Everything posted by bvanant
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A few years ago, I was a Medtronic tech fellow and we had a small ($15K) grant to do anything technical that wasn't about your day job. I decided to learn about batteries, specifically about rechargeable NiMH AA batteries. I talked to colleagues who design batteries for implantable devices as their day job and they helped me build a computer controlled battery tester. I bought every AA battery I could find, lots of cheap Chinese ones, eneloops (white and black) and a bunch of no-name ones from Ali Express. Name brand batteries that were tested at low discharge currents were in fact more is better i.e., if you put them on 0.05 A discharge rates the time to a specific voltage was proportional to the stated capacity. To test utility in a strobe, I took one of my Z240 strobes to the EE boys in the lab and they pulled out the charging circuit to emulate with my computer controller. Unfortunately they were unable to put it back together and keep it dry. In any case I tested all the batteries in pairs using the charging circuit and using a fast discharge and repeated til the battery reached the test voltage. What we found was that eneloop whites (2000 mAh) got the most flashes. Eneloop Pros were occasionally a bit more and occasionally a bit fewer flashes but were quite variable. Most of the Powerex 2700 batteries got 30% fewer flashes than the Eneloop 2000s. I was surprised but when I talked to my battery inventing colleagues they said "of course, we could have told you that" internal discharge is critical. I haven't run the tests lately (the instrument had a loud beep whenever a battery test completed and my wife got tired of 3AM beeps). Bill -
Cardiac Hill in Palos Verdes is a long long climb down (not so bad) with a handrail at the top, but going up with tanks and weights is for when I had a much different body. Like much of PV it is either really good or really bad. It is the reason that God made boats. Bill
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Linda is a trip. We did a 2 per night blackwater trip with her at NAD. Bill
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For sale is a pair of Fotocore GTM strobes, never been wet. I got these as part of a trade and realize that I really don't need more strobes sitting in a closet. They are very compact and powerful, with a beautiful light from circular flash tubes. Model: GTM Mode: 7 modes Guide number: 24 Flash tube: Circular flash tube Power: 120Ws Connection: Optical cable Illumination: 160°-110°(Reduction Ring) Battery pack: FOTOCORE battery (2 x 18650 lithium batteries) Battery pack power: 25.2 wh Flash Capacity: 800 flashes at full power, 5000 flashes at 1st mode Recycle time: 0.1s-1s Flash speed: continuous Unlimited flash sync with 10flashs/sec from first to third mode Power indicator: LCD displaying Color temperature: 5000K Waterproof Depth: 100m Focus/target light: 5W/ 500 lumens (center focus) Dimensions: 118*75mm Bluewater has them for $450, the Fotocore site has them for $450. Yours for $700 for the pair. Bill Shipped free in the US, outside the US you pay shipping. Bill
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There is a big push here in California to do "clear lens replacement" which is IOL surgery without cataracts. The big selling point is that you will never get cataracts (while true is a bit disingenuous since they take out the lens that could get cataracts). I just received today my new dive mask from Prescription Dive Masks in San Diego. Vision looks fine but will be out of the water for a couple more weeks so I won't get to test it soon. I got it from them at the Long Beach Scuba show, $400 which includes the mask. There was a company selling progressive lenses for masks, but they were like $700 and I am not sure that progressive masks make much sense. Bill
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Well the new Canon 100 macro for the R5/6 is amazing. Jeff Laity has some awesome nudibranch shots from local SoCal waters with it. Bill
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Don't tempt me. Working through the trip images now. BVA
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It works fine for what it is. If it had 1 stop more power it would be awesome. Someone asked did I get it for free? and the answer is no I paid for it at Divervision. I think if you are shooting full frame it might not be as useful but to make a really compact system (no arms and only one handle) it is a good answer. Bill
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I have long fascinated with shooting ring lights underwater starting with the Inon Quadflash, through the various Athena modifications to Sea and Sea strobe heads, continuing to the Saga fiber optic rings and now to the Weefine 3000. The Weefine 3000 is the latest version of the LED lights made by Kraken and Weefine. The Weefine 3000 CCW Weefine 3000 CCW Ring Light It's similar to the earlier 3000 lumen LED modules but has adjustable color temperature and a 3000-lumen burst (strobe) mode. It also has a super closeup mode that can shoot subjects as close as 25 mm (1 inch) from the strobe. It is powered by a protected, 26650, 5000 mAh Li battery. The battery can be charged via a built-in USB-C port. One very neat thing about the light is that it allows for a very small, compact system underwater. No arms necessary, just the camera/housing/port and a single fiber optic cable. The light is shown below on an AOI housing for the OM-1 camera. AOI housing for the OM-1 camera with the Weefine 3000 CCW Ring Light The ring light can attach to any port with a 67 mm thread and can be rotated for any angle once attached. One nice feature (or bug) is that when you are using the light in the strobe mode, it remains on at low power to act as a focus light. During the day it was not terribly necessary but worked fine at night, although you will also need some kind of dive light to find your way. My wife said it was very easy to find me in or small group, just look for the circular dive light. How well did it work? Better than I had anticipated. Years ago, I had the Kraken version of this light, and it was fine; this version with improved ergonomics (no multiple button pushes) worked great. Here is a nice little clown (Triopha catalinae) from a dive in local Southern California waters before the Raja/Triton Bay trip on the Wellenreng. This was shot at 1/160 sec, f/7.1, ISO 200 using the Olympus 30 macro lens on an OM-1 in an AOI housing. Certainly, enough light to illuminate the subject, I slightly reduced the shot exposure by 0.1 to increase the contrast a bit. For other local subjects, such as this anemone it also worked well. This one was shot at f/5.6, 1/160 sec and ISO 