Tag Archives: Sony rx100m2

Leak Sentinel V3 for RX100 Mark II – Review and Stress Bench Test

Following the failed test on the Nauticam Electrical Sync Cord bulkhead I was out in the market to check what else could be done with the M16 port on the RX100 Mark II housing.

I bumped into the leak sentinel while at the London Dive Show. As you may know Nauticam provides now a vacuum system with temperature compensation on all new micro 4:3 and DSLR housings. Also older models can be retrofitted but not the RX100 because essentially the moisture sensor is much simpler.

So if the Nauticam housing has already a moisture sensor why bother adding a vacuum test. The advantages are numerous:

  1. A moisture sensor still requires the housing to be put into water to be tested
  2. A moisture sensor starts beeping when water has already made its way into the housing, if you are in a situation where you have a mandatory safety stop or a deco stop you don’t want really to have the additional stress of a camera flood.
  3. With a leak sensor you can check the integrity of the housing before the dive and without putting it in water
  4. You can rapidly change battery and the likes and not worry if you have compromised the seal of your housing

With all of this in mind I went off and contacted Vivid housings

After an email exchange about the design of the product I was convinced that it was worth getting it so I ordered one and after just 3 days it turned up in my post directly from Slovenia.

The system comes with an M16 adapter to screw on the housing bulkhead. The best way to remove the cap on the Mark II housing is using a CR2032 battery like the one of the moisture sensor.

I set up the system on the housing as in the featured image and started my preparation. It takes 3 pump strokes to get a green light and the instructions say to add between half and a full stroke to make sure it is not on the edge. I had 4 full strokes.

I prepared the housing and camera in a room at 21C and waited 20 minutes before putting it in water at 15C.

I then put the camera in video recording mode for one hour, the Rx100 has a limit at 30′ so I had to record two files. After one hour the system was still showing a green light I took it out of the water and follow the depressurization procedure and extracted the camera. Measuring the temperature inside the battery compartment the sensor indicated 28C.

Now this made me think to the fact that this solution, although equipped with a temperature sensor, does not actually manage temperature compensation. If you know anything about physics you know that the following is true for an  gas also known as Gay Lussac law

the pressure of a gas of fixed mass and fixed volume is directly proportional to the gas’s absolute temperature

As our housing is rigid and not compressible this means that the ratio between temperature and pressure is constant.

This also means that if the temperature increases because the camera warms up with use the vacuum will drop (pressure increases), this could create a false positive.

I therefore performed the following steps

  1. I immersed in water at 32C and started shooting a video clip.
  2. After around 50 minutes the led started to alternate red and green. The camera has the temperature warning indicating a possible temperature close to 40 degrees
  3. I kept the camera in water pretty sure there was no leak and then at 60 minutes took it out of the water
  4. After few minutes outside water in a room at 21C the light went back to green
  5. The camera temperature in the battery compartment was 36C
Water Temperature Measure
Water Temperature Measure
Temperature warning
Temperature warning

The ambient pressure was 1016 mpa so I estimate I created around 750mpa inside the housing with 4 full strokes, however as the camera sustained an increase of 19 degrees from 21 to 40 the pressure sustained an increase of 6.5% bringing it in the warning area of the leak sentinel and generated a false positive.

Now there are a few considerations to be done:

1. If you shoot pictures even firing the flash is unlikely to get the camera as hot as when you shoot video
2. The water in the dive will seldom be 30C anyway
3. It is preferable to prepare the camera in a temperature as close as possible to the diving temperature and in the driest environment available
4. It is possible to estimate the amount of vacuum each pump strokes gives and compensate for the temperature changes

The worst possible scenario is a video camera housing prepared in an air conditioned environment this is the only scenario where temperature compensation is useful.

Generally the suggestion of the user manual to give one or half pump strokes should be changed. Say that I have a large housing and it takes 10 strokes to create the vacuum, I would suggest another 3 strokes is diving in warm water otherwise the possibility of false positives is increased.

Vacuum Pump
Vacuum Pump

For what concerns the RX100 and only for very warm water shooting a lot of video there is a theoretical possibility that the camera overheats, and if the housing had been assembled in a much colder room, this gives a false positive.

To minimize this possibility prepare your housing at the normal ambient temperature of your dive site is generally the best practice for tropical diving. I also do not recommend practices like preparing your housing in a cold air conditioned cabin, some people think they avoid condensation not thinking that a 20+ degrees thermal shock does do any good to the camera.

