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Interceptor121

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Everything posted by Interceptor121

  1. I have been recently testing ProRes RAW on the Panasonic range. My conclusion is that is not worth it. The primary issue is that the camera only works with a set white balance in RAW. Once you need to do that then there is no longer a benefit in raw in fact the workflow is more time consuming. Other aspects lack of lens corrections etc. How does canon manage those?
  2. So low light matters And the - ev of both those cameras is -3 ev Which means they are very very close So the extrapolation of this metric out of specs in this case is a valid proxy Tracking however does need specific testing Sent from my iPhone using Tapatalk
  3. I did volunteer at the time however the subject becomes quickly very technical and there is no substitute to a good story Macro videos are especially challenging if there are no behaviours they can become a slide show of critter and frankly a set of pictures would be better Video is very hard even on land it’s 2 months that am shooting a project i have terabytes of data and still lacking some scenes! Sent from my iPhone using Tapatalk
  4. Not everybody lives 5’ from blue heron bridge Understanding how things work helps maximising your chances of success especially now that all pools are closed and in essence there is no diving other than your bathtub Sure going and testing is the right thing to do but to make dismissive statements spend more time in the water denotes a lack of understanding and empathy for majority of people that do not have the opportunities that you have and don’t do this as their day job Sorry that was really poor Sent from my iPhone using Tapatalk
  5. Yes but there is also the fact that people that like forum are older and driving traffic through your channel generates some business in a way The videos of BTM are a good example of well executed marketing
  6. There was an interesting survey on dpreview about photos and videos. Surprisingly although people like to take videos with their phones there were many people complaining about the fact the cameras are getting expensive because of video features (!) The reality is that photos are much easier (I know am going to get a beating here) the process of taking a photo, editing and posting can be made very efficient Video is a beast you need still pretty strong hardware but more than anything else you need to tell some story if this is not just for your personal consumption. On the field video is harder because you shoot while moving, you need to manage exposure in thousands of frames not one. So ultimately many people do not undertake the journey at all. Years ago I forecasted that with faster connections video would have become more popular but in reality this has only benefitted Instagram and their 1080x608 videos and vlogging of people doing some form of affiliate business We also need to account that many of the photographers members of a camera club or going for underwater trips are over 60s and they do not understand video at all This does not excuse that wet pixel should make more of an effort on this in my opinion even if this mean talking about gopro
  7. A guy I know has one but it is in Italy?
  8. I have recently invested in a Ninja V to start using it with ProRes RAW on my Panasonic S5 Surprisingly for me the product is buggy and has a lot of inconsistencies. So I thought of writing a few tips here 1. Zebra are generally off. They can be off 5% to 10% and in some cases cannot be set for clipping. In general they are over the real value (you can check on the waveform Zebra set to 100% means waveform at 95%...) 2. False color does not scale it is always on the same range 0 to 109 which means if you shoot a standard video signal or log it never ever shows red unlike other monitors like SmallHD. The solution is to use your own false colour LUT or to use a VLOG to Rec709 LUT and then use false colour on that 3. There are issues with prores as this format only allows legal range but Ninja writes a full signal. Lately a legalise option has been supplied for users of all products except DaVinci that can be set to ignore the file flags. There is some level of deterioration with this option but is minimal 4. The monitoring of HDR signals in the Atom HDR is an utter mess. The monitor is just a rec709 10.5 stop screen it does not support display of wide color gamut so when you try and monitor in PQpr HLG it scales the signal and the screen becomes so dark you cannot see a thing. It is better to use your own LUT (see point 2 above) and ignore those settings. I hope this helps prospective and current users of this otherwise pretty decent product
  9. That would be generally possible but it will very much depend on the specific lens. The Canon EF macro lenses focus fast generally they are not sluggish so this is something to consider for sure Personally I would not invest in a Sony system for full frame for a variety of reasons. The Canon RF system instead looks very promising
