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ChrisRoss

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ChrisRoss last won the day on March 28

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About ChrisRoss

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    http://www.aus-natural.com

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    Sydney Australia

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

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  1. It probably won't be a problem to use the energisers for a while - the eneloops are supposedly what helped INON solve a reliability problem due to heat buildup. If you rapid fire full power dumps constantly it could give you a problem , but casual use for a short period probably not?? I think you are using a TG-6 if I remember your other posts shooting that for macro using f6.3 (not the f18 option) should mean you are at quite low power which is easy on the flash. What you will need to do is charge them each outing if they have been sitting more than a few days as they self discharge.
  2. Eneloop is generally regarded as best but INON have a list of other acceptable batteries. It's in the manual, : Sony cycle energy blue Panasonic HHR-3MPS Imedion (MAHA) MHRAAI4 (they also make an excellent 8 cell charger) GP batteries ReCyko+ - 210AAHCBE ANSMANN AG maxE - 5030991, 5030992 5035052 Electrochem NEXCell energyON - AA 2000 mAhr are listed in addition to the eneloops and eneloop Pro. Your strobe probably won't die with energiser, but they will get hotter and are also prone to rapid self discharge. Probably a longer term thing - but I would get eneloop anyway and use them once they arrive and relegate the others to a dive torch or something once you get the eneloops. Depending on how many dives you do in the time the eneloops take to arrive you could use a set of regular AA energiser (disposable), you'll probably get two dives from a set or more if you can get the AA Lithium cells - both are listed in the manual as a battery you can use.
  3. well whatever they do they need to get to 2200 deg C or so. Classic way to achieve that is an electric arc furnace. I wouldn't think you'd need a lot of heat to dimerise acetylene then add HCl unless the reaction is particularly endothermic?
  4. Open ended question - really depends on where you are from - if there's Covid active there still likelihood of travel is low realistically. There's no diving local to you?
  5. Hi Bill, agree, I don't have direct knowledge about the calcium cycle - the CaOH2 from step 3 is probably a finely divided suspension mixed with all the stuff in the Calcium carbide which is not carbide - I think the carbide comes out as about 80-90% carbide - the rest must be something else- probably silica and alumina?. So whether it is recyled or not depends on how difficult it is filter out the CaOH2 from what is left - it may be more cost effective to sell the slurry as agricultural lime? There may also be some nasty by-products from the acetylene mixed in - that is an extremely reactive molecule. I found an article on a study on the CO2 footprint of using carbide sludge in cement kilns vs fresh limestone which tends to indicate it is a waste product - it reduces CO2 emissions compared to mining limestone as you don't get the CO2 emission from the limestone and you don't mine and crush it, but you do have to dry it. I agree about the chloroprene - there may be better processes you can use and you can use that process whatever the source of chloroprene. A lot of marketing for wetsuit material is dubious - take all these claims of reflective layers reducing radiant heat loss - radiant heat loss is not a thing for underwater - I could go into a lot of detail why not - suffice it to say that the temperature difference of the radiating body - you in your wetsuit - to the environment is very low so the driving force for radiant heat loss is minimal. Convective and conductive heat loss dominate. The point is don't believe the marketing all you can go on is reviews about how people like the product - compared to what they had before.
  6. I think what I was trying to say was AF on the adapter for the 8-15 fisheye for example might be acceptable but would suck on a macro lens as you said. The problem is no way to predict the performance unless someone else has tried it out - all you really can be sure of is it won't be as good as the same lens on a D series Nikon.
