Another shot from the long exposure workshop last weekend (more to be found below).
This image was taken with a total of 20 stops ND Filter (two 10 stop filters stacked). The exposure was 45 minutes. Camera was the Canon 1Ds Mark III, noise reduction in camera was turned off.
Image was taken into Camera RAW and then Photoshop for cropping, BW conversion, and tonal corrections (increased contrast). No noise reduction was used, as it was simply not necessary.
The moral of the story? Got money, have no noise...
No seriously, it is impressive to see what digital technologies have accomplished.
Most digital SLR's available today will produce great quality for exposures up to 5 minutes. Above that, noise starts to become a factor.
Realizing that this is a niche technique, this fact will only be interesting to a selective group of photographers. As film doesn't suffer from noise, this would be the alternative to anyone not wanting to commit the $8000 or so for the 1Ds but still wanting to use much longer exposure times.
2 comments:
Hey Marc, have you read anything about the long-exposure performance of some of the other current cameras?
My interest is in Canon's lineup specifically, although I'm sure some would be interested to know about Nikon too. It seems to me that they'd be pushing the technology of all of their sensors along pretty much concurrently, and perhaps some of the other sensors do alright in these situations.
While it's a known fact that the Canon 1Ds MkIII and the venerable 5D are both exceptional performers with low noise at high ISO... that's always been presumably due to the better spacing of the pixel elements on the larger full-frame sensor. Even with the higher megapixel counts on those sensors there's still just more space for each pixel and thus less noise... but is it that same effect that is coming into play with digital noise withing long exposures?
I've suspected that it could be something else, perhaps along the lines of an overall sampling error on the individual pixel data that simply increases over time... but I don't have anything to back this up. I do however have some experimentation to share...
This last weekend I was at a friend's cabin on Keats Island and took these long exposures of the starry night:
http://www.flickr.com/photos/yonderboy/2310649873/in/photostream/
http://www.flickr.com/photos/yonderboy/2310651051/in/photostream/
They were both shot on my EOS 40D with a 10-22mm EF-S lens. No internal noise-reduction. The first one was a 5 minute exposure and the second was a crazy 17.5 minute exposure. I haven't done any modification, colour manipulation, or noise filtering on either of them. They're pretty much RAWs right out of the camera, converted to JPG by Lightroom.
If you click "All Sizes" and then pull up the original-sizes shot on Flick, you can see that while there's some noise, it's actually pretty manageable and you'd need a huge enlarge for it to really spoil the shot.
So, I guess the question I have is... in the exact same situation would a 1Ds MarkIII or a 5D have handled it much better?
Sadly not all of us have the budget to snag a body like that (or the option of borrowing Pooya's behemoth over there). :-/
Frank
So the experiments continue...thanks Frank for posting these shots. I did some test with (Xenija's) 40D as well, and was pretty impressed with the results. I conclude that the image processor in the camera seems to be a very important factor in final image quality. The new Canon's (and Nikon's) have 14 bit processing, and generally show much less noise.
Then, there is the issue of pixel and chip size. It is true that the larger the sensor and each pixel, the higher the image quality. Currently, the largest pixels are actually found in the Canon 1D Mark III (10MP with a 1.3 crop factor chip). The Nikon D3 is even better yet (12MP but full frame chip), and I have one booked for a test run the weekend after next...
Finally, it is said that Cmos chips have lower noise than CCD's. Canon uses cmos chips in most of their cameras, Nikon uses them in the D300 and D3 only.
In almost all cases, noise can also be eliminated using processing in Photoshop or Lightroom software...I also like using a plug-in called noise ninja for Photoshop. A frined of mine uses Neat Image, another plug-in for Photoshop.
I'll share some more info in class this week, and welcome anyone else who wants to join in the testing...in addition to DOF, exposure times can really give that creative kick to your images.
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