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ChrisRoss

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Everything posted by ChrisRoss

  1. Assuming you are happy with condition of the strobes themselves and the reputation, size, performance etc. - I would suggest buying on the basis that you will need to buy two new battery packs. Li batteries are slow to self discharge but will eventually reach a state where you can't recharge them. Sitting idle is the biggest concern. In another words set the price on the basis you may need to buy new battery packs. This article talks about the issue: https://batteryuniversity.com/learn/article/low_voltage_cut_off If they turn on the above is not a problem. This article discusses ageing in Li-ion batteries and may be a useful read as well. https://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
  2. Quite reasonable result all things considered. on the foil, it would need to reflect the light into the aperture, the interior itself is like a matte silver colour so is already a bit reflective and foil wouldn't change the amount reflected by a lot I don't think. Something shaped like the reflector would be what you would want I think?
  3. It will be a metric thread and to get the size measure the OD of the threaded part - M6 x 1 screw is 6.0mm OD for example. best measured with calipers if you have them. If you look up a thread table it will give the common sizes and their pitches, a table like this: https://www.trfastenings.com/products/knowledgebase/thread-geometry/metric-coarse-standard If you have a sample you can take to a speciality fastener retailer to be certain.
  4. Optically this is correct and without any lens elements in the way performance is going to be equivalent to what it was on a native mount camera, but there are various electronics involved to allow for example a Sony camera to operate the diaphragm and the auto focus of a Canon EF lens. It has to translate the commands being issued from one system to another system. The main point is you need to read the fine print, the Canon 8-15 is reported to work very well on Sony and other cameras with the metabones. The Nikon mount sigma 15mm as another extreme example cannot be used on the FTZ adapter on Z series nikons as it doesn't have a focus motor. The AF for fisheyes and wide angle lenses in most cases is very snappy as it is not that demanding, macro lenses are more demanding particularly as you approach 1:1 and may not perform as well on adapters. Having reports from someone who has already done it is really invaluable and the adapter manufacturers will often report limitations for certain lenses.
  5. Depends on what parameters you look at - between the Rx100 and an EM-1 mkii you have about a one stop improvement in noise and minor dynamic range improvements. The main difference is having true macro capability if you fit a macro lens/port or a true fisheye. The housings are going to be bigger as they typically use the little accessory flash as a strobe trigger. The AF is probably better with an EM-1 mkII but maybe equivalent with an EPL model. If you use the 12-40 lens in a dome it will give you a nice improvement over the bare lens in a flat port with very nice quality throughout the zoom range and the ability to fill the frame with a creature 60mm across. My impression is that something like an EM-1 Mkii would be a nice improvement - like a mini DSLR in many respects, but getting one of the very compact EPL-10 setups, the improvements would be relatively modest, though it would give you the flexibility to use the 60mm macro or the 8mm fisheye.
  6. You might get close with good exposure/colour particularly at the higher ISO, but the other parameters will be a challenge. f2.8 is very fast for UW and there's really no wide angle solution which will not have mushy corners there. you might get f5.6 with a WWL/WACP type water contact optics. A fisheye you would probably want f8-11 and a rectilinear wide f11-16. The other issue is pointing such bright lights at a subject often causes it to leave, which may not be a problem with video but could present challenges getting into position for a good composition for stills. I would also expect you would want to be closer than a "few"metres - probably more like 1m.
  7. Interesting, is the impact purely flash range or is ability to keep the beam contained to avoid backscatter or both? The issue with the light shaper on the Retras is that most of the wide beam does not fit down the aperture of the snoot. It has a native 130°beam and the geometry is such that only a fraction of the beam goes through the aperture. the fraction that goes through is set by the distance from the tube to the aperture and the size of the tube.
  8. The rate limiting step may well be the availability of insurance, including evacuation insurance which will vary depending upon your country of residence and also depending where you propose to travel availability of flights might be an issue. Evacuation to a decompression chamber may prove difficult or impossible depending on where you are as well.
  9. The retra optical converter is manual only they specifically say TTL is not available.
  10. I was thinking the same thing that the mode should not impact upon manual triggering, because it only has to respond to a single strobe burst. It sounds very much like the classic S&S must have perfect fibre optic connections thing.