Ultimately at €200 including worldwide shipping I can definitely recommend the leak sentinel to all RX100 users. Considering the cost of your investment even at the price of the RX100 Mark II of $750/£649/€699 this is a good tool and more than anything give you the extra reassurance of having a watertight housing, and also helps you in all your situations where you have a battery change or you have to open the housing before the end of your day.

Which Fisheye Lens for the RX100?

Recently I have started building my RX100 Mark II photo rig and as part of this I had to choose a wet fisheye lens.

For video I do not like the barrel distortion of a fisheye lens, and on top of that you can’t attach a push on filter to a dome so for me those are two big no when it comes to the RX100 and its white balance error woes.

For still instead I shoot only RAW never white balance in the water and a fisheye lens is required so that I can have human size strobe arms when shooting close focus wide angle at distances between 0 and 16”.

I will focus my discussion on the Nauticam housing starting off with a 67mm thread and go from there.

Currently there are 3 options on the market for the RX100 and come from 3 difference manufacturers. I will go through each one briefly and then we will look more in detail at the two I consider best.

The first lens is the FIX UWL-28M52R, this lens is the smallest of all and was originally design to nicely complement the form factor of a Canon S100 in a fix housing, hence the 52mm thread. The lens has a magnification factor of 0.41x and a diameter of 126mm including the hood, the lens is actually much smaller at around 90mm.

Fix has introduced this lens in 2011 as a replacement of the previous UWL-04 model for two reasons, the first is to have a smaller lens as the UWL-04 was a too big in comparison of the housing, second probably cost though this was never declared. However other people tests and plenty of in water images show that this lens is actually worse than its predecessor. It is also smaller making split over-under shots more difficult.

When Fix withdraw the UWL-04 the manufacturer of the lens continued the production and finally put it back on the market under the i-divesite brand. This lens is the same as the Fix except the label.

Both lenses the old and new fix are pretty much a copy of the old Inon UFL-165, both made of 4 glass elements and an acrylic dome with hard anti scratch coating.

Here is a set of shots for the UWL-04 and the various parts in the box.

UWL-04 Box
UWL-04 Box
UWL-04 package contents
UWL-04 package contents
UWL-04 Hood Cover
UWL-04 Hood Cover
UWL-04 with ring
UWL-04 with ring
UWL-04 back lens
UWL-04 back lens

The last lens on the market is the Inon UWL-H100 with dome. This lens is available with an M67 mount and with an LD bayonet mount. Due to the size and weight of those lenses in water (100 to 500 grams weight and diameter between 125 and 152 mm) a bayonet mount is my preferred choice.

The Inon lens is actually made entirely of glass, the dome is the biggest at 115mm for the lens with an overall diameter of 132mm. This lens is the more suitable to split over under shot and promises a better contrast and less flare than the other lenses with plastic domes. Inon had some concerns about plastic domes and flare following the performance issue of their UFL165 so went for 100% glass for all next generation lenses.

Vignetting with RX100

In certain conditions all those lenses actually have some vignette in water. Despite what you read on shop websites if you look at real pictures there is a bit of that.

The Fix and Idas lenses have an issue with the lateral hood, the shots look clear of vignette on land but in water the magnification of the hood petals makes them show in the picture, we are talking a minimum crop required around 1% and usually on one side. The Inon UWL-H100 has a different issue and it gives in specific situations a tiny bit of vignette in the corners, around 2% of the image needs to be cropped. Both lenses will not vignette when image stabilization is deactivated, the image stabilizer tends to aggravate the issue so if you are obsessed switch it off and try to be steady shooting at speeds of 1/125th of a second or faster. For example on the amount of vignette see the following

UWL-04 note the vignette left center
UWL-04 note the vignette upper left center
UWL-28M52R again vignette on the left upper side
UWL-H100 vignette in left corners

I would like to thank Alex Tattersall, Tamas Plotek and Troy Williams for those in water pictures.

Inon UWL-100 28AD

Inon has another lens that is suitable for the RX100 and is the UWL-100 28AD a lens originally introduced in 2005. This lens has a smaller rear element than the UWL-H100 and it is not suited to many cameras with a very large lens aperture. The RX100 however works fine with this lens and contrary to the newer UWL-H100 this lens does not vignette in water or on land. The reason is that the de-magnification of this lens is less than the newer lens 0.63x vs 0.6x. This is the lens I have chosen for my RX100 Mark II and I will compare it here with the UWL-04 I have recently bought for my Canon S95. There are no substantial differences between the UWL-100 28AD and the UWL-H100 in terms of optical quality.