  7. I don't shoot any of these cameras but I would tend to go with what you know, early adopters always pay a premium to be beta testers. Having said that the main shortcoming seems to dedicated lens availability and AF performance. this is how I would look at it: Lenses on the adapter will be optically the same as what they perform on a DSLR - there is no glass in it just a spacer the advantage of dedicated Z lenses will mainly be wide angle - optics tell you that - a non retrofocus design has better opportunity to be sharp. But that extra resolution and definition could well be lost on UW wides due to issues with dome port optics. AF on the adapter will likely vary from lens to lens AF for wide angle work (reef scenes, CFWA) on the mirrorless bodies is probably already OK - it's not very demanding AF on macro or perhaps fish portraiture or seals for example where fast AF is needed is where you will see any penalty The lifetime of the EVF should be no different to the rear LCD - the reliability of which is probably no better or worse than shutter and mirror reliability and almost certainly more reliable than mechanical connections to stop down the aperture on older lenses and AF motors on any lens. On the pixel dumping it sounds like a great argument except it ignores the fact you don't have to use all the resolution. The Z6 and Z7 will be near identical if you down sample the Z7 to Z6 resolution, you gather the same amount of light with both so image quality should be so close as to be indistinguishable apart from fine detail on very large blow-ups. You might be able to crop the Z7 a little more and blow up to larger sizes but... In underwater work particularly with full frame people stop right down to deal with dome corner sharpness and you are in diffraction and losing some of that extra resolution. My feeling is that for most lower resolution will be fine for UW shots for most people - but there are certainly those who can make use of it. For now I would think you can either pickup a second hand D800 as a stopgap to last till Z6/Z7 mkII come out or the D860.... or go with a something new. On the something new if AF is important to you a D850 is known quantity and will certainly produce great shots. The Z6 or Z7 will also do fine if you can live without the AF of the D850. Where I see advantages for mirrorless is brighter viewfinder images and features like focus peaking to help with focus.
  8. To follow on from what Phil said, the port chart says effectively add any canon lens with metabones adapter using the extensions and domes recommended for using those lenses in a Nauticam Canon housing. Effectively once you add the 100-120 adapter and Metabones adapter treat the combination like a Canon housing and use the Canon port charts and of course this extends to the Zen port charts. So you can add anything Canon based on this chart : http://www.jaredparsons.com/portchart/zen-only/by-combination-group/nauticam-n120/ That's not to say it will work well just that it will fit and perform optically like it would on a Canon system. It depends on how well the lens in question plays with the Metabones adapter. Bear in mind some of the options might require fitting the port over the lens as the lens/zoom ring may not fit through the N100 housing if they are too large in diameter. This also applies by the way to the Micro43 system which has a similar entry on the port charts- so you can add a Canon 8-15 to a micro43 system which is particularly interesting as the whole zoom range is available.
  9. These suits are advertised as being made from Limestone - this is in reality quite a stretch. I have a background in process industries and I can tell you that there is no actual limestone in the neoprene material. A long story follows for those interested. The process starts with limestone and a source of carbon I believe the Japanese made one uses old tyres. Limestone is calcium carbonate and it first reacts to make lime - calcium oxide, releasing the CO2 that is bound with the calcium. The calcium oxide reacts with the carbon source at very high temperatures - 2200°C. The reaction makes calcium carbide: CaO + 3 C → CaC2 + CO . The CO would need to be combusted to CO2 or used in another process. Next step is to react the Calcium Carbide (CaC2 ) with water to make Acetylene and Calcium hydroxide. The Calcium hydroxide is a waste product but could be used for agricultural lime for example - I don't know if it is or not it is a low value product. If they recycled the lime that I think would be a positive step from a green perspective. Once you have the acetylene - this is the gas used in oxy-acetylene welding and cutting - you can then react it with chlorine to make chloroprene which is polymerised to make neoprene. Conventional neoprene is also made from chloroprene but the chloroprene is made from butadiene which is manufactured from petroleum - a by-product of the refining of petroleum and chlorine or hydrochloric acid. In fact when it was invented in the 1930's neoprene was made via the acetylene process but had odor problems that were easier to overcome making via the petroleum route. Effectively what happens is two acetylene molecules react to make a compund similar to butadiene that can be reacted to make chlorprene. So both types of neoprene start from the same building blocks: you see claims that the "limestone" product has superior properties but if they both start from the same building block -that is chlorprene- oil based neoprene could use the same reactions. So where does this leave us?? - both processes are energy