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ChrisRoss

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Everything posted by ChrisRoss

  1. If you are using the viewfinder to compose there are a few options to get a magnifier for the LCD screen and these often have dioptric adjustment, lets you use the screen like a viewfinder with your distance vision. Your options will depend on what housing you use - Nauticam compact housings for example have mounting points for their LCD magnifier and AOI make one for the TG camera housings.
  2. I found some issues with purple fringing with the Pany 8mm, on my EM-1 MkII. Apparently the cut off filter for UV is different between Pany and Oly with the Olympus letting through wavelengths that the Pany lens does not fully correct for. Doesn't appear on all shots, most noticable with bright objects against dark backgrounds. The Capture One Pro purple fringing tool can remove much of it. If I was doing it again I'd get the Oly lens. I had a post on that here: I was also thinking the corners were quite soft but have since decided that is due to the corner in question being much closer and falling outside the DOF. The shot in question was along a wall and the wall itself was much closer than what I was photographing. I use the Pany 30mm macro, AF is quite snappy, noticably better than the 60mm macro, haven't used the OLy 30mm to compare. You can't take advantage of the extra magnification (1.25x) on the Oly as it focuses almost on the port glass. In fact I think the practical limit for lighting with the 30mm lenses is about 0.5x as you are getting so close to the port glass it is diffciult to light. Where they shine is for larger subjects - small fish size up to about a 300mm long subject. The working distance for such subjects is too great for the 60mm macro - too much water between you and the subject and much higher chance of backscatter, particulatlry in temperate waters where I shoot often. Some examples: Fish 20cm long: http://www.aus-natural.com/Underwater/Bony Fish/slides/Senator Wrasse 3.html Fish 12cm long: http://www.aus-natural.com/Underwater/Bony Fish/slides/Blotched Hawkfish.html Nudi 5cm long, 50% crop: http://www.aus-natural.com/Underwater/Nudibranches/slides/Hypselodoris bennetti.9.html Nudis 4cm long: http://www.aus-natural.com/Underwater/Nudibranches/slides/Goniobranchus tasmaniensis2.html
  3. The Fantasea dome is 6", looks like it's a piece of a larger radius dome, but still a little on the small side. with APS-C you will probably need f11 for sharp corners with a 15mm equivalent rectilinear wide lens. Dome size and the required aperture scales with sensor size. For the same scene the depth of field is greater with a smaller sensor, so I can use f8 with my 7-14 (14-28 equivalent) lens, equivalent depth of field on an APS-C requires f11 and full frame needs f16. Big domes makes things easier as the radius of curvature of the virtual image is larger meaning that the image is further away and difference in distance between the corners and centre of the virtual image is less requiring less depth of field to cover. You might get better results at f8 than your UWL at f13 but to get the best out of the lens in the corners stopping down to f11 or so will certainly be a benefit.
  4. I'll have to look into it, the lens does not get a great deal of use - so shots where I could pick that up are few.
  5. Dome ports will be the same size regardless except of course for fisheye lenses. For rectilinear lenses the port size scales with sensor size and is related the depth of field needed to bring the corners into focus. If you look at DXO measurements, the Olympus EM-1 MkII is very close match for the D500 in noise, it loses a bit of dynamic range, but is surprisingly very close. This only applies to the EM-1 MkII, the other cameras in the Olympus range a bit further behind the the EM-1 II. That makes for a very compact setup, for the 7-14mm lens it uses a 180mm dome port and the lenses are all very compact. here's my EM-1 MkII in a Think Tank streetwalker hard drive backpack: In here is the housing with camera inside, 2x Z-240, OLy 12-40 and Pany 7-14, 60mm macro, 8mm Pany fisheye, the Zen 170mm dome for the 12-40 & 7-14, the Zen 100mm fisheye port and th60mm macro port, plus spare batteries, fibre optics etc. It will fit in all but the smallest overhead compartments or under the seat in front on any plane.
  6. The dome is the N85 II and it is about 115 mm from the outer surface of the dome to the outer surface of the housing. 5cm is the correct measurement for lens flange to where I estimate for the nodal point.