  11. As Tim alludes the TTL makes everything 18% grey, so the correct exposure for the shark in the example given is the same as the distance is the same but TTL would reduce strobe output with a frame full of white belly and increase it if there's not much white showing. And if the exposure is not right it's a guessing game as to what the camera did vs what you and the subject did to cause the exposure issue. I've not heard the term TTL used in any context other than automating flash exposure. Fibre optic triggering for TTL is not a new technology and has worked after a fashion for many years, mostly working better with macro. The ultra bright LED triggers are new but all they are doing is imitating an onboard flash and only recently have they had enough light output to do that.
  12. TTL to only adjust strobe exposure has been around for a long time, it's my standard approach for landbased macro shooting with strobes and has been for as long as I've been shooting digital and the ability to this is there UW as long as you have a TTL converter or an on board flash with an S-TTL (or equivalent TTL mode), which have been around for sometime as well. But underwater is a different story, the conventional wisdom is that TTL UW doesn't work for wide angle. much of the time the camera chooses to turn down the strobes or reduce shutter speed to pull more ambient light in. The important thing to note is that it is the camera that chooses what to do in TTL and has little to do with what strobe or TTL converter you are using. The strobe and TTL converter are only important in correctly interpreting what the camera has chosen to do. I am starting to see reports that some newer camera models are doing a reasonable job using TTL on wide angle shooting and this seems to be camera specific, which to me makes sense. The camera is what decides the ambient/flash balance. One of the bigger issues with TTL is repeatability - each shot the camera calculates a balance between the ambient and flash exposure and it may change with each frame if the subject size, orientation and framing change from one exposure to the next. With Manual exposure each frame gets the same flash exposure and there is a reasonable tolerance for distance. If distance changes too much maybe you also should have adjusted strobe position a little as well? For example a side on shark shot from below shows a lot of white belly. Another shark swimming past at a 45° angle and slightly lower shows mostly a darker back. TTL will change the exposure based upon reflected light when maybe it should have left the exposure constant. Sure there is some tolerance there to tweak the exposure in post but that's also there to a certain extent with a manual shot a touch further away.
  13. If you try it out take shots between f8 and f16 to see how the corners vary. The flat port would be quite ordinary in the corners and would only approach acceptable at maximum zoom, any dome will be an improvement over that.
  14. Meikon housings/domes are cheap for a reason, they sell something that allows you to get the camera UW and take photos, however, particularly with wide angle they always don't offer an optimised solution, they work , allow you to control the camera underwater and take a reasonable shot, but often they are not offering something that has the port in exactly the best position. The minor vignetting you report is probably not surprising and it's probably as good as you can expect. Looking at it from the photo it looks to be close to the right position, but without detailed measurements it's hard to tell. All I can suggest is taking it on a dive and trying it out. If the corners are softer than you like, you could try zooming in a little to close to 12mm. As you zoom in the corner softness will improve progressively. This is a common issue with any rectilinear lens this wide - APS-C cameras are a bit easier but still need to be setup properly to give their best performance. Changing to a 40mm extension would fix the vignetting but I would expect the performance to deteriorate - I assume it doesn't change length as you zoom? If you get UW and take some test shots and if the corners are an issue for you - you could come back and post some images and their settings we might be able to offer some suggestions from there. Pool shots in fact allow you to take a decent test shot to check for corner sharpness just get parallel to a wall and take a photo of the tiles at various apertures - they'll allow you to see how sharpness changes with aperture for one thing. If they don't have tiles take a couple of toys that sink to place in the corners or even a steel ruler or similar.
