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dreifish

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Everything posted by dreifish

  1. I don't have side by side comparisons underwater of the m4/3 cameras I used and the FF ones, so it is hard to do a quantitative analysis of the differences. The inherent compression and 8 bit nature of internet display also hides some of the differences you might observe with original raw files printed large. Not to mention that a lot of the overall impact of an image comes down to the quality of the post-processing techniques used. My portfolio ( https://www.andreiv.com/Portfolio ) has images from the GH4, D800 and A7RII in there. If you can't easily identify which camera was used, then perhaps you shouldn't be worried too much about image quality differences. As Phil says, m4/3 images are good, or good enough. 36mp+ full frame images are fabulous though. But that's also something that is more easily noticeable when working with the raw files in lightroom, for example than it might be in the published photos.
  2. Seriously? Do we need to get into citing specific case law in California? The exemption to the general rule you're relying on requires not merely definite terms, but also, to quote the article you linked, that the offer "is communicated to a specific person or persons (usually limited group of people)." (emphasis added). There are plenty of cases out there holding that advertisements in a newspaper or catalogue in general circulation don't meet this requirement because they are not directed to a limited group of people and theoretically could be accepted by more people than there is inventory to sell. The situation with a forum post is analogous. You'd have a much stronger claim if you had received the offer in a private message from the seller, but those aren't the circumstances here. For all you know, someone could have contacted the seller by private message, email, telephone or some other means before you did, or multiple people could've "accepted the offer" simultaneously. When an advertisement is directed to the public at large and not a limited group of people, you'd have a hard time convincing a court that the advertiser intended to enter a contract as opposed to inviting people to make a deal. The exemption further requires that "the circumstances surrounding the publication show that the advertiser has the intent to enter into a contract." and the article goes on to explain that "the main factor that most courts look at is whether the parties had the intent to assume legal responsibility of entering into a contract. However, different courts have different ways in dealing with this issue." Given the general understanding of the community about how online classified posts work, I think you'd have a very hard time showing that the seller had an intent to enter a contract with the first taker just based on a forum post. The seller could very well have had reservations about the first responder's ability to pay, ability to pay on time, etc. that would weigh against construing such an intent to contract merely on the basis of a post that contained the price.
  3. Sure, for macro subjects that aren't bothered by strong continuous light in their face, I mostly agree, if you're willing to work at higher ISOs and get lower quality images than with strobes. Remember that for macro you end up having to shoot at rather narrow apertures -- F16+ on full frame -- and without a strobe to freeze action for you you also have to keep your shutter speed higher. Probably 1/100 at a minimum, unless you're limiting yourself to a tripod with a static subject. I think that easily puts you in ISO 800+ territory even with strong video lights. LED lights are easier to snoot than a strobe at least, since you see where the light is falling.
  4. Basically, if you remove the ball mounts on the handles, height is the same as GH5 rig. Width only slightly wider. Looks similar to the nauticam housings for full frame DSLRs (D850, not D5). Price is the same too Look forward to hearing what you make of it, Richard.
  5. In terms of the funky colors, the main issue I observed is pushing a bit to much towards the red in certain reef scenes, which introduces a noticeable magenta color cast into the water column, too. So if I understand correctly, you 1. Kept the camera set to either auto WB or underwater WB; 2. Did not use a red filter on the camera; 3. Did not use a blue filter on the lights; and 4. Did not do any color correction in post or increase the saturation in post? What picture profile were you using? Basically, I would not recommend using the underwater WB mode with the video lights, as underwater WB will set the WB too warm for subjects primarily lit by your lights. That could account for the red push in some of the shots. Auto WB or fixed WB (5500k) would work better for shots primarily lit by your lights. In terms of exposure strategy, I would actually try to keep the lights on full power unless the ambient light conditions are /really/ dark. Basically start around F8, 1/50, ISO 400. I doubt your lights on full power would cause overexposure at such a setting. If you find that this produces a water column that is too dark, then raise the ISO and lower the power of the lights to avoid overexposing the foreground. If the exposure is too bright, leave the lights on full power and lower the ISO first. If still overexposed at F8, 1/50, ISO 100, start closing down the aperture further until F16, then start raising the shutter speed. I can't think of any conditions underwater where F16, 1/100, ISO 100 would cause overexposure from either the ambient light or the artificial light, even at midday in shallow water.
