Does the shutter speed and focal length rule of thumb apply to cropped sensor cameras?

Question

So, the rule of thumb for shutter speed is that it shouldn't be less than 1 / focal length. Well, that's straight forward on full frame cameras, but what about cropped sensor cameras? Is it going to be 1 / equivalent focal length? By equivalent focal length, I mean original focal length × crop factor.

My guess is: no, it's just 1 / focal length, cause the lens's focal length didn't physically change.

Asked by Akram Mellice

Answer

According to this Wikipedia article on the secondary effects of crop sensors:

The old rule of thumb that shutter speed should be at least equal to focal length for hand-holding will work equivalently if the actual focal length is multiplied by the FLM [focal length multiplier] first before applying the rule.

So, yes, use the 35mm equivalent focal length as your reference for minimum shutter speed.

Answered by John Rygielski

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Is there a linear relationship between shutter speed and speed of subject to freeze motion?

Question

Is there a calculation that I can do that will calculate the required shutter speed if I know the speed of my subject and want to get a crisp image e.g. freeze motion?

For example if I go to a car race and focus on a particular corner, where I know the max speed of the cars - is there a calculation I can do to work out my shutter speed before I setup?

Or if I know the speed at which the Earth rotates can I devise a perfect shutter speed to freeze the moon?

Would be amazing if you could devise an optimum shutter speed per subject chart, like a shutter speed cheat-sheet?

Asked by Rob

Answer

Shutter speed can be calculated - all you have to do it calculate the time it takes the subject to move one pixel in the image.

Unsurprisingly, other people already made those calculators, there's one here and another here

I've even seen a cheat sheet like you want but I can't find it right now (I was sure I bookmarked it)

Answered by Nir

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How do I lengthen shutter speed with out washing out the picture?

Question

I read this question, and I tried some long exposure shots myself. Every one of my shots though, is washed out. How do I achieve a long shutter speed while keeping the lighting natural?

Asked by J. Walker

Answer

You still need to expose correctly! Exposure is covered in depth in this answer. What you've done is increase one leg of the exposure, by using a longer shutter speed. Now you need to decrease the overall exposure by the same amount to get back to a properly-exposed image.

So for example, if your camera's exposure meter told you to take a picture at 1/60 s, and you carried all the settings over to manual mode but changed the shutter speed to 1/4 s, you have added four stops of light to your exposure and need to remove them.

You can reduce the exposure through in-camera settings:

• lower your ISO, as long as you weren't already shooting at the lowest ISO ("for the best quality"). If you were at 200 ISO, though, you could get one stop back by lowering the ISO to 100.
• use a smaller aperture. If you were already at f/11 to get the most depth of field for your picture, or if you're using a P&S camera without good aperture control, there's not much you can do here. But if you were shooting wide open you should be able to get several stops back.

You can also try to reduce the exposure by decreasing the amount of light coming in to your lens. There are two ways to do this:

• if you're impatient, use a filter. There are several strengths of ND filters, which are rated by how many stops of light they restrict. Polarizing filters typically cut out between 1 and 2 stops of light and also have other uses, so if you just want to buy one filter, a circular polarizer might be a better value than an ND filter.
• shoot when there's less light. Either wait for a cloudy day, or shoot at dawn/dusk, or shoot at night.

Answered by drewbenn

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How can I set an exposure time over 30 seconds with a DSLR?

Question

Most DSLRs have an exposure time limit of 30 seconds. Now I'm asking myself how is it possible to create images about over 1 hour or longer, like these two:

• http://www.flickr.com/photos/froge/3899184535/
• http://www.flickr.com/photos/_belial/481126091/

(I have a Canon 60D)

Asked by Poru

Answer

Yes it is possible with all DSLRs.

The 30s limit of all non-Olympus DSLRs is for timed exposures, meaning you dial in the time ahead of time and the exposure takes up to 30s (or 60s for Olympus).

