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yoshio

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    Shift Adapters

    in Olympus

    Posted

    <p>Harold, would you agree then that it is of diminishing significance as the focal length increases?</p>

    <p>Zach, do you have any evidence to support that? Have you done much shifting? Personally I have used TS-E24mm lens and LargeFormat with 90mm (where shifting is more common) for some years and can say I see little advantage to shifting. Please note I provided some substance to support my argument, you provided nothing other than negation of the assertion.</p>

    Shift Adapters

    in Olympus

    Posted

    <p>if you want to do this with a shift adaptor by all means. The primary benefit of a shift adaptor in in the use of wide angle lenses. Shifting of normal lenses offers less advantage. So if you are intending to use a 12mm or shorter focal length lens you will gain something.</p>

    <p>I have seen no evidence that shifting results in significantly better image products than does perspective correction in any number of good software systems. When you shift a lens you move to that portion of the lens which has less resolution, so while you don't "loose pixels" you do loose resolution. I believe if you look at the MTF charts of many lenses they fall off significantly past the center. An example of this can be found <strong><a href="http://www.photozone.de/canon_eos_ff/541-canon14f28mk2ff?start=1">here</a></strong>. You can observe that resolution falls off from 3620 to 2937 as you move to the edges.<br>

    <img src="http://www.photozone.de/images/8Reviews/lenses/canon_14_28_ff/mtf.png" alt="" width="514" height="388" /></p>

    <p>So you can choose if you want 6 eggs or 1/2 a dozen eggs.</p>

    <p>if you are concerned then I suggest you consider applyinng basic panorama technique and stitching THEN perspective correcting. I'm sure you'll find better results that way.</p>

    panasonic lumix gf1. How is standing up?

    in Olympus

    Posted

    <p>Perry</p>

    <p>speaking as one who still uses (less than I would like) my 4x5, 35mm and has used G1 since 2009 I can say you will be quite pleased. Certainly the G series cameras have not changed much in sensor performance from the first series, although the GH2 reportedly does a better job of video than the GH1 when hacked.<br>

    Myself I'm very pleased with the video of the G series.<br>

    Viewfinder, that is what stops me from switching from GH1 to GF1, I so much prefer the viewfinder of the G1 GH1 that the add on viewfinder is not enough for my preference. The amount of dots in the finder is one part, but that the dots each cycle through R G and B makes them seem much better than the others which have similar or higher dot counts but count R G and B as 3 dots.</p>

    <p>Personally I don't like going over 800ISO but I often get to use a stop or two faster lens anyway so it evens out. For instance I often bring a 100mm (effective 200mm) f2.8 lens.</p>

    <p>Shooting and assembling in PS is inferior to assembling with a tool like PTGUI or Hugin (which is free) and will take any distortions into account.</p>

    <p><img src="http://farm7.static.flickr.com/6160/6153929197_24a686967e.jpg" alt="riverPano" width="500" height="259" /><br>

    this is 4 portrait orientations stitched with PTGUI<br>

    my string has been cut into individual stringettes (just the right size ... for a million and one household uses ... as used in hospitals)</p>

    <p>I would venture that a G1 may be a better camera as once you try and get familiar with the pivot screen you'll be hooked IMHO. The size of camera is not so different.</p>

    <p>Essentially I feel that the only thing you miss going from a 5D (or did you mean Mk2) will be shallow DoF in mid distance for normal lenses and perhaps some of the same in wides (I happen to be quite fond of my 21mm on full frame)<br>

    For everything normal to telephoto you'll find the move to micro 4/3 is mainly in your favour.<br>

    You would not know, but its worth mentioning that when you start using the "zoom focus" confirmation you'll soon see that you are getting more accurate results with critical focus when using lenses wide open. Compared to the vagaries of "near enough" AF on SLR (and issues with focus screen positioning) you may seen find that you don't like the lack of control that comes with a SLR. For me having the G1 is like having a magnifier finder on the eyepiece that goes away in an instant for me to see the overview.</p>

    <p>good luck</p>

    What are optimal scanner settings?

    in The Digital Darkroom: Process, Technique & Printing

    Posted

    <p>Hello</p>

     

    <ul>

    <li>Is it possible to influence the analog CCD signal before it is being sampled and digitized, with the controls in the scanner driver? I think this is not possible and that therefore I can’t use the controls to</li>

    </ul>

    <p>in flatbed scanners not that I know of or have ever found evidence to support directly, but I do have anecdotal evidence that changing some settings in Epson scanners makes scan times longer ... see <strong><a href="http://cjeastwd.blogspot.com/2008/10/epson-3200-more-optimal-scans.html">this</a> </strong>reference</p>

     

    <ul>

    <li>improve the scan results with the scanner driver settings. So it is better to use a good photo editing software program to restore as much as possible of the photo.</li>

    </ul>

    <p>definately, and it can reduce time taken in post processing (<strong><a href="http://cjeastwd.blogspot.com/2009/10/quick-negative-scan-tutorial.html">reference</a></strong>)</p>