  7. Google photography pricing guide and you will get heaps of hits. Decide on a price point and try it out if it is snapped you probably priced too low. Allow time for editing and include things like image delivery format. Also you need to specify that the copyright remains with you and the terms you are licensing the use of the photos for. This can be anything from unrestricted to a very specific usage depending on client needs.
  8. Also depends on which housing system you are on and what size port you want. If you on Nauticam then there is an 8.5" (215mm) acrylic dome, if you want bigger like the 230 and 250mm domes for very wide lenses they seem to be mostly glass construction. Getting the big domes is what tends to make a difference for ultra wide (weitwinkel) lenses in the 11-16mm range - mostly in terns of corner quality. You will note in Nauticam's port charts one dome/extension is marked with an asterisk as being the optimum.
  9. did it with a tripod, levelled the clamp and head then moved it back and forth with a dovetail plate till the parallex shifts stopped, rotating it using the pan control. I have seen other references that say the point is where the aperture appears to be when looking from the front and it does appear to be in the same vicinity. I estimated it was between the top of the MF ring and the line on the lens hood. I may have completely stuffed it up but I recall I found a point where the parallex shift stopped, it was some time ago though.
  10. I expect the method used is more about expediency and finding the closest extension from the library of what is currently available in extension rings that will satisfy the majority of people who use the dome. Most people would have a hard time determining if the lens is placed correctly according to theory but would immediately notice vignetting. I checked my Pany 7-14 which I use in a Zen Type II dome - this is a partial dome (not 180° curve) with a radius of 110mm. that places the centre of curvature about 30mm behind the measured nodal point of the lens which is up near the front of the lens. A bit of geometry shows that extending the dome much further would cause vignetting. So in this case it a compromise to allow you to use a more compact dome with a larger radius of curvature than would be possible with a hemisphere dome.
  11. This is going to vary among dive centres, if you go to Lembeh in Indonesia, many of the dive centres offer two divers one guide as standard and they are used to people taking their time over images. Do your research on what type of guide to diver ratio is provided at different venues. Certainly in Indonesia there are many centres that have very good guide to diver ratios.
  12. The WWL-1 supports zoom through so it should work, assume they fit in the same port? Or if you have the Nauticam 45 macro port for the 30 then the lens comes right up to the glass so I don't see why it would not work, would be just like zooming to 30mm on the 14-42. Not that wide but still wider than the macro lens alone maybe a 70° field of view.
  13. Just because you have a camera you like to use on land does not mean that housing it is the best solution for taking images underwater. A lot of people like the Sony cameras and they certainly have good image quality. But going underwater is an expensive exercise and it gets more expensive as you go to larger sensors, particularly for wide angle where you need bigger domes to take advantage of all that resolution. You may or may not have the ultra wide (weitwinkel) angle and macro lenses needed for underwater shooting. Then there are the strobes which are pretty much essential to get the best images. You don't say what type of shooting you might like to do - tropical diving, diving in places like California etc.?? Are you dive certified or interested in snorkelling/freediving? All this makes a difference.
  14. I'm hosted on Lunarpages, I think mine is like $6 per month with more than enough capacity. unless you develop a big online presence it should be fine for most personal websites.
  15. I'm not sure that it really needs to be serviced that often. I dive in sandy areas all the time around home and on trips and have not serviced my nauticam housing yet after at least 100 dives. Just give it a good soaking after each dive. Also you want to use the right lubricant - your O-rings are probably butyl rubber unlike you main housing silicone o-rings and the lubricant required could well be different. I believe there is also a technique for including enough lube on each shaft - it's not like your houing where you use just enough to make it shiny.
  16. I only ever use the alcohol drops once I've done diving for the day, too often and your ears will get irritated.
  17. you would also probably want to get it neutral as well you don't want to be carrying something too light or heavy when snorkelling. I'd also suggest looking at the physical size of such housing to see what you will need to be pushing through the water. I would stay with the little Sony.