  6. Well.. yes and no: 1. Zoom range would actually be better with the WWL-1 and a 14-42mm kit lens: 10mm-30mm equivalent vs 10mm-25mm equivalent with the WACP + 28-70 lens. Both can focus on an object touching the front of the glass. 2. You'd lose two stops of dynamic range, but more importantly, you'd lose significant resolution from the higher megapixel sensor and better optics. Also you'd lose color depth. I've shot on a GH4, GH5, D800 and A7RII underwater. For stills, the files from the high megapixel full-frame cameras definitely are nicer. But the GH4/GH5 shots are good enough if you're not a pixel peeper or a snob. Odds are your skills are going to hold you back much more so than the camera. 3. The Olympus E-M1 II comes with an included accessory flash that fits inside the Nauticam housing and can do TTL optical TTL with the YS-D2s using standard optical cables. 4. Macro choice depends on your subject, so no, there's no universal choice. All three can do 2:1 magnification (in full frame terms), but with varying working distances. The 30mm is more versatile if you want to also do medium fish portraits, while the 60mm is probably the go-to for super macro subjects but otherwise is too tight for most subjects in my experience. The 45 sits somewhere in the middle. You could potentially use all three in the same port with the appropriate extension rings, which gives you great versatility. But I suppose the Nikon also gives you a 60mm and 105mm option. Finally, if you get the YS-D2s, get the Japanese version, the YS-D2J. Too many issues with the original Chinese manufactured ones to recommend them. You should also consider the INON Z330s.
  7. Basically, there's a few different tiers in terms of underwater setups: Tier 1 (under ~$1000) - GoPro 7 / Olympus TG5 GoPro 7 + housing - if shooting only video. Terrible for stills, no option to use strobes. Olympus TG5 + housing + wet wide angle lens like bakscatter m52 lens. Great for macro on its own, can take decent wide angle images with a wet lens. A good starting point for most people who want to get into underwater photography and not monstrous to travel with. Main limitation for me isn't the sensor size, because image quality is really good enough at ISO 100 for anyone who isn't printing poster. Rather, it's the lack of a full manual mode, which can be frustrating once you start introducing strobes and doing balanced light wide angle photography. You can kind of work around this limitation by using aperture priority mode, fixing the iso and then using exposure compensation to indirectly control the shutter speed, but it's not a perfect workaround. If the TG6 introduces a full manual mode, I would strongly consider owning one of these cameras even as a professional. The macro mode is great! Tier 2 (around ~$3000) - Sony RX100 or Canon G7X II or Panasonic LX 100 1" sensor compact + wet wide angle lens and wet macro diopeter The main advantage over a TG5 for me here is the full manual control. Image quality is better as well, but honestly, I think the TG5 is good enough for most people as far as image quality is concerned. But the tradeoff is that now you need a wet diopeter lens to do macro, and the macro magnification isn't as good as what you could achieve out of the box with a TG5. You're also looking at 3 times the cost once you factor in an aluminium housing and a good wet wide angle lens like the Nauticam WWL-1. Tier 3 (~$6000) m4/3 Mirrorless Cameras like Olympus EM1 Mark II or Panasonic GH5 The big step up here from the 1" sensor compacts is the ability to use interchangeable lenses. m4/3 has a great lens selection, with everything from 180* fisheye lenses, to kit lens + WWL-1 wet lens for wide angle, wide angle lenses behind a dome port (mainly only consider if you do a lot of split shots, otherwise the WWL-1 route is a better option) to dedicated macro lenses that can get you 2:1 magnification without any diopters. Image quality isn't actually a huge improvement over the 1" sensor compacts, but ergonomics on the housings are better. For video, I consider m4/3 to be the sweet spot atm. For photos, there's an argument to be made that some of the cameras in Tier 4 offer sufficient improments in image quality, autofocus and lens selection to make them worth considering. Tier 4 ($8000+) - APS-C or Full Frame DSLRs/Mirrorless Cameras Main advantages here over m4/3s are: * better autofocus systems (mainly in the the Nikon d500/d850/d5 line); * access to versatile fisheye zooms like the Tokina 10-17; * significantly higher resolution and IQ with the 40-50Mpix sensors * optical viewfinders (which are easier to compose high-contrast wide angle shots with than EVFs, in my view) But there's some real disadvantages as well: * depth of field for macro is shallower than with m4/3 cameras, and you get less magnification without external lenses * if you use wide angle rectilinear lenses behind a dome port, you need a 230mm dome port for the best results, and these are huge, heavy and expensive * the WACP wet wide angle solution is very heavy and very expensive also, when compared to the WWL-1 you can use on m4/3 * heavier and bulkier for transport, even though the whole overall rig might be similar in size in the water It's worth also considering that a lot of the perceived quality improvements underwater come from your lighting (strobes) and getting closer, not so much from the camera sensor size or even the quality of the optics. And once you add two strobes, a tray, arms and a wet wide angle lens, even a TG5 rig gets quite big and bulky. I wouldn't say there's a meaningful difference in size between a compact, m4/3, or even a full-frame camera once you add arms and strobes. At least, not if you stay away from 230mm dome ports and use fisheye lenses with smaller dome ports or wet lenses for wide angle.