  10. Yes Olympus specs are for 1.2 prime lens at not very long end so when you look at 2.8 you are at the -4.5 Ev of anybody else in single AF Tracking uses motion vector estimation https://en.wikipedia.org/wiki/Motion_estimation this requires processing of entire frames not just a contrast point which in turns means the camera needs to have full video frames processed to analyse to see if it has lost the plot or not. This in turn means the level of light required are increased. In the mix goes also how fast the lens is to achieve focus. Some lenses like the Olympus 60mm are pretty bad and they have a lot of breathing when you focus. So if you focus it first and then stay around that area it works much better. But the performance compared to a standard zoom lens even at the same aperture is just terrible The ability of the camera to work at low level of illumination together with the ability of the lens to focus quickly determine how effective it is underwater. So going back to the op question assuming the test is performed with lenses of similar aperture (generally this is 2.8 for full frame not less or they may not focus at all) a camera with a rating of -6 Ev will work better than one with -3 Ev which is where this started as a starting point. Then you need to overlay focus speed and accuracy that has also to do with the lens. For tracking there is an additional dimension which is the quality of the motion vector estimation which depends on the processing quality and power of the camera. Sony for example has very good record of tracking in daylight but at the same time a pretty bad reputation of not focussing at all in low light and being slow with macro lenses. If you add a focus light in the mix (obviously this is important because a lot of macro is inside crannies where there is no light and you are much lower than your desk) almost all cameras can focus (eventually) at the focus speed of the system. I would be a bit calm before saying that underwater there is plenty of light there is not. A nudibranch on a rock sitting flat with light hitting it is not the same as trying to shoot a seahorse on a fan at an angle where light is not reflecting. So if I had to look at performance of a lens for macro I look at the following dimensions 1. Camera ability to focus in low light (most cameras are rated -4 Ev and lower and I would say away from anything that says -3 or -2 Ev) 2. Lens time to scan for focus. Before you can even think of engaging tracking you need to pre-focus and that first operation is critical so you can continue I do not look at how good the camera is at motion estimation and this is not a published stat so there is no way to read something and see if this camera will be better than another at tracking Going back to @Architeuthis question. I use the MC21 adapter and metabones like he does. With adapted lenses only Single AF works reliably so tracking is not available. The two criteria above hold. The Sony camera rating of -3 Ev is not convincing for me Among Canon R5, R6 and R the rating is respectively -6, -6.5, -6 but obviously the R6 has a lower megapixel count Having discounted adapted lens if you wanted CAF or tracking you are left with the Canon 85 mm f/2 which is not known to be particularly fast. The reality is that DSLR in this area is still way ahead when it comes to focus speed as the lenses focus really fast. It would be worth to find someone that has tested the Canon RF 85 AND the Sony 90mm to see in real life how those work I would avoid any adapted lens for macro. Perhaps the Sony lens is better than canon and makes up for the camera being less able or you dive with a focus light and you are done with it. I would not invest on a system if there are no native lenses as adapted lenses are always a compromise you can take for wide angle but not for macro in my experience. Hopefully this last post helps Wolfgang making up his mind
  11. Yes that’s what I wrote the camera is focussing with lens wide open but increasing gain ISO increases noise which in turn makes the camera fail sooner when you engage tracking that uses live view not a single AF read I have no issues with my camera focus most of the times the reason I use manual focus is to make sure the macro lens is at maximum magnification If you use autofocus you don’t know if you got close enough until it fails For me the autofocus story is mostly a hype but if someone wanted to compare you need to look at the combination of camera lens and situation Sent from my iPhone using Tapatalk
  12. 30 lux is not low light level and is around 4 EV in fact If the claims of -6 ev of olympus were true it would focus at 0.04 lux This is single AF In tracking AF the value reported drops because the camera is analysing frames and can only do that processing video So the tracking drops much sooner than your example cameras resort to tricks to compensate increasing gain but this eventually comes to an end So the performance of tracking and single or continuous AF is not the same At f2.8 1/30 (refresh used to interpolate video frames) you would need 588 lux for it to work at ISO 100 the camera increase gain so that it can see it but this increases noise and makes the tracking likely to fail This is way in low light cameras only focus in single AF Try it yourself with C-AF-tracking (which misses a lot also in bright light) Sent from my iPhone using Tapatalk
  13. They use the same camera for all the lenses test so that when they say it is slow it means it is slower compared to other sony mount So this is useful to assess lenses on a format. In our case the op wants to compare across formats this is much more difficult to do and there is no reference data handy
  14. Phil Rudin makes a good point as usual. Lenses motor and precision are important The sigma 105mm produces very nice images but is very slow https://www.lenstip.com/lenses_reviews.html has most lens reviews for emount and other mounts and is usually very reliable
  15. read it again. Even with your lens fully open at f2.8 the EV of the scene is 11 which corresponds to 2200 lux this is more that you get on a surgeon table. Your camera has to focus before your strobes fire. So there is not plenty of light if there was focus lights would not be needed would they? I realise most people do not actually understand why cameras have issues underwater by reading the answers I get in this post Anyway as I actually don't need or use tracking either on land or underwater I leave it to you the experts to wonder why your cameras do not focus!
