help on night photography

[pingz]

hi to all.. i was experimenting with night photography with a tripod yesterday.. but i realised that there was a huge amount of noise in my photos, particularly the sky..



i'm using pentax k100D super, 18-55mm kit lens and my set up was f11, 30s shutter speed and iso 200.. the lowest iso i can go is only iso 200..

can any one enlighten me please?

[ameermukmin]

Try cranking down your fstop from f11 to lower. Maybe in the range of F4 or F5, the picture will be better. BTW, you don't need until 30s shutter speed. Probably few secs would be good enough.

When in good light or daylight, using fstop value in the range of f11-f16 will give you good focus.But at night, you need all the light you can get.So go lower on the f-stop number and open up the shutter. This will give a warmer exposure and lesser noise. The picture above is over-exposed and so loss of quality is evident, thus more noise evident in sky.

[lennyl]

Actually, with lower f-stop, the starburst from point light sources won't be as defined. Depends on what TS is after. I'm also curious about what part of the photo you find over-exposed.

My suggestion is to shoot when it is not fully dark. That way you not only have more interesting scene, your shutter won't need to be open for such a long time.

[Mezzotint]

I strongly suggest that you made all yr night fotos in RAW file format, with which you have more control in post-processing. JPEG image quality is not as good becuz the system in yr camera has processed and compressed the image file as "final" output and JPEG files always have artefacts created due to long exposure timing. Alternatively you can use noise reduction plug-in software like Noise Ninja. Hope this helps.

[spheredome]

This is caused by the sky not clear and uniform dark. The sky was illuminated by the surrounding and yet receive insufficient exposure resulted in uneven patches. You will notice dark noise in the water as well. Try to use a black card method, they are mentioned in clubsnap too.

Shoot without lens filter too and use hood if there is light beside you.

[pingz]

Originally Posted by Mezzotint I strongly suggest that you made all yr night fotos in RAW file format, with which you have more control in post-processing. JPEG image quality is not as good becuz the system in yr camera has processed and compressed the image file as "final" output and JPEG files always have artefacts created due to long exposure timing. Alternatively you can use noise reduction plug-in software like Noise Ninja. Hope this helps.

i shot this photo in raw format before converting to jpeg using lightroom but the raw format has the noise as well too..

Originally Posted by spheredome This is caused by the sky not clear and uniform dark. The sky was illuminated by the surrounding and yet receive insufficient exposure resulted in uneven patches. You will notice dark noise in the water as well. Try to use a black card method, they are mentioned in clubsnap too. Shoot without lens filter too and use hood if there is light beside you.

thanks for your advise.. i will research on the black card method

Originally Posted by lennyl Actually, with lower f-stop, the starburst from point light sources won't be as defined. Depends on what TS is after. I'm also curious about what part of the photo you find over-exposed. My suggestion is to shoot when it is not fully dark. That way you not only have more interesting scene, your shutter won't need to be open for such a long time.

yes i realise that the starburst are more defined at f11 onwards.. that was what i was trying out when i used f11 and 30s exposure

[night86mare]

the output here is not noise,

it is JPG COMPRESSION ARTEFACTS, google to find out what it is..

you are saving your pictures with too low a quality.

the k100d super or non-super is very clean at iso200, i used it before and have no complaints

anyhow, the picture is slightly underexposed, exclude the bottom right foreground, and then expose with bulb mode for 1 minute, with cable release, you should get a nicer picture.

[Gengh]

Just curious, is your "noise reduction" function in the custom menu on or off?

I went through some of my night shots done with the K100D, and there's indeed some noise, but not enough to bother me even when viewing on full screen, and probably nothing as bad as what you have. Hard to say for sure since your pic is small and possibly further compressed by CS gallery.

Anyway, I think your test scene is particularly challenging. Loads of dark areas, with several bright lamps and lit areas, and a sky with a strong diffused glow Do you face the same problem with noise in a scene with more lit up areas (but still requiring slow shutter speeds)?

[pingz]

Originally Posted by Gengh Just curious, is your "noise reduction" function in the custom menu on or off? I went through some of my night shots done with the K100D, and there's indeed some noise, but not enough to bother me even when viewing on full screen, and probably nothing as bad as what you have. Hard to say for sure since your pic is small and possibly further compressed by CS gallery. Anyway, I think your test scene is particularly challenging. Loads of dark areas, with several bright lamps and lit areas, and a sky with a strong diffused glow Do you face the same problem with noise in a scene with more lit up areas (but still requiring slow shutter speeds)?

the nr function was on i haven't really tried with a more lit up area. i will try it again and see if there's a difference

Originally Posted by night86mare the output here is not noise, it is JPG COMPRESSION ARTEFACTS, google to find out what it is.. you are saving your pictures with too low a quality. the k100d super or non-super is very clean at iso200, i used it before and have no complaints anyhow, the picture is slightly underexposed, exclude the bottom right foreground, and then expose with bulb mode for 1 minute, with cable release, you should get a nicer picture.

thanks for your advice.. but i shot in in raw format and the black dots are already there.. but probably i will reattempt using the bulb mode as what you suggested

[Gengh]

Originally Posted by pingz the nr function was on i haven't really tried with a more lit up area. i will try it again and see if there's a difference

Just to show you what I mean... this is one of my night shots from the K100D that I consider as having "average" amount of noise.



And a 100% crop looks like this:


This shot was taken with ISO 200, f/10, 13s exposure. I don't have any with 30s exposure for a more direct comparison.

