dsjtecserv

Lives in United States Northern, VA, United States
Works as a Technical Director
Joined on Jan 21, 2005

dsjtecserv's recent activity

  • I am surprised that no one has pointed out the obvious: if you were changing the focus on each picture, then of course only one can be in best focus. all of the others must, to varying degrees, be ...
  • OK, you were comparing any viewfinder with live view. What you say is not unique to an EVF but would also be true for an OVF. For what its worth, there is a technique using live view with the ...
  • I'm not clear on how you think that an EVF reduces parallax error. Parallax is the result of the vantage point of the lens not being located in the same position with each shot. Leveling the ...
  • The only "good" position will be one where the lens no parallax point is located over the same point in space as in the other shots. Literally, the "eye" of the lens (the entrance pupil) needs to ...
  • For an astro panorama where everything is at infinity, there is absolutely no need for a panoramic head, as there can be no parallax (unless you are also including terrestrial foreground; please ...
  • Good point. Yes. To the OP: While there are filters such as those I referred to that may have a similar effect as your sunglasses, I emphatically agree with Mark and the others who have pointed out ...
  • I certainly don't discount the use of polarizers in general, nor the warming variety. But not for the situation he was describing, looking in the general direction of the sunset, where the effect ...
  • Well. We aren't talking about simple primary color filters like 8 yellow and 25A red. Rather, his glasses may be similar to the didymium "intensifier" filters used for reducing sodium vapor light ...
  • Regarding suggestions that the effect is caused by your sunglasses being polarized, or that you should try a polarizer to replicate the effect: Polarizers have little to no effect when pointed in ...
  • Actually the situation is not different for live view. The DoF preview button must still be used to view an approximation of depth of field on a live view screen, just as with the viewfinder. ...
  • I could be all wet on this, but some Davis & Sanford tripods had a pneumatic lift. It is possible that part went inside the column that you have, but is now missing. The pneumatic column would ...
  • I think the definitions I posted quite well delineate what is meant by perspective. It is often used (incorrectly) in the vernacular to mean something else, or something less precise. Some people ...
  • Sounds good. No doubt one can find looser or more generalized definitions for "perspective". However when we are trying to speak precisely about what factors and techniques influence photography, ...
  • We agree that the framing and angle of view also influence the overall impression given by a photo. However, they do not influence perspective per se . The definition of the word itself reveals ...
  • No, it doesn't. The size and position relationships are wholly fixed by the viewpoint. This is true even when their are no optics at all (other than your eyes) involved. When you view a scene -- ...
  • The longer the shooting distance, the more the compression. Then you use a long lens to be able to nicely frame those things that are a long way away. Dave
  • To say what Tom said, in a different way: shooting position relative to the subject (in this case, distance) determines perspective (the flattening or compression effect). Focal length determines ...
  • My experience is that most beginners questions are initially answered factually and in a way consistent with both science and photographic practice. Quite often, however, the the direct answer is ...
  • Assuming it is not in Manual exposure mode. If it in Manual mode, the meter will give an indication of what changes in settings are needed to compensate for the ND filter, but you have to make ...
  • Again, I don't recommend trying this with long focal lengths and non-sunset/sunrise suns. The threshold for damage is probably close, and you have seen the examples above where it was demonstrated ...
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