Histograms

Histograms

Now from these Two Videos you should have a pretty good understanding on how your cam records a image and why the Histogram is so important. But if you still don't get it let me dump my two cents in to your learning bucket

A properly exposed picture will have a somewhat even spread of pixels through out the histograms X axis, form Zero the darkest pixel your camera can record to 255 on the right side the brightest pixel your camera can record. for a total brightness scale 0f 256 (0 to 255).

If you under expose a picture you will have most of your pixels to the far left side with most of your image falling out side of your cameras range (PIXELS THAT ARE BEYOND 0) this means your camera did not even see that part of the picture, the image was so under exposed that the darkest shadows of your pic has no detail at all it's just black

and If you over expose your picture the same thing goes for the right side of the histogram if you over expose to much the high lights in your image (THE BRIGHT AREAS ) will show up as pure white with no detail to them at all, We call this blown high lights or a washed out pic.

The key is to try and use your camera full range from the darkest dark to the whitest white, this will give you a pretty even exposer, giving you detail in your shadows as well as your high lights.

But sometimes you can't reach the whole scale with out changing the mood of the pic, you don't wanna shoot a night scene where you can't even tell it's night time.

When you are capturing a image and most of the image is dark or in shadow most of your image pixels will be to the left of your histogram. This is fine as long as you don't touch or go past the 0 pixel mark, for every pixel you go over 0 that means that pixel is lost and will not be represented in your image. once again same thing for real bright pictures go as far to the right as you can with out passing 255.

Well How do I move my pixels when i take a pic?

Simply change your aperture or shutter speed. your image was under exposed because you didn't let enough light hit your film/sensor. And since you have read my other post you know you can let in more light three ways, shoot at a longer shutter speed, open up your lens aperture , increase your cameras sensor sensitivity to light by raising your ISO.

I'm back

I know I know, I have been gone for awhile. I had alot going on but I'm back now thanks to a new friend, a fellow photographer re inspired me to pick this project back up. So lets go. I think we left off on ISO, we are now moving on to The Histogram. The Histogram is one of the most powerfullest (lol, IS THAT A WORD?) and most unused misunderstood features on our cameras.

I guarantee you after you learn how to read a Histogram you will never take another over/under exposed picture again you ready? watch this lil Video then join me as we dive into the Histogram

Shutter Speeds, To Freeze or Not To Freeze? That is The Question.

Learning Level 1

Shutter speeds, I think this is alot easier to explain and grasped than Apertures and ISO. Is simply a matter of time . Most cameras on the market today gives you the option to change your shutter speeds. This is a typical shutter range on a DSLR.

<--Slow /Blur Fast/Freeze-->

---

1 sec. 1/4 1/8 1/15 1/30 1/45 1/60 1/90 1/125 1/180 1/250 1/350 1/500 1/750 1/1000 1/1500 1/2000

---

This is just a sample scale, my cameras shutter speed goes down to 30 seconds, it also has a Bulb setting that allows you to hold open the shutter for as long as you want by keeping the shutter release button pressed.

---

---

Ok, lets move on. Being able to adjust your shutter is valuable in two ways, it allows you to shoot in low light with out the aid of a flash, and it also allows you to apply artistic effects to your photos.

IT can even tell Lies....

Yes a mechanical non living device has the ability to lie.

The shutter allows you to show motion in two ways, by freezing it or letting it blur.

Lets say you or at a NASCAR event and you wan't to show your friends back at home your adventures if you snap your shots at 1/500 and greater you will have a nice sharp boring picture. I say boring because shooting a car at a shutter speed that fast will completely freeze the car making it look stationary lol you are at NASCAR shooting some of the fastest cars on the planet and your photos makes the cars look like they are parked or broke down on side the road.

Wouldn't a shutter speed of 1/125 that allows a lil motion blur to show be a more appealing picture?

Ok , so shooting to fast is bad right?

nope, that's not what I'm saying, you as the artist and the writer of light has to know how you wanna tell your story. let's say you or shooting flowers after a nice rain and you pull out your new fancy Marco lens and see a shot you wanna capture. there is this one flower that is getting a rhythmic drop of water on it's petal and you know this is a money shot you chose a small aperture because you wanna isolate the single flower from the rest of the cluttered background. For this shot I would chose the fastest shutter speed I could use while still retaining a correct exposure. I want a fast shutter speed cause i want to catch the explosion right as the rain drop makes contact with the flowers petal. I want to freeze the smaller water fragments in mid air as they explode from the main droplet. one good use for a slow shutter speed on water is what we call a angel hair effect.

Phot by: doniedsilva
See how the water looks soft and milky, this is accomplished by a slow shutter speed allowing the waters natural movement to be relayed to your photo by a slow shutter speed.

---

Another great use for slow shutter speeds is night photography. I shot this image at 2:00 am in thick fog. Both of these were shot at slow shutter speeds of a minute are longer do to the fog and I was using a aperture of F22 for maximum depth of field and ISO 400 to cut down on noise.




Noise, lol this dude is off his rocker what is he talking about noise for? This isn't a TV broadcast or radio, why is he talking about noise?

LOL, yes indeed, a photo can be real noisy, especially in a dimly lit stadium full of screaming fans. But don't worry, When you are forced to take photos in a potentially noisy place I will introduce you to the photographers secret Assassin The Noise Ninja....

Follow me to ISO/Film Speed


Wait a minute, you told us the shutter can tell a lie, did you lie?

Well I did explain how the shutter can tell it's own verion of the truth but if you want one more example here it goes.


There were these two neighbors who always got in to it over a new motorbike that was bought Tom use to always complaint to Jim about the noise that Jim made early in the morning when he was heading to work. After a few weeks of fussing back and forward over the fence and trips and calls to the police Tom decided to set Jim up. One Sunday evening Tom set up his tripod and cam in his living room opened up the window and waited for Jim to pull up. as Jim turned the corner and headed down the street to his house Tom fired off a few shots.

The next day the police were at Jim's house responding to a report of speeding in a residential area. Of course Jim denied everything knowing that his street is populated with many kids who like to play kick ball in the street on the weekends and he never would speed. But after the police produced a photo of him zooming by a clearly posted 15 M.P.H. speed sign his jaw dropped, The photo showed Jim going so fast that you could see streaks of color trailing behind him.

Now to a untrained eye this would be a very believable photo. But little did they know that Tom had set his shutter speed so slow that even if a kid would have rode by on a tricycle the pic would give the illusion of the lil kid doing well over 50 M.P.H.

ok, now can we head to ISO?