39mp underwater

Hey, Troy. I heard last year at DEMA that Patima (Korean housing company) was planning on selling digital MF housings made out of titanium. I don't know if they ended up pursuing that project, but it would be pretty cool.

Titanium is a real Hillary! to work with...

On the other hand, my cousin was a machinist for an engineered ceramic company (up-armored Humvee panels, precision jet engine parts, etc...). Making a housing out of ceramic would be a breeze: Simply build a pattern, make the investment, cast the material in the investment, fire it, and then shave off what little is needed to get the tolerances down to +/- .001 (or even better).

Making the pattern is a snap with wax, using lasers fed by CAD/CAM. In fact, hearing aid earmolds are now made that way: The dispenser simply takes the client's ear impression with silicone, puts the impression into a small box next to his keyboard where lasers measure it. Then, the digital "impression" is sent to the lab where a wax copy of the impression is made (after the technician edits it & touches it up). Then, this impression is used to make the investment (the same way as if the impression had been mailed into the lab). Then, the earmold or shell is poured into the investment.

It would be a no-brainer to simply use a larger measuring device and scale it up: Just drop the new Nikon D3x into the box, scan it in, edit it accordingly; and make an investment to cast the ceramic. Then, do the final drilling & machining to get the tolerances just so...

No big shake, as Pee Wee Herman would say...

I'm not sure what the advantage of Titanium over Aluminum is for this application besides nerd appeal. Aluminum is half the weight, cheaper to buy and work, and is certainly strong enough. Fatigue life shouldn't be an issue either.

This lens appears to be the one used, not the one I linked to before.

B&H lists this lens as capable of 1:1 at 15" nearest focus, so 5" working distance sounds reasonable. The 35mm equivalent perspective is 73mm, so it's basically like shooting a 60mm macro only with a minimum focus distance not quite as close.

A 1.7x teleconverter is available that yields a 124mm equivalent perspective and a 28mm frame width, about equivalent to 1.28:1 on a 35mm FF. A DX camera with a 100mm will be more powerful without diopters or teleconverters. A FF 35mm with a 150mm Sigma or 1.4x + 100mm is in the ballpark.

It would be interesting to see tests proving one way or another whether the 1.7x gives up any potential IQ advantage the MF sensor offers. Remember that a 39MP 36x48 sensor has pixels with only 10% more area than the upcoming 1Ds3 so the assumption that the MF camera will have greater IQ because of larger photosites is not justified. I'd wager that, if these cameras are in any way lens-limited in sharpness, then the smaller format would outperform the larger one once the 1.7x converter is factored in (assuming the 1Ds3 isn't using a 1.4x). A 1Ds3 could be considered to be a 1.33x crop of the H3 sensor...not nearly as great as people think and a smaller difference than DX is.

Perhaps H3 teleconverters are stackable, but it seems at that point that image quality would clearly be better with the smaller format and it's more suitable supermacro lens choices.

Unless there are other options, there's no equivalent to the Canon/Nikon/Sigma/Tamron 180s/200s, no equivalent to the Sigma 150 + 1.4/1.7/2.0x converters or 2x + 100mm options. It seems that 28mm minimum frame width is a practical limit for an H3 since there are no longer lens options and diopters will shorten working distances to unmanagable levels.

On more time...

Techniques for medium format differ from their smaller (35mm & APS) cousins, with MF techniques being closer to large format.

For starters, extension rings are commonly used, and Yes, even stacked, in order to simulate how bellows work on a view camera.

Also, actual bellows are used in MF for lens movements (shift/tilt/swing) -- Another set of LF techniques -- as well as macro.

Teleconverters are generally not used as often in MF, except out in the field with Very Expensive Lenses, since MF glass (like this lens I own) has higher aperture numbers, due to the fact the lens has to spread the light out over a larger film (or CCD) surface area without fall-off, yet still be manageable.

Teleconverters are more common in the 35mm world, because even if you add 1-2 stops (1.4x & 2x), good glass with decent gathering power (larger apertures) is relatively inexpensive, such as an 80-200 f/2.8 zoom: Pop a 1.4x TC on it and you just bought a 120-300 f/4, which is still quite good.

On the other hand, I'd never put even a 1.4x on my 645AFd using my 300mm f/4.5 lens, as that would take me up to f/6.3 at only 420mm, dimming the viewfinder quite a bit... In that case, I simply mount my 500mm f/5.6 MF lens instead.

[by the way, I didn't know until just now B&H cut the price by over half on that 300mm f/2.8 monster for the 645: It was $13,900 the last time I checked a few weeks ago!]

This lens appears to be the one used, not the one I linked to before.

