Learn Photography Master Thread

[Achas Veachas]

(they're coming, I promise !),

I don't want to pressure you, you are after all doing us a favor, just letting you know that we're waiting here...

[askmoses]

I don't want to pressure you, you are after all doing us a favor, just letting you know that we're waiting here...

+1

[Ez]

I don't want to pressure you, you are after all doing us a favor, just letting you know that we're waiting here...

+1000

Every time i see this thread in my "Unread" list, I'm getting all excited again...

[theberk]

+1000

Every time i see this thread in my "Unread" list, I'm getting all excited again...

Me too

[whYME]

1. What did I do wrong here?
Why is the picture so grainy? (is that the right word for it?)
Is it something with the exposure? (Or could it be something as stupid as it just being out of focus?)

2. Thoughts / comments on the two crops?

[moish]

grain could be due to a high iso

[Something Fishy]

grain could be due to a high iso

Exactly. See the difference after applying some basic noise-removal settings in Lightroom (settings on the right):

[chucksterace]

Feedback anyone?!?!?

[MC]

I really like the perspective in the second one!

[moish]

its a picture of an aeroplane

[whYME]

grain could be due to a high iso

Exactly.

Thanks.

Any idea what my ISO should've been here?
Or for that matter how high I can go with a t3i without having to worry about noise? (Google has not been my friend on this so far...)

[Something Fishy]

Thanks.

Any idea what my ISO should've been here?
Or for that matter how high I can go with a t3i without having to worry about noise? (Google has not been my friend on this so far...)

You should always be on the lowest ISO possible... Your picture was taken at ISO 1600 and f/13. In reality you could have shot it at 2.8, since evening in your shot is at infinity so it would all still be in focus. Had you done that, you could have dropped your ISO by a corresponding 4.5 stops to below 100.

You could have also used a longer shutter speed, but you would have lost the fine detail in some clouds due to movement.

As far as the highest ISO, the reason you can't find an answer online is because there isn't one. It depends on your own noise tolerance. You have to shoot and test at all different ISO levels and decide for yourself where you want to draw the line. Also remember that a grainy picture is always better than no picture, so don't hesitate to raise the ISO into the stratosphere if needed.

[whYME]

Your picture was taken at ISO 1600 and f/13. In reality you could have shot it at 2.8, since evening in your shot is at infinity so it would all still be in focus.

I had a feeling it would be something that would make me feel stupid

As far as the highest ISO, the reason you can't find an answer online is because there isn't one. It depends on your own noise tolerance. You have to shoot and test at all different ISO levels and decide for yourself where you want to draw the line. Also remember that a grainy picture is always better than no picture, so don't hesitate to raise the ISO into the stratosphere if needed.

I hear you.
I guess I assumed based on this:

...a modern full-frame camera could go to ISO 3200 and stay clean.

that there's more of a definitive answer...

[Mordy]

You should always be on the lowest ISO possible... Your picture was taken at ISO 1600 and f/13. In reality you could have shot it at 2.8, since evening in your shot is at infinity so it would all still be in focus. Had you done that, you could have dropped your ISO by a corresponding 4.5 stops to below 100.

You could have also used a longer shutter speed, but you would have lost the fine detail in some clouds due to movement.

As far as the highest ISO, the reason you can't find an answer online is because there isn't one. It depends on your own noise tolerance. You have to shoot and test at all different ISO levels and decide for yourself where you want to draw the line. Also remember that a grainy picture is always better than no picture, so don't hesitate to raise the ISO into the stratosphere if needed.

Something interesting to add to this, from a very technical perspective (note, not for the faint of technical jargon heart). SF, I hope you don't mind if I chime in here as this is a topic I've actually taught in a workshop before, and I personally find it fascinating.

ISO values on your digital camera are more-or-less fake. Back in the days of shooting on actual 35mm film, stock was rated with an ASA number that corresponded to the light sensitivity of it. ASA 400, for example, exposed brighter looking images than ASA 100, but at the cost of slightly more grain and noise in the image. If shooting outdoors, a photographer would choose ASA 100, because there was plenty of light and it would yield the most noise-free crisp images versus the higher speed ones, even though the higher speed ones could technically be used both outdoors AND indoors (and would therefore seem a more worthwhile film to load if not for the degraded image quality as a result).
So properly exposing an image is a balance of the aperture, shutter speed and film speed, as I'm sure SF has mentioned before. Later on, due to a lack of international standards (in other countries, film speed was called DIN and had different numbers, which totally confused everyone), they made an international standard of light sensitivity numbers called ISO. Now, no matter where in the world you are buying film, your exposure math will be consistant (f/stop, shutter, ISO). When cameras went digital, there was no such thing as "film speed" anymore. There is no film. Things had the potential to get confusing again.

