Snapping the
Moon with a Super Zoom Camera
Olympus
SZ-15 with 24x optical zoom
When I got
into astronomy in my early teens one of the first things I wanted to do was
photograph the Moon. Unfortunately it wasn’t so easy in the pre-digital
era and I ended up equipping my own darkroom so I could push the slow ISO black
and white films of the time.
These days
you don’t need a darkroom, but you do still need a telescope and ideally
an interchangeable lens camera and a T-adapter. Or do you?
If you
can’t (or initially don’t want to) spend the £Several Hundred
plus you’d need for a scope, camera and adapter, there is another way.
You (or someone you know) may have a compact camera with a super zoom lens
– loads of families have them kicking around unused between holidays. If
the zoom is ten times or more, you can get interesting snaps of the Moon that
show more than the naked eye. If your zoom is over twenty times, you can get
Moon snaps that are quite surprisingly detailed. Here’s how.
The Olympus
SZ-15
The Olympus
I’m using for this article is an SZ-15 SuperZoom point and shoot camera,
but I don’t want to give the
impression I’m specifically recommending this particular model; I’m
not. In fact, one of the much larger and more expensive super zoom bridge
cameras would doubtless be better (though less likely to be just lying idle
around your home since the last family holiday).
There are a
series of similar Olympus models, from the SZ-10 on, that include a long zoom
lens; the obsolete models can be had pretty cheaply. Other manufacturers make
super zoom compacts as well and some of them may be better than this Olympus. I
chose this Olympus because it is cheap, available and common. I’ll
quickly review its main characteristics, but I don’t want to go into full
details here – there are numerous reports and reviews online.
Design and
Build
In many ways
the Olympus SZ-15 a typical pocket-size point-and-shoot consumer camera: small,
light and simple. It’s larger than a lot of pocket cameras; but
it’s still relatively tiny.
Build
quality appears reasonable, but nothing special. It has just enough brushed
aluminium to prevent it from seeming really plasticky. Aimed at casual users,
it provides a simple set of program modes and it doesn’t even have fully
manual override; it just happens to have an unusually long zoom.
Lens
So what
about that lens, then? The specs say that it goes from 4.5mm to 108mm focal
length. But combined with a very small sensor that gives a claimed
‘equivalent’ image scale to a 25mm – 600mm! When they say
equivalent, though, it’s not clear to what exactly. An APS-C DSLR? A
full-frame DSLR? From my experiments, it would seem they are comparing it to a
35mm camera (i.e. a full-frame DSLR), because the image scale at full zoom is
smaller than a 600mm lens with my APS-C cameras.
Nevertheless, a maximum zoom
equivalent to a 350-400 mm telephoto lens on an APS-C camera is still impressive.
For use on the Moon we should end up with an image scale similar to that from a
small refractor telescope.
Sensor
The SZ-15 has
a 1 / 2.3” sensor – the smallest size generally available (which is
why it’s able to offer such a powerful zoom).
The sensor
has 16 Mp which is a lot to cram into such a tiny area. The result of this is
relatively poor low-light performance. The SZ-15 offers ISOs settings from 100
to 1600, but it generates a lot of noise above ISO 400, despite doing some kind
of automatic dark-frame subtraction.
That doesn’t concern us here because the Moon is bright and we
won’t need high ISOs. Suffice to say that if you were looking for a
point-and-shoot camera to do landscape astrophotography it wouldn’t be
this one. Interestingly, the Sony with a 10x zoom (see Moon photo at end) does
much better for landscape astrophotography than the Olympus, but it’s not
as good for the Moon.
Image Stabilisation
The SZ-15
includes a stabiliser: it’s noisy, but seems effective. You can disable
it if you are using a tripod.
Setup for
Imaging the Moon
Having taken
a brief look at the camera, let’s consider how to set it up to try to get
some images of the Moon.
Mounting on a tripod
To start
with, you really need a tripod. That’s not because you will be using long
exposures – the Moon is bright so you won’t be. From the
point-of-view of shakes you might be able to get away with hand-held photos
using the stabiliser. But there is a problem: the SZ-15 has no manual mode, so
to force it to focus and expose correctly you need to centre the Moon precisely
in the field of view and that means using a tripod. Like most cameras, the
SZ-15 has a ¼-20 thread on the base and you can use just about any
cheap, light-weight photo tripod.
So, you zoom
into the maximum optical zoom of 24x (there are digital zoom setting to twice
that) and snap away at the Moon. What you’ll get will be something like
this:
Clearly this
is no good: the camera isn’t exposing the view correctly, it’s
trying to get an average for all that dark sky and ending up massively
overexposing the Moon. You could try exposure compensation, but even setting
the maximum value of -2 doesn’t improve things much.
Enabling Spot Focus and Metering
If this
camera had manual settings, we’d focus and expose manually, but it
doesn’t. Instead, you have to force the automatic focus and exposure to
adjust for the Moon, not the surrounding sky:
1. Turn the camera on and hit the menu button the back.
2. Scroll down to ‘AF Mode’ and select ‘Spot’
3. Now scroll down to ‘ESP’ and select the icon with a dot in a square instead.
4. Whilst you are at it, find the ‘Compression’ setting in the same scroll-down menu and make sure it’s set to ‘Fine’. This produces the best quality JPEGs (this camera doesn’t produce raw files).
