Help with long exposure

[bowneracing99]

Hey all, these were taking with an old Xti (i need a serious upgrade) it's Tumon city, Guam. Please let me in on some criticism I never really tried this before.







I have a few more, but these are the unedited... Save for the first which i believe was just sharpened in lightroom 4

[Mr Foreman]

They all look pretty good to me.

[bowneracing99]

It's easier to see when it was larger but there is lot of noise in the first pic. Is my camera capable of taking it out, or is it operator error?

[bowneracing99]

its an xti with a 18-55 lens that it came with...

[Colin Southern]

Great effort

Taking the first one as an example though, I think you have too much that's not contributing anything positive to the image - so - I've given it a quick crop & sharpen for you. Hope you like!

[Stagecoach]

Hi,

I'm not conversant with the noise capability of your camera but what is present in No 1 (which is not particulaty bad) could easily be removed in PP. What No 1 suffers from more I believe is a lack of sharpness at the coastal plane which may be due to you using a low aperture of 5.6 for this one.

As for No 2 and 3 much better with the larger aperture.

In general it is recommended to take night shots such as these before it is completely dark to retain some colour and definition in the sky. If this is your first attempt at night time shots you have done pretty well !

[bowneracing99]

Wow thats a big difference, i appreciate it. Is the noise is to be expected in the sky?

[bowneracing99]

yes these were a first go at at slow exposures. and i was shooting at 4.5 or 5.6 for the first, nd 6 filter, and i believe 11 or so with an nd8 filter for the second 2, you all are very helpful!

[Colin Southern]

Wow thats a big difference, i appreciate it. Is the noise is to be expected in the sky?

Same for the 2nd one - look how it comes alive as a "panorama" with the dead wood cut off and a bit of creative sharpening (click to see full size):



Re: the noise - you'll probably find it's equal portions of technique, camera, and post-processing.

A common mistake with extreme contrast scenes like this is to let the camera choose the exposure in an automatic exposure mode; the camera will generally try to protect the brightest light sources to a significant degree, and thus under-expose the entire scene - which then reveals noise when the levels are adjusted in post processing. A general "rule of thumb" I use is to expose manually for the midtones and just let the highlights blow (they're mostly pin light sources anyway).

Careful post-production helps, but that's a story for another day

[bowneracing99]

wow that changes the composure to look much more thought through, so manual instead of auto, ok.

[dje]

yes these were a first go at at slow exposures. and i was shooting at 4.5 or 5.6 for the first, nd 6 filter, and i believe 11 or so with an nd8 filter for the second 2, you all are very helpful!

Not sure why you'd need nd6 or 8 filters for this. You could achieve the long exposure by

dropping the ISO to 100 (and get less noise)
reducing the aperture (and getting better depth of field).

and then a smaller value of nd filter if necessary (although I'm not sure that this would be necessary).

You could remove the noise in Lightroom in the Sharpening and Noise Reduction screen (not sure of the exact name for this screen, it's called the Detail tab in ACR).

Dave

[Colin Southern]

What ISO were you using?

[bowneracing99]

iso was 100, for the first and 200 for the second i believe, and no matter what, at 30 seconds, it seems to really overexpose without the nd filter, regardless of my aperture... even up at 27... is that user error?

[dje]

According to the EXIF info, 400 for the first image and 200 for the second and third.

Dave

[bowneracing99]

that might be more accurate! I took a string of increasing and decreasing to see the difference, most are deleted....

[Colin Southern]

Normally for night shots you'll want to stick to base ISO, as it gives you the potential for the best signal to noise ratio. If you're using an automatic exposure mode an ND filter normally won't change the exposure at all (in terms of the amount of light hitting the sensor) because although the ND filter will cut down the light reaching the sensor, the camera will increase the time the shutter is open to compensate - so a 6 stop ND filter that gives a 30 second exposure at, say, F8 will give the same exposure without the ND filter at 1/2 second (the effects on motion of the different exposure lengths may well be significant though, so you may well need the ND filters to achieve the desired effects.

On the other hand, if you're in a manual exposure mode (which is what I normally use for night shots) then you'll have to adjust the shutterspeed if not shooting with the ND (compared to shooting with it on).

[bowneracing99]

You all are ridiculously helpful, thank you!