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Tom_Kline

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Posts posted by Tom_Kline


  1. I suspect part of the story is in how well parabolic optics are used in the strobe. That is, actual position of the light source inside the reflector.  See the diagram at the bottom of this page.

    https://www.edmundoptics.in/f/precision-parabolic-reflectors/13727/T

    The now over 50 year old Subsea strobes did this rather well with a flash tube that had a corkscrew shape but could be focused via a knob on the outside of the strobe (so could work under water).


  2. In the photo above I used the aiming light built in the Retra strobe. This was to keep the light within a narrow circle in front of the camera lens. It was very shallow here 10-15 cm deep so a very small volume as well. More recently I have been using two strobes because they are to the sides in a rocky habitat I used my old Inon 220 strobes which I would not mind so much if they got scratched. For this setup I had a very small Supe aka Scuba Lamp light similar to the one Alex had in one of the Wetpixel vids of the last year or so. It is model PV10S which I think is out of production. I have been able to use it for 2.5 hours in 5C (40F) water. Mike is using much larger lights - see interviews with him.


  3. Big domes are impossible where it is too shallow for them. In this stream I have struggled to use micro domes and other small ports. This year I used the Nauticam EMWL with the 100 degree objective. Even so it was challenge to submerge the port housing the 105mm lens.

    The location is in the upper inter-tidal. Seawater reaches the base of the sedges growing at the edge at the higher of the two high tides that occur each day during spring tides. These are Pink Salmon, now an invasive species in northern Europe. They have a two-year life cycle so are the "rabbits" of the Salmonidae. This location is about 2km from where I am sitting right now

    IMG_0339.jpg

    IMG_0351.jpg

    IMG_0420.jpg


  4. The score is what one gets from the PowerX Analyzer (no point in using the mili prefix IMHO). It should be the actual capacity but the max it can deliver in current is unknown. I was using the Inons at very low settings -4 and -4.5 so the batteries were not being stressed for recycling but I did shoot a large number of pix. Strobe setting varied as well as lens aperture, either f/18 or f/20, using the EMWL. Still dialing this in for my conditions - ambient light is going down. Mainly was trying to avoid blown highlights as salmon have white parts as well as reflective scales.


  5. I had one eneloop pro die last weekend. It was one of 8 I have been using in two Inon 220s this summer. It registered as HIGH when I put it in my battery analyzer (discussed here before). The other 7 were OK i.e. not HIGH when I analyzed them. With our continuing deluge (so no chance of photography as my local lake is about 1 meter above normal) I decided to put them on the analyzer today - 3 of the remaining 7 were HIGH! I had three good shoots this week (consecutive days with sunshine and just a few clouds) so they did get some heavy use (> 2000 shots/day). As they were fully charged I put them in a three-cell Inon light and the light works. So they are not fully dead but likely not reliable enough for strobes. These pros are dated 2018 so past the 3-year limit.

    I have 8 more pros. One group of 4 scored 2.2+ Ah while the other 4 scored 2.3+ Ah (about a 50 mAh range for each group) this week (analyzed them after the first one went HIGH). These have not been used for about 2 years so they may not go down as fast if not used. I may switch to them if more of the remaining 4 score HIGH. All 16 were bought at the same time to use with my two original Retras per Retra's recommendation.


  6. 47 minutes ago, Phil Rudin said:

     

    Again these tests from Nauticam are all shown in the article by Alex in back issue #99 at UWPMAG.com. This is a free PDF download that everyone WACP-curious should read.

     

    I am curious to see similar graphs on the EMWL lenses. Any out there?


  7. I guess another way of looking at this question is asking what one's criteria are for rejecting or keeping images. I will admit that I do use technical criteria. In the case of my salmon pictures, which quite numerous, I do reject many that are technically proficient and have good composition. I therefore have to have other criteria. One that I use is if I cannot think up a caption other than naming the species or something so simplistic that applies to many of my other salmon shots just as well.  I do have pix on my website that have just the species as their caption. I am, however, more critical of my salmon shots. I have tossed many simply because they are boring. On the flip side; if the pic shows an interesting behavior I may keep it even if not technically perfect.