  8. Nice work I think this technique is actually more effective with strobes for photos than it is with video lights since strobes put out a lot more light and thus aren't as sensitive to the light loss from sticking blue filters on them. Odd that it didn't really catch on for wide angle photography yet somehow is suddenly all the rage for video.. Curious to hear what you ended up using for blue filtration on the strobes and how you did the calculation. Also, shouldn't this theoretically also work in greener water if you combined 'green' filters on the strobes with a magenta filter on the camera? Same principle -- magenta filter helps with white balance to the ambient conditions, and green filters bring the color temperature and tint of the strobes into the same ballpark as the ambient light filtered by the temperate waters?
  9. That's 160 degrees in air, or 120 degrees in water (since they use a flat front, not a dome) I suspect. Nonetheless, unless you're filming with a fisheye lens a 120 degree beam angle is not actually necessary since a lot of that light will fall outside the angle of view of your lens. With a typical rectilinear wide angle lens and 2 torch setup, a 90-100* beam angle is plenty and will concentrate more of the light in the area you're actually filming.
  10. Careful -- those battery packs on the Big Blue CB15000P are 134Wh -- they're going to be very difficult to fly with. Most airlines restrict you to 2 <160Wh batteries, but it depends -- some don't allow them at all.
  11. There's a 20% discount on the Jaunt G18 Plus on Alibaba atm.
  12. I've never done a precise measurement (and I wish I had taken side-by-side photos) but when I tested the the Keldan Luna 8x, it was noticeably less effective at restoring color than the Gates GT14s in water. If the 8x is really outputting 6500 candela compared to Gates' calculated 7600 candela, that's only a 17% difference.. it should've barely been noticeable at all, and it definitely was noticeable. I'd rate the difference as somewhere between 1/2 and 2/3 of a stop.
  13. UW3D -- there's no formal legal offer to contract at play here, merely an indication to enter into preliminary negotiations. Courts generally consider an advertisement as an invitation to enter negotiations, not a definite offer that can create a contract. If you're going to try to impress us with your legal analysis, at least get it right... I don't think the for sale post can be construed as showing present intent to form a contract. You knew (or had reason to know) that the general practice on forum classified boards is for perspective buyers and sellers to negotiate the details of the sale, shipping, etc. before entering into a formal agreement. Furthermore, breach of contract is a civil cause of action and Wetpixel is under no obligation to share any details with you regarding other issues. Indeed, I think having a policy that allows sharing of user details in such a circumstance is ill-advised. It would mean the administrators have to evaluate each case and decide if the person asking for personal information is telling the truth about the situation or is fabricating the whole thing. Much better to categorically not share private information about users absent a valid subpoena.