All DSLRs also have a bulb mode which you press the shutter to start the exposure and let go when you are done. This can also be done with a remote control which is highly recommended to avoid shaking the camera during the exposure.

Bulb modes also have limits but manufacturers do not all publish what it is. For Olympus and Panasonic, this is known to be 30 minutes. Some cameras can take a single exposure of several hours. Regardless of the model you are always limited to the battery-life of your camera unless you use an AC-Adapter and have somewhere to plug it in.

Digitally you can simulate extremely long exposures using Exposure Stacking which basically adds up multiple exposures to make a longer one. A lot of astro photography is done that way, just make sure that your camera does not apply Dark-Frame subtraction between shots otherwise you will have gaps in your star trails. On some cameras you can disable Dark-Frame Subtraction but not on all.

Answered by Itai

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How can I take hi-speed photos of water rockets?

Question

How can I take a picture of water rockets as they fly through the air? What settings would be best under normal daylight conditions? What is the slowest shutter speed I can use that the lighting will still look natural, but it will also capture the water trail and droplets? And what would be the best aperture so that the background is not in focus, and the main thing in focus is the rocket?

Asked by J. Walker

Answer

"Real" water rockets accelerate EXTREMELY fast. While some with restricted orifices may stagger off the launcher, anything that aims at performance accelerates faster than almost anything else you are likely to photograph. A top rocket 9by calculation and experience) accelerates at up to about 100 g !!!.

There are various shots you can take. Looking up at the rocket well above you is a fairly general shot and panning can work. Exposures and shutter speeds can easily enough be arrived at by experiment.

Getting a good shot as the rocket leaves the launcher up to say 10 to 15 feet in the air, takes care, planning and luck. Smaller aperture for better depth of field helps. Fast shutter speed can help BUT there is another way. Set camera to manual, adjust for a relatively low shutter speed - below max flash sync speed, and then add flash. Rear curtain flash is even better if you have it. Adjust flash to ambient lighting so rocket stands out when the flash operates. Good shots may be had by framing from launcher to about 15 feet pointing upwardsish from near the ground so the rear curtain flash catches the rocket sharply. You get a water trail with some blur (depending on shutter speed) and a sharp rocket IF you are lucky. Just using flash plus ambient can also be good.

An interesting point to take photographic advantage of is that a rocket which has the majority of its mass as propellant and which is not very restricted in its jet will accelerate to faster than its own exit velocity. (The rocket equation makes this clear when you look at it and plug in high Full/empty mass ratios). Using an eg 1.5 litre bottle with about 100 to 120 psi and bottle mouth as orifice and 1/3 fill (about optimum) the water will be all exhausted by about 15 feet after takeoff BUT the rocket will exceed its exhaust velocity after about 5 to 10 feet from the ground. This means that water below this point is being ejected with a downwards velocity BUT above this point the ejected water actually has a net upwards velocity. The end result is that the water plume in the air changes shape as the water exiting slows and then reverses. Above the reversal point it starts to fan into a cloud with increasing spread as the upwards velocity of the water increases with height and is spread more by th air as it hits it faster. When I first saw my photos of this I did not understand what I was seeing but it makes sense once you realise. The effect is amazing - quite unlike what you expect to see and fast enough that you don't really notice with the eye alone unless you are looking for it. So the photos are especially surprising.

I can find some photos of this effect if of interest. Quite some years ago now :-)

Also fun is a two or more photo sequence of the ascent with the photos manually stuck together. That they don't quite match due to change in perspective and angle doesn't matter. People see immediately what you've done and appreciate it for the fun effect. (I have one such pair where the rocket went to about 6,200 feet ASL - BUT it was launched from 6,000 feet ASL ;-) - highest altitude water rocket shot in NZ (I think). Have the photographer stand back some way to do this. First shot shows water plume standing maybe 20 feet in air plus some sky above and second shot overlaps and has lots of sky and cloud and rocket high above. Chances of getting rocket in the first shot is about zero but water plume is easier. Rocket in second shot is at apogee so easy.