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  8. 9 minutes ago, TimG said:

    I'm not sure higher education makes anyone more discerning in terms of photographs (or many other aspects of life come to think of it!) or any other form of art. Knowledgable maybe but this doesn't necessarily translate into artistic appreciation - or lack of it.

     

    This depends on how many graphs, data tables, etc. one has closely examined looking for patterns, faults, etc. One needs to be analytical. This is a question recommenders are asked of potential graduate students. By the time one has a Ph.D., at least in a science discipline, one should have had a some experience!  As well one is trained to be critical, e.g., to do peer review, especially of one's own work.


  9. Over the decades I have observed people reacting to photographs. These observations have included positive remarks of photographs (e.g., photo is great) that I would have immediately rejected if it had been mine, even by well-educated people, e.g., those with Ph.D. degrees (and thus should be a bit more critical). I surmise from this that technical execution far less important than the subject matter. I suspect that non-photographers may not even notice the soft corners of many wide-angle underwater shots and other technical issues.


  10. Z9 3D tracking mode works differently than having the camera find the subject within a designated area (this area is quite variable and is selected separately from detection mode). Doing vids, 3D might be preferred if you are able to see your subject at the start. I tend to have the camera find the subject for me using one of the rectangles (from FW 2.0 on)  but pick where in the frame to pick from. For example I picked a narrow horizon box so the AF picked a bird from the row of birds that I selected - keeping the frame over the row if I recomposed. Birds were entering and departing by flight from each row (resting shorebirds). Worked well for that.


  11. Good points. I would be concerned if there was aliasing between the AF and the raster image of the video. For example if there is a moire pattern, how would the eye detect algorithm deal with that?

    There is a moire pattern when shooting images of my high rez (6K) computer monitor which I do when following instructions on a pdf manual and playing with the settings - great to do on rainy days.


  12. What happens if you find that one of the three is best for video, e.g., the Canon, another of the three is best for stills, e.g., the Nikon, while the third one is best for swimming  with (because it is the smallest and should have the smallest housing), e.g., the Sony? Be aware that Nikon just updated the FW for the Z9 yesterday to improve the eye AF. Not using FW 2.1 would invalidate your conclusions regarding AF.

    I also suspect that using a video image to test AF, tracking, etc.will have issues due to nature of the electronic image. It might be better to go to a public aquarium that has a huge tank and shoot there especially if the room is darkened. Keep in mind you will be shooting through a flat port so best try to be perpendicular. It might need three trips doing one camera at a time unless you like carrying that much around with you.

    • Haha 1

  13. I found a shot of the scuba set up from my trip to Kauai in 2019. This was my test to make sure both strobes were working prior to a night dive. I left for the dive shop with the float -arm attached since I used short arms for the macro shooting (was able to fit in bag). Bathroom mirror in condo. Also a record that I used a dome port with the 60 Micro Nikkor for the dive! Dive computer strap can be seen. Note that the lights are flopped down (for transport) on YS segments that I forgot to mention above. Inons are not the ball type light (per Adam).The 5 degree light is the wider one! One big advantage of these lights is that the on-off switch is on the rear facing me. The inked in T and W are my attempts to idiot-proof the zoom knob. Also written on the top surface of the housing. Also on my other Seacams. I also have "zoom?" written on the top of the VF bump. This is because I do a lot of remote photography that does not involve using a viewfinder. Yes, the zoom has not been correctly set a few times! The ring rotates when mounting the lens into housing so gets re-set.

    _D3Y1394-2.jpg


  14. 10 hours ago, adamhanlon said:

    Compact size 
    Probably powered by a single 18650 cell, although AA combinations would be fine too.
    Ball mount

     

    I have been using a light that meets these three requirements successfully for my freshwater-blackwater photography lately. Very light (in more ways than one) which is important for this application. I tired a single Inon "pencil light" (3 AAs in a line) but the AF struggled. I am finding that it takes quite a few hours to charge up the single battery. As well one has to push the button a lot to toggle through off, on1, on2, SOS, and back to off. on1 and on2 are two brightness settings. The attached pix provide a better explanation than words (shot with an Ipad mini).

