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posted : 2004.Dec.14 @ 11.48am
Good day everybody!
I am relatively new to photography, I never even took photos until a couple years ago when I got my first camera, an Olympus C4000Z. As time goes by I am getting increasingly obsessed with this art form, thus I have myriad questions, questions that are not necessarily easy to get answers to by surfing the internet. I need people I trust to talk to about this stuff, and I'm guessing there are others here in the same boat.
So I thought I would start a thread for discussion about different photographic techniques, technical jargon, hardware.... etc.
I thought it might also be cool to say what kind of camera we are using and talk about what we like/dislike about it.

One of the first things I want to learn about is what exactly is the difference between a dSLR and a normal digital camera? What are the advantages and disadvantages? Is it true that with an SLR you can't take shots using the LCD screen?

Thanks so much everyone, I hope I'm not being too nosey.....
Very Happy







posted : 2004.Dec.14 @ 1.10pm
hey there.. i think that's a good idea.. a thread for just talking about techniques, general info, faq's.. stuff like that.

It's a loaded question you ask.. one that could take pages and pages of descriptions, details, and info.. but I'll try to do my part and answer it short and sweet. Maybe someone else can elaborate on it.

I won't just limit it to digital... If a 35mm SLR is to a dSLR.. then a 35mm point and shoot camera is to a basic digital camera. Lots of features and qualities and differences in there.. I know.. just a generalization.

SLR - Single Lens Reflex
SLR's provide an enormous amount of control, (focus, exposure, aperature.. etc)
You can change lenses.
They use through the lens viewfinders. What you see in the view finder is what the lens is seeing.

Point and shoot are just that.. point and shoot.
No control over exposure, focus.. etc. It's basically auto.

For the digital world.. it's basically the same.
Alot of non dSLR's have some good manual features on them.. where you can adjust focus, exposure.. etc. The more you pay.. the more features you get.. really.
There are prosumer digital cameras.. that are very close to a dSLR.. the big difference is.. you can change lenses on a dSLR. And yes.. on a dSLR.. you can't view the lcd for taking the picture. It's for review/playback only. So far.
The other big difference on a dSLR compared to a digital camera or prosumer digital camera.. is the sensor. The sensor size on a dSLR is about 4x bigger than the best sensor on a normal digital camera. This means much more info getting captured.. (light, detail, etc)

That was probably so vague it didn't even help.. but I hope it did.. even a little bit.
Like I said.. there's tons and tons of info out there that could be wrote about this question.. that's a tasty sampling.
Maybe someone has some good links to FAQ's , comparisons.. etc.
Here's a Word Document I found that has some good basic info.
Talks about film and digital.
http://www.umsl.edu/technology/frc/worddocs/point_shoot.doc Cool







posted : 2004.Dec.15 @ 12.07pm
No, this is very helpful, thanks a lot.
I think sometime in the next year I might get a more powerful camera and one of the things it seems like it's hard to get a consumer or even a prosumer camera to do is take really long exposures. My camera has a "Night Mode" and an adjustable ISO (i don't truly understand what an ISO is) if I turn off the flash and set the ISO at 100, in night mode it will give me a long exposure, but the camera decides how much to give me based on how much light is available. I'm not exactly sure how to get the results I want but I don't have a lot of room to experiement.
I absolutely love the macro capability on my camera though. I wonder how much money would have to be spent on a lense to do macro after the purchase of an SLR.
I'm assuming it would require a special lense right?







posted : 2004.Dec.17 @ 1.35am
here's quick break down of the basics, sorry if I'm going over stuff you know.

iso: simply put it is the sensitivity to light, the higher the iso number the less light needs to fall on the sensor to get a correct exposure. However as with film, the higher the iso rating the more noise there will be on an image. ( ISO is from film ratings for example 100, 200, 400, 800 doubling the iso speed gives you an extra "stop" of light).

ShutterSpeed: very straight forward, it is just how long the shutter stays open. Longer shutter speeds are needed in low light conditions, but can also be useful for effects such as blurring of movement. I used a long shutter speed for this shot.


There was enough light to let me use a quicker shutter speed, but I wanted movement blur.

For my nightscapes I used what is known as the Bulb setting. Essentially as long as the shutter button is pressed, the shutter stays open. Some prosumer cameras have a bulb setting, however beware. My old FujiS7000 had "bulb" or so it claimed. However, it only lasted for up to 15seconds, so wasn't bulb at all... Mad I was tad annoyed when I discovered this, after purchase.

Aperture. This one usually throws people because of the way the numbers run, it seems confusing at first. The higher the number you set your aperture to, the smaller the hole, i.e.: f2.8 lets in lots of light, f22 lets in very little. ( f132 or smaller for pinholes ). Where the confusion comes in is that people say "I used a big aperture", this refers to the physical size not the number, i.e. they are referring to using f2.8 not f22.

