Moon photography

We've got a full moon at the moment, and I thought I'd take some
photos with my Canon 90-300mm lens and 300D.

But I get double images... does anyone know the trick to it?
One is too dark, the other too bright...

I have uploaded it to my server.
http://numloxx.dyndns.org/~numloxx/moon/

 

Had a look and what you're seeing is the result of internal reflections. I saw
a stunning example of this taken by a student when he photographed the white
lines of a road by headlight .. a nice set of white lines was also recorded in
the sky. the lens in question was a new Sigma EX-PRO 28-70:2.8 .. ugh! Sigma
always had terrible flare and internal reflections due to their element coating,
but I was surprised after all their shrill claims and fantastic reviews that
they still haven't overcome this problem.

New lenses seem to exhibit this far more than the older lenses as lightness of
weight (for AF reasons) takes priority over optical design.

One student borrowed a friends AE-1 while her EOS-3 was in for a service.. when
she got it back she dumped it and bought FD gear and lenses as she'd found far
fewer problems and far better results with the old gear.

go figure..

I can't offer you much of a solution other than to suggest that if you have a
bright light source in the viewfinder then you'd best center it precisely (and
hope the lens elements are collimated well), and I'd also suggest that to
increase image contrast and sharpness for all other shots, for chrissakes use a
_good_ lens hood at all times.. a bellows lens hood if possible (or if you can
afford one)

sorry

Karl

 

That's waaay overexposed. The second dim image is an internal reflection in
the lens.

Use the sunny sixteen rule; the moon is a sunlit image.

ie. 100 iso, 1/125, f/16. Some people recommend f/11. The reflection
should all but disappear once you cut the exposure down, but if it doesn't
you might need to try a different lens.

Chris.

 

Ah great, thanks for the advice. Worked out great.
Now all I need to do is get it to focus properely.

 

You have a camera that you can control manually. This is one of those
subjects where you have both the time and the reason to do so... focus it
manually set the exposure manually, experiment! I'm not saying you
shouldn't ask for advice, but have a read about photography, have a think
about why something is looking way too overexposed it isn't rocket
science hehe

 

Yup, that's it. My 300mm f5.6L does it too with long exposures.

 

Yes, and also by reducing the exposure you'll get a properly shaped moon
rather than a kind of stretched out moon (due to it's movement while the
shutter is open). Also, you'll get more detail in the moon surface (you
can see it a bit in the 'underexposed' internal reflection).

Scott.

 

Don't think it has anything to do with the length of exposure, just the
difference in brightness of subjects... same with flare/aperture star
effects on streetlights at night.

 

Hi Carsten,

Those moon shots are way over exposed. Try 1/250th at f5.6 and bracket
them faster till you get it right. You should see detail on the moon
surface.
One advantage of digital is you can take 50 shots and find the best
exposure.
Use a tripod and cable release, remove any filters like a UV protector that
may be
causing the ghost. BTW the ghost shows detail.

Good luck,
Max...

 

Also set your manual focus to infinity as the
average distance of Moon from Earth is 384,400 km

Max....

 

Hi Karl,

Are you lecturer in photography at a uni somewhere?

Russell

 

Have been, but not these past two years - i'm flat out as the senior photo tech
at perth campus these days .. I've been promised more staff next year so I may
get back into the lecturing .. or mebbe not.. ;-)


k

 

Senior Photo Tech.... very handy around here! Do you mind if we throw you
at Miro every now and again? LOL

 

Nah, is it partially to do with exposure length. The reflection is
always there, not just with bright objects - but the reflection is not
bright so with long exposures you see it and with short exposures you
don't.

Scott.

 

Often, this doesn't give you the sharpest image. I find that the
autofocus or careful manual focus works best.

Scott.

 

This is usually because lenses actually focus beyond infinity to allow for
tolerances in manufacturing and also temperature etc. The markings on the
lens that say infinity are only guides, you still need to look through the
viewfinder.

 

I still maintain it is the difference in brightness, not the exposure
length. Exposure length has absolutely nothing to do with the way light
reflects in the lens. If you were to take a photo of the same scene except
it was far brighter lit (equally across the entire scene), you would get the
same reflections, even if it was only for 1/1000th of a second. I think what
is confusing you is the fact that there is such disparity between the
brightly lit and dark areas in night photography which NEEDS long exposures,
but that doesn't mean that long exposures are the cause - they're just the
result of that sort of photography.

Bear in mind that Carsten's photos were only 1/8th of a second and had that
same effect, hardly a 'long' exposure.

 

Yeah, I completely agree with you. I never said that it was the exposure
length that causes the reflections. What I said last time is that the
reflections ARE there no matter what exposure you use. It's just that
the reflections are much, much less bright than the rest of the image.
Short exposures mean that they dont get exposed properly (well,
actually, you just dont see them). I agree with you that they're more
noticable in these situations with the disparity in brightness. My
'shorter exposure' suggestion was just a way to remedy it. If you do a
shorter exposure, you wont see the reflections. The other reason I
suggested a shorter exposure was because the moon was blown out and
Carsten would get more detail on the face of the moon by a shorter exposure.

No, I never said that long exposures are the cause. Of course they're
not the cause of the reflections, but the long exposures are, in part,
the cause of their visibility.

Well, it doesnt matter how it happens. If you do a shorter exposure, you
will not see the reflections. That's how it happens with my lens.

 

Yup, definitely. Focus to infinity will not produce the sharpest image
(even of the stars in a night sky).

 

For best results, try shooting through a telescope. This one was taken
literally seconds before the start of a partial Lunar eclipse in 2001:

http://www.rudiphoto.net/celestial/full6185.htm

More on my website (URL below).



Regards,

Rudi
http://www.rudiphoto.net/