Strobe Review: Scubalamp D-Max and Retra Pro Flash

by adamhanlon Sunday, April 25th, 2021

Scubalamp D-Max:

Scubalamp is a Chinese company specializing in dive torches. The overall product quality and prices have given them a good amount of market share. Up until now, however, they have only produced video and multi-purpose lights, so the D-Max is their first try at a flash gun.

Front view of Scubalamp’s D-Max featuring a circular flash tube and central LED light.

Scubalamp D-Max side view. Optical sensor port sticking out at the bottom.

Below are Scubalamp’s stated specifications for the D-Max strobe:

Guide number ISO100: 32
Flash output: 250 Ws
Connection: optical cable / 5 pin sync cord/Slave mode
Beam angle: 120°
Output: 8 levels: 10%, 20%, 30%, 40%, 50%, 70%, 90%, 100%
Battery: SUPE Battery Pack (4x 18650 lithium batteries)
Battery capacity: 44.4 Wh
Flashes per battery charge: 750 flashes at full power, 5500 flashes at lowest power
Power indicator light: red >30%; green<30%
Recycle time (full power): 0.5s
Continuous shooting: 15 frames continuous shooting at lowest power level. 12 frames continuous shooting at 2nd level*
Colour temperature: 5300K
Depth rating: 60m / 200 ft
Focus/target light: 5W / 500 lumens
Dimensions (length x diameter): 175 x 97 mm
Weight (land): 1195 g without battery
Weight (underwater): 120g
Do not support S-TTL or TTL

*We (probably like most people) took this part of the specification to mean 15 and 12 frames per second, however, after further clarification from Scubalamp it refers to 15/12 continuous frames taken at 7fps.

At first glance, some of these values certainly seem very promising, particularly flash output, recycle time, and number of flashes at maximum power.

Judging by the spec sheet, with a maximum flash output of 250Ws the D-Max strobe should be significantly more powerful than the likes of OneUW One 160X, Seacam Seaflash 160D, and Retra Flash Pro, which are all in the 150-160Ws class. Battery capacity and recycle time on paper are also well ahead of its main competitors.

The D-Max’s circular flash tube, similar to the ones found in its competitors, should provide even illumination, avoiding hot spots.

The color temperature of 5300K is a bit cooler than what most shooters prefer. Warmer light (lower Kelvin value) gives more pleasing blues in the background of the image so is desirable in tropical conditions. Colder light, like the one produced by the D-Max, would be very well suited to temperate waters, however. Using the included diffuser, the value decreases to around 5000K. This could be further modified by using gel filters, however, all of this decreases the light output of the strobe, as each element placed in front of the flash tube will absorb some light.

It’s important to note that this flash is not compatible with TTL and is not capable of ignoring pre-flashes produced by the camera. Either your camera or the optical flash trigger in your housing will therefore need to be able to emit a single pulse or else the flash won’t be in sync with the shutter leading to incorrect illumination of the scene. While TTL will perhaps not be missed by most advanced shooters, the lack of pre-flash cancellation is a serious limitation that needs to be considered when purchasing the strobe. Most strobes do feature some kind of pre-flash cancellation mode.

When using the neoprene cover, the D-Max is almost perfectly neutral underwater. This certainly helps with trimming the camera rig without using large floats.

What’s inside the package

The Scubalamp D-Max comes in either black or silver and includes in the box one diffuser D100, one standard ball mount, one battery and charger, neoprene cover, and neoprene cap.

Rear controls

D-Max rear panel. Power dial (left), battery compartment (top), electric sync port (bottom) and mode dial (right).

The controls are located on the rear side of the strobe and mainly consist of two big dials. One acts as a mode dial with positions for off, on, and on+focus light. The second dial allows for adjusting of flash output in 8 steps. It also features a “T” position, which manually triggers the strobe at maximum power when selected. This can be a useful feature for troubleshooting and for creating long exposures underwater. Unfortunately, without the option to adjust the power of that test flash, creative use of this feature is somewhat limited. The back of the strobe also features a display that reads the currently selected power, somewhat redundantly to the power dial, as well as an LED that indicates that the strobe is powered on and also gives an indication of battery level. There are only two levels: over and under 30% and quite confusingly, the strobe shows a green light below 30% and a red light above. For most other strobes 30% would not be an ideal threshold as entering the water with a remaining charge of, say, 31% would likely see the strobe die during the dive. However, in the case of the D-Max, due to its impressive battery life, this seems an acceptable choice as even a 30% charge will give the user plenty of flashes at full power. Unfortunately, there is no ready light on the strobe. The other two features of the back panel are the battery compartment and 5-pin sync cord connector. The fiber optic input is located next to the ball mount along the bottom of the strobe.