  14. Shallow, clear water with plenty of sunshine and white sand to bounce that sunshine and fill-in the underside of your subjects is pretty much ideal conditions for ambient-light only shooting. There's no way a pair of Keldan 8x's with blue filters (which cuts their light output by at least one stop) would be able to put out enough light to matter in such a ambient-light rich environment. You'd need the ambient light to be at least 3 stops darker before the Keldans would begin to make a difference. Image quality looks nice to me. Did you shoot in cine-d, or the standard profile? Not really sure that there's anything here that color-grading could add. You could increase the contrast a bit by brightening the whites perhaps, but it's not like you're dealing with very colorful subjects. Looks pretty natural to me. I assume this is around 10 meters or so depth? Even the yellows tails of the fusiliers are pretty washed out, because the warmer wavelengths just don't really penetrate that deeply. One thing I did notice a bit is the barrel distortion of the WWL-1 when you're panning and don't have the 'horizon' perfectly centered in the shot. I think you'd have to zoom in a fair bit to mitigate that though. Some suggestions for future work that will give you more options in your edits: 1. Let the subject swim in and out of the frame while maintaining the camera position fixed rather than always panning with them; 2. Remember to shoot medium and tight shots in addition to the wide angle shots. You have a zoom lens behind the WWL-1. Use it, it's one of the biggest strengths of your particular setup
  15. My setup is basically 8" + 5" (approximately). I also use a pretty long clamp between the two arms meant to work with wide float arms. and 90 degree beam lights and WWL-1. So if I was to fully extend the lights out horizontally, they'd be about 20" out from the lens. Going by the rule of thumb that your lights should be the same distance away from the lens as the subject is from the lens, this lets me work with subjects between 6" to ~20" with no beam overlap before the light hits the subject. I've found that to work quite well, as the lights don't really output sufficient power further away than 20". Video lights are about 5-6 stops weaker than strobes (at best). So backscatter is less of a concern with video even if your light positioning isn't perfect. I've never felt the need to have wider arms. Keeping the lights closer to the body of the housing (and potentially using a single arm instead of a double-arm setup) would greatly improve how the rig handles in the water (especially in current!). I only use the floats I use because the housing and lights are so damned negative otherwise.
  16. My main take-away from that sample is that at depth, without lights, you're not going to get great results regardless of whether you do a custom white balance in situ or shoot raw and do a custom white balance after. This footage appears to be shot below 10 meters, so we can't really expect amazing colors. The water clarity may also account for the desaturated overall look (or it could be a conscious decision made in the post-processing). I agree though that this particular clip doesn't showcase anything that couldn't be achieved on a GH5 already. Stability looks decent (at least there's no distracting micro-jitters). Highlight rolloff looks quite organic. Having the option to set white balance in post adds a lot of flexibility, even if it doesn't necessarily allow you to achieve anything you couldn't already do with a GH5 if you properly set custom white balance when shooting. The purple water column (e.g. at 0:22) is concerning though and does remind me of the GH4 results as well. Interested to see what the camera can do in clear tropical waters..
  17. I think Barmaglot does a great job of outlining all the reasons why LEDs aren't going to be matching the capabilities of strobes underwater any time soon. In my own testing, a YS-D2 is about 6 stops brighter on full power than the 14000 lumens Gates GT14. (And this is allowing for a 1/60s exposure with the LEDs). And better ISO capabilities of cameras don't make any difference. The problem we're trying to overcome underwater isn't a lack of light -- it's too much cold ambient light. We need our artificial light to be powerful enough to outcompete the ambient light. Zenon strobes that output all their illumination in one very short burst do a much better job at this than LEDs that output light continuously. The amount of light an LED can output in the same time frame as a zenon tube is several orders of magnitude weaker than what a flash can do. LEDs aren't going to be replacing zenon flashes in our lifetime, if ever.
  18. D850 has some major advantages underwater if photography is your main focus. OVF is much better for composing wide-angle shots than EVF/Screen which has limited dynamic range Z7 focusing with the adapted 105mm for macro is pretty bad. D850 focusing for macro is class-leading, and 3D tracking is very useful in this scenario since you can't use the joystick or touchscreen underwater 1/320 flash sync speed on the D850 vs 1/200 on the Z7 gives you 2/3 of a stop extra to play with in terms of lowering the background exposure for surburst-type WA shots Only reason I'd consider the Z7 for underwater use is if video is a significant portion of what you do. Even then, I wouldn't consider it for the continuous autofocusing (which likely will not be reliable enough to use underwater) but merely for the sensor stabilization. That's quite nice to have for video. IMO, stabilized footage looks so much more professional/better.