Here are few pictures to compare the lenses, take into account that whilst the weight on land is comparable, once in water the Inon lens is heavier at 400 grams versus 160 of the UWL-04.

UWL-04 UWL-100
UWL-04 UWL-100
UWL-04 UWL-100 profile
UWL-04 UWL-100 profile


Image Quality

There is no need to take the lenses in water to compare image quality generally things get worse in water not better so it is sufficient to take a shot on land and see how that goes to have a relative comparison between two lenses. In this example the cameras are on a table exactly in the same position when the shots are taken and use the same settings of ISO, aperture and shutter speed.

The first impression is that the UWL-04 is a tad wider but more rectilinear, the Inon lens has definitely more barrel distortion and is more a fisheye than the UWL-04 is. Looking at mid upper frame you can see that at diagonal level the UWL-100 28AD is actually wider than the UWL-04 that remains wider horizontally. This means looking at the specs can be misleading and results depend on the camera lens combination.

So how do these lenses compare when it comes to corner sharpness and flare?

This is a shot with the UWL-100 in very harsh conditions with sun-rays hitting the lens directly on the dome, you can clearly see the ghosting that comes from it.

UWL-100 Sunlight
UWL-100 Sunlight

This is the same shot in the same place taken with the UWL-04 you immediate notice that the ghosting has a green color. This is most likely due to lack of anti-reflection coating inside the dome and to the color of the inner lens mount.

UWL-04 Sunlight
UWL-04 Sunlight

Looking at the image the picture taken with the Inon has a clearer ghosting but then is sharp in the rest of the image, the UWL-04 image has flare around it with comparable less contrast as we move from the center to the corners.

The other two images are a crop in the corner, you can see that despite the high level of distortion you can still distinguish some detail of the small grass bush in the Inon image, the UWL-04 instead is softer and the bush is basically a uniform green shape with no detail at all.

UWL-100  Crop
UWL-100 Crop
UWL-04 Crop
UWL-04 Crop

Update 28 Feb I have taken some shots with the UWL-H100 and the UFL165AD here are the overviews

Inon UWl-H100
Inon UWl-H100

The UWL-H100 is actually wider than the UWL-04 with the Sony RX100 despite the advertised 144.5 degrees versus 165 of the UWL-04. Has the same level of detail of the UWL-100 28AD

Inon UFL-165 AD
Inon UFL-165 AD

The UFL165AD flare issue is obvious in this shot both lower corners are compromised, this confirms why the UWL-04 is the best option for the Canon S series in terms of flare or vignette.

Looking at the UWL-H100 crop you can see the vignette more apparent in the upper corner and the image sharpness, it is possible that with an M67 mount there is no vignette with a Nauticam housing in most conditions, with LD mount you need to turn image stabiliser off or crop. Considering this is the widest lens it is not a big issue. Once cropped the UWL-H100 gives still the widest field of view but someone maybe be annoyed by this. Zooming in results in the same field of view of the UWL-10- 28AD


The Inon lens presents the benefit of a bayonet mount, although the lens is heavy it can be removed in water quite easily, the UWL-04 has some issues whereby the adapter ring would unscrew instead of the lens, this can be avoided fixing the adapter on the lens but then there is no lens cap that would fit the larger M67 screw in the box so you need to buy one yourself, generally the size of the petals make this lens impossible to handle in water and is more like diving with a dome port. It has to be noted though that you can zoom through with both lenses so still continue and take portrait shots and close ups. Obviously for real close or macro you do need to take the lens off which with the UWL-04 you can basically forget.


The UWL-04 costs $460 in US as shown here with dome cover and step down ring, and £362 in UK. The Inon UWL-100 28AD with dome costs $907.80 including an M67-ADF adapter in US and £775 in UK. All in all the Inon is around near to double the price of the UWL-04. The UWL-H100 is even more expensive at $970 for the M67 version and $942 for the LD bayonet, you then need to add $160 for an adapter for a total of $1,102 that is a lot of money another reason for the 28AD version.


The Inon is the best lens for the RX100 and there is no doubt, however it costs more than double the UWL-04 not everybody will be able to afford it. The UWL-04 is a somewhat basic lens that lacks sophistication and is essentially not removable in water but comes at a great price. In terms of field of view the lenses are very similar with the Inon lenses having more fisheye distortion and a wider diagonal field of view. The UWL-04 is more rectilinear and as consequence has less field of view diagonally. Only one lens has zero vignette at the wide end and this is the UWL-100 28AD with dome.