intensive I don't have the numbers but my educated guess is that the limestone product has higher energy input to achieve the same product - but the raw material is in fact old tyres and this is probably a better use for them than landfill or burning them - it is a form of recycling. I would say that if you like the properties of the suits over conventional suits - use them. But don't claim they are made of limestone and are somehow magically a lot greener. They in fact are made of old tyres which is a good thing but maybe not as marketable perhaps as trying to claim they are not made from petroleum. I have not been able to find any analysis on the greenhouse footprint differences in the new technologies but my gut feel is that the limestone process is more energy intensive. If they made it in a solar furnace that would be a clear advantage I think and definitely tip the scales in favour of the new product. There is also Yulex, which is a made from natural rubber (85%) which is a renewable resource, but utilises agricultural land to grow rubber trees. It is certainly less energy intensive.
  10. The last entry on the Sony N100 port chart https://drive.google.com/file/d/1YRwHfXvXLqWK3NsfXjtGbm7gSEmAw4g0/view has an entry for the metabones adapter and then refers you to the Canon N120 port chart. What this means is you use the N100-N120 35.5mm adapter and then use the recommended ports and extension for the Canon 8-15 in the Canon port chart which is the Canon 140mm dome and 30mm extension. The adapter has a zoom knob, so presumably the Canon zoom gear mates with this zoom knob - you should check that with your supplier or someone using the combo may be able to confirm this for you.
  11. I found Garuda very good, when I put the bag on the scale they asked is that scuba gear? Free 23kg allowance for dive gear. I booked on Garuda's website and prices there were quite OK.
  12. It looks like the tool is just a straight bar that slots into openings on the front of the port, so any straight piece of metal could be substituted and maybe wrap the part over the port glass in a cloth. An alternative might be a strap wrench - you have to careful that the handle of the strap wrench does not dig in as you try to turn and placing piece of neoprene or similar underneath that area will help protect the port. If you use a strap wrench - go gently and once you get the port off check the o-ring carefully - lack of lubrication may damage it as you turn the port.
  13. I certainly notice many fish will move on when I point my focus light at them, so I have taken to turning the light on only when I need it. This light is rated at 700 lumens and has a 60°beam. I am toying with going back to my older torch of 350 lumens - not much output you might say but it's certainly more than adequate for focusing at macro distances when I'm under overhangs or in caves. Shooting video of course is a different issue as you need much more light and a few more lumens helps penetrate poor viz and deeper into overhangs for focus and spotting lights.
  14. Moved to the lights and strobes forum, should get more people looking at the topic. - hopefully some who have practiced using red and blue filters. On your questions, I'm no video specialist but I would suggest maybe 20m is the maximum depth - you basically start to run out of red light as you get deeper and if the water is green perhaps a magenta filter would be best - depending on just how green it is. It will depend on how sensitive the camera is to red light. I would think a custom white balance should be done with the filter on as that is the light you want to record. The video light is filtered blue so it matches the ambient light - without the blue filter anything illuminated becomes very red. The issue you will run into is that the colour returned from the light changes as your subject distance changes as the light has to go to the subject and come back again so your white balance target should ideally be out at the same distance as your subjects. If it's not arguably it's better to WB without the lights. I don't have a feel for how noticable this shift is though. The last point is that for the type of shots depicted in the video the subject is distant so your lower lumen output lights will have reduced range compared to the 10,000 lumen lights. One final point for the TG-6 - at its widest it has two apertures f2 and f2.8 you can dial in f8 but that is achieved with an ND filter so it just sucks up light - you probably only want to use f8 to reduce the shutter speed in bright shallow conditions or with a strobe to help give a black background.
  15. Welcome to the forums! Housings you can get but only a limited array of lenses that are good underwater, Nauticam made an XT-1 housing but now discontinued, they sell them for XH-1 and XT-3 and those housings use the bigger N100 ports so better for large wide angle lenses. The Port charts can be found here: https://www.nauticam.com/pages/port-charts
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