 

B&H lists this lens as capable of 1:1 at 15" nearest focus, so 5" working distance sounds reasonable. The 35mm equivalent perspective is 73mm, so it's basically like shooting a 60mm macro only with a minimum focus distance not quite as close.

 

A 1.7x teleconverter is available that yields a 124mm equivalent perspective and a 28mm frame width, about equivalent to 1.28:1 on a 35mm FF. A DX camera with a 100mm will be more powerful without diopters or teleconverters. A FF 35mm with a 150mm Sigma or 1.4x + 100mm is in the ballpark.

 

It would be interesting to see tests proving one way or another whether the 1.7x gives up any potential IQ advantage the MF sensor offers. Remember that a 39MP 36x48 sensor has pixels with only 10% more area than the upcoming 1Ds3 so the assumption that the MF camera will have greater IQ because of larger photosites is not justified. I'd wager that, if these cameras are in any way lens-limited in sharpness, then the smaller format would outperform the larger one once the 1.7x converter is factored in (assuming the 1Ds3 isn't using a 1.4x). A 1Ds3 could be considered to be a 1.33x crop of the H3 sensor...not nearly as great as people think and a smaller difference than DX is.

 

Perhaps H3 teleconverters are stackable, but it seems at that point that image quality would clearly be better with the smaller format and it's more suitable supermacro lens choices.

 

Unless there are other options, there's no equivalent to the Canon/Nikon/Sigma/Tamron 180s/200s, no equivalent to the Sigma 150 + 1.4/1.7/2.0x converters or 2x + 100mm options. It seems that 28mm minimum frame width is a practical limit for an H3 since there are no longer lens options and diopters will shorten working distances to unmanagable levels.

Titanium is a real Hillary! to work with...

Hillary - that one went straight over my head - care to expand ?

Paul C

Titanium is a real Hillary! to work with...

Hillary - that one went straight over my head - care to expand ?

 

Paul C

A picture is worth a thousand words...

Ok - I get the general idea......

Ta,

PaulC

Somewhere I've read that Titanium doesn't like high pressure oxygen (perhaps it becomes slightly reactive) but I'm not sure if there is any substance in this. Can anyone confirm or deny? (It does seem odd that Titanium isn't used more in housings as it should be an excellent material unless it has a drawback other than cost/machining).

AFAIK Titanium may ignite in presence of high pressure O2 (or high fO2s) at as low as 70 deg C.

Tha is not a problem when dealing with a 1 atm camera housings, unless you have a habit of filling the housing with pure O2. Why we're not seeing titanium housings has more to do with the not-so-nice machining properties of Ti.

Titanium regulators, however, are a bit scary...

//LN

Interesting, given that Ti might be a viability for fittings (ok, so at a higher cost) I was actually wondering whether it might have beneficial electrolytic properties if used on an aluminium housing as its the stainless steel fittings which eventually cause some degree of corrosion on most housings. Although given the duration (as opposed to life) expectancy of most digital cameras (dSLRs included) I'm not sure that this is the problem it was with film camera housings!!!

Yes, I did see that there was a Ti regulator made......... specification and technology defeating itself perhaps?

Techniques for medium format differ from their smaller (35mm & APS) cousins, with MF techniques being closer to large format.

Let's make this quantitatively clear. This H3 sensor is 48x36. Full frame 35mm is 36x24. That means the sensor is 4/3 wider and 3/2 taller. It's not magic. Any "technique" differences aren't due fundamentally to the larger format, they're due to the nature of the bodies and lenses that offer them. These differences in technique are PRECISELY what I'm discussing. Glad you're interested in joining in.

BTW, FF 35mm has a greater difference in size compared to DX than MF does to it, yet NOBODY claims there are fundamental technique differences there. There is less inherent quality difference between MF and FF 35mm than there is between FF and DX, at least due to sensor size. Other factors are precisely what's worth discussing.

For starters, extension rings are commonly used, and Yes, even stacked, in order to simulate how bellows work on a view camera.

 

Also, actual bellows are used in MF for lens movements (shift/tilt/swing) -- Another set of LF techniques -- as well as macro.

Extension tubes are VERY restrictive underwater, they increase the port sizes (dramatically for larger formats) and they reduce light required for focusing. They may or may not degrade image quality depending on the lenses.

In any event, extension tubes do NOT change perspective (the most glaring problem with only having a portrait macro lens), they offer only modest improvements in magnification on such short lenses, and they sacrifice maximum working distances. Extension tubes are not a substitute for teleconverters. Any mythical benefits attributed to MF do not change fundamentally how the optics work.

Teleconverters are generally not used as often in MF, except out in the field with Very Expensive Lenses, since MF glass (like this lens I own) has higher aperture numbers, due to the fact the lens has to spread the light out over a larger film (or CCD) surface area without fall-off, yet still be manageable.

