How can achieve better low-light shots?

[SergeTheBlerge]

Been working with my Canon Rebel T6i for a decent while now and while I know it's not renowned for it low light quality, even when shooting in JPEG, many of my low light images come out in significant substandard quality and I'm thinking it's just my settings. Here is an example of a photo I shot just yesterday and while it did look pretty clean on my LCD, it showed its true colors when I booted it up on my laptop, especially when looking at the train's side itself.
I've been using mostly exclusively Manual mode. The specs of this shot are f/8, exposure 1/160, ISO 12800, and focal length 32mm using my standard 18 - 55mm lens.

Should I be setting my camera to something else? When I'm in low light, my main priority is simply to get enough light into the camera so I'll actually get something visible. While in Manual mode I set my camera to the landscape setting and use all 19 points of focus featured. No flash.
Any help is much appreciated. thanks!


[IMG][/IMG]

[Manfred M]

Two things jump out at me Sergio:

1. The image is soft, so I suspect that you are hand holding? All my low light work is done on a sturdy tripod. That lets me do long, low ISO exposures. A lot of my exposures are with the lens wide open to maximize light gathering; f/8 is way to slow if you are hand holding.

2. You may be shooting on manual, but your exposure if off. Try bracketing your shots a couple of stops; the whole side of the train car is significantly underexposed. Frankly, for a shot like this I will often take several exposures, varying the shutter speed, but not the aperture so that the DoF does not change and then I will blend them in Photoshop, bringing out the properly exposed side of the railway car and then melding that with the rest of the image / sky.

[Shadowman]

Hi Sergio,

For a still subject start off using a tripod, shoot P Mode and see what the camera chooses for settings. Next, define how you want to capture the image, do you want sharpness throughout, then stick with the f/8 you used for this capture, lower ISO to 100, and let the camera choose shutter speed. That's a good starting point for subject's without movement. When you say manual mode, I assume you are talking about manual focus?

[dem]

The ISO is far too high. I would drop it to ISO 1600 or lower and shot at a slower shutter speed from a tripod.

I would also consider shooting raw and taking a few images at even slower shutter speed to expose for the shadows. It is then possible to combine several images in one in post processing (google HDR).

One thing for sure - tripod is a must.

[Mike Buckley]

It's very difficult at the small size of the image file to know what you are disappointed in, but my guess is that you are concerned about the noise.

Regardless of the situation, bear in mind that to achieve the least amount of noise, the most important issue mostly because you are in complete control of it is to get the most "accurate" exposure; the less accurate, the more noise. Next in line is the ISO value; the higher the ISO, the more noise if indeed noise would exist. Last, the areas of an image that are not in focus are more likely to display noise (though I recognize that this issue does not apply to your image).

As for achieving "accurate" exposure, always review the histogram after capturing a scene such as this one. If it is not ideally exposed, change the exposure, capture the scene again and recheck your new histogram. The exposure in this image at least as indicated by its current histogram is reasonably accurate but only so long as you are willing to accept the blown highlights. If you begin with an underexposed image and then improve exposure during post-processing, you are most likely to also increase the noise in the shadow areas.

As for using the lowest ISO value, the most effective way to do that is to use a tripod and to set the camera's ISO to its base ISO. If you have to accept the compromise of hand holding the camera in a low-light scene such as this one, shoot at an exposure setting that has a shutter speed that is fast enough to allow hand holding the camera and an aperture that is the largest setting that still allows everything in the scene to be in focus.

You could have used an aperture set at least to f/4 and probably f/2.8 and still kept everything in focus. Using f/4 would have been two more stops of light; f/2.8 would have been three more stops. If you had done that, you would have lowered your ISO to 3200 at f/4 and 1600 at f/2.8, an entire world of improvement when it comes to limiting noise.