In Water Shots

I don’t have shots in water yet pending my next trip but two galleries that give an idea are here:

For the Inon UWL-100 28AD with dome look at my Red Sea Gallery https://www.flickr.com/photos/interceptor121/sets/72157645375379256/

For the UWL-04 instead this is an excellent one


The second shooter has got rid of the UWL-04 to buy an Inon as not happy with corner sharpness!

My perspective is if I look at the pictures I can barely tell the difference however looking close the Inon lens is sharper at one f/stop less, the UWL-04 requires stopping at f/8 or smaller, you can happily shoot f/5.6 with the Inon which means you need less light and less strobe power.

Sony RX100 Mark II Bulkhead Connection Flop

In this post I will investigate for your enjoyment the bulkhead connector available for the Sony RX100 Mark II and will see why this is unfortunately an accessory that is not worth buying. There are other ways to put the M16 port to use for example with a leak detection system but if were thinking of firing strobes using electrical sync cords then think again.

I was today at the London International Dive Show where I met Dr Alex Tattersall of Nauticam UK that also introduced me to Catherine Lai, daughter of Edward CEO and founder of Nauticam and herself operations director.

I felt a bit sorry when I had to explain why the bulkhead was not a workable solution and if you have a look at the youtube video you will understand why, this has been shot by my fiance’ on an iPhone so apologies for the portrait format and occasional shake.

Right so if you didn’t manage to hear the audio or understand the subtitles here is the plain text explanation.

The bulkhead has a single X pin that connects to the center of the RX100 multi-shoe, now this is the same interface that is on the newer Nex and on the A7. The Sony multi-shoe has a complex 21 pin interface that used with compatible accessories can trigger an external TTL flash.

In order for an external device to be recognized the interface of the connector need to connect to the 21 pin slot not just to the center. Nauticam bulkhead adapter is not so complex and only connect only on the center pin.

So the result is that the external connection is not recognized and if you leave the flash set to fill flash, as you would do with an optical connection, the internal RX100 flash pops out and fires away negating the benefit of the electrical connection.

So in order to make it work you need to set the internal flash to OFF. As the pin on the multi-shoe is always live this works perfectly so when you press the shutter the nikonos interface triggers the external strobe which is what should happen.

The little but significant inconvenient is that if you set the flash to off the LCD goes pretty much black as the RX100 has live view on the LCD and only lights up when you half press the shutter. This means is practically impossible to compose any shot unless you have a really bright focus light or there is sufficient ambient light. In any case for a close focus wide angle shot that you will take with this camera with apertures between f/8 and f/11 the screen will look pitch black as in the video even if you set the LCD to sunny weather.

Whilst the A7 and Nex have an option to disable live view in the LCD, the RX100 does not have such option so you are pretty much done and this accessory is not worth buying as it also introduces an additional point of failure for the housing and one for each strobe.

So the supposed big advantage of the Mark II goes out of the window, time to despair? Not at all!!!

As previously anticipated in my first impression post https://interceptor121.wordpress.com/2013/07/27/sony-rx100m2-first-impressions/

I had the impression that the internal flash was recycling much faster than the original RX100, well I have done some tests and I can confirm what imaging-resource has measured: the flash recycling time at full power goes from 7.2 sec of the RX100 down to 4.4 seconds of the Mark II.

Now this is significant because after your shot you need anyway 2 seconds to recharge the strobes and look at the image preview after the shot and probably another 2 seconds to recompose the shot, at that time the RX100 Mark II will be ready to shoot again at full power.

The improved CIPA rating of the Mark II also means well in excess of 200 shots at full flash before having to change the battery so there is no big deal that the electrical option is not workable, get yourself a twin set of Inon Z240 (my current favourite) or Sea and Sea YS-D1 and you will have no issues compared to any other compact as the RX100 Mark II has the highest CIPA rating of all compacts on the market that are good underwater.

In fact the most significant improvement of the RX100 Mark II in addition to the better performance in low light is certainly the strobe recycle time, from 7.2 to 4.4 is nearly a 40% improvement and the Mark II is faster to recycle than a Canon S120 although not as fast as the G15 or as fast as the Panasonic LX7 or Olympus XZ2. However we are talking about 1.2 seconds difference I doubt that is such a big deal

Clearly the RX100 Mark II is the best compact camera for both still and videos and I look forward to shooting more stills with it.


