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Everything posted by herbko

  1. I was there this August. The accommodations are excellent, large bungalows, comfortable beds, working ac and internet connection in the room. The food is exceptional, the best I've had at a dive resort. The only issue for non-diver and children is that it's very isolated. The only other thing to do is hang out at the beach and read.
  2. I posted this else where a few days ago. The Canon naming convention for the diopters is very sensible. The part number is the maximum focus distance in millimeters: 500D = 1/2 meter = +2 , 250D = 1/4 meter = +4 ,...
  3. How does the song go? ... can't think of anything I need... Guess I'll just have to spend my money on dive trips.
  4. Hi David, Looks like you're off to a good start. THe sunballs look a little over exposed to me. Are you shooting raw? If so, you can probably get the sunballs to look better with a little WB and exposure adjustments. In general, the secret to a good sunball is to shot at low enough exposure to not over expose the sun and use curves to bring the rest of the image (which may end up underexposed as a consequence) back to the correct exposure. The raw file from ISO 50 is the same as ISO 100 for the same exposure. Setting ISO 50 from 100 only changes the metering and the JPEG conversion.
  5. That's impressive!. I have Comcast cable and they claim up to 6M, but the fastest I've ever seen it is just short of 5M. This afternoon it's down to 2M Too many on this line watching Youtube.
  6. The evidence that I've seen are 1) There are existing Leica and other lenses that do work quite well on Canon FF. 2) Nikon have a even smaller mount and there weren't that many complaints about WA lens vignetting from people shooting the Kodak FF. I have not designed a lens myself and really don't know any more about it than that. Please read what I wrote more carefully. This case does not contradict what I wrote as you seem to think it does. If you are shooting the same subject at the same distance you need half the focal length on the Olympus, so, ignoring the 4/3 vs 3/2 for the moment, 100mm on the FF and 50mm on the Olympus gives the same photo of the same subject at the same distance. If you use the same aperture the Olympus will have greater depth of Field. You need to open up the Olympus 2 stops to get the same DOF. This is essentially what I wrote. Actually for macro the correction is slightly different. That's why I didn't use a macro example. Again. Please read carefully. You have to open the Olympus 2 stops to get the same DOF. Once again. Please read carefully. I wrote same amount of light captured not exposure: 1/4 the exposure on 4x the area (again ignoring the 4/3 vs 3/2). This is important because for a given silicon sensor technology the image quality captured ( signal-to-noise at a given resolution ) essentially just depends on the total captured light. The catch is that resolution on the Olympus will be diffraction limited at 2 stops wider aperture. For a given resolution the FF can achieve any DOF that the Olympus can just at 2 stop higher aperture. Actually the larger sensor is better than that at macro shots. A loss in image quality compared to what is achievable for FF not what is achievable compared to the Olympus. Fundamentally, the limit is the light captured: 4x the area 4x the light for a given exposure. Have a look at the noise test charts on dpreview. You have to move the Olympus noise graphs over two stops to the right to match the Canon 5D, and it's not even matching the resolution. I'll try once again to make it as simple as I can. Assuming I have a Canon lens that is as good as the Olympus counterpart that is 1/2 the focal length and set to 2 stops wider aperture, I can mount that on the 5D and shoot at ISO 400 and get the same field of view and DOF and exposure and capture the same amount of light per photosite if the two sensors has same number of photosites.
  7. There's really not much evidence that the problem is the lens mount. There are examples of excellent results from lenses made by Leica and others mounted on Canon FF cameras. One thing that seems to missed by many in comparing lens performance between different size formats is that you need to scale the F-stop by the length of the sensor in the comparison. For example, to get the same field of view, the same depth of field, and the amount of light to fall on the sensor, of a 20mm lens at F/8 on a FF, you need a 10mm lens at F/4 for the Olympus 4/3 size sensors.
  8. What do you have in mind as legacy features and parts that get into the way? I really can't think of anything that Canon has carried over from the film EOS system that's preventing their DSLR from being better than it currently is. The digital sensor has shown up some problems in some of their wide angle lenses and the smaller acceptance angle of the senor probably has made the vignetting worst in some places. These aren't problems that are cause by features carried over. The system does not prevent Canon from producing better WA lenses than some of their current ones, they just have not done so. There are numerous reports of excellent results from lenses from Leica and others mounted on Canon FF cameras.