NB - be prepared to get you and your camera deluged.

---

Added:

You could try "cheating a little" :-):

• Use a very low pressure so that the rocket comes off the off the pad more slowly, relatively. Adjust pressure to speed.

• Adjust fill %. Almost full and almost empty will produce less speed and less altitude.

• If you can adjust the orifice, use a smaller opening. Some launchers do not allow this directly - eg those that use a "launch tube". This can be overcome by inserting a movable orifice plate in th bottle that sits in the bottle during ascent up the rod and then moves into the neck once it clears the launch rod. Some place this on top of the launch rod so that the rocket collects it as it ascends. You need a restrictor that can be pressed through the rocket nozzle but which then expands / pops out / ... so it is trapped on ascent.

• Combinations of the above.

Answered by Russell McMahon

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Why does the left windmill have too many blades?

Question

Ok, check this shot out:

These are the 3 windmills in Marshfield Massachusetts. It was shot from Provincetown, MA about 35 miles away. (I wasn't out to shoot them, I was shooting Right Whales... I know, life is tough...

The shot is a pixel peeped full crop. Canon 40D body, the 24-105mm F4 lens, shot at 1/640sec at f4.0 using aperture priority. ISO 100.

What is going on with the left most windmill? It the blade at around 8pm is doubled. How did that happen?

Asked by Paul Cezanne

Answer

You're seeing the effect of a focal plane shutter (also see Wikipedia on the topic). At ¹⁄₆₄₀th of a second, the whole frame isn't exposed at once, but with a moving slit between the first and trailing shutter curtain. This catches the moving windmill in different places. Helicopter blades are the typical example here, because they often show up distorted in this way.

J. Andrzej Wrotniak has a nice detailed explanation of another possibility: slow readout of the CMOS sensor. I'm pretty sure it's the focal plane shutter in this case, though, as the given explanation there doesn't make sense in this case.

(And there's another nice example in this answer on Stack Exchange, which I mention with the caveat that the person who posted it went slightly insane with unexplained vitriol for no apparent reason and started trolling the site shortly afterwards.)

Answered by mattdm

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Do very short shutter speeds result in diffraction?

Question

I'm curious if very short exposure times (say 1/8000 or even 1/16000) would cause noticeable blur due to diffraction.

To achieve very fast shutter speeds focal-plane shutters start to close the second curtain before the first one has passed completely over the sensor.

(Illustration from wikipedia)

Is the slit between the front and the rear curtain small enough to make a noticeable impact on the image due to diffraction?

Answer

Slits don't diffract; edges do. There will always be some small amount of the image exposure that arises as the result of diffraction, whether that be from a focal plane shutter or from a leaf shutter. The questions, then, are: how much of a contribution to the overall exposure does diffracted light make; and is there enough angular displacement for that diffraction to matter?

On an APS-C format camera with a 16mm x 24mm sensor and a vertically-travelling focal plane shutter whose curtains traverse the sensor in 1/250s (yielding an expected x-sync speed of 1/200s, allowing for flash duration), when the shutter speed is set to 1/8000s, the minimum gap between curtains will be 0.5mm, which is relatively enormous compared to the wavelengths of the light passing between the curtains. There will be some diffraction, of course, but the degree of interference over most of the slit width will be negligible. The "clear" exposure, the area over which the effects of reinforcement and cancellation have an insignificant effect on the overall magnitude of the incident light, will significantly outweigh the diffraction fringes around the edges of the curtains.

Focal plane shutters, too, are called that because they are very near the focal plane. There isn't a whole lot of room between the shutter curtains and the sensor (or film). The areas of the diffracted light that have significant reinforcement will not be displaced laterally very far, given that they don't have a lot of room to spread out and get comfortable. The distance between sensels on the sensor is much smaller than the width of the shutter slit, being around 7 microns these days, but that is still large relative to the wavelength of light -- light would need to spread out quite a bit before the first few bands of reinforced light (the ones having enough amplitude to affect the overall exposure) started to impinge significantly on neighboring sensels.