  15. HI Kerry, that seems like odd behaviour. I note t says this: " When it entered the customize mode to stand for 5 minutes without doing anything it will flash mode set by the mode switch. " Which sounds like the behaviour you are reporting - reverting after 5 minutes. Reading the manual I'm surprised if many people can get the mode switched to what they want - the turn of phrase is just a little confusing. Two suggestions for now. First up if you are shooting as you are now in two bolt manual set your flash exposure compensation to -3 stops, that will reduce onboard flash output by 3 stops which is about 1/16 power. Save a little battery that way. Second do you get the buzzer sound and green light when you change to mode B? The instructions say to power off the flash after you set it to B, so you would think it would stick. If it doesn't either both strobes are faulty or something in the sequence is wrong. Also just to confirm when you say does not fire - that means no triggering at all ? or just that the strobe does not show in the exposure. As far as I know getting the mode set to B only fixes the second problem with the strobe firing and not syncing correctly with the camera. Also just to confirm you have RC mode turned off - shooting menu 2 last item. That's a custom mode for Olympus flashes must be off for this situation. Thanks too on the photo - you talking about my avatar ? it's giant cuttlefish off Sydney you can find a big version on my website.
  16. I seem to recall some Sony models has 1/160 sync by default and would allow a higher speed if a Sony external flash was installed and some trigger setups take advantage of that.
  17. well that's always going to be the case, the dome gets in the way of getting closer. It probably makes little difference if you are not in microscope mode. Subtle distinction, but probably a practical limit for a great many subjects.
  18. What does the port chart say - which brand of dome? The main impact of being too far back in the dome would be vignetting - if it doesn't vignette , it's close to the right position by the look. It looks like a 180° hemisphere dome so the centre of curvature is close to the dome base and you can see the entrance pupil which looks like it's very close to the front of the lens. at the 10mm end particularly, you will still need to stop down to at least f11-13 to get sharp corners.
  19. I have to agree. I can't imagine a dual sync cord costing more than 50% of the price of a trigger and once you have the trigger you need cables as well.
  20. Does the manual specifically mention fibre optic ports? Looking at the housing on the website I can't see any fibre ports - in which case it is sync cord only. If I am not mistaken you can only do manual flash via wired connection on an INON unless you buy a wired TTL converter. Before leaping in to purchase a converter if that's what you want, you would need to check if there is enough room to mount one in the housing. How much is the dual sync cord, it's sold out on the seafrogs site, but a single is $95. It's probably cheap compared to a TTL converter. Again I suspect wired connections is your option, so any TTL trigger will need a wired option. Or just learn to shoot manual flash and use the plain sync cord. As to which strobe to buy the S-2000 is too small, you'll want plenty of power, you will probably want to shoot the 16-35 at f16 in that little 6" dome and even then the corners will probably be soft, so that'll need plenty of strobe power.
  21. Moved to Strobes and lighting. I have the EM-1 MkII my setting is 1/64 in manual and it's very reliable as long as I have the strobe on the right settings, but with INON strobes which are easier to trigger. So you say you are now using fill in? which is TTL on the camera with the strobe at double lightning bolt manual? That will certainly work, but is probably often setting off the on-board flash at near full power and using more battery power in the process. Is it possible you thought you were in B mode before and now you have actually switched it on the strobe? Might be worth trying manual at various powers again? I would suggest though that you save the settings in camera as they currently stand to a custom mode so you can recall just by turning the dial to that position, before you do anything else. If you try manual again, the camera flash should be in manual - try a few different powers and the strobe in single lightning bolt manual.
  22. I doubt it, the lights you are talking about are not that bright. I mentioned the apertures available as it is not made clear in the manual that is what is happening. The program modes will use the ND filters sometimes - so I would suggest Av mode as a default and switch to microscope mode if needed. You can test it on land as well - just do inside, the ambient light is reduced and it should give you an indication of what it will try to do UW.
  23. The difference between light and strobes is huge, a 15,000 lumen light is about 6 stops less bright than a strobe. So I don't think you'll have problems with too much light, but to get enough you need to be close. The TG-6 has two apertures f2/f4.9 and f2.8/f6.3 anything beyond f6.3 is using an ND filter. If you are doing macro I guess you are zoomed all the way in so maybe using f6.3. That's a little slow but not too bad. A bright light in close should be OK, but adding more wouldn't hurt. You don't say what settings you currently use, that might help us guide you a little better. so shutter speed, f stop and ISO.
  24. Moved to Classifieds. Please don't post items for sale in other forums. Also please do not post duplicate ads. The rules allow you bump the ad once per week.
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