  19. Awesome! And now we have BMRAW internally, so the combination with the 5" monitor seriously reduces the need for an external monitor/recorder. The housing is more expensive than I'd like, but I believe it comes in at the same price point as the old Black Magic housings Nauticam made and very similar to their DSLR housings, so part of that may be the size of the thing. $3900 for the housing. + $1300 for the camera = $5200. A GH5 would be $1450 for the body + $2850 for the housing, so around $4300. Not such a huge difference in the end. Certainly cheaper than getting a GH5 + housing + Ninja 5 + housing (if that ever becomes available) or a Nikon Z7 + external recorder to get ProresRaw. Looking forward to samples of what it can do underwater. I'm sorely tempted to buy one. And BMRAW integration into FCPX.
  20. In order of importance, if you're looking to improve your photos, I would recommend the following steps: 1. Get close. Even closer. Unless shooting macro subjects, shoot a the wide end of your lens (don't zoom in -- get physically closer) at the lowest ISO possible. Get a wide angle adapter to allow you to get even closer to your subject while still keeping it in the frame. This is going to do a lot more to improve the quality of your images then getting a new camera would. 2. Get a strobe. Initially it's quite fine to start with just one and master that before getting a second one later. With proper technique and lighting, you can get amazing results from the TG-4.. basically as good as you can expect from any larger camera. A different camera won't enable you to take better photos, but a wide angle adapter and lighting will.
  21. Best prevention for baurotrama is to pay attention to equalization when descending, especially near the surface. Focus on that when you initially start the dive rather than fiddling with a camera. Descend slowly, equalize often. Some thing during the dive when you're taking photos.. pay more attention to any changes in depth you might be making while absorbed in the camera. I can't count the number of times I've followed a subject to get the shot (especially on video!) and ended up making large depth changes without equalizing. It wrecks havoc on your ears
  22. Don't have any of these domes to test, but if I remember correctly, GoPros have a minimum focus distance of around 30cm. An air-filled dome underwater will create a virtual image inside the dime that is closer then the go-pro's minimum focus distance, so the image will be out of focus. The only way to correct it would be to put a diopeter on the go pro to allow it to focus closer. Basically, these domes aren't designed for use underwater, just for split shots where you don't care if the underwater portion is in sharp focus.
  23. Don't have any of these domes to test, but if I remember correctly, GoPros have a minimum focus distance of around 30cm. An air-filled dome underwater will create a virtual image inside the dime that is closer then the go-pro's minimum focus distance, so the image will be out of focus. The only way to correct it would be to put a diopeter on the go pro to allow it to focus closer. Basically, these domes aren't designed for use underwater, just for split shots where you don't care if the underwater portion is in sharp focus.
  24. I've never used tho WACP, just the WWL-1, which as far as I know has an identical optical design, just smaller. So consider it a baby WACP. The WACP is a 0.36x magnification wide angle converter. So it turns the 28-70 into a 10-25mm lens essentially This is a 2.5x zoom, so you're correct that it has a wider zoom range than the 16-35 (that's a 2.2x zoom), but it's actually wider than the 16-35 both at the wide end and the telephoto end. So if you need the reach of the 35mm, the WACP can't reproduce that. This may be a factor with shier sharks in the red sea. (The WWL-1 + 14-42 combo on micro 4/3 is actually slightly more versatile because the lens is a 3x zoom, giving you a 10-30mm FF equivalent zoom range.) Rectilinear ultra-wide (weitwinkel) angle lenses like the 16-35 stretch objects near the corners of the frame. I personally find this very distracting (especially for video) and an unappealing aesthetic. You don't get that with the WACP, which has a mild barrel/fish-eye distortion near the edges. I find this looks a lot more organic/natural and less objectionable underwater unless you're dealing with a subject that has lots of straight lines (e.g. a wreck)
  25. Yeah, that's definitely something to consider when looking at the more powerful light options, and something I mentioned in the initial post. I asked Jaunt about this specifically with regards to their G18 Plus lights and they indicated to me that they've now redesigned them to use a 97Wh battery to avoid just this particular problem. So my initial table is out of date in that regard.
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