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What are the physical limits of a mechanical shutter?

Question

I've recently found myself shooting a lot of photos on the maximum speed that my camera (a Canon 600D) allows (1/4000). This is quite extreme when thinking about mechanical movements, so I assumed that the digital shutter must be used at that speed. What is the maximum speed that is possible for the mechanical movements and where does the electronic shutter kick in if at all?

P.S. My brain also tells me that there is a possibility that with the amount of light available and the speed being so high that the entire sensor might not actually have to be fully exposed( at one time) to the light source but that a small slit between curtain 1 and 2 should be sufficient.

Answer

The Canon 600D uses a mechanical shutter, and it does indeed go up to 1/4000th rate. There is no "electronic" shutter in Canon DSLR's that I know of. You pretty much nailed it on the head with your 'ps'...the two shutter curtains race over the sensor with a tiny slit (see 'Focal plane shutter, high speed' figure), with the second curtain a minuscule fraction of a second behind the first curtain.

As for maximum speed, I can't say for sure, but pretty high. There are many DSLR cameras that have a 1/8000th or 1/10000th shutter rate, usually "pro grade" models. The high maximum speed of this type of shutter is one of its strengths (leaf shutters, for example, tend to be limited to about 1/500th.)

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Why am I getting a slow shutter speed with Child mode on Nikon D3100

Question

I am just starting out with my Nikon D3100 and taking pictures of my kids who never seem to sit still. I thought that Child mode would be the most appropriate mode to do this with but I seem to be getting slower shutter speeds than I would have expected and consequently the pictures come out blurry when inside with available light. The settings I have are:

• Child Mode
• Flash disabled - because I only have the built in flash and it seems to really blow out the kids faces when it's on.
• Aperture automatically set to largest value (in this case, f2.8)
• ISO automatically set to 400.
• Shutter speed automatically set to 1/20.

My thought was in Child mode I would have expected there to be a lower bound on shutter speed, say 1/50 or so, and let the camera bump up the auto ISO to 1600. Then, if the camera hit the ISO limit, it could start backing down the shutter speed to get the correct exposure, but that doesn't seem to be what is happening to me.

Answer

The manual describes child mode like this:

Use for snapshots of children. Clothing and background details are vividly rendered, while skin tones remain soft and natural.

So, while it probably affects the exposure program as well, from Nikon's own words the main concern seems to be with color rendering. Whatever effect this might have have on the automatically-selected shutter and aperture speed is "inside the black box". This is one reason I'm not fond of scene modes for learning. They're for people who want to avoid thinking about photography and just take some pictures. This doesn't really help ease you in to advanced knowledge in any way — it just gets annoying.

Since you're clearly thinking about how you want the shutter speed to be, I think it's time to abandon "child mode".

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Why do I get horizontal grey bar with flash at shutter speeds slower than max sync speed?

Question

I'm a total newbie to flash photography. And I just trying to do some test shooting with Canon Speedlite 580 EXII using my 7D.

I saw on the user manual that the maximum sync speed is 1/250 sec.

However I got the horizontal grey bar on shutter speed 1/200 and even 1/160 !

I would like to know what I did wrong... PLEASE HELP ME OUT !

See the images here:

Thank you!

/////////////////////////////////////////////////////////

I have this issue with Cactus V5, as well as pocket wizard plus II, With Pocketwizard Mini TT1 and Flex TT5 I dont have that issue maybe because of the high speed sync support ?

Thank you for all the helps !!!

Answer

The 580EX should be fired in perfect sync with the 7D. Definitely when below sync speed. You seem to have a lag in your system here so the flash fires a fraction of a second after the 2nd curtain starts to close.

UPDATE - just noticed that the flash is actually mounted on the light stand and shoots through the umbrella - and it looks like you are using a non TTL wireless trigger to fire the flash. In this case it is possible that the radio trigger introduces that lag.