Sony RX100 – Which close up lens gives real macro?

As we know the Sony RX100 cameras, we will refer to both Mark I and II as the lens is the same, do not offer the best out of the box super close up performance.

To be clear no compact camera really does macro, as no compact can capture an area 36×24 mm in size without being on top of the subject and having a shadow cast on it.

The RX100 however are particularly unexciting as the capture area is pretty large at 76x51mm at the minimum focus distance of 5cm. This means a reproduction factor of less than 1:2 so things are half life size in traditional terms.

In water the minimum focus distance increases and so does magnification so performance is all in all the same.

This means that a typical small subject like a medium size nudibranch measuring 4cm will fill a bit more than half the frame, not great.

The problem can be addressed by close up lenses that have a set power that determines the focal length and working distance where we can use the full camera zoom.

So the close up lens sets the working distance whilst the camera zoom sets the magnification.

A typical close up lens will have a power of 5 or 6 diopters with a working distance in water of 200 or 165mm, what does it mean for the RX100?

I have done some testing in water using a ruler and an Inon UCL165 this is the result:

Single +6 diopter Inon UCL165
Single +6 diopter Inon UCL165

Our capture width is now 46mm so our 4cm nudibranch will nearly fill the frame. The working distance of this lens is 165mm so this is a very versatile solution as most critters have no problem being approached so close.

What happens with a +10 close up lens with a focal length of 100mm, this is another test

+10 Diopter UCL100
+10 Diopter UCL100

A +10 diopter like the Subsee or Inon UCL100 achieves exactly 35mm so life size macro. However a lens like this will not focus at longer focal distances without zooming out, furthermore there are plenty of subject that do not need this magnification.

Close up lenses can be stacked so this is the result of two + 6 diopters

Two stacked Inon UCL165
Two stacked Inon UCL165

The width is now 32mm which is 1.1:1 so more than macro. This is adequate even for pygmy seahorse and with the incredible resolution of the RX100 cropping is not a big issue. Working distance is around 8.5cm which is still tolerated by small critters.

For completeness I have also tested a +16 combination

16 Diopters
16 Diopters

At around 26mm this is 1.4:1 so real super macro, the working distance is however only 6.25cm which is really close and will scare most critters away.


  1. Without any close up lens the RX100 can only capture 5cm objects without extensive cropping
  2. A close up lens with a working distance of 165mm allows for most of the critters we consider small but without super macro effects unless cropped
  3. Two stacked +6 diopters offer super macro and can also be cropped for more suggestive effect
  4. A single +10 close up lens achieves real macro however it is not versatile enough for every day usage
  5. Stacking lenses does introduce chromatic aberration but this can be eliminated in photos and is barely noticed in video

Pay attention when you select your close up lenses that the focal distance that is in the specification is measured in water otherwise you will find yourself with a useless purchase

Sony RX100 Mark II – Nauticam Housing Review

I have just received this week the NA-RX100II housing also known with product code 17408

This housing is essentially identically to the already very successful NA-RX100 more specifically it looks identically to the NA-RX100V video version.


This looks apparent if we look at the left side of the housing where a screw can attach a bulkhead

HDMI/Electric Sync port
HDMI/Electric Sync port

According to Nauticam you can attach both the SmallHD 4.3 LCD monitor to use as external monitoring for video or an electrical sync cord to attach a strobe via a hot shoe 5 pin connector. This will not support TTL but will allow to fire an external strobe without triggering the internal flash. This means that there will not be any issue of recycle time especially true at wide angle or when using strobe with edge lighting.

Now I believe this is great news for those underwater photographer that are downgrading from DSLR as this was probably one of the key limitation of the RX100 that will now be overcome.

Remember that the RX100II seems to have other significant improvements with respect to the Mark I in terms of corner sharpness that can make this already excellent camera an absolute killer.

I wonder if it is possible to enable and disable the hot shoe and use both electrical and optical connectors as in macro TTL the camera performs very well indeed and this would only be available with optical connections.

If you are interested in the mini video review of this housing you can find it here

I will do some tank tests for corner sharpness in the next days so stay tuned

The housing is priced at £699 in UK as it was with the Mark I so should be $950 in US. Great value for the additional bulk head port!

Update the M16 port on the side will have an hot shoe accessory but won’t have an HDMI bulkhead, this because there is not enough space to connect the HDMI cable on the bottom of the RX100. The V version will have some more space under the camera to allow the cable to go in