You use a combination of iso, shutter speed and aperture to give you the right amount of light to expose the shot.

Macro: yes you need specialist lenses, these can range in price from £100 to £1000 or more. A cheaper alternative is to use close-up filters, which go in front of your lens. Theses give higher magnification to your shots and are good way to start.

ok that's it for now. Very Happy







posted : 2004.Dec.17 @ 8.43am
Excellent info Mark!

Here's a little 'side effect' of each of the three things mentioned to combine to get a proper exposure.
Some stuff to keep in mind.

ISO - the higher the ISO speed.. the grainier/more noise the picture will have.

Shutter Speed - the slower the shutter speed the more prone to get 'camera shake' you are.
General rule is around anything below 1/50 should be on a tripod. Some people can hold 'er more steady than others tho. Focal length can change this tho.
If you have a 28mm wide angle.. then you can maybe get 1/30 without camera shake.
But if you have a 200mm zoom.. you won't be able to go below 1/250 before camera shake.... etc.
Whatever the focal length.. stick a 1/ in front of it.. and that's your minimum shutter speed before needing a tripod.. (may have to round up a bit)

Aperature - The larger the aperature (smaller the number) gives a shallower depth of field. (amount of subject in focus) - good for portraits to blur out the background.
The smaller the aperature (larger the number) gives a greater depth of field - good for landscape..to make sure everything is in focus.

Hope that helps out Smile
I know the stuff in my head.. but have a hard time writing it out to explain.







posted : 2004.Dec.17 @ 9.02am
This is fantastic you guys! This is actually starting to make sense. It looks like my camera has a manual mode that will allow me to do from 1/1000th to a 16 second exposure and my aperature goes from f2.8-f11. I can do auto ISO, 100, 200 and 400. I've messed with it before but I didn't know what everything did.
Some more questions...

1. So for the water shot, since you have enough light, when you set the shutter to stay open a long time do you have to set the aperature to a high number to keep the image from being pure white?

2. When doing a bulb exposure, deosn't letting go of the shutter cause the camera to shake a little bit, thus creating a blur?

3. What is the advantage of using a high ISO if it gets more grainey the higher you go?

4. What causes the graininess at a high ISO?

Thank you so much for taking the time to help with this stuff. You guys are great!
Very Happy







posted : 2004.Dec.17 @ 9.21am
Glad it's helping!

1 - Yes. I stopped down to f22. I also used neutral density filters ( essentially a semi-opaque grey piece of plastic), to reduce the light entering the camera even further, allowing for a longer shutter speed.

2 - Again, yes. For this i use a cable release that allows you to minimise shake even more.

3 - High iso's allow you to use smaller apertures ( to get greater depth of field) or faster shutter speeds in low light. Faster shutter speeds will allow you to freeze action or use longer length lenses, as Foz mentioned you need (on average) a shutter speed that equates to your lenses focal length to stop camera shake.

4 - Grain is caused by sensitivity. With film, a general rule of thumb is, "the more sensitive the emulsion on a film is to light, the greater the grain" For digital cameras this noise is caused by the processing of the image. To get higher iso ratings, digital cameras boost the signal sent from the ccd and so cause more noise in an image.







posted : 2005.Jan.19 @ 1.18am
Hello. Many thanks for this info.
Using it has inspired me to take a general photography class.
I'm interested in people's suggestions on what might be a good 35mm SLR to start out with.
Anyone? So far someone recommended the Canon AE-1. Any input would be awesome Angel







posted : 2005.Jan.19 @ 1.25am
"Back in the day" I used both an Olympus OM-1N and a Nikon FN. Both had superior optics, good sturdy cameras. A manual film camera is a great teacher. You really focus on the process. Both of those cams were fully manual no bells, no whistles. I loved using them.







posted : 2005.Jan.19 @ 2.02am
ah yes, I looked up the OM-1n on pbase and the images look pretty nice. I can't find the FN anywhere, was there something else to the name?
What lenses did you use?







posted : 2005.Jan.19 @ 2.06am
Air, with the olympus how easy did you find it to use the shutter speed dial? It is the om-1 that has it located just behind the lens isn't it? Just wondering as I was thinking about getting one a while back.







posted : 2005.Jan.19 @ 2.33am
I liked it. It was fast. Repetition and muscle memory made finding F-Stops and shutter speeds without looking easy, hand position and all that. I believe it used to be the field camera for National Geo once upon a time.







posted : 2005.Jan.19 @ 2.35am
It was the quirky layout that made me consider it, as I was looking for an old manual that i could still find good quality lenses for. (My old screw thread slr is getting hard to find stuff for these days) However, i found an excellent value pentax instead.






    

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