UPDATE 2: You can try setting the trigger to 1st curtain if it is set to 2nd curtain and it may help overcoming this lag with the slower shutter speed (say, 1/160).

I wonder why you don't use the built in remote flash controller in the 7D? The 580EXII+7D are a (almost*) perfect match in this sense.

(*) almost, b/c it does not support high-speed sync (HSS) mode in wireless mode.

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What is the highest shutter speed in which the shutter is at some point completely open?

Question

Specifically, for my Nikon D7000, but also in general. Is this shutter speed basically going to be the same shutter speed as the fastest flash sync speed, or the flash sync speed more affected by things like inaccuracy in when the flash is actually firing / duration of the flash pulse itself?

Answer

In essence, the flash sync speed is the highest speed at which both shutter curtains are open at the same time. At higher speeds, the second shutter starts to close before the first curtain is completely open. So for practical purposes, sync speed equals what you are asking for.

There is probably some minimal slop factor involved which allows for a very slight delay in firing the flash (it takes a non-zero amount of time for the flash to pump out all its light at max power, but this should be in the region of 1/1000 of a second or so), but this will not be much. It can be an issue in multi-flash setups though, where you cannot actually use the max sync speed because the slave flashes are just a little bit delayed and won't fire until the second curtain has started to close.

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How do different aperture and shutter settings affect a photo with the same overall exposure?

Question

Ok, here's my doubt. Suppose I want to get a certain exposure for an image. Keeping the ISO constant, there are two tentative possibilities here:

1. Put the camera at f 1.4 (say) and at 1/1600 shutter speed (suppose).
2. Put aperture at f 8.0 (say) and shutter speed at 1/50 (suppose).

Both would get me the exact same exposure. Yes, for the latter, I may have to use a tripod. But the question being, what would be the difference in the image thus obtained? I can fairly interchange the settings for the same shot (theoretically). Or can't I?

Answer

Different shutter speeds have an obvious different effect: more motion-blur. (That includes both subject motion and blur from any motion of the camera itself.)

Different apertures also produce different results; most notably that depth of field increases as you stop down. So, f/8 gives you a much deeper in-focus area than f/1.8. This effect is lessened on a smaller sensor (or, if for some reason you just crop out the center part of the image and blow it up), to the point where it's basically a non-factor on most point & shoot cameras.

But there are other effects of changing as well: lens sharpness, contrast, and vignetting characteristics change, usually improving significantly when you stop down a bit. (For a certain look, though, that technical improvement may not, in fact, be what you want.)

That's assuming perfect reciprocity — the idea that aperture and shutter speed really are perfectly interchangeable for exposure. With film that's not strictly true as you get to extremes — see this question on reciprocity failure. But for digital, it's not meaningfully a factor.

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What is the shutter speed needed to stop motion?

Question

I find that taking pictures where the subject is in motion (people, pets, toy helicopters) I get a blur where there is movement.

On the other hand I see images of a drop of water in free fall in perfect clarity.

How fast does the shutter need to be to capture action in motion with perfect crisp clarity?

For example I want to catch a dog shaking himself dry after a swim and not get a bury mess but to see the hairs flying and water frozen in the air as it flies off the dogs fur and makes a giant mist around the dog.

Answer

While you can get some freezing with speeds around 1/300 (see the first photo below), I would recommend going with faster shutter speeds if you want to take shots of water drops falling or moving away from wet dogs.

One thing to keep in mind is that most flashes have a limit on their sync speed, which means that the use of flash will limit your fastest shutter time available.

• Example 1: 1/320 speed, no flash:

(as you see there's still blur on the water and a flash, even if able to reach the dog, wouldn't make much a difference if it wasn't able to go faster than 1/320)

• Example 2: 1/1300 s, using the internal flash of a Panasonic FZ18 and the ambient kitchen light:

Here a smaller aperture and the ambient light allowed for a slight slower speed, but the shot is sharp enough for me.

• Example 3: 1/1600 s, using the internal flash of a Panasonic FZ18, no ambient light (shot in the dark):

Here the speed was enough to freeze the drop and the flash was set stronger enough to provide the needed reflections on the background (since there was no ambient light).

