Another moon photo

browngo1
Posted 24/11/2007 - 14:36 Link
Took this hand held with a Tamron 70-300 at 300. Cropped heavily and sharpened slightly in Picasa2. What do you think?

Comment Image
Gordon
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K10D
Mongoose
Posted 24/11/2007 - 17:22 Link
I think I am increasingly impressed by the capabilities of the Tamron 300mm zooms. For the price they seem to be very sharp, you have a lot of crater detail there in the lower left hand corner.

300 is really a little short for the moon, so this is about as good as you could expect to get. Very nice.
you don't have to be mad to post here



but it does help
MX veteran
Posted 25/11/2007 - 00:33 Link
Superb.
What exposure and shutter speed
K100D Super, 18-55, 50-200, Sigma 10-20, Sigma 70mm macro and lots of old lenses
mitcho
Posted 25/11/2007 - 08:39 Link
Quote:
Superb.
What exposure and shutter speed
Great detail. Curious about the exposure and shutter as well.
ChrisA
Posted 25/11/2007 - 09:07 Link
Quote:
Curious about the exposure and shutter as well.
It appears to be 1/500s at F8, ISO 560.

There's a free extension for Firefox called "Exif Viewer". Can't recommend it highly enough.

Quote:
300 is really a little short for the moon, so this is about as good as you could expect to get. Very nice.
I'd agree with this. The sharpening has been slightly overdone, I think, since noise is starting to become apparent. Might be able to get it slightly better by setting the camera back to neutral sharpness (this gets recorded in the Exif too) and only sharpening (once) on the computer. Although the moon does move very fast, 1/500s is a bit faster than really necessary, so maybe a lower ISO next time would give you a bit less noise.
browngo1
Posted 26/11/2007 - 09:18 Link
Thanks for all your comments.

Chris, I think I can see what you mean about the over-sharpening. I appreciate your feedback.
Gordon
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K10D
mitcho
Posted 26/11/2007 - 10:05 Link
Quote:
mitcho wrote:
Curious about the exposure and shutter as well.
It appears to be 1/500s at F8, ISO 560.

There's a free extension for Firefox called "Exif Viewer". Can't recommend it highly enough.

Quote:
300 is really a little short for the moon, so this is about as good as you could expect to get. Very nice.
I'd agree with this. The sharpening has been slightly overdone, I think, since noise is starting to become apparent. Might be able to get it slightly better by setting the camera back to neutral sharpness (this gets recorded in the Exif too) and only sharpening (once) on the computer. Although the moon does move very fast, 1/500s is a bit faster than really necessary, so maybe a lower ISO next time would give you a bit less noise.
Just curious! What is your recommendation for a shutter speed for shooting the moon. I have been trying with a slower speed to try and get some framing effects with the foreground (trees etc - the effect is quite good but it just blurs the moon).
ChrisA
Posted 26/11/2007 - 10:25 Link
Quote:
Just curious! What is your recommendation for a shutter speed for shooting the moon. I have been trying with a slower speed to try and get some framing effects with the foreground (trees etc - the effect is quite good but it just blurs the moon).
From the table at the bottom of the article here, the angle of view with a 300mm lens is about 4.6 degrees.

The moon moves at 360/24 = 15 degrees per hour, or 0.25 degrees per minute, so 0.004 degrees per second.

This might not sound much, but if the moon tracks horizontally across the 3872 pixel wide K10D frame, this represents a blur of 16 pixels.

So an exposure shorter than 1/16 will be a blur smaller than 1 pixel.

At 1/60, the blur will be about a quarter of a pixel, which I doubt you'd see.
mitcho
Posted 26/11/2007 - 20:22 Link
Some may shake their heads but that makes sense to me. Thanks. I will do it different next time.
Daniel Bridge
Posted 26/11/2007 - 23:54 Link
Um, think that's not quite right.

If the whole field of view is 4.6 degrees, and the moon travels 0.004 degrees every second, and the width of the sensor is 3872 pixels, then the pixels 'travelled' by the moon would be given by the ratios:

4.6/0.004 = 3872/p

4.6 = (3872*0.004)/p

p = (3872*0.004)/4.6

p = 3.4

So about 1/15s would give a quarter pixel blur, which Chris doubts you'd see.

But the best thing to do is try some out and let us know. This all depends on using a sturdy tripod, and the above calculations are for a 300mm lens, don't forget.

Dan

P.S. If that's wrong, please tell me!
K-3, a macro lens and a DA*300mm...
mitcho
Posted 27/11/2007 - 03:59 Link
Thank you both. I wont argue over the numbers but what I have done in the past was way too slow. I will get up in to that range of shutter speed and have a bit of a muck around.
Mongoose
Posted 27/11/2007 - 08:31 Link
if you have a 2x teleconverter, the moon is bright enough that you could probably get away with 600 F11 with reasonable results.
you don't have to be mad to post here



but it does help
ChrisA
Posted 27/11/2007 - 08:31 Link
Quote:
Um, think that's not quite right.
You're quite right Dan. Again. (It was you that caught me out with sloppy arithmetic over magnification factors IIRC).

I obviously need to go back to primary school.

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