of field issues there. How close are you holding the camera from the document? How big are the documents and what's the lighting like?

All of these answers vary considerably. Typically, notarial archives vary in size from the equivalent of one half to a complete A4 page. Official correspondance of the 18th c. can go to double that size. Bound documents are equivalent to book sizes (in-4o, in-8o, in-16 being the most common). I usually try to get one A4 to fit my screen if the writing is neat, one half if it isn't.

Most archives were constructed way before digital photography (sometimes, way before photography proper: in Avignon, it used to be in the Papal Palace). They usually included a professional studio for the archives' own photographer, or the rare historian who could take decent pictures, in controlled conditions, for a limited series of prints. Now, we all take pictures in the main reading rooms, Which means that there are usually considerable variations in lighting according to the presence, size, or absence of windows; weather, the place you are assigned, etc. Archives are also widely unequal in how they treat historian-photographers. National Archives of the UK gives us access to tons of props to get documents to stay flat (weights, frames, etc.). Archives Nationales in Paris gives us nothing. All others fall between those two extremes.
Que le grand cric me croque !