[calebk]

Originally Posted by ameermukmin Try cranking down your fstop from f11 to lower. Maybe in the range of F4 or F5, the picture will be better. BTW, you don't need until 30s shutter speed. Probably few secs would be good enough. When in good light or daylight, using fstop value in the range of f11-f16 will give you good focus.But at night, you need all the light you can get.So go lower on the f-stop number and open up the shutter. This will give a warmer exposure and lesser noise. The picture above is over-exposed and so loss of quality is evident, thus more noise evident in sky.

I don't know what you're writing, but it definitely contradicts itself and is very misleading.

1) Stopping down the aperture does not give you good focus
Stopping down gives you added depth of field, not to be confused with sharpness or focus.

2) If you're on a tripod at night, a longer exposure generally has no detrimental impact on a photo
In fact, a longer exposure would let in more light, and you can use that to whatever effect you wish. Night photography is done on a tripod for a reason - so that exposure time does not become a hindrance to you. There is no need to open up the aperture to get more light, especially if you want the depth of field.

3) Opening up the aperture or increasing exposure time does not give you a warmer exposure
Self-explanatory. It gives you a higher exposure value.

4) When a picture is overexposed, it does not result in loss of quality per se
This loss in quality seen here is due to JPEG compression. Overexposed images result in loss of detail if the details are blown out of the exposure latitude/range of the camera sensor.

5) When a picture is overexposed, noise does not become more evident.
On the contrary. It is when an image is underexposed that noise becomes more evident.

[lenrek]

Originally Posted by calebk I don't know what you're writing, but it definitely contradicts itself and is very misleading. 1) Stopping down the aperture does not give you good focus Stopping down gives you added depth of field, not to be confused with sharpness or focus. 2) If you're on a tripod at night, a longer exposure generally has no detrimental impact on a photo In fact, a longer exposure would let in more light, and you can use that to whatever effect you wish. Night photography is done on a tripod for a reason - so that exposure time does not become a hindrance to you. There is no need to open up the aperture to get more light, especially if you want the depth of field. 3) Opening up the aperture or increasing exposure time does not give you a warmer exposure Self-explanatory. It gives you a higher exposure value. 4) When a picture is overexposed, it does not result in loss of quality per se This loss in quality seen here is due to JPEG compression. Overexposed images result in loss of detail if the details are blown out of the exposure latitude/range of the camera sensor. 5) When a picture is overexposed, noise does not become more evident. On the contrary. It is when an image is underexposed that noise becomes more evident.

Yes... This is what I came to understand as well.

Anyway, to TS, have to check the Tips, Tricks and Guidelines for Night Photography?

[ameermukmin]

Originally Posted by calebk I don't know what you're writing, but it definitely contradicts itself and is very misleading. 1) Stopping down the aperture does not give you good focus Stopping down gives you added depth of field, not to be confused with sharpness or focus. 2) If you're on a tripod at night, a longer exposure generally has no detrimental impact on a photo In fact, a longer exposure would let in more light, and you can use that to whatever effect you wish. Night photography is done on a tripod for a reason - so that exposure time does not become a hindrance to you. There is no need to open up the aperture to get more light, especially if you want the depth of field. 3) Opening up the aperture or increasing exposure time does not give you a warmer exposure Self-explanatory. It gives you a higher exposure value. 4) When a picture is overexposed, it does not result in loss of quality per se This loss in quality seen here is due to JPEG compression. Overexposed images result in loss of detail if the details are blown out of the exposure latitude/range of the camera sensor. 5) When a picture is overexposed, noise does not become more evident. On the contrary. It is when an image is underexposed that noise becomes more evident.

Well my technical wordings are not corect, yes i agree. But what i mean is exactly what has been explained by others and yourself. Thanks for pointing out my poor technical wordings.
I did mean more depth of field for point 1.
as for point two. Help me out here. When i use lower F value, maybe f4 or F5, i can still get a starburst effect as long as my exposure is above 2secs that's my point. But what you mean is if you use F11 or higher, you get more defined yes?
And i agree fully with point 4 and 5. Thanks for pointing them out. BTW, you have good way of phrasing yourself when it comes to technical explanation.

[ameermukmin]

Originally Posted by Gengh Just to show you what I mean... this is one of my night shots from the K100D that I consider as having "average" amount of noise. And a 100% crop looks like this: This shot was taken with ISO 200, f/10, 13s exposure. I don't have any with 30s exposure for a more direct comparison.

fantastic shot!!!

[lennyl]

Originally Posted by ameermukmin as for point two. Help me out here. When i use lower F value, maybe f4 or F5, i can still get a starburst effect as long as my exposure is above 2secs that's my point. But what you mean is if you use F11 or higher, you get more defined yes?

Yes.

I tried to search google for an example, but came up empty (did not try very hard though). The next time you do a tripod mounted night shoot, focus, switch to MF, then take 5 shots with aperture values varying 1 stop between the different shots with equivalent metering. The difference is fairly obvious.

[ameermukmin]

Good suggestion. One good experiment to try next night shoot. Thanks guys. I learnt alot from this thread alone. Hope pingz did too. Thanks

[pingz]

thanks to all who have advised.. i have learnt a lot too.. i will try out again

[sachinohms]

you can trying using rule of 8..

F8 and 8 seconds exposure for night photos.. it generally works very well for me...

Regards,
Sachin