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ChrisRoss

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ChrisRoss last won the day on March 28 2020

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About ChrisRoss

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    http://www.aus-natural.com

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    Male
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    Sydney Australia

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    Australia
  • Camera Model & Brand
    Olympus OM-D E-M1 MkII
  • Camera Housing
    Nauticam
  • Strobe/Lighting Model & Brand
    INON Z-240

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  1. No problem, don't forget the 230mm dome is a big piece of gear! you need to actually see one to appreciate it. Also by the time you buy the 230mm dome, 70mm ring and an RF15-35 that comes to just over $AUD 7,000 and the WACP would only be a few hundred $ more based on new prices ex Nauticam distributor and digi direct for the 15-35 in Australia and the optical quality will no doubt be better in the WACP. The 28-80 lenses are very cheap ex Ebay. Also don't discount the need for a focus gear for the Samyang - you really can't set it for hyperfocal distance due to the dome port optics.
  2. The problem with 14mm lenses is you really starting to push the limits with the corners of the frame even with a 230mm dome, people complain about corners with their 16-35 zoom lenses and it gets to be more of a problem the wider you go. The other problem is that good performance on land does not always translate to good performance behind a dome and there does not seem to be good guidance on how to tell without trying the lens. Some examples are the excellent (on land ) Nikon 14-24 and Canon 11-24 which are said to be somewhat disappointing underwater - the Canon perhaps more due to the attempt to get good corners in a reasonable size dome. I would also note that you don't need a huge dome for fisheyes- the recommended Nauticam dome for 15mm full frame fisheyes is the 140mm glass dome. You certainly would be looking at a big dome with a 10-24 lens assuming it was rectilnear. As far as housing the 14mm Samyang the 14mm Canon lens would give a good starting point, being the same length (94 vs 96mm) . Most ultra wide (weitwinkel) lenses have the entrance pupil right towards the front of the lens, so it is likely to need close to the same amount of extension. You would also need to sort out your own focus gear as no one supports the lens that I am aware of - as an aside there is usually a reason support is not provided.
  3. Generally best to use the port charts, there is a separate one for the WWL-1: https://drive.google.com/file/d/16jbJ08JAzMxCLoI6LfraDJzks75oWC5e/view You'll see the recommended port for use with 28-60 on N100 housings listed there.
  4. How large do you want to print? With proper treatment you don't really need that many MP - 20 MP prints natively at 44 x 33cm at 300 dpi and you can go as low as 150 dpi with proper treatment of the right image. By proper treatment I mean good processing and profiling of a good clean shot, probably at min ISO and printed on a top end inkjet by a fine art printing service. See this link for some details: https://www.duford.com/2016/04/megapixels-vs-print-sizes/ Don't try this with big chain bulk printing outfits. It will no doubt be easier and you'll have cropping space as well if you are selling a lot of truly big prints to be using a larger sensor camera of course. It sounds like given your interest in pelagics it's a choice between a 16-35 class lens the or a WACP with a 28-70 or 28-80 lens. All the specs talk in terms of diagonal field of view and due to the barrel distortion of the WACP it stretches more in the corners than horizontally so I prefer to look at the horizontal field of view to compare Wet optics of this type with rectilinears for reach. You generally frame such subjects roughly across the frame not along the diagonal. In general I'd suggest looking at the 16-35 f4 - the 2.8 lens brings little benefit UW where you are stopping down for the corners as a rule. So a 16-35 will give 96-54° across the horizontal frame a 28-70 in WACP about 122-75° or 122-68° for a 28-80 lens. Which shows the 16-35 will have a little more reach, in rectilinear terms the 28-80 becomes 10-28 lens when looking at the horizontal field of view. The 16-35 used for pelagics, you could relax the criteria a little as sharp corners are not so important, so shoot a little wider aperture or even perhaps try out a smaller dome, though it could be a costly experiment, I'm not sure I'd chance using the 180mm dome even though it is listed as an option.