Finally, if you are into capturing water drops don't miss John Cavan's very good post on the subject - Catching the Elusive Water Drop

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What shutter speed to use when shooting video?

Question

My camera is Canon 60D and I will be using it to shoot a short parkour video, that means:

• a lot of motion, moving subjects, moving camera
• focal length usually from 24 mm to 75 mm, but there will also be a scenes shot at 200 mm
• a lot will be shot in 1080 at 24 fps (or should I use 25 fps or 30 fps ?)
• some scenes will be shot in 720 at 60 fps

Accessories:

• I do have a steadicam
• I have got 1.8 lenses (24 f/1.8, 35 f/1.8, 50 f/1.8) so I can use low f-stops.

Questions:

• What shutter speed should I use? I have read that it should be double the FPS. Why so? What if I break this rule?
• When I use low shutter speeds (1/120) and I'm shooting during the day, I need f-stop at around f/12. Does this mean that my f/1.8 lens are useless in this case and I can use any bundle f/4 lenses instead?
• Any tips on improving whatever I wrote above?

Answer

The reason that many people will recommend to shoot at double your framerate is because then the 'shutter angle' is 180 degrees.

This is back from when film cameras were used. To cover the negatives whilst the next frame was 'wound on', a disc would spin, blocking the light as the negative moved. When the negative was in place, this disc would spin open again. Wikipedia has a good animation of this here.

The amount of covering the disc provides and the framerate give this 180 degrees that is as close as you get to a 'standard' in filmmaking. For further reading on this (or a better explanation!) I'd suggest looking over here.

As for a specific recommendation of shutter speed, it depends on the look you want. For example, some action films (using these as an example because they have lots of movement within the frame) will use a very fast shutter speed for sharp images, but being professional films they are still shooting at a framerate (or 23.976). Others will use the slowest they can get away with, and this will give them lots of motion blur within the shot. A good film that shows examples of both of these is The Bourne Identity.

TL;DR - It's a creative decision.

As for the problem with your F-stops, this is (unfortunately, because you have some real nice lenses) just something you're going to have to live with. Consider whether a slow shutter speed is absolutely necessary for these scenes. Using a faster one could allow you to use your f1.8. Also, depending on the camera you're shooting on, sometimes setting it to 'Auto ISO' can actually let the camera reduce the ISO below the minimum (100, normally) using some metadata hacks or something. (This may just be for stills, though!)

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How to photograph panning with a point and shoot camera?

Question

I have recently learnt about panning photography on the internet and I was curious about capturing one myself,

But as an amateur I just own a Point and shoot camera,

I have experimented through it thoroughly and the only scene mode with longer shutter speed is Fireworks mode(4s),

But when I used this mode to take a panning photograph, all I got was an Over Exposed image,

How can I take a panning photograph with a point and shoot camera?

Answer

You still need to expose your photograph correctly. So if you're taking a panning photograph in bright light you have to either use a very narrow aperture or a filter, or both. Of course with a P&S camera, both those are difficult: you may have no control over the aperture at all, and there may be no easy way to attach a filter. If that's the case, you'll have to take your panning photographs in darker lighting.

You don't need ultra-long shutter speeds like 4 seconds, though: my picture here was only 1/15 of a second. If you are closer to your subject and it's moving faster, you can probably get away with an even faster shutter speed.

One thing you could try, although I've never tried this and it may be too awkward to pan steadily, is hold your sunglasses in front of the lens as you pan, as a makeshift neutral density filter.

Finally, if you try taking panning photographs in darker light in order to achieve the longer shutter speeds, your camera will probably increase its ISO to prevent camera shake, which is the opposite of what you want (since panning is, in one sense, controlled camera shake). If your camera has a mode that lets you force the ISO to its lowest value, you probably want to use that mode.