 

Teleconverters are more common in the 35mm world, because even if you add 1-2 stops (1.4x & 2x), good glass with decent gathering power (larger apertures) is relatively inexpensive, such as an 80-200 f/2.8 zoom: Pop a 1.4x TC on it and you just bought a 120-300 f/4, which is still quite good.

 

On the other hand, I'd never put even a 1.4x on my 645AFd using my 300mm f/4.5 lens, as that would take me up to f/6.3 at only 420mm, dimming the viewfinder quite a bit... In that case, I simply mount my 500mm f/5.6 MF lens instead.

Chalk another one up in favor of 35mm then. 35mm has available high quality teleconverters that are usable not only because of their minimal IQ degradation but because the macro lenses are bright enough that one can afford the light loss. MF, on the other hand, by your own words, Dan, doesn't because of their macro lenses lack the brightness. Sad that's the case, since MF sure needs good teleconverters for macro.

Considering that 35mm has a 150mm macro offering f/2.8, it's a bit sad that MF can't do better than f/4 at 120mm. After all, everything else about MF is larger and heavier, what's the problem with making a bigger lens? Fact is that MF shooters don't value macro or else the lenses would exist. 35mm macro solutions consistently get down to half the size of MF, or better, with greater working distances. We NEED that capability underwater.

Subjects underwater don't change just because the camera is no longer capable of taking shots of many of the macro opportunities. If you look on a boat with a number of experienced macro shooters, you don't see them constantly shooting 50s and 60s even if they are shooting DX. Sadly, that lens is ALL that's available in MF. I have never shot a macro lens with as wide a perspective as the 120mm and have no interest in doing so. For those shots I use a midrange zoom which offers me greatly more flexibility and nearly the same frame sizes as this 120mm offers to a MF shooter. I wouldn't criticize someone who prefers a 50/60 for that purpose, but it underscores the fact that, with 35mm, we have real, useful choices.

Craig

Having shot on everything from 35mm to 5" x 4" including a variety of 'medium formats' I can honestly say that there is a REAL difference between using different formats. As the film size (sensor size) increases so the the exacting nature of the format. It really isn't all about the camera size ergonomics (I had a Contax 645 which handled exceptionally well) but move away from the 'simple' photography of landscapes and the like and everything becomes magnified in its exactness. DX format has a great deal to recommend it for underwater use and is also at the end of the day probably the easiest format to use underwater.

The comments you make in your post illustrate just why its easier to use a DX style camera; close-up abilities and the use of teleconverters on DX still produce relatively acceptable results. To use similar gear on MF requires precise technique and pre-consideration of the potential subject and/or exceedingly good teleconverter optics. On the other hand, there are differences between DX and '35mm' and '35mm and 'MF', some subtle and appreciable only be the visually 'educated', others to do with their inherent physical size differences.

As you will see from my posts, I'm perfectly satisfied that by using the '35mm' format I can achieve the images that I set out to take. I assume that Troy considers MF in the same light, but MF is most certainly not the route I'd want to take! But don't be fooled into thinking that formats are all the same, they really are not.

I know you feel that way, Paul, and we've have discussions to that end. I accept that there are differences in the qualities of various systems, but I don't accept that those qualities should be attributed consistently to the size of the format itself.

I'm as big a fan of large sensors as anyone but I firmly believe that different lenses and camera bodies can contribute greatly to image quality. The fact that MF uses entirely different lenses and is optimized for different applications means that there are factors other than imager size that contribute. Put a 36x24 sensor in an H3 and you will still get IQ differences compared to a 1Ds.

I think comparing DX to FX (if I may use the Nikon branding) is interesting in this context. Paul, you value the shallow depth of field that FX offers compared to DX in wide angle applications. Similarly, people consistently comment that MF offers a dramatic advantage over FX in this regard. The fact is that the size ratio between DX and FX is quite similar to the MF/FX ratio. FX is 2.25 times as big as DX while MF is 2 times as big as FX. People don't generally consider the difference analogous even though it is (in fact, MF is less of a jump). I consider that to be because people romanticize MF systems and attribute magical rather than technical qualities to them. As good as FX is, there are occasions where DX is better. Same is true for larger formats.

No doubt this H3 system offers capabilities that set it apart from other systems, but these capabilities are the sum of all the engineering that goes into the product, not simply the chosen size of the imager. As underwater photographers, we have to consider not just the appealing IQ it's capable of but also the limitations imposed by the system, and I don't think anyone can argue that small lens selection isn't a huge disadvantage.