You have now set the camera up to
adjust focus and exposure only for the spot in the centre of the field.
Setting Exposure Mode and ISO
You will
need to select the correct shooting mode and check a couple of other settings.
Turn the
camera on and hit the ‘OK’ button in the centre of the control
wheel on the back.
1. Scroll left and right to select ‘Progam Auto’ and hit OK.
2. Now scroll down and select ‘ISO 100’. This sets the camera to minimum light sensitivity (like we said, the Moon is bright), but maximum picture quality.
3. Scroll down again and select ‘16M’ for maximum picture size.
4. Scroll down yet again and select ‘4:3’ for the picture format.
The camera is now setup as well as it
can be for our Moon shots.
Choosing
your Moon Phase
Non-astronomers
are often surprised to hear that Full Moon is the night a lot of astronomers
shrug their shoulders and stay-in watching the telly: Moonlight blots out
anything other than planets, whilst the Moon itself looks least interesting
when full. It’s the same reason photographers don’t much like
midday on earth – no shadows and a bright sun flatten the landscape and
wash out colour and detail. The effect is the same for us, so that full-Moon is
the least ideal phase to snap. You will get more interesting photos when
shadows are highlighting the topography. Even so, if it’s full Moon,
still get out there and have a go!
In the long
run it might be fun to try capturing as many different lunar phases as you can.
Crescents are arguably the most beautiful, but the thinnest crescents very
early (and late) in the Moon’s monthly cycle are difficult to find
because they are close to the Sun and can be a real challenge to capture with
your camera!
Snapping the
Moon with your Super-Zoom
After all
that setting up, you might think that getting out there and actually snapping
the moon is a formality. Not quite.
The first
thing to do (once you’re setup under the Moon) is to get it precisely
centred in the metering square in the centre of the frame. This is necessary or
the metering won’t expose for the Moon, but for the dark sky around it,
as we saw at the start.
Once
you’ve done that, press the shutter half-way. The camera should now try
to focus and adjust exposure for the Moon. It may take a little while to settle
down, especially in terms of focus, but it will get there in the end! When it
has done it gives a beep and you can snap away.
Make sure
you regularly download and review your efforts. You may find that playing
around with the ISO setting and the exposure compensation can improve your
shots.
If your
images are blurry it might be camera shake. Try incrementally increasing ISO
from 100 to 200 and up to 400 to force the camera to use higher shutter speeds,
until any camera shake has gone. Precisely which setting works best will depend
on the brightness of the Moon (i.e. its phase) and the stability of your
tripod.
If your
photos look washed out, try setting the exposure compensation to under-expose
slightly. Do this by scrolling down through the menus in shooting mode to the
fourth item down: ‘Exposure Comp.’. Try setting this to values
between 0 and -1 (beyond -1 is too much, whilst +ve values will over-expose).
Post
Processing
Once
you’ve got some photos you are happy with, you can improve them further
using processing software. There are numerous free packages to do this and you
only need the basics.
The one
thing to understand about processing is go slowly, apply subtle changes
incrementally.
Sharpness
Sharpening
your photo slightly (but not too much) will likely improve it. Adjust up the
sharpness in tiny steps just until it looks well defined. Too much sharpening
looks very artificial.
Contrast
Again, a bit
of extra contrast will improve most Lunar photos, but too much ends up with a
very artificial look. However, really pushing sharpness and contrast produces a
rather ‘painted’ impression which can be pleasing.
Colour temperature
You may find
that colour of your Moon shots is wrong. Typically they may be a bit yellow
because the camera has chosen the wrong white-balance. Again you can fix this
in post-processing, either directly with white balance (if the package allows
it), or with colour temperature. Experiment until you get the proverbial fifty
shades (well maybe with a bit of buff thrown in)!
Results
Moon taken with
Olympus SZ-15 at full digital zoom
This was the
best image I was able to get, after several sessions. It’s not great
– it’s still a bit blurred, perhaps from lack of perfect focus, or
because optical quality is mediocre. It also has a mild colour cast. It’s
just a cheap camera after all! Still, it’s an interesting photo with the
sort of detail you get through binos and you can make out many of the main
features, including a few prominent craters like Langrenus at top right and
bright Proclus with its rays at the edge of Mare Criseum; you could easily get
an atlas and identify more.
For
comparison, below are (cropped) Moon photos taken with three other zoom cameras
and lenses. As you can see, the best was taken with a Fuji XM-1 and its
50-230mm kit lens. The Fuji is also a compact camera, but one which takes
interchangeable lenses and allows full manual control; it’s a fair bit
more expensive and specialist than the Olympus. Compared with the cheap DSLR
zoom lens and the Sony with a smaller (10x) zoom, the Olympus does well.
From these photos, it seems optical
quality and sensor performance are probably more important than shear
zoominess, so if you have a zoom camera lying around – especially a
bridge camera - you may well be able to do better. Have a go!
Moon taken
with Fuji XM-1 Camera with 5-230mm kit lens
Moon taken
with Nikon D5100 with 50-200mm lens.
Moon taken
with Sony NX camera with 10x zoom