can't figure it out

[wattsbw2004]

ok i cant figure out why my dslr camera gets little to no detail of the moon at 70mm when my point and shoot gets way better detail with a shorter focal lens.

DSLR is a Sony A700 with 18-70mm 3.5-5.6 kit lens
Point & Shoot is a HP Photosmart R967 with 7.5-22.5mm 2.8-5.0 lens with 3x optical.

Anyone have any ideas as to why this may happen. I know i need a longer lens for my dslr but im still saving up for a good one, until then i guess i have to stick to my P&S camera for better images of the moon.

[Triglav]

When you measure light, make sure you measure it on the moon as this is a very bright object. Don't measure around the moon. Set your camera to iso 100...thst is the theory. Good luck!

[GEli]

P+S cameras have tiny sensors that amplify the listed focal lengths by means of magic. Well, more like light optics, but same idea. Anyways, chances are the long end of your zoom is around 100mm. If you engage the (shudder) digital zoom (I feel dirty even saying it) you can turn that into a "1000mm lense" by having your camera crop your photo for you and then interpolate a bunch of pixels to fill in the holes and keep it from being a big pixelly mess. Long story short, you were using a really long lense on your P+S. My guess is you weren't actually getting much detail, but the interpolation the camera performs fooled you when the photo was viewed in passing/on the LCD of the camera.

So that's the P+S.

For a DSLR, you do not have a tiny sensor. You have a big, beefy sensor. The long end of your zoom would be, with this sensor size taken into account, roughly 105mm (though the magnification is still only equivalent to that of a 70mm lense, but that's a bit advanced for this thread's purpose). Thankfully DSLRs are not innately evil devices and so have no "digital zoom" function built into them, making 105mm the final focal length of your lense.

Problem:

This is not a long enough lense to get any detail of the moon whatsoever. Nowhere near long enough. You can take a shot at around 300mm and, with reams of cropping, get an okay image. At 600mm you'll start to get images of the moon that take up a significant portion of the frame. At 2400mm you can make out individual craters and all sorts of neat stuff, but I'd invest in a few condos or perhaps a beach house before looking into 1200mm lenses.

Solution:

Get a longer lense. I wouldn't do this if your sole interest is getting a good shot of the moon - long, nice glass is expensive - but if shooting the moon really tickles your fancy, you have money spewing forth from all of your orifices or you'll shoot other stuff with this new glass too, go for it. I hope that helped.

[Nicole]

Originally Posted by GEli

...Thankfully DSLRs are not innately evil devices...

Unlike so many of the devices that I own... I mean, just the other day my toaster and microwave wandered into the living room with a kitchen knife and revenge on their minds!

... seriously, I think that some sort of bizarre gas has been pumped into the forums... lots of joking around today Apologies for the threadjack

[FocalFrenzy]

My camera is a Sony DSC-H1 (middle upper-end Point and shoot), with a 12X optical zoom. If I zoom to the upper limit, my images get fuzzy (too far from the sweet spot). Even though it only has 5 mpixels of resolution, it still takes pretty good moon shots, as long as I back down from maximum zoom. It even takes good shots (lots of crater detail), without a tripod. I do get some noise in the sky (not visible on the moon itself), probably due to the camera setting the ISO based on available light, when in shutter priority mode. Altogether, not bad for a 3 1/2 year old camera.
The only advice I can give is to keep practicing with the lens you have, until you can get a longer one. Perhaps you may have better results at less than maximum focal lenth on the lens you have. Try focusing less than infinity, as I've heard that some lenses focus beyond the moon when set to infinity. I hope this helps. I took this one this evening before the storms rolled in.

[inkista]

Originally Posted by wattsbw2004

ok i cant figure out why my dslr camera gets little to no detail of the moon at 70mm when my point and shoot gets way better detail with a shorter focal lens.

DSLR is a Sony A700 with 18-70mm 3.5-5.6 kit lens
Point & Shoot is a HP Photosmart R967 with 7.5-22.5mm 2.8-5.0 lens with 3x optical.

Anyone have any ideas as to why this may happen.

The specs on your HP give "35 to 104 mm" (35mm-film-equivalent) on the focal lengths of its lens. It's because of the crop-factor. Just as your A700 has a 1.5x crop factor, your P&S's even tinier sensor has something closer to a 5x crop factor.

It could also be how you're using the A700. Shutter speed needs to be 1/focal_length or faster if you're handholding. Overexposing to the point of blowing highlights can also lose you detail; using higher iso can lose you detail. And yeah, a much longer lens is really needed.