  5. A 20 MP m43 image will print natively to 44 x 33cm at 300 dpi. There is a school of thought that when printing large 150 dpi is enough and that gets you to 88 x 66 cm which is around A1 size. Retina displays are 220 ppi which is regarded as the limit for human eye resolution for Ipad viewing distances. Big prints are generally viewed from further back than this and you would have to examine the print up close to pick the differences. This of course is based on a well exposed and processed photo taken in nice conditions with a "good" lens and printed using good technique on a quality printer with files properly prepared and being profiled for use with a nice inkjet paper. There is also the new Adobe super resolution option. It may not work so well for budget level prints from big chains.
  6. Agree with Tim, full frame has an advantage, but it's smaller than the advantage on land and the costs can be big depending on what lenses you want to use. Big domes, expensive lenses harder to travel with. If you've got deep pockets and are prepared for the travel difficulties sure it produces nice results. For example if you use a 7-14 lens on m43, you probably have a 180mm dome, the equivalent in full frame is 16-35 and needs a 230mm dome, it's not quite as wide and the corners are not as good, so this brings in the WACP which produces amazing results, but is big heavy and expensive. For fisheye, dome sizes are similar of course however on m43 you can adapt a Canon 8-15 to get a truly versatile fisheye zoom that really you can't re-produce in larger formats. The question to ask is what specific problem are you trying to solve with full frame?
  7. in underwater terms, 24mm is not that wide, UW you don't put on a wide lens to get a bigger angle of view , you use WA to get closer to your subjects so you have less water between you and your subjects. You are also placing the lens behind a dome and this means the lens needs to have good close focus capability. Dome ports are a problem with wide angle work and the required size of the dome port scales with sensor size. the classic wide angle lens for UW work is the 16-35 and in full frame this needs a 230mm dome to get decent corner performance. As I said the 24mm is not that wide in UW terms so you can get away with a smaller dome. You also need to stop down to f11-16 to get the corners sharp with such a lens at the widest setting. All this applies to rectilinear lenses, fisheyes can use smaller domes and they are to goto choice for close focus wide angle work and reef scenics and a 15mm full frame fisheye works well in the Nauticam 140mm dome. One of the disadvantages of SONY is lack of full frame fisheye and you need to adapt a lens like the Canon 8-15 or Sigma 15mm fisheye. You choice will depend a lot of the type of shots you prefer, rectilinear lenses are good for wrecks as they keep straight lines straight and also for things like sharks where you may not get close enough with a full frame fisheye. For shots with people in frame the rectilinear may also be preferred, if you place a diver too far from centre the shape distorts with a fisheye - this is not normally a problem for reefs and other UW subjects. Wet lenses are a little in between Fisheyes and rectilinear and were developed specifically to deal with the problems of using large domes but still getting corner problems. The 230mm dome is really quite big and hard to travel with. The wet lenses are sharp across the frame and work well at wider apertures. They are are not quite rectilinear and have some barrel distortion, but nowhere near what you get with a fisheye lens. I would also suggest that housing a land camera you already own is not always the best choice. Other systems may do a better job UW. Smaller format sensors are always cheaper to house and can be more versatile UW. The advantages of full frame are somewhat reduced underwater in my view. I'm not saying don't do, but go in with your eyes wide open and decide if you want to spend the extra $$ or not, the savings can be significant. In may case I could buy the housing , camera and one port for the price of just the housing for my land camera.
  8. Could be that code is still in there, just not documented - to do TTL in live view it needs to drop the mirror pre flash and raise it again, so maybe if it detects a strobe there it deactivates it. As an experiment you could tape over the smaller connectors on your camera hot shoe, leaving only the centre one exposed - that way it can only trigger - many cameras will complete the circuit in sync which will trigger a manual strobe regardless when the shutter is released to enable them to work with manual only strobes. If your hotshoe has 5 pins it may be enough to tell the camera a strobe is there but because it can't work out how to deal with it it decides to de-activate flash.