You could have also used a shutter speed of about 1/60 and perhaps even 1/30 and would have still been able to hold your camera steady enough. That would have been more than one stop more light at 1/60 and more than two stops at 1/30. If doing that while using f/2.8, you would have then lowered your ISO to less than 800 at 1/60 and less than 400 at 1/30. It's possible and even likely that at ISO 800 or lower, there would have been absolutely no noise (though I admit that I have no personal experience using your camera model).

As for achieving sharp focus throughout, I would use single-point focusing on a scene like this one. I see no advantage to using more than one focus point. Having said that, your image seems to be sharp throughout, at least when viewed at this small size.

You mentioned that you don't see the noise on your camera's LCD. Be sure to magnify the captured image in the LCD. If noise is present, you'll see it when the image is magnified. Once you see that the noise is indeed present, consider all of the above, especially the possibility of using a larger aperture and slower shutter speed that would allow you to use a lower ISO value.

[SergeTheBlerge]

Two things jump out at me Sergio:

1. The image is soft, so I suspect that you are hand holding? All my low light work is done on a sturdy tripod. That lets me do long, low ISO exposures. A lot of my exposures are with the lens wide open to maximize light gathering; f/8 is way to slow if you are hand holding.

2. You may be shooting on manual, but your exposure if off. Try bracketing your shots a couple of stops; the whole side of the train car is significantly underexposed. Frankly, for a shot like this I will often take several exposures, varying the shutter speed, but not the aperture so that the DoF does not change and then I will blend them in Photoshop, bringing out the properly exposed side of the railway car and then melding that with the rest of the image / sky.

No, I didn't have my tripod with me. I did handhold although this shot was taken from the inside of my car parked alongside, hence I try to lean my elbow against the door to get as stable as possible.
When you say long ISO exposures are you talking about basically setting the shutter speed much slower? On a tripod, what shutter speed would you recommend? A higher F stop?
I'm sorry but I don't know what you mean by "bracketing your shots a couple of stops." I'm assuming you're talking about F stops. The whole side of the train is underexposed, yes, but as are the bushes and branches to the right of the train. Basically anywhere where there is a solid color is extremely grainy.

Keep in mind I don't have photoshop. As of right now I'm looking into Lightroom 6 as it's the most affordable. I just want to get these shots as clean as possible before I put them through editing.

Thanks for the reply!

[SergeTheBlerge]

Hi Sergio,

For a still subject start off using a tripod, shoot P Mode and see what the camera chooses for settings. Next, define how you want to capture the image, do you want sharpness throughout, then stick with the f/8 you used for this capture, lower ISO to 100, and let the camera choose shutter speed. That's a good starting point for subject's without movement. When you say manual mode, I assume you are talking about manual focus?

Yes I'm using manual mode on the camera, but the lens I always have set to Auto.

[SergeTheBlerge]

The ISO is far too high. I would drop it to ISO 1600 or lower and shot at a slower shutter speed from a tripod.

I would also consider shooting raw and taking a few images at even slower shutter speed to expose for the shadows. It is then possible to combine several images in one in post processing (google HDR).

One thing for sure - tripod is a must.

As of now I have my camera on the RAW + JPEG feature, so I get both. I've never used google HDR so have to look into it. thanks

[Mike Buckley]

1. The image is soft, so I suspect that you are hand holding?

I don't think it's possible to tell at this small image size whether the full-size image is too soft. It's very possible that the proper sharpening techniques were not used when downsizing the image for display here, especially considering the OP's understandable but basic questions.

[Dave Humphries]

Hi Sergio,

To pick up on another aspect of technique ...

While in Manual mode I set my camera to the landscape setting and use all 19 points of focus featured.

Why try to use all 19 focus points?
Using more will not work better, even in low light.
The extra ones will be (effectively randomly) all over the scene, trying to focus at different distances, which the DoF for aperture chosen, may not be able to encompass - leading the camera to decide to focus somewhere that's not the primary subject. This may only add to perceived softness issues.

