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Steven Noyes | all galleries >> Galleries >> Images Summer 2004 > Moon : Week 10
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Summer 2004 Steven Noyes

Moon : Week 10

Solar System around Earth

I had been wanting to try this since I got the Mk II. This is a composite to 8 images shot with the 400mm f2.8L IS + 2.0X + 1.4X TCs. Add this to the 1D Mk II's 1.25X FOV crop and the FOV is similar to a 1400mm telephoto on a normal 35mm Camera.

The problem is that the Earth rotates and the Moon goes through the field of view very fast when magnified this much. To counter that, I shot at ISO 3200 so I could keep a rather fast 1/250 second shutter speed while still shooting at f14 to keep the lens at an optimal sharpness. These 8 shots were then pixel mapped in PanoTools and averaged to help cancel out any random noise. I would estimate the noise levels are similar to ISO 640. A substantial gain.

Note that I had originally done 4 images even though I had take 8. I had problems with PT doing optimizations on 8 image and it took awhile to figure out how to get the optimizer to work right (As great as PT is, there are some bugs in the optimizer that makes it go unstable at times)

Canon EOS 1D Mark II ,Canon EF 400mm f/2.8L IS USM
ISO 3200 shot with 4 images stacked to minimize noise. full exif

other sizes: small medium large original auto
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Sheryl 29-Aug-2004 20:41
Hey steven is this one backward

I love it it is a true Steven
Steven Noyes27-Aug-2004 22:05
That little 60mm f11 achromatic refractor does not hold a candle to a Gitzo/Wimberly mounted 400mm f2.8 apochromatic lens. I think I had more fun with that little refractor, however. I know I froze allot more:-)

The digital film does not hurt either. No more Tri-X pushed in Dextrol.

Steven Noyes27-Aug-2004 21:39
Basically, when you take multiple images that you want to average together, it is important that all of the pixels line up on top of each other. The problem is, that unless you are tracking the movement of the object (like the moon), it moves between each shot. Getting a good alignment can then be difficult.

It is possible to use PanoTools to set up lots of control points between the various images and have it then "warp" each image to fit. PT will also take out any lens distortion factors, figure any image rotations and shits and this is most helpful.

To do this, simply treat it as a standard panoramic except every frame is about the same. I use between 10 and 15 control points between each frame. For some reason, sometimes this works great (like this time) and you get pixels alignments to with .2 pixels. Other times, it just falls apart. Still trying to figure out why.

You then generate you pano and siply average each frame together. The end result is that an ISO 3200 shot looks more like an ISO 800 to ISO 1250 shot:-)

Gary Noyes 27-Aug-2004 20:44
I like that you missed the full moon by about 3 days. This makes the texture very visable. It would be interesting to compare it to the similar shot you made about 25 years ago.
Guest 27-Aug-2004 19:54
Do you have any pointers to docs about how you did the pixel mapping in Panotools? That seems like an interesting thing to experiment with.

Also: did you think about opening the aperture a couple of stops so that you could have 1/250th at ISO 800, say? I can see noise in the shot even now, so is the difference in sharpness between f/14 and f/8 greater than the difference in noise between pixel-mapped ISO3200 and pixel-mapped ISO800?

It's a great shot anyway, but I'm curious about how you did it and how you chose the tradeoffs that you did.