A digital sensor has a certain natural sensitivity to light. This can be turned up or down using a combination of analog or digital gain values, much like the volume adjustment of an audio player. You can turn the volume down lower than the natural level, and it will be very quiet, or you can boost it up high and get a lot of background noise amplified with it. Some video cameras let you adjust this value in dB increments. But for photography, we need to adhere to the ISO number standards for consistency, so they calculate how much gain it would take to emulate a particular ISO film speed, and build that into the software of the camera. Now, you have NO IDEA what the gain of the camera actually is, all you know is what ISO equivalent you are set to.

Some cameras with larger photosites have a lot of light sensitivity. Let's say, a 5D's native sensitivity would be around the equivalent of ISO 800 (making up numbers, but I wouldn't be surprised). When you set the camera to ISO 100, you are just turning down the natural gain from the sensor. You will get noise as you go higher than that (ISO 3200, etc) but lower than that your image will be relatively clean. That is, ISO 100, 200, 320, 400, etc, should be all be more-or-less identical! (they're not necessarily, but I'll get to why later) But now let's take a sensor with smaller photosites, like a Nikon N1, which let's say has a native sensitivity equivalent of ISO 200. That means even at a setting of 400, you'll get some noise. At ISO 1250, it will be even worse than the 5D would be because it is applying even MORE gain to reach that equivalent amount of sensitivity.

Now, here's where it gets even MORE interesting. If you know your cameras actual native ISO, You can work around that as your base number. In many situations, you won't really be getting a cleaner image by going lower than that, because the negative gain is fake and being applied after your sensor has acquired the information for the photo. In some cases (especially in video), the negative gain can actually lose some of the fine detail in the image!

On the Canon Rebel T2i, I remember experimenting with intermediate ISOs by using Magic Lantern to manually dial in ISO numbers that weren't accessible from the menu. I was surprised to find that ISO 640, for example, had less digital noise than ISO 400. Doing some research online showed that this was believed to be a more native value for the sensor! What was happening, is that a negative gain would be applied to bring it down to 320, which was an easy multiple off the native 640 (or something like that), than a digital gain applied to bring it up to an even 400. The result was noisier than being at a higher 640.

In a nutshell, SF's recommendation to keep the ISO as low as possible is a simple way to make sure your photos come out clean. But in the digital age, it may be somewhat of an oversimplification. Sometimes, in some rare situations, a perfect value that has very little gain (positive or negative applied) will give better results than a lower one!

[Mordy]

I realize that this "explanation" may have a negative effect in which it confuses more people than it helps. But if any of you are feeling science-y, I hope I made it clear!

[jaywhy]

Very cool!

[Mordy]

Also, yet another reason I hate "equivalency" terms in photography. Like when you buy a lens for a crop camera and it says "35mm equivalent" field of view values. Please. What if you aren't coming from 35mm photography? What if you shot medium or large format? Or if you (like me) come from the cinema world, where "full frame" s35 film is APS-C sized.

I wish we could just refer to everything as what it is. I know what a 50mm looks like on my crop sensor. Knowing what ISO 400 "equivalence" is on my camera is useful, but I really wish they'd also tell me what kind of gain I'm applying to get there. At least it should be an option in the camera!

[mek]

https://www.yahoo.com/travel/watch-time-lapse-video-showcases-california-night-93817089552.html

Just wow

[noturbizniss]

Bought a vello wireless receiver and it says to attach the receiver to the hot shoe or an accessory shoe if it's in use.  Googling reveals that an accessory shoe is a place to mount accessories when flash is in use.  Not quite sure what the accessory shoe would mount to or how? Any suggestions for one to get and better explanation for what it is?

[Something Fishy]

Bought a vello wireless receiver and it says to attach the receiver to the hot shoe or an accessory shoe if it's in use.  Googling reveals that an accessory shoe is a place to mount accessories when flash is in use.  Not quite sure what the accessory shoe would mount to or how? Any suggestions for one to get and better explanation for what it is?

It means a little female shoe-like accessory that goes into your camera strap. Holds shoe-mount accessories what the real shoe is in use.