You also need to know that the AF will work on areas of high contrast edges, so while you might consider the railroad coach to be the subject, it is dark and low contrast, so the AF (given free reign) will prefer those tree branches against the sky, some distance behind your subject. Combine this with too little DoF and it can all add to a subject softness problem.

If you had used the single, central focus point, aimed it to focus on say, the white railings at coach end, then 'locked' it and recomposed for the required composition, the result might have been better.

These principles hold true even if it wasn't absolutely relevant in this example (due to a variety of other factors).

HTH, Dave

[SergeTheBlerge]

As for achieving "accurate" exposure, always review the histogram after capturing a scene such as this one. If it is not ideally exposed, change the exposure, capture the scene again and recheck your new histogram. The exposure in this image is reasonably accurate but only so long as you are willing to accept the blown highlights.

As for using the lowest ISO value, the most effective way to do that is to use a tripod and to set the camera's ISO to its base ISO. If you have to accept the compromise of hand holding the camera in a low-light scene such as this one, shoot at an exposure setting that has a shutter speed that is fast enough to allow hand holding the camera and an aperture that is the largest setting that still allows everything in the scene to be in focus.

You could have used an aperture set at least to f/4 and probably f/2.8 and still kept everything in focus. Using f/4 would have been two more stops of light; f/2.8 would have been three more stops. If you had done that, you would have lowered your ISO to 3200 at f/4 and 1600 at f/2.8, an entire world of improvement when it comes to limiting noise.

You could have also used a shutter speed of about 1/60 and perhaps even 1/30 and would have still been able to hold your camera steady enough. That would have been more than one stop more light at 1/60 and more than two stops at 1/30. If doing that while using f/2.8, you would have then lowered your ISO to less than 800 at 1/60 and less than 400 at 1/30. It's possible and even likely that at ISO 800 or lower, there would have been absolutely no noise (though I admit that I have no personal experience using your camera model).

As for achieving sharp focus throughout, I would use single-point focusing on a scene like this one. I see no advantage to using more than one focus point. Having said that, your image seems to be sharp throughout, at least when viewed at this small size.

You mentioned that you don't see the noise on your camera's LCD. Be sure to magnify the captured image in the LCD. If noise is present, you'll see it when the image is magnified. Once you see that the noise is indeed present, consider all of the above, especially the possibility of using a larger aperture and slower shutter speed that would allow you to use a lower ISO value.

I've honestly never really checked the histogram because I'm not entirely sure how to read it accurately. As for the f-stops, I cannot go as low as 2.8 or even 3 because my lens only allows down to 4. I'd have to purchase a new lens and as of now I'm simply trying to get as proficient as possible with the camera itself.

I use all 19 points only because I just FIGURED it would do the best job at making the entire scene as sharp as possible. My camera also can mainly focus on any ONE point I set it to manually. I'll try this next time and see how it works out, especially in low light.

thanks a bunch!

[Manfred M]

No, I didn't have my tripod with me. I did handhold although this shot was taken from the inside of my car parked alongside, hence I try to lean my elbow against the door to get as stable as possible.
When you say long ISO exposures are you talking about basically setting the shutter speed much slower? On a tripod, what shutter speed would you recommend? A higher F stop?
I'm sorry but I don't know what you mean by "bracketing your shots a couple of stops." I'm assuming you're talking about F stops. The whole side of the train is underexposed, yes, but as are the bushes and branches to the right of the train. Basically anywhere where there is a solid color is extremely grainy.

Keep in mind I don't have photoshop. As of right now I'm looking into Lightroom 6 as it's the most affordable. I just want to get these shots as clean as possible before I put them through editing.

Thanks for the reply!

When I say "long, low ISO", I tend to shoot at my camera's base ISO as much as possible. I don't know the noise characteristics of your camera at all, but suspect you are going to have issues above ISO 800.