  9. What are the details for your triggering. I am assuming you are using wired triggering and that it's manual only. Do you have any sort of TTL board as well? Typically it is necessary to check the full setup you are using from hotshoe all the way through to the strobe. I would think the issue is likely to lie in the camera as in general unless you have some sort of TTL board in the mix the camera does not know there is a strobe attached and simply closes a circuit, though I believe the strobe is supposed to work with old Nikonos style TTL-Auto (not e-TTL as used with modern digital cameras). Doing some googling turned up this post, apparently Canon DSLR's won't trigger the flash in silent mode and live view with non Canon strobes: https://www.dpreview.com/forums/thread/2949614 I know the system worked previously with the DS-51 - perhaps it locked out the Canon system somehow. Are you using the same hot shoe connector with the new strobes? If it is changed - how many contacts are on the connector, comapred to the old? I am guessing the camera will probably still trigger a manual strobe in live view but may block it if there are other connections made through other pins.
  10. It's a wide open question and really depends on what you want to shoot. Unfortunately full frame imaging carries baggage in that you need big ports for rectilinears and you usually find yourself stopping down more for depth of field. A few points: the Canon 8-15 is effectively a dual lens on full frame either it's an 8mm circular fisheye or 15mm full frame fisheye - in between you get odd vignetting. For circular fisheye you of course need to pull off the dome shade. For rectilinear the go to lens has been the 16-35 f4 (the f2.8 has no real advantage UW) which needs the EF-RF adapter- though Canon have released an RF 15-35 f2.8 now which is quite a pricey lens. To use this a 230mm dome is generally recommended - this is a truly big item and hard to travel with. You are stopping down to f11-16 to get good corners and some people add the S&S correction lens to get better corners without stopping down so much. As you said the alternate solution to the above has been a WACP for APS-C and full frame cameras which is big heavy and expensive but gets excellent corners at much wider apertures and truly excellent optical quality. Albeit with some barrel distortion - the lens is not rectilinear but is close. The WWL is cheaper and easier to deal with but so far only a couple of Sony cameras have suitable lenses in full frame. The WACP or rectilinear in a big dome is a big investment - which is why I suggested thinking about what you want to shoot with it - traditionally this has been bigger animals in blue water where they don't come quite close enough for the 15mm fisheye or things like wrecks where you want to keep straight lines straight. For Reef work you can normally get closer with the fisheye unless you are doing smaller fish portraits. Compare this to m43 where you could continue to use your WWL with a more stills oriented camera or could adapt the 8-15 to get a true fisheye zoom which goes from a 180° diagonal fisheye to the equivalent to a 28mm lens on full frame on the horizontal axis of the frame . If you wanted rectiilinear you would be using a 180mm dome with the 7-14 lenses on offer. All much cheaper and easier to travel with then the full frame options.
  11. Have you talked to Pete Lightowler?, he does a lot with Gates and Red cameras, he does a bunch of workshops and other stuff and dives with the gear.
  12. It's worth a try, cost is next to nothing, just remember you need to get the polarity right when you solder on - I assume it's a 5mm LED just from looking at the pic.
  13. LEDs can be a little tricky, they have a voltage and maximum current requirement and come in various beam angles. The current is normally set on the board - the most basic way is with a series resistor, but can also be done electronically - too much current will burn out the LED. It looks like a standard 5mm LED and most of them seem to have a current spec of 30mA, but the voltage spec varies a little. These are typically pulsed in this service, so may be a bit more forgiving on specs. Are there are part numbers or any anything on the bulb itself? Probably unlikely given the size. Seems unusual to me that and LED would just fail, if they are setup right they are normally very rugged. See if you can find something like this locally: https://www.jaycar.com.au/red-5mm-cree-led-23500mcd-round-clear/p/ZD0293 23500 mCd is very bright.
  14. Ikelite sell a trim weight system: https://www.bhphotovideo.com/c/product/1445963-REG/ikelite_47140_trim_weight_system_for.html Maybe not that streamlined but possibly neater than sticking on balance weights. If you want the best streamlining you could always trade in an acrylic dome for a glass dome, which tend to be less buoyant.
  15. I would suggest pointing it out progressively - try a few stills shots when you first drop down, point it away until you lose the lighting then bring it back so you just get light on your subjects. Stills and video are not fundamentally different - if you light up particles they will show up in both stills and video. this link has some coverage of a single strobe. Fundamentally you want to keep the bright part of the beam (close to the light) away from the lens/dome. https://www.opticaloceansales.com/files/OOS-Strobe-Positioning.pdf 2-5m is probably stretching the friendship a little for a video light I would suggest - however if you a re video-ing distant stuff you want the light a long way off on a long arm.
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