Of course, I hope you've also read this answer -- maybe all you need to do with your camera is leave it in Auto mode, zoom in as far as you can, and take pictures of nearby, fast-moving objects.

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What shutter speeds should I use for cars in motion and slow-sync flash?

Question

I'm an amateur with a Canon EOS 400D/Rebel xti.

I know that any given shot requires it's own recipe for shutter speed, ISO and aperture, and I'm aware of the triad of those three.

I typically shoot in aperture priority mode, but sometimes I want to deliberately get a certain amount of movement in a shot, so go for shutter priority mode.

What is a good starting-point shutter speed when I want to capture the following:

Motion - For example, when taking a picture of a moving car, wanting to get the wheels looking like they're spinning, and the background motion-blurred, but with a good chance of keeping the car itself sharp.

"Slow-synchro" flash - For example at an indoor dinner or (darker still) disco, where you want the subject to be illuminated by the flash and quite sharp, but where the shutter is still open long enough to capture the background lighting.

Thanks in advance.

Answer

Motion

It depends on a few variables eg, speed of subject / distance to subjects / focal length / speed of moving camera (for panning shots) etc.

But I would suggest just start at 1/20th second, take a test shot, then adjust as needed. Simple!

"Slow-syncro" flash

Well, now you're adding a fourth factor in the exposure with the flash (flash power / distance etc.).

However, assuming you're using the built-in flash or a speedlite that supports ETTL... I would allow for slightly longer shutter speeds, since the flash will freeze the main subject and you probably want long light trails for artistic effect.

1 second:

1/10 of a second:

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Do fluorescent lighting and shutter speed create a problem with color cast?

Question

I took a bunch of photos at my son's martial arts club using a D90 with a 50mm F1.8. The club is lit with overhead fluorescent lighting, and I was getting some weird results where some shots are "white", others have an "orange cast", and still others are partly white and partly orange in the same shot.

I suspect it has to do with the combination of the frequency of the light flicker and with the camera shutter speed. Here is a sequence of 3 shots that show the problem. The shots were taken with 1/500s at F2 and ISO-800 and with Auto-WB.

First shot ("white/normal"):

Second shot ("orange cast" at top):

Third shot ("orange cast" at bottom):

These were taken in burst mode within a second of each other.

Can anybody tell me what is going on? And, how I can avoid this?

Answer

Fluorescent lights can flicker at twice the frequency of the current feeding them, which implies an entire cycle of the flicker will take between 1/100 and 1/120 second. During each cycle the light's intensity and its color temperature can change. Thus, if you're using a shutter speed of 1/100 second or faster, you might observe exactly these phenomena: your photos make an interesting document of them, especially the bottom photo.

Details appear deep within a good Wikipedia article on fluorescent lamps under the heading "Flicker Problems". The article references "The Feral Photographer" blog which gives a brief (simplified) explanation from a digital photographer's perspective.

For sports photography indoors you need a short exposure time to freeze the action. Consider flash options if they are possible. Very short exposures (down to 1/4000 second typically) can be achieved with HSS flashes. To an extent you can adjust the color balance, especially when you're shooting RAW images, but that's going to be tricky during the color transition.

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How to shoot sharp “landscapes” with a point and shoot camera?

Question

So, I have been told in a thread here previously that the minimum aperture (F8) on my point and shoot camera can cause diffraction and result in losing details of the subject if too many things are in focus. Fine.

Now, if I have to shoot a far away landscape scene and I choose an aperture of (F5), it won't result in a sharp picture, and I can't use F8! :(

See this:

Now is it possible that I use the aperture as low as possible and increase the shutter speed and thus get the same results as I would be getting from aperture F8 (with a low shutter speed)?

What can be the possible combinations?
I mean with F3, speed 1/500?
Of course one way is to go on trying each and every possible combination, but if I get some starting points, I think it'll make my life easier.

Answer

On your sample photo, fog or smoke in the air seems to be the reason why further landscape is not sharp. Nothing in your camera can help against that. Try coming back at another time to see if the air is more clear. Above a city with polluted air, this might never happen.