Exposure bracketing simply means taking the same shot, but varying the exposure +/- a few stops. According to the EXIF data, you shot this at 1/80th sec. I would have probably kept the ISO and aperture the same and in addition to the 1/80th, would have taken one shot at 1/160th and shots at 1/40th, 1/20th and 1/10th. Notice I would have changed the shutter speed only because you don't want changes to the aperture as that will change the depth of field.

Lightroom will not let you work in layers, so you will be limited to using a single exposure. The HDR function of Lightroom would let you combine bracketed shots and give you something that you cannot get out of a single exposure. Flash would none do anything for you in this scene - the subject is far too large, although light painting it might have been worth considering (that requires a tripod and a very long exposure (30+ seconds), with you spraying light from a flashlight on the train car from end to end).

[Mike Buckley]

I've honestly never really checked the histogram because I'm not entirely sure how to read it accurately.

That's understandable. However, in my mind, the most important advantage digital photography has over film photography is that we can check the exposure immediately after capturing a scene by reviewing the histogram. I strongly recommend that you make learning how to use the histogram your highest priority of your learning curve. CiC has an excellent tutorial about using the histogram.

[george013]

Yes I'm using manual mode on the camera, but the lens I always have set to Auto.

Your exif tells me you used manual mode, meaning manual exposure. The switch on your lens is for auto/manual focus.

Concerning the amount of focus points, you focus on a plane parallel to the sensor. Always use 1 focus point, so you do know where the camera focuses on. More is not better.

George

[Mike Buckley]

As for the f-stops, I cannot go as low as 2.8 or even 3 because my lens only allows down to 4.

If I followed everything correctly, using f/4 and a shutter speed of 1/30 would have resulted in an ISO value of less than 800, which is hugely different from ISO 12,800 that you used.

[rpcrowe]

I can see several problems in this image, all of which might combine into the reasons that you do not like the image...

1. You have two areas of this image that have diametrically opposed brightness:
The top portion of the image includes the bright sky and is compounded by the bright street light...

The bottom portion of the image includes the dark colored back-lit train which seems to be in deep shadow...

Your camera is trying to find a compromise between these two different areas. As a result the train is severely underexposed.
Note: I am not suggesting that you crop your image like either of the above but, simply want to point out the differences in brightness.
If I were shooting this, I would have stepped closer and tried to fill the frame with the train and exposed for that.

2. The kit lens is not a tool that is great for low light shooting and the T6i may not be the camera for the job either. If I were you, I might think about investing in a faster (lower f/number) lens. The Canon 50mm f/1.8 would give you a three and a half stop advantage over the kit lens and the 40mm pancake lens would give you a three stop advantage. Shooting at f/2.8 instead of f/8 would have allowed you to either use a lower ISO or to gain a better exposure on the train. At a slightly more expensive level, the Tamron 17-50mm f/2.8 lens is a great substitute for the kit lens and is far more versatile.

3. A less expensive way to equip yourself for low light shooting might be to carry your tripod which would allow a far slower shutter speed on a non-moving subject.

4. If your kit lens has image stabilization, by all means turn it on when not tripod mounted. However, there should be no camera shake problem in shooting at 32mm and using 1/160 second shutter speed. I would shoot a number of images at various shutter speeds to test your capability to hold the camera steady at slow shutter speeds' That way, you would know the slowest speeds at which you can shoot hand-held. With IS turned on, I think that I could easily have shot at 1/60 or even 1/30 second exposure and achieved a steady image.
Note: Holding a camera steady when shooting is a learned skill. The camera user manual has some information on this. You "might" be using the LCD as a viewfinder. Holding a camera away from your face to view the LCD is not conducive to a steady camera hold

5. As always, there is a choice in recognizing that the image might have serious problems and deciding whether or not to shoot it. Realizing the limitations of our equipment is a major step in achieving predominately good imagery

6. If you are up close to the train, fill flash (even the pop-up flash might be a small help) could add some brightness to the train.

