Jump to content

Tom_Kline

Industry
  • Content Count

    1245
  • Joined

  • Last visited

  • Days Won

    29

Everything posted by Tom_Kline

  1. The problem is all the jargon! A list of specifications that are jargon may not be too useful. Nikon does call it matrix but your definition of it may vary and with newer cameras the definition may not be the same as before. The late Jim Church's book has the best explanation of how the thing actually works. BTW I have been using the RS for over a decade now. I use the A mode a lot with the 50mm but go for manual with the 13mm at a small fraction output setting but mostly with the SS200 though I have the SB104 too. Tom
  2. Don, 1.33 times 20 or about 27 inches. This is measured from the film plane. Hope this helps Tom
  3. Hi Eric, The link was working until about the last hour for today me suggesting there might be a 24hour clock. It did keep track of all the postings until the link no longer worked just now. I now get the same error message as above. Tom
  4. The matrix metering aspect of the RS refers to ambient light only, the TTL sensor looks at the center. If there is enough ambient light the strobe output is set to provide a weak fill flash (when the shutter speed dial is set to 'A'), otherwise it switches to TTL and reads the light from the strobe during the exposure. The analogue display indicates which way it is going to go. Tom
  5. Such as when you have the strobe already in your grip! Then it might be easier to adjust distance than switching the strobe setting while you are focusing on a moving fish. For example you could have the aperture set for a 2 foot strobe-subject distance. One would move the strobe back and forth to maintain this distance while, possibly also adjusting for the 'bellows factor' depending on just how close you get (sort of like Kentucky windage), and while tracking and focusing your subject! TTL is a bit more handy for this sort of shooting! Tom
  6. The link I gave may be redundant, sorry. Tom
  7. Hi William, I have a couple of AK fish pix in fishbase. Thanks for the link! No Allen et al. 2003 but there is this: Allen, G.R. and M. Adrim, 2003 Coral reef fishes of Indonesia. Zool. Stud. 42(1):1-72. here is a link to the species: http://www.fishbase.org/Summary/SpeciesSum...esname=henshawi Very useful once you have the name and can search the database. Tom
  8. One could speculate that their aggressive behavior was a result of these mortalities. I gather you and others have dived this site at other times (seasons as well as occasions) when sealions were present but without this behavior. There may be less food available (amount and quality) in winter to making them more stressed (and starved). Tom
  9. Check out this link: http://wetpixel.com/forums/index.php?showtopic=7566 Older UW photobooks go into this in more detail. In-Water Photography by Mertens, 1970; published by Wiley, in particular. It is replete with formulas and graphs. Tom
  10. Marli, Very interesting observations! Were any scientists in your area informed about the corpses? They can perform necropsies, which might explain their deaths. One of the data gaps in understanding sealion population declines is the lack of dead body observations, this is magnified here as well because of the limited number of divers or other observers and general inaccessibility. Tom
  11. Hi Folks, Eels ARE teleost fishes belonging to the order Anguilliformes. Art, Do you have the complete citation? Family name would be good too. I gather it is not a moray (fam. Muraenidae). Thanks Tom
  12. Yes, the 70-200 is VR as well as silent wave! It is also a state of the art lens optically and is priced accordingly. Just a tad heavy unless you intend on using it a bit to justify bringing it on a trip. I use it quite a bit here in AK because of the 2.8 aperture as well as the VR feature. Ambient light levels here can be quite dim! I have owned several versions of the manual focusing 80-200 since they came out in the 70's and often ended up shooting too slow. I used mainly Kodachrome 25 and 64 and they were f/4.5 and later f/4 (never had the 2.8). Between the faster speed of dSLRs (vs. these Kodachromes), f/2.8, and VR, one has quite a number of extra stops in capability today compared to back then! It also depends on where you are going. Going to Komodo, one would probably want to photograph the dragons and would thus want to be prepared optically!! BTW Robert that is a great shot of one!! Tom
  13. There is considerable controversy (esp. here in AK) about what sealions eat and how they are counted (by us). The food: in terms of availability and energy content. Movements: because census data generally depends on counting them hauled out; as well as for food (they may have to travel to feed and their food abundance varies in space and time). The number on a given haul out site can vary. Understanding their movements such as from this study is thus critical. Tom