A wider aperture with faster shutter time will result in equivalent exposure, but depth of field will be smaller, because it is determined only by the large aperture. Opening up all the way is bad for sharpness because most lenses are getting sharper when aperture is smaller than maximum by a stop or two (unless you hit diffraction limit).

To get maximum depth of field, you should focus to something far away to ensure that you are covering hyperfocal distance. You might also still decide to use f/8, because you might prefer even overall sharpness to better sharpness at smaller range. In technical side of photography, compromises have to be made quite often.

Another thing you could try is sharpening in post processing (e.g. using Unsharp mask).

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What are the benefits and costs of an image stabilized, slower lens vs a non-IS faster lens?

Question

I am going thru a trade off decision between a 24-70 f2.8 lens and a 24-105 f4 IS lens from Canon. My dilemma is that the 24-105 focal length better matches my needs, but the f2.8 would occasionally be nice indoors.

What is the board's practical experience with IS? When comparing, at the same ISO and focal length, this trade off, one can observe that at f2.8 and 1/60th, would equate to 1/30th at f/4. In this example, is it practically possible to achieve blur free results with an IS equipped lens hand-held at 1/30th? (edit: this relates to the 24-70 range both lenses share)

Since it is fairly easy to achieve blur free images with nearly any lens at 1/60th and above, how does 1/30th with IS compare? Do you end up with sharp images at these speeds?

Answer

I can speak from actual hands-on experience here, for a change :) I owned both simultaneously; I kept the 24-105 and sold the 24-70. For ME, the benefits of IS outweighed the benefits of f/2.8 and the much better lens-hood of the 24-70. Your mileage may vary though.

The 24-105 IS allows me to shoot at 1/10 second at 105mm and expect a sharp photo. Or I can go to 1/5 and take three shots of every motive, and expect at least one to be sharp. With the 24-70 I'd have to live by the 1/focal length rule, exceeding 1/50 at 70mm would be iffy. The slow shutter speeds with the 24-105 lets me stop down quite a bit for depth of field for similar exposure as the 24-70 would give me at f/2.8. Extra depth of field is a Good Thing most of the time - I use the full-frame 1DsII so I don't get any free DOF from a sensor crop.

This, of course, only applies to stationary subjects. Which, fortunately, is what I shoot with the lens. In my experience, for moving subjects, the one extra stop that f/2.8 gives over f/4 is neither here nor there; if f/4 isn't fast enough then f/2.8 probably won't really cut it either. For low-light photography of moving subjects I take out the 85mm f/1.2L which is a portable black hole which will suck up any light that is present in the room. Candlelight is more than enough.

That said... the 24-70 was a more fun lens to use than the 24-105. It had a certain something. The 24-105 is a staid, practical, useful lens without a poetic bone in its body. Ho hum. The plain sister with the good personality, if you will. But it's the lens I use the most.

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Is burst rate higher in RAW mode?

Question

I own a Nikon D5000 and the Wikipedia page says that :

Continuous shooting 4 frame/s for 67 Large Fine JPEG or 11 RAW frames

Does this mean that keeping the camera in NEF (RAW) mode increases the frame rate?

Answer

The rate is 4 frames per second in either case. The difference is in how long it can keep it up — 67 JPEG files of the "large fine" quality level, or 11 RAW frames. That's because it can basically keep going as long as it has RAM to buffer the files, and has to slow down as soon as it has to actually start saving to relatively pokey flash memory. The limit is lower for RAW files simply because they're larger and consume more of the buffer.

There's some notes on this in dpreview's D5000 article, where they confirm the rate of 4.0 fps, and in their testing get 100 Large-Fine JPEGs and 11 RAW files. The difference in the number of JPEGs probably comes down to the compressiblity of their test scene. They also note a performance of 2.6 fps once the buffer is full (with either file type), and a limit of just five shots with RAW+JPEG. Turning on Active D-Lighting (which requires more processing per frame) also slows things down.

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