This moon shot was taken with a Canon A710 IS mounted on a tripod with a Canon TC-DC58N 1.75X tele-converter attached, for an effective focal length of 376.5mm. Other settings: Av mode, f/4.8, ISO 80. I’ve found that I must use the auto-focus for sharp images. I also use spot metering to get the exposure correct, as well as the 10-second timer.
I also leave the IS on "Continuous", and just set "Converter" to "TC-DC58N" so that the IS compensates correctly. The IS on Canon compacts doesn't drift so I never worry about it.
I used the CHDK software to get a RAW file from the camera. I then used Raw Therapee to process the image. I used the VNG-4 demosaicing algorithm, and the RL Convolution sharpening method. Thanks to RAW and Raw Therapee, it’s definitely one of the best moon shots I’ve taken with my A710.
http://home.nyc.rr.com/graystar/moon081808-2.jpg
Below is the same image. The moon on the left is the JPEG from the camera. The moon in the center is the unprocessed RAW image. The moon on the right was processed from RAW and sharpened using unsharp mask with an "edges only" modifier. The JPEG has detail but looks very flat and for some reason its detail has a "blob"ish look. The unprocessed RAW shows you just how much processing needs to be done after a capture. The processed RAW has slightly more detail than the JPEG, but more important it has a more 3D quality to it.
http://home.nyc.rr.com/graystar/moons1.jpg
The two RAW processed moons look nearly identical until you zoom them 200%. At that point you can notice the edge-sharpening artifacts in the second RAW processed moon, whereas the first doesn't really show any sharpening artifacts at all.
Moon shot...pushing the limits of a compact
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19th August 2008, 02:38 PMGraystarMoon shot...pushing the limits of a compact
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22nd August 2008, 01:37 PMMcQRe: Moon shot...pushing the limits of a compact
Great moon shot with a compact camera. Some suggestions:
(1) Consider disabling IS. If you are truly using a stable tripod then there is no reason for it. I know you might contend that it does not make it worse, but it certainly won't make it better. I would play it safe and turn IS off...
(2) You mentioned using the spot exposure mode to get an accurate exposure; try doing the opposite. Try to over-expose the moon as much as you can without clipping, then reduce the exposure afterward using (negative) RAW exposure compensation. This will have a huge effect on minimizing noise, which is more of a problem with a compact camera. You should be able to extract quite a bit more detail.
(3) Try disabling auto-focus and instead set the camera to infinity focus using manual focus (not sure how to do this using the A710, but this is pretty straightforward to do with the Canon G-series).
Overall, (2) should give the biggest improvement. Let me know how it works. -
22nd August 2008, 09:16 PMGraystarRe: Moon shot...pushing the limits of a compactThanks!Quote:
Originally Posted by McQ
Unfortunately, I don’t have a stable tripod (Slik Sprint Pro 3Way.) I take these images from inside my apartment. When I turn off the IS I can see slight movement on the LCD. I suspect the problem is the building’s old wood floors. I think my own shifting weight shifts the tripod. As such, I’ve never been able to get as good an image with IS off as I have with IS on.Quote:
Originally Posted by McQ
However, the reason for taking images inside my apartment was so that I can take many images and evaluate them immediately on the computer and make adjustments. But I’ve now figured out what the absolute best settings are, so I really should go outside and place the tripod on concrete and see how that goes.
Exposing to the right...yes, I’ve tried that but the results weren’t as good because the image is already close to clipping. If you examine the unprocessed RAW image you’ll find pixels registering 252 in the red channel. I’ve found that I get clipping even with a +EV of 1/3rd.Quote:
Originally Posted by McQ
It’s done the same way...just press the MF. I’ve tried this many times and the image always comes out blurry. It seems that, like some SLR lenses, the lens in the A710 can be “focused” just slightly beyond infinity. I don’t know why this is. Maybe the extra movement is needed for the shorter focal lengths? I don’t know. All I know for sure is that when zoomed to 210mm, the best focus point for the moon is not the camera’s “infinity” point. Since manual focus is still focus-by-wire and has steps, it just turns out that the camera itself does the best focusing job.Quote:
Originally Posted by McQ
By far and away, the biggest problem is pressing the shutter to focus without moving the camera too much!
I will! Next time the moon comes around I’ll setup on the concrete with IS off. I have a spotting scope and have been contemplating building a digiscope attachment (with a cable release.) Hopefully I can make that happen sometime soon.Quote:
Originally Posted by McQ
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23rd August 2008, 06:57 AMGraystarRe: Moon shot...pushing the limits of a compactThe moon was out so I set up on the concrete sidewalk with the IS turned off and captured some images. There was no doubt that the camera was more stable...the image of the moon in the LCD was rock steady. Unfortunately it didn't seem to help...the results were identical to previous images.Quote:
Originally Posted by Graystar
Hopefully the digiscope setup will do better. -
3rd September 2008, 04:01 AMGraystarRe: Moon shot...pushing the limits of a compactAs a starting point you want to shoot at ISO 64, max zoom, and in aperture priority mode with an aperture setting of f/5. Set your white balance to daylight. Use the self-timer...set it to 10 seconds.Quote:
Originally Posted by Nikoz
I think your camera only has one metering mode, so that's a limitation. I don't think it has manual focus either, so you have to depend on auto-focus.
Metering is your biggest problem. Most likely your first shots will be overexposed. I doubt the histogram will provide any useful guidance...it only shows a few lines at that far left. You’ll have to depend on the LCD, which is generally a really poor indicator of exposure...but it’s all you’ve got at the moment. Read up on exposure compensation in your manual. Set your exposure compensation to –1 and see how the moon looks in the LCD. If it’s just a white dot then try –2. Take a pic and review it. If the moon is still too bright to see any detail then you will need to use manual mode and set the shutter speed yourself.
Try not to disturb the camera when pressing the shutter because the camera needs to focus on the moon.
Good Luck! -
9th September 2008, 02:07 PMGraystarRe: Moon shot...pushing the limits of a compact
It looks good...the moon is centered and exposure looks correct. I think at this point you need to start playing with some of your camera’s other settings. Try different sharpness settings, and also consider adjusting sharpness in an editor such as Raw Therapee or any of the free editors that are out there. Play with bracketing as well.
You should post shots as they come from the camera. Crop them, but don’t enlarge them. It’s more difficult to see what the original detail is like.
Good Luck! -
25th September 2008, 07:01 PMletthbptlRe: Moon shot...pushing the limits of a compact
Where are the pictures?
I tried some moon shots with my nikon p5100 but could not get clear pics. Next time I'll try a tripod with filters. -
16th November 2008, 01:05 PMNikozRe: Moon shot...pushing the limits of a compact
Canon Rebel 1000d,zoom lense 75-300mm...