  14. I found ERDA very accommodating to my photographic needs when I went with them in Oct 04. Specifically I needed an extra tank so I could suck the air out of cameras for the Dive Alert. You need to have local knowledge about where to drop in each day as the conditions in HI can be quite variable. Currents at Molokini going one way one day and the other the next or no current at all. Photo opps can therefore vary quite a bit from day to day at the same site, all were very good, macro through fisheye. They were superb at picking out the best sites and dive plans. I did a number of dives at Reef’s End on Molokini. No two dives were the same. The night dive (they only do one a week) was spectacular with plenty of manta action! You MUST do the ‘Backwall’ several times (see attachment )!
  15. Thanks Kasey for the feedback since I have been considering the 70-180 too. Actually hoping that an AFS version would be released. Since Sigma has come out with the 150 2.8, the 70-180 has been on the back burner. It would be nice to have versatility on a given dive. The 2.8 aperture used for distance > 1m w/o flash or a rather powerful one for the more skittish while also having 1:1 capability. I have read both positive a negative on the 150 AF speed, slow overall but faster than most 105 to 200 macros. I gather the 70-180 is manual focus only - maybe not so good for moving fish?? Tom
  16. Hi Eric, Below is a cut and paste since I had not removed the bookmark from the bookmark sidebar in Netscape (Mac OSX latest version). I got the same error message when I did a similar bookmark save previously. It worked for a few times, then didn't. I even had it set up at one time with two, one new and one old and only the newer one worked (but only for a few hours - maybe it re-sets each day?). I just opened the page and bookmarked the link in your post. It too is titled Search Results. It works right now. It is placed in 'My Sidebar.' It is now set up again with one that does not work and the one I just put which does. If that is not the right one then what is? I hope this info is of value Tom Wetpixel :: Forums > Board Message Sorry, an error occurred. If you are unsure on how to use a feature, or don't know why you got this error message, try looking through the help files for more information. The error returned was: Sorry, but we did not find any matches to display. Try again and broaden your search criteria. If you were searching for new posts since your last visit, it's possible that there are none to show. Useful Links * Forgotten Password Recovery * Register a new account * Our help documentation * Contact the forums administrator Go Back
  17. My understanding is that matrix metering refers to how ambient light is sensed and interpreted by the camera’s algorithms using 1000 some odd light sensors (in more recent cameras) for setting the shutter speed and aperture and not the flash. It was a lot simpler when one had a choice of center-weighted, center-weighted, and center-weighted! A three-decade plus Nikon user and still learning! Tom
  18. I have found the ‘Today’s active topics’ link to be very useful, however, a bookmark of it (which gets titled ‘Search Results’) appears ephemeral. I get it to work for a while (have done a bookmark experiment more than once) but then get a complex error message. Tom
  19. Very impressive! Looks like a useful skill for when DM's start doing pre-dive briefings using powerpoint! But seriously, this could be a useful thing to have for a research project. However, you might have to re-do these on a regular basis (e.g., to look for change). Tom
  20. There is also the old trick from the flash bulb days - move the flash. Varying the strobe to subject distance either by re-arranging your strobe arms (esp. those with a couple of ball joints within their length) or when hand-holding (e.g., using a strobe handle) move the strobe closer or farther away by hand. Recall too that N-V stobes were backwards compatible to N-III. Either have an N-III socket installed (if available?) or block the contacts on the camera shoe connector if needed. Steven Frink shows you how on his Seacam site, it should be similar for Subals. One can also cut the leads. You may want to do iTTL some day and then you will need an N-V socket so you may not want to make too drastic a modification. Tom
  21. A lot of green water here, not to mention silt! Tomjava script:emoticon('')
  22. "9. The CF Card slot in the camera is fantastically designed. The battery compartment cover is not. I will be worried about losing it" You can leave the battery door (hatch) on the battery semi-permanently and buy a separate door for each battery. The battery fits on the charger with the door attached. TK
  23. Thanks Peter for the info on the 70-200 plus 1.7x. I have the 70-200 and was wondering about the 1.7. I have found the VR feature to be very useful. Used it successfully on a heaving ship out in the Gulf of Alaska as well as for hand-holding at low rather slow shutter speeds. The attachment shot was a 1/30th! I am not sure if I would bring it on a scuba trip due to its size and weight . Tom
  24. Looks fragile to me. Image pulling one out or inserting one (esp. in the camera) during a bumpy ride... Tom
×
×
  • Create New...