    <ul>

    <li>What are the best scanner settings to get as close as possible to the RAW image of the CCD image of the scanner. For example: should I use linear gamma or the standard gamma 2.2?</li>

    </ul>

    <p>see above reference</p>

     

    <ul>

    <li>What is the maximum size of the color space of a photo? Does it fit inside the color space of the scanner and does it make any difference which color space I use?</li>

    </ul>

    <p>uncertain, but will vary on type of film. I belive that going to big a colourspace will introduce noise by posterisation</p>

     

    <ul>

    <li>Does it make sense to use 48 bit scans or are the lower 8 bits only representing signal noise? Is it sensible to scan at the lowest needed resolution to reduce the noise in the CCD signal? Especially with<br />dark black and white photo’s with little contrast in the dark area’s?</li>

    </ul>

    <p>very much so, but mainly because you are unable to tune the analog gain to fit within the circuit and the filmtype. I belive most scanners are designed with the range of E6 films in mind, Neg often results in greater stresses on the systems as Blue channel often has a small range. I do not believe that CCD noise is in any way influenced by scan density. Software will make a better fist of noise reduction if you scan at higher resolution - denoise - reduce<br>

    ^,^</p>

    interval taking camera with special requirements

    in Mirrorless Digital Cameras

    Posted

    <p>Hello</p>

    <p>I'm seeking a camera to use in a monitoring project where we do not have access to power but require the camera to take images every 5 minuets. I would guess that an intervalometer attached to a compact camera would do the trick, but we would like to have it operate autonomosly for some time. This would mean it would need to</p>

    <ul>

    <li>accept DC in; </li>

    <li>power up on intervalometer timer or run 100% of the time</li>

    <li>have a manual focus or be able to not refocus or re zoom when ever it felt like it</li>

    <li>be reliable</li>

    </ul>

    <p>the camera would be in a case on a pole. We were examining the EyeFi cards for transfer of images to a computer</p>

    <p>If there is an existing product which someone knows that fits this bill, it will save me rigging up something</p>

    <p>thanks</p>

    Panasonic 100-300mm low light vs similar lenses

    in Olympus

    Posted

    <p>Andrew<br /> I would also advise that there is F-Stop and then there is tranmission. F-Stop is only a reflection of the diameter of the hole, transmission mean how much light actually gets through to the sensor. I have found many zooms which are f5.6 transmit as much light as other lenses do at f8. This has a direct impact on the shutter and ISO setting required to get the exposure required (of course)</p>

    <p>I use a Canon FD 300 lens on my G1 and it works fantastically. I also use a monopod as this makes panning easy while keeping flexibility<br /> <img src="http://farm4.static.flickr.com/3543/3420064503_6c12f58773.jpg" alt="" /><br /> This lens is of course manual focus so you will need to learn that technique, but you will find (particularly at those distances) its quite easy.<br /> The lens costs less than US$200 and I'm guessing you're not going to be using the 100 end of your zoom looking at those pictures. Here is a shot taken with that lens at a polo match<br>

    <img src="http://farm4.static.flickr.com/3297/5755950385_7b306f2aaa_z.jpg" alt="polo" width="640" height="480" /><br>

    see how you go</p>

    m4/3rds and shooting action sports

    in Olympus

    Posted

    <p>I wonder why everyone has lost the ability to focus a camera? Personally I get as many hits and misses out of AF on my EOS as I do out of my GH1 and my FD lenses. It does take a little practice. Particularly when you add in the back focus issues that still effect cameras</p>

    <p>Still, I do prefer the 5 frames per sec for sports, makes a nicer 'double tap' than on the GH1</p>

    Four-thirds lens with micro-four-thirds

    in Olympus

    Posted

    <p>Hi<br>

    speaking as a G1 / GH1 owner:</p>

    <blockquote>

    <p><strong><em>just continue to use my old E510 with the 25 pancake as a carry-around. :-)</em></strong></p>

    </blockquote>

    <p>its something I consider buying for just that reason ... that 25 pancake (although I would probably get the 410)</p>

    Canon 70-200 f4 or Zuiko 50-200 SWD for Panasonic GH2

    in Olympus

    Posted

    <p>Panasonic G cameras have many strengths, such as lightness, ability to use a variety of good optics (I use the FD Canon ones) but when it comes to fast AF and working in the realm of such competent work horses as the 70-200 I think you already see the logic of the Canon EOS system. While I love the snap to focus I in reality seldom need it, and instead have found that for my uses the precision of focus afforded by the EVF and magnification gets me more keepers than the front and back focus issues I was having with my 20D</p>

    <p>YMMV of course ;-)</p>

    Panasonic G3 announced!

    in Olympus

    Posted

    <p>Akira</p>

    <blockquote>

    <p><em>The majority of people still judge the image quality by the pixel count, so 16MP sensor would be regarded as the way to go.</em></p>

    </blockquote>

    <p>someone at work suggested to me that their phone had more megapixels than my Canon 10D (implying it therefor took eaual quality images so why would I bother with all that paraphernalia).</p>

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