  16. Tracking works on the assumption that the frame is still and the object moves. It is called motion prediction. If the frame moves and as result the subject moves tracking fails you can see this yourself on land swaying the camera while you point at something. Some systems like Nikon 3D tracking (which works differently from mirrorless tracking) are effective in the 'swaying' mode. Is almost the only one the others all fail miserably
  17. Because you are using the camera at negative exposure numbers (most cameras AF refuses to work when the exposure meter is below -3 unless you are in manual focus) you are effectively in low light. The example that I provided is based already on wide aperture and goes to show that even at f/2.8 1/250 a typical macro shot the camera is expecting a level of brightness much higher of what it gets underwater. So the ability to focus in low light in fact matters because you are not exposing for middle grey as you use your flash to provide light This may be difficult to understand but this is the reason why cameras fail to focus underwater. If all was bright you may occasionally focus on something that is not what you wanted but rest assured the camera will focus. Try some garden macro and see it for yourself. With regards to tracking as a proxy of the diver moving this is resolved by the diver NOT moving not by the camera tracking. I know some people rely on those features but those are designed for the camera to be fixed and the subject to be moving as they are based on motion prediction so something has to be still relative to the other. The Olympus tracking Wolfgang mentions on land on a bright scene is mediocre at best. I would really like to see the hit rate of this shots. Nobody shooting a bird uses tracking today Cameras are moving in the direction of subject detection (i.e. identifying what is the subject in the frame) to then focus on it. This method has got the highest success rate. Unfortunately fish are not an animal the camera will detect The traditional tracking with motion vector on a mirrorless camera requires analysis of the frame which means it is operating exactly like in video mode. In the above f/2.8 example assuming a frame rate of 30 fps we are looking still at 9 EV which is still very very bright and nowhere near an underwater situation UNLESS you have a focus light. A modest focus light with a narrow beam of 60 degrees and 180 lumens at 1 foot provides 2292 Lux which is 9.8 Ev at that point the camera will be very happy to focus track and do whatever it needs to do Once light is provided almost any camera on the market can do the tracking job or any continuous autofocus A comparison like the op requested does not exist and it will not exist until someone goes in a pool and scientifically tries all those camera under constant illumination. Nobody does those things in the world of underwater photography so we are here to discuss things at libitum However who understands the mechanics of a camera usually takes the right decision in less time and ends up with all the shots in focus.
  18. It is in the port chart so I would say yes all lenses that are tiny in size and have a nodal point quite recessed can work When I said full frame I meant cameras with N120 port which Sony is not part of as they have N100 The WWL-1 however is not a fisheye and is just an alternative to WACP for those who want something like that
  19. Get closer. Those distances are ok for video perhaps but photos will have no contrast no matter the camera Autofocus is not an issue with the WWL-1 or any wet lens in fact I focus at the beginning of the dive practically
  20. Macro photography is low light by definition as you use small aperture fast shutter and low ISO If you put a focus light in the mix any camera can focus easily all the ideas you need tracking for macro etc for me are more wishful thinking and a proxy for the diver not the subject moving
  21. No it doesn’t work that way the lowest ev is a negative value and the ev are always added. So the range is 11ev + the range so this results in an offset. Say it was 20 to -4 it becomes 31 to 7 ev. Other than the math this is a CIPA test on single AF which maybe is not what you use anyway The negative value is a good proxy for that however performance in continuous mode falls apart much sooner. Cameras employ then other tricks like reducing the shutter speed and therefore the frame rate of your evf to try and focus this generally kills entirely the continuous autofocus that needs high refresh rates All considered the negative ev mentioned remains your only point of reference In general all mirrorless camera switch to contrast detect in low light and the different performance shows how well or how bad they cope in those conditions that are typically different from the normal operating conditions The only real way to see if does or not apply to your use case is a test obviously Sent from my iPhone using Tapatalk
  22. When you look at how focus systems are defined you need to understand how the camera achieves focus Most cameras achieve focus with the lens wide open and the close the aperture when they need to shoot. This means that if you are shooting macro you are effectively at f/2.8 with typically a fast shutter speed say 1/250. This is a scene that has an exposure value of 11 EV at ISO 100 or 5120 lux in essence a sunny day. Your camera will typically have a -Ev rating for single AF (forget about tracking) which is usually something like -4.5 Ev In our case 11-4.5=6.5 the camera will refuse to focus at less than 226 lux which is not that dark after all. Increasing gain (ISO) does not change the camera ability to focus but helps you seeing the LCD and focus manually Looking at your examples Sony A7R4 EV -3 Canon R5 Ev -6 The canon R5 has 3 stops benefit For reference Nikon D500 -4 EV Panasonic S5 -6 EV Nikon Z7II -4 EV So Canon and Panasonic have an edge on Nikon/Sony probably due to the different nature of the autofocus system. Adapted lenses do not perform as well as native
  23. For those who did not understand my previous post what I am saying is that the advice given in the video to shoot wide angle between ISO 100 and 640 will be appropriate for the camera @Alex_Mustard shoots but not on another one that has a different design Nikon cameras use Sony sensor but are designed in a completely different way from Sony or Panasonic cameras that use the same sensor family not only that some sensors are front illuminated and some are back illuminated and those behave differently Finally cameras do not meter the same way so if you take brand A and say -1/3 works well as the camera cannot meter perfectly in water you may find another one where it needs +1/3 Know your camera in detail in essence is the motto
  24. ISO is one of the most misunderstood concepts of digital photography and that is because a camera has only one sensor and therefore only one film. You can't go and change the film you can only proxy that with gain which is what ISO maps to You can't generalise concepts due to the different way sensors are constructed so one camera may be totally fine at 2500 and one be rubbish. Also some cameras are ISO invariant and some are not at all and this influences how you should shoot. Only one thing is for sure an image with too low ISO that is too dark on broad area is worse than one with a small clipped highlight in my opinion If you want to maximised performance in your camera I suggest you study not only DR charts but also input referred noise charts
  25. If it is polycarbonate it cannot be polished if it is hard coated unless you remove the coat altogether It is always a trade off hard coated scratch less but when they do they cannot be repaired. Uncoated scratch less and you are there repairing them a lot on the field but once you are used to is it is all good
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