7. ISO 1280 might be too high to use and expect a very good image. If I were you, I would try to shoot at ISO 640 as my maximum ISO. However, with post production noise reduction, ISO 1,600 was possible even with my old Canon 30D. I did this shot hand held in Hong Kong. ISO 1600, 44mm, f/2.8, 1/45 second, 17-55mm f/2.8 IS lens with IS turned on...



8. Finally, your camera has a very good Auto Exposure Bracketing capability. I suggest that this also might be a way in which you can be a bit more certain to get a usable image...

[Dave Humphries]

Hi again Sergio,

You have a lot to learn, but we'll help and you do recognise that it may have been your techniques (plural) that were likely the cause, so that is a great sign of progress to me made.


However, one other thought ...

The dynamic range, lighting angles and colour temperatures in this scene were never going to result in a great image*, with more experience and knowledge, you'd recognise this and either shoot in better conditions, or do something to take control of the light, but that's a way off yet. If you cannot, due to other constraints, make a difference to the scene (e.g. by shooting at the other end of the day, adding light with strobes, etc.), then perhaps it's better not to shoot, except as a valuable learning exercise.

* Sure, some will argue (and they'd be correct) that something a lot better could be pulled out of a RAW capture, or even several RAW captures (bracketed shots) with buzzwords like HDR, bracketing, monochrome conversion, etc., but the issue remains that I think this scene is not particularly photogenic (at this time of day).


The take-away is that any of us would struggle to capture this scene well, so don't be too hard on yourself, it was one heck of a challenge - but also a very good example for us to diagnose - although that has resulted in (hopefully not an overload) of good advice.

Cheers, Dave

[DanK]

I do a fair amount of night photography, so I will chime in.

First, you wrote that you don't know how to read a histogram. Learning that should be your first step. There are good tutorials on this site. Good exposure is essential in night photography, and understanding the histogram is essential for getting a good exposure under difficulty circumstances like this.

Second, noise: the two things that make noise a problem are high ISO and underexposure, and you have both. Unless something is moving, use a tripod and remote release, set the ISO to 100, and let the shutter stay open as long as needed. With your camera, unless you are in a very hot setting, you should be able to get exposures at least as long as 10 minutes before the sensor overheats. As for exposure: in night photography, you will usually want to expose to the right--that is, get the histogram as far right as you can without clipping. This will maximize the ratio of signal to noise. This will make more sense to you once you have studied the tutorials. You can easily darken it in postprocessing without doing any harm, but lightening an underexposed image will bring out noise.

As Richard pointed out, you have a huge dynamic range--sky that is very bright compared to the foreground. It is likely that you would have to bracket--take two or more photos at different exposures and blend them--or just wait half an hour for the sky to darken.

There is a lot more to night photography, and I can point you to good readings if you would like, but I would start with the tutorials on this site.

[Manfred M]

Sergio - it takes the right tools and techniques to become a good low light photographer.

Low light is a pretty loose term that can include anything from shooting during morning or evening "magic hour" or "golden hour", where you can get away with hand-held techniques, to blue hour, which is the period after sunset when the refracted blue light in the sky still provides enough light to take images (albeit, one generally needs a tripod because the exposures get too long to be able to hand hold the camera). Using artificial ambient light or even the light of the moon is also something that falls into the low light category.

Finally, there are situations where the light is so low that you might have to supplement it with artificial light (i.e. flash or some other relatively intense lights).

Not one single technique covers everything here and in addition to the tutorials here at CiC, there are other sources of information out there - books, online or downloadable videos, etc.

The best thing to do is what you have already done; take pictures, analyze them and incrementally improve on what you are doing.

[Manfred M]

I don't think it's possible to tell at this small image size whether the full-size image is too soft.

I cheated and imported the shot into Photoshop where I lightened it up to verify what I saw in the 100% magnification post at the top of this thread. Parts of the train car are a bit soft.