  9. There's no need to take notes. The naming convention is very sensible. The product number is the focus range in centimeters: 500D = 1/2 meter = +2 , 250D = 1/4 meter = +4 ....
  10. I recommend getting the 100mm and an 1.4x teleconverter. That'll give you the flexibility of having a 100mm and a 140mm lens. For underwater use, where there's little opportunity to shoot a 150mm lens anywhere close to wide open, there's not a huge advantage to having the extra stop of the Sigma 150mm. At F/8 or smaller, where you'll use it almost all the time, I don't think you'll see much difference in the image quality. The Canon 100mm is great at autofocus and does very well even with an 1.4x. Even if cost is not a consideration, I'd take the extra 1.4x magnification of the 100mm 1.4x combination over the 150mm and it's extra stop.
  11. Beautiful shot! Sorry to hear about your flood.
  12. This is the lens that's on my 5D most of the time. It's a great walk-around lens for a FF. It'll probably make a good fish lens. I've been meaning to try it. It's not supported by Aquatica, but I played around trying to make it work with my old Sigma 105 focus ring. I think it'll zoom with a little duct tape engineering.
  13. Me too. I'd also like to see a smaller macro port, essentially just an extension ring with a piece of glass in front. Let's lobby Blake.
  14. Chris, You're right. There's more detail in the white stripes. I had to bring the saturation way down to see it.
  15. Good question. I'm think it's very likely that there still room for lower exposure in the raw conversion on that that shot. I try hard to not clip any of the channels in the image, but may not have notice clipping that since it's a small area. I'll have another look later
  16. Thanks. This was my first overseas trip with this setup. The EXIF is embedded in all the photos. Look there for the camera settings. In all the WA shots at least one of the two strobes was on full power, usually both. White balance and saturation adjustments in the raw converter makes a big difference. Some of the sunball shots were done in C1, the rest were done in Canon's DPP.
  17. Thanks. No. I always shoot raw.
  18. Thanks for the comments. The two things I wanted to work on during this trip was shooting small swimming fish and sunballs. The conditions weren't always ideal for WA, but I glad to have gotten in few good dives with the WA setup.
  19. Thanks. I have no experience with video and don't know how hard it would have been to shoot those shrimps on whip coral. Wakatobi is mostly walls and those whips were coming out of a wall and there was nothing to hang on to. Also, this is my first trip with this camera and I found that the macro setup is too heavy to shoot one handed, something I plan to fix before the next trip. I took almost all my shots without a hand on anything, and didn't really put their policy to the test much.
  20. I finally got my act together and sorted out my Wakatobi photos. http://herbko.home.comcast.net/wakatobi/
  21. Let's try to get along. UWphotoNewbie has a point that the subject "what 1:1 really means" has been rehashed lots and lots of times on these forums, and so too has the subject of "whether having a smaller higher pixel density sensor is a net win". Perhaps he would like one of these sensors http://www.dpreview.com/news/0611/06110801sharp12mpccd.asp in place of his current one. Think of the tiny subjects that can resolve.
  22. For the sensor size in your camera, a 105mm would only be good for very smaller subjects. If you fit anything bigger than 3 to 4 inches in that frame you'll be too far away to get a really good shot. A 50mm is more versatile, you can use it on a wider range of subjects. Add a teleconverter to it when you want to shoot something very small.
  23. A teleconverter will make the subject bigger at the same distance; this is probably what you're looking for. A diopter will let you focus closer to the subject.
  24. Great show Larry. I really like all those colorful WA shots. I also enjoyed seeing it on full screen instead of the tiny web version.
  25. Matt's right. Higher magnification helps. A larger sensor also helps. Here's one of my first shots after I got the 5D. Just testing the new toy. Shot with the 100mm macro at F/2.8 and ISO 1600. I really like the looks of shallow DOF shots. I'll have to try more of it underwater the next chance I get.
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