    I am using the larger diameter Inons for scuba (groups of 3 AAs in a plastic holder). There are bunch of models with longish names. One has a 5 degree beam and the other is wide. The 5 degree light uses 3 AAs whereas the wide one uses 6 in two holders like used in the other one (but just one holder in it). It has a 3100 in the name. There is another model with 1300 in the same place. The rest of the names are identical. Inon sent the 3100 to the US dealer instead of the 1300 (what I had ordered) which has an identical body to the 5 degree light but not as versatile and powerful. With 6 cells it can go through several dives no problem. The 5 degree light is useful for spotting things during the day at modest depths in HI, e.g., 25m, where there is little color. The 3100 etc model is used for focusing. Lots of overhangs and lava tubes so needed on almost all HI dives. I have the two lights attached to a float-arm via a 3-way clamp. The other end of the float-arm attaches to the pole-cam ball in the center of my housings. I remove the two lights with float-arm as a unit for packing the housing on and off the boat (day tripper mode in HI). This makes it possible to close the bag! I mount a dive computer on the float-arm.

    IMG_0030.jpeg

    IMG_0092.jpeg

    IMG_0078.jpeg

    IMG_0101.jpeg


  15. On 6/22/2022 at 12:20 AM, makar0n said:

    The one problem we average Joe's have is articulating those rationales. since we do not have access to multiple bodies nor, living in cold, dark places, buddies with housings, to test things in the wet way...sometimes we get carried out with the "ooooo shiny shiny new toys" rationale, which then requires numbers therapy ;)

    Yup - have to spend quite a bit of time on line. Zero people near to me with the same interests as well. No dive shops. No camera stores....

    Nonetheless I have had to make the instant decision. This was the case when I ordered the Z6 - within the hour of its introduction. The live stream from Tokyo was at a good time for Alaska - in the evening of the previous day here. I had been in the market for a "sidekick" to my FF housed Nikons which I wanted to take on trips due to the Nikonos lenses (rather than the Canons that I had use up to then and had the 7D2 as my sidekick). I was challenged to decide between the 7200, 7500 and 500 as they each had pros and cons. With the Z6 there was no hesitation.


  16. 9 hours ago, oneyellowtang said:

    Yeah... no.

    One example... side by side shooting in dark conditions (A7R4 and D850) - D850 performed better (in a hold of a wreck). I've actually seen some Sony shooters turn off their Live View in some dark conditions because it absolutely screws up your night vision...

    I will have to agree with I 121, it seems more like an issue of user error. I do my share of night photography as well with my main subject being the aurora. The main trick is getting a good infinity focus which can be difficult with an SLR - focusing on stars if the moon cannot be seen (manual focus). The first time I used live view was for this task - it was with the Canon 7D2. Subject was a comet. Lens was an 85mm f/1.4 to be used at f/1.4. One night it was actually clear so that I could see it. The next night as well and that was it for the entire comet period due to being near the ocean (foggy at night when clear or otherwise overcast). My cometography was not planned in advance. It was a quick decision. I grabbed the camera, lens, and tripod and headed out the door (flashlight in pocket). I did not even know how to turn on live view!! So I had to go back in a few times to consult the instruction manual that I opened and read on my computer screen. I also grabbed a Lupe. In general I have found that live view on DSLRs works better for manual focusing than the OVF. One needs to use a lupe, however (keep in mind I am old and cannot focus as close as when younger).

    And that has improved quite a bit with recent cameras due to improved screens as well EVF. I use the EVF (at 200% on my Zs) when manually focusing. If the EVF is not practical I will use the rear rear screen. For example, I have done a couple of night shoots with the 8-15 lens at 8mm with the camera pointed straight up with the screen flipped out (ended up in a vertical orientation). Besides focusing, I used the screen for composition (e.g., minimizing street lights) and for chimping (for exposure). I have not used the Z9 at night because it is the non-dark time of year (just twilight after sunset now).

