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Old Jun 26, 2004, 11:17 PM   #11
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I took a quick look at klewis's "spotting scope for F828" thread and realized there was something I had forgotten - being able to focus at a relatively close distance.

For example, I would like to be able to take well-focused pictures of what's in the white rectangle in the pic below (with that taking up the full frame):


Also, on an unrelated note, how do I get my flash to work for a shot like that without alerting my subject? I take more candids than posed shots, it seems. "Hey I look bad! Don't take my picture!" Well if I thought you looked bad why would I be taking your picture?
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Old Jun 27, 2004, 7:31 AM   #12
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Your binocular results are not too bad. So what % zoom was used for each photo?

For your eye question you would probably need a closeup lens or a reversed lens. You might even try the macro setting of the S1 IS.I have collected some info here; http://home.att.net/~galt_57/macro.html

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Old Jun 28, 2004, 3:19 AM   #13
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Pooperdog wrote:
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Your binocular results are not too bad. So what % zoom was used for each photo?
1x for the wideangle, 10x for the optical zoom, 32x for the digital zoom.

I would definitely like much sharper pics at full zoom with the scope. I only have 3,145,728 pixels to work with and (minus any vignetting that may occur - preferably none or near none at full zoom - it's ok if the corners are cut off a little) would like to make good use of them.

btw you can probably tell I was taking a picture of the top of a tree that was some distance away. I can't see the individual leaves, though - I would expect with the portion of the tree taking up that much of the frame I should be able to make out the leaves (maybe not the patterns on the leaf veins though, at least not sharply).

Quote:
For your eye question you would probably need a closeup lens or a reversed lens. You might even try the macro setting of the S1 IS. I have collected some info here; http://home.att.net/~galt_57/macro.html
Would a reversed lens allow me to zoom in and take the shot from farther away? I would like to be able to take those shots without alerting my subject to my presence or my camera's presence.

----------

Also, what about something like a "light gathering lens"? for example it might act like an F/0.25 at wideangle (or if I can't have something that wide maybe an F/0.5 or an F/1.0 (but it would only work properly at wideangle - you'd be back to F/3.1 or F/2.8 at telephoto)
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Old Jun 28, 2004, 2:55 PM   #14
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Realisticallywith vignetting even at full digital zoom your options are limited for digiscoping. I recently posted a list of digiscoping links; you might look through them.

Using areversed lens for macro photography is limited to very close work. If you instead buy a closeup lens such as the Nikon 4T you will have a ten to twelve inch working distance. The macro questions could probably be better addressed in the Lens forum; http://www.stevesforums.com/forums/view_forum.php?id=50
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Old Jul 1, 2004, 2:14 AM   #15
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I took a look at that olympus C-720 one... basically I think I could probably live with the level of vignetting on it... although one thing I'm curious about... why is it that there seems to be MORE vignetting at the mid-zoom-with-scope level than at near-wideangle-with-scope? I would think the vignetting at wideangle with the scope would be quite bad, with it reducing, and in a good-case-scenario, possibly being almost eliminated by the time you got to full zoom.

I can live with vignetting at the corners, but at full zoom or within about 200-380mm or so would prefer to have the top and bottom at least be unobstructed.

Also, I noticed he was using a tripod in what seemed like daylight conditions. Most of my shots with a scope would be handheld. My Canon S1 IS has image stabilization which might help, and I could probably crank down the exposure compensation a stop or two and up the ISO to 100 if necessary, and open the aperture some so I could get a better shutter speed. Do you think a shutter speed of, say, just to throw a figure out there, 1/400" with IS turned on would be sufficient for a handheld fullzoom scope pic, or what would you recommend? with the camera's normal zoom I can get fairly steady handheld shots at around 1/20" to 1/30" if I hold the camera fairly steady.
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Old Jul 1, 2004, 9:27 PM   #16
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I have tried an S1 with a telescope and also with some old add on teleextenders. The IS will not work at the magnification you want if you stay handheld. The problem is the focusing. Without sharp contrasty edges the autofocus does not work. Also the higher power teleextnders like you want have to manually adjusted. To get an idea, use the maximum tele you have and manually foucs every shot and see how well you can handhold it. Also, it takes some steady time for the IS to lock in. With a teleextender over 2.0X, it never does lock in under normal circumstances. The way around this is to set it atinfinity and then take photos from 40 or 50 feet away. Also a teleextender darkens the image reaching the CCD. The effectively turns your f\3.5 to an f8 to f10. You are not going to get the shutter speeds you are expecting. Feel free to buy some teleextenders and try. They will vignette if they are smaller than about 58mm. They 58mm adapter is wider than the lens, but also out in front of it. Any add on lens less than 58mm will vignette at the adapter no matter how the lens is made. You will also very greatly increase the CA even with only a 3mp ccd.

If you really want high magnification at close distances as you indicate, you need an SLR with a 400 (or 100 to 400) IS lens, with a 500D or an some extension tubes. That could be made to take the photos you describe wanting to take. Alas, it is not in the $200 price range.

Good luck in your search,

Demmy
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Old Jul 1, 2004, 9:41 PM   #17
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What I'd really like is a cam that with a fisheye lens has no noticeable distortion, has a low enough aperture to get good focus from 1um (that's micrometer) to infinity, enough resolution for a figure of merit that would blow away a Panasonic DMC-FZ10 with a Crystalvue, low enough image noise to shoot at 1/10000" and get a daylight-lit sky while pointing at a moonless night sky with a noise figure (standard deviation) of <0.1 ... and something that's no bigger than 4x larger than a Digital Rebel.... and for <$800....


I don't think anything like that will ever exist in my lifetime, though...
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Old Jul 2, 2004, 9:14 PM   #18
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Heh, maybe you've been watching too much Star Trek...

I suggest you wait and save up your money...
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Old Jul 6, 2004, 12:58 AM   #19
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Pooperdog wrote:
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Heh, maybe you've been watching too much Star Trek...

I suggest you wait and save up your money...








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Old Jul 6, 2004, 11:59 AM   #20
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I expected the last photo would be of a tombstone...


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