200. I shot with the light quite a bit on our trip to Raja/Triton Bay. Here is a nice little Goniobranchus coi, shot with the Panasonic 45 lens, f/6.3, 1/160 sec, ISO 400. I was very close; you can see the out of focus gills. I love Christmas tree worms, here is one from Triton Bay. Same lens, 1/250, f/7.1. Here is a crinoid shrimp, same settings. I shot a lot of tiny things, but also a bunch of anemone fish. Here is a Clarke in an orange anemone. f/14, 1/250, ISO 400. Overall, the light worked well for the things I was shooting, it of course is completely useless for anything more than 250 mm (10 inches) away. The color temperature is fine but shooting in raw lets me adjust as needed. A friend used the light as a video light for a TG7 with a 52 mm to 67 mm adapter and said that for most nudibranchs the light was much easier to use than independent lights on arms. I wish it had more power, a 6000-lumen burst mode for this type of light would be awesome, but the current version is adequate for micro 4/3 shooters and awesome for the smaller sensor cameras like the TG series. -
Is this what Alex reported? I thought he was saying he asked Nauticam for magnification just less than the SMC. Confused I am. Bill
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Well I tried it with every macro lens that I know about and it works in the sense that you get some more magnification but as for edge aberration improvement, it is not obvious to me. BVA
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I just shot the MFO against some ISO targets. As far as I can tell for micro 4/3 (30 macro Oly, 30 macro Pany, 45 macro, 60 macro and 90 macro, there is no obvious increase in edge quality. Perhaps it has great use only in FF cameras. I talked to the Backscatter guys at the Long Beach scuba show and they said of course it is only for FF. I wish they told me that BEFORE I paid them for it. Bill
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A lot depends on what you want to do with the images. If you are wanting to make 3 ft by 6 ft prints then more pixels be more better. For 16x20 inch prints, or smaller or for sharing online then u4/3 gets you more than enough to work with. Video capabilities are beyond my understanding but both Olympus and Panasonic shoot with good enough resolution unless your unlimited budget includes an imax theater in your garage. We just finished the scuba show in Long Beach where OCUPS had a booth. I did all the prints for the booth at 12 x 16 inches on metallic paper. We had shots from Z9, R5, D500 micro 4/3 TG7 and even some iPhone shots. Hard to tell which cameras made which pics. Bill
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It is always interesting to ask the manufacturer but remember they were the ones that glued it on unsuccessfully 😃 Bill
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I agree with E6000 or I have used this for gluing all sorts of things to housings and other toys. Bill
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I have shot it with the Olympus 30, 45 (Leica), 60 and 90 macro lenses on an OM-1. The focus speed for the 45 was improved, the other lenses not so much, maybe a little. I have struggled to demonstrate the improvement in IQ away from the center of the frame with any of these lenses. Maybe the micro 4/3 system is less bothered by flat port aberrations than full frame systems. The small increase in magnification is clear but for me at least shooting really small stuff, not so useful. Bill
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I really like the idea of a variable diaphragm but am too busy to try to make one myself. Cheers BVA
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Long ago the DAN camera insurance was inexpensive and covered all kinds of loss. Every time a new camera came out there were a ton of "my camera/housing fell overboard and was lost" claims. After a couple of years of this camera loss was no longer covered. The DAN insurance used to let you decide how much to cover an item for, but I haven't looked for quite a while. Bill
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Depends a lot on your home insurance. Many folks have reported that their homeowner's insurance premiums have increased after they made a dive housing claim. We live in Los Angeles and it our homeowner's rates went up since the fires. We self insure by creating a small ($15K) investment account that we keep mostly liquid. Over the last 10 years and 1500+ dives with no major user errors, we are quite a bit ahead of the game but also recognize that we are quite lucky. Bill
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Will you be selling them? Bill
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My take is that strobe EV control is aspirational, not real. But the difference as noted is tiny. On some cameras you can set the EV gaps. Bill
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I love "egowank" will have to steal it from you. Bill
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"I have a friend who had tri-focals done a while back, I believe he had them changed to mono-focals, apparently a common side effect is visual disturbances at night, some people get used to them and some don't. There is also an enhanced depth of field option which keeps a wider range in focus. " I am quite skeptical of this. IOLs can be removed and replaced, but this is both tricky and quite rare. My opthalmologist says that while he does 600 to 700 implants a year he does one replacement every 7-8 years and then only if the original IOL has moved. I just had both eyes done, great distance vision, sucky reading. One interesting observation, I had bad astigmatism and I still have some but it has rotated 90 degrees. Cheers Bill
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Here is the last set (before the pool controlled experiment). These are with the OLY 90 macro lens (in 1:1 mode). In general the focus speed seems about the same, but it already was super speedy. These Tenelia sibogae are from Triton Bay. I THINK I can see a very slight difference but it really is hard to tell. Bill
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Love the pompano. Guides do what they think will get them tips. If at the beginning of a trip you talk to the guides and say "every time you manipulate a subject your tip will go DOWN" you won't see bad behavior much. Years ago there was a Michael Aw (I think) photo of an octopus in a sunball. For years afterwards, divers showed the pic to the guide and said "I want that". Guides regularly took occtopus up to the surface for the shot. As long as you tell your guide before the dive what behavior you expect, I think you will get what you want, as long as the guide is for a small group. Bill