    No EVF experience night diving but plenty of DSLR screen usage. It is important to lower the screen brightness! I mainly use the screen to check exposure and have had auto-chipping off (but am considering having it on the next time). The reflectivity of subjects during blackwater photography varies by multiple stops so it is rather important to keep checking. I have blown a few shots such as when a fish quickly entered the scene. As well the gut contents, especially of comb jellies (carnivores), can be quite reflective. It is important as well to return the screen brightness back to normal after a night dive - I have forgotten once. It may have had something to do with getting back to the hotel after midnight and then scrambling to charge batteries and clean up and set up gear for the next day.

    I do not use LV for diving (DSRs) at night because of the exposure simulation issue. I do not think it can be disabled on my D4S. I did not even try to turn it on with most of my Canons (easy-peasy on the D4 series). However I might if the view brightness could be controlled independently (of exposure) and fixed which is the case now with mirrorless. According to Thom Hogan the Z9 AF depends on “exposure” so this might be an issue for night diving at small apertures and using strobes. We do use focusing lights but are they good enough?


  17. 28 minutes ago, TimG said:

    Fair points, Tom. You’ve got very specialist needs which FF meets. That was a point I made - but for the average Joe, not so much. 

    Yes!!!

    I think examples are needed! Many seem to want to upgrade without articulating a good rationale or two, etc. The average Joe might do well with something even less than what the OP has. I see a lot of Sealife and Go Pros when diving in Hawaii. The only local (to me) that has given an UW presentation used a Sony 100 model with wet lenses - the results wowed most people in the audience although the pix were not all that sharp. The projector may have been dodgy as well (I used a different venue when called).


  18. 13 minutes ago, TimG said:

    Wow, some fabulous images. Problem is, Tom, they're all not underwater :man_in_love:

    I really would like a Z9 though. And Land Rover Defender (new one). And a Ferrari. A megayacht would be kinda cool too.

    Yes, there is a need to extrapolate from non-underwater users! The Z9 is not all that bad in cost. The housings, something else....

    What will be interesting is to see which aspects of the tech in the Z9 end up in the next gen cameras. Nikon has already indicated that this will be the case. Possibly one of these will be better for warm water UWP (smaller and less expensive a housing). However in the post-covid world we may have to get used to much higher prices. :<<


  19. 1 minute ago, TimG said:

    The Voice of Reason: saving one photographer at a time..... :crazy:

    !!!!

    IQ alone is insufficient rationale for up-sizing one's sensor size IMHO. One needs to be rather specific such as a desire to make really large prints that have been unsatisfactory with current gear.

    I use FF. My main bodies are the Nikon D4S and Canon IDX that are used mostly in auto ISO mode with max ISO set, respectively, at 16000 and 12800 for available light shooting (spring to very early autumn). These cameras have resolution in the same ballpark as micro four thirds cameras but have about a 3-stop high ISO edge. With direct sunlight I typically get from ISO 5000 to my max (when a cloud blocks the sun). Use mainly fisheye lenses (so no real small lens apertures except with micro-dome). Need short exposures due to fish movement. Shallow water but at 60.5 degrees north latitude. The big batteries also help a lot because the mean water temp in my streams is 5C (actually measured by a graduate student).


  20. Adam I gather you did not use the new style cable adapters. (???) It looks like an FO in the cover shot for the vid. Since I already have two sets of Retra strobes - the original and Pro models - I have been reluctant to buy a third set!! For me the main advantage of the X models is the new style cable adapter (call it model 3) which I am compelled to use since I have Seacam housings which do not have dedicated FO ports (the brand's main weakness). I am thus curious about their use.

    While the improved version of the non-attachable cable adapter (model 2) works, there is a lot of lose cabling as well as dealing with the lose heavyish adapter. The supplied velcro strap is highly unsatisfactory IMHO (I could use more colorful language!). The only advantage is the ability to swap out FO cables and even not attach them until settled in under water. I have been attaching them just before deploying a pole-rig for recent night work (until spring started).

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