Imagine, hypothetically, that one could quantify the IQ advantages of MF over FX. What would that quantity be? 10%? 50%? 100% 500%? Depends on what you value.

In my mind, and I know this will be greeted with substantial disagreement, just such a quantitative judgement is possible and it is done all the time. That's what is done by objective testing and review sites, and because of those efforts we have a really good idea what the resolving power and IQ differences are between a 1Ds2 and a 5D or D2x is, just to name an example.

If you accept that such a quantitative judgement is possible, then you can decide objectively whether a system is more desirable after you factor in all its cons in addition to its pros. I believe that when someone objects to that type of analysis it's because he fears the results. All SLRs work the same way; with the H3 you get to use a different camera box, different shutter mechanism, and different lenses in addition to a different imager. Ultimately, this camera captures images the same way as a Canon or Nikon does.

All the benefits of the larger imager in an H3 are easily squandered when the system doesn't have the lens you need for the job or if it requires you to use an IQ-robbing teleconverter to get the shot. If the only kinds of UW photography you are interested in happen to be the strengths of the H3, then I'm sure it would be a fantastic solution. That kind of photography would be limited to rectilinear wide primes and portrait-style low magnification macro. Considering those are clearly limits of MF itself, I don't see how that could be argued.

Troy,

I'm here at Splashlight Studios in Manhattan, where Hassy is introducing the H3D-II in a few minutes. Everybody who has seen your shark photo is quite impressed, including Christian Poulson, the president of Hasselblad.

Great work!

Thank you for the welcome. Out of water is 95 degrees. But u/w it sure looks alot wider. Here is a shark photo shot 3-4 ft away. shark was 8ft.

Troy,

Do you have any plans to take the Hasselblad fisheye lens underwater? Macro aside, that will surely get everyone's attention. (It's only $7339 at B&H)

Good Morning Dan,

That's awesome! Ask him if he would be interested in some images for next years PMA for display purposes for the H-series cameras. Doing something for a display panel would be great. Ask them what is the noise improvement over the H3D by their improved cooling or is it done by software. The noise level is already virtually non-existant. Flexcolor has no real sign of noise but the same file in CS3 does show some in low light conditions. I'm sure the new Hasselblad software will only get better. One more thing, ask if the GPS option can be applied to the H3D w/o a full upgrade.

Enjoy,

Troy

Somewhere I've read that Titanium doesn't like high pressure oxygen (perhaps it becomes slightly reactive) but I'm not sure if there is any substance in this. Can anyone confirm or deny? (It does seem odd that Titanium isn't used more in housings as it should be an excellent material unless it has a drawback other than cost/machining).

Paul, I have been using an Atomic Ti2 regulator for over two years with Nitrox up to 40 percent. I seem to remember you also persuaded me to sell all my Hasselblad lenses!

(Ah well... I met an old art director in the street today. He reminded me that my first advertising shoot featured a model called Rona Newton-John, who had a little sister called Olivia who wanted to be a singer. I'm getting too old for all this!)

Good morning Loftus,

At this point no. The 28mm underwater can get very close to subjects u/w and plenty, plenty wide. No distortion etc. Maybe next year with the H3Dll upgrade or the following year with who knows what they will come up with. January will tell me how I can turn a profit with u/w images then I will let u/w profits dictate repeat investments. By the way in practical terms the majority of professional photographers own alot of lenses but only use a few of them most of the time. Sounds ideal to have alot of lenses but how many times out of every year will we use all of them.

Intensly enjoying what I have already,

Troy

But John, is it just in the name.......?

I'm not sure I 'persuaded' you to sell them (I think that I suggested that the sooner they were sold the better the price you might get for them, and looking a current 500 series prices I may well have been right).

But be honest, would you still be using them? And would you take a 'blad underwater?

Any more images to share Troy?

If you follow a bunch of threads here, you'll see the fisheye lenses, 10.5 Nikon and 10-15 Tokina mostly, have become huge workhorses underwater for close focus wide angle reef and wreck stuff etc without much concern about distortion underwater. It might be worth trying to rent one if such a thing is possible from Calumet or someone.It would definitely lay to rest one of the arguments against MF.

Just my two pennies worth.

Jeff

Good morning Loftus,

 

At this point no. The 28mm underwater can get very close to subjects u/w and plenty, plenty wide. No distortion etc. Maybe next year with the H3Dll upgrade or the following year with who knows what they will come up with. January will tell me how I can turn a profit with u/w images then I will let u/w profits dictate repeat investments. By the way in practical terms the majority of professional photographers own alot of lenses but only use a few of them most of the time. Sounds ideal to have alot of lenses but how many times out of every year will we use all of them.

 

Intensly enjoying what I have already,

Troy