  18. Probably very little, fisheye and rectilinear optics are different and the fisheye has no trouble taking a 180deg curved virtual image and placing it on a flat sensor. - assuming that both have the entrance pupil placed at the centre of curvature of the dome. Big domes are used for rectilinear lenses as the radius of the virtual image is larger and you need don't need to stop down as much to bring both the corners and centre into focus. This is not as necessary for fisheye lenses
  19. Garuda gives you a free 23kg extra baggage allowance for scuba gear which is nice.
  20. That's the point I was making very little difference between m43 and APS-C with a reasonable gap to full frame and dynamic range is rarely needed, you are often stretching images for UW to bring up contrast. I am quite happy with my EM-1 II if I do the right things taking the shot, the results are excellent.
  21. Agree auto white balance. If it' s green it is also likely you need more flash output, the tint = 0 is likely the cause of the green cast. Auto white balance works very well with the EM-1 MkII. I use it with mine and Z-240 and the 4600 diffusers. The warmer diffusers are designed to overall warm the frame so when it is balanced back to neutral by auto white balance (it adds blue - shifts cooler) the water in the background becomes bluer. The camera will try to warm up the scene overall and if the light from the flash is not warm enough it will shift the water colour adding yellow and making a duller blue. You are are dealing with both ambient light and and flash light - ambient is 10000K plus possibly with a green cast and flash is 4600-5500K range. On the subject of flash output, i'm using about half power at f8 ISO250 for subjects in the rnage of 1/2 - 1m approximately. You can manually balance photos without enough strobe power but the reults are not as good. For me using Auto WB and enough flash power the images are 90% right as I open them in the raw converter. In green temperate waters you may still have a green cast to deal with.
  22. If you look at sensor performance the gap from the EM-1 MkII sensor to the D500 is very small in noise performance. There is a significant gap from there to a full frame. The only place the Nikon pulls ahead a little is dynamic range. There is also a reasonable gap from the GH-5 to EM-1 MkII in noise and dynamic range. This makes sense as the sensor performance comes from surface area to collect signal - light. A m43 is 225 mm2, APS-C 330-370 mm2 while a full frame is around 860 mm2. It provides a significant jump in light collecting area. You can fiddle around with ISO vs aperture a little for UW work, but there really is no substitute for chip surface area when it comes to astrophoto work and fast lenses really show their worth as there is so little light to work with.
  23. You might find it here: https://www.futureelectronics.com/c/interconnect/connectors-pcb--header-plug-wire-mount/products?q=%3Arelevance&text=&pageSize=100 or somewhere else on that website, but that would only get you a part number to search for unless you wanted to buy 100, then you need a crimper to attach to your cable.
  24. If you want to do larger than native resolution at 300 dpi (roughly 42 x 33 from a 20 MP m43 sensor) up-ressing if done right does work quite well if you start from the right file - well exposed not too noisy, sharply focused etc. I used to stress about being able to print big, but realistically it never happens at least for me, so I'm quite happy shooting m43. An A3 print is simple and quality great, A2 is certainly possible on most files. Full frame is great, mirrorless makes the bodies quite small but the lenses and domes are just as big as you would have with CaNikon DSLRs. The expense is also significantly greater I am using Nauticam housings and I could buy the housing and camera with change for the price of just the housing for a Canon DSLR - housing price seems to scale with body price. The noise performance of my Oly EM-1 MkII is a very close match for a Canon APS-C sensor and not far behind the SONY - but because the sensor is smaller you don't need to stop down so much and don't have to push into higher ISO except in some specific low light no-strobe scenarios. I have posted below my rig packed for travel in a carry-on size think tank streetwalker hard drive backpack. In there i have 60mm macro, 8mm fisheye, Oly 12-40 and 7-14 plus a 170mm dome, macro port and 100mm fisheye dome and two INOn Z-240s, there is space for spare batteries and accesories and laptop in a sleeve under the gear. The camera is in the housing. I've hauled around land based DSLR/super telephoto setups before and don't want to do that anymore, the weight and stress over carry-on allowances is not worth it.
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