All labels on the back, as well as the display, end up being upside-down when the strobes are hanging from strobe arms in what’s the standard configuration for most underwater shooters. While this is not a huge annoyance, it is certainly an easy improvement for a future revision of this strobe to increase usability.

D-Max’s sturdy battery compartment cap.

The battery compartment has a double o-ring seal. Unfortunately, the battery compartment does not appear to be sealed against the rest of the strobe’s internals, so a battery compartment leak will likely damage the whole unit. This increases the importance of proper o-ring maintenance and correct placement of the battery cap. There is also no leak detection system.

Build quality

The chassis of the D-Max is made from a single piece of aluminum that appears fairly robust. The flash tube is protected by a slightly curved acrylic dome that should aid in providing a pleasingly uniform beam. The center focus light is powerful enough for any use except, of course, for serious video production. It is of similar quality as Scubalamp’s dive torches.

The dials and battery cap feel sturdy and are easy to operate without gloves. Using the dials with gloves is far more challenging as they do not protrude far from the back of the strobe. Both dials are the same length, which makes telling them apart without looking more difficult. They do click into place really nicely when turning.

Dials have a nice “click”.

Accessories

The D-Max comes with almost everything you need: diffuser and neoprene cover, as well as a battery pack and charger. The diffuser is held in place by o-ring friction, which works well when the diffuser is pushed onto the front of the strobe properly. We would generally recommend buying an extra battery as the proprietary batteries will be very hard to obtain should one of them fail on a trip or assignment. This will also help with always having one pack recharged and ready to go.

D100 diffuser mounted to D-Max strobe.

O-ring that provides the friction mount for accessories.

D-Max battery pack.

Thanks for the nice write up!!! I have some thoughts as well about the Retras.

I had years with both Inon and Sea&Sea flashes and finally last year I spent a big chunk on the Retra Pros.

First impression was that I could forget about using older Eneloops or other brands to charge them and shoot reliably on a dive. After some feedback I realized I had to use Eneloop Pros and buy them new.

I have now spent only about 30 dives with the Retra Pro (thank you Covid!).

As mentioned in the article, the flashes diffuse so well (even with an 8mm FE lens on M43) that I have passed on purchasing diffusers so far.

Coverage is now easier to achieve with the Fisheye lens and color quality and uniformity is way better than what I was used to. Huge improvement over Z240s.

Power is so strong that at full blast you have to make sure water is clear or you will get back white clouds (!). So I decided the new Reflector option on sale can be a good option to get the best water penetration for skittish animals that do not come close or other focused subjects further out in the blue. However if you buy the reflector you need to buy the reduction ring. Not sure why they did not design it to allow direct coupling to the flash (!). This is next on my wish list. Clearly most of the times you will not go over 50% of the power except for certain situations I describe later.

Ergonomics is generally great and the knobs are differentiated somewhat but they have the same shape and are both black. It would have been nicer a different shape and/or color knobs.

The Bluetooth wireless connection is great and it gives you a fantastic option to upgrades, total flash count, and voltage levels.

For protection I would rather use some self made neoprene (plenty of that at my place) with a cover that can be flipped out and back on the flash body with some velcro. Easier to use and cheaper.

The Supercharger is a good investment since after 2 dives flashes are already in the red zone. If you plan 2 dives or shooting well lit widest angles the 4 AAs Eneloop Pros may not make it. I think a new design may want to look into the Li-ion 18650s as a longer higher density battery. Also the Retra Pros will not work well with non-Eneloop batteries so the flexibility of using more popular AAs is really not there. These ones on my wish list as well (!).

One of the interesting feature I am now using successfully is the HSS (high speed sync). I bought the Turtle sync which has both HSS support for both manual and TTL modes. My camera shoots up to 1/4000 and gives some exciting creative choices underwater!. However this feature will use more power.

LSD options may also be worthwhile if you like some special snooting effects and attach directly to the Retras. This will also use more power I believe but have not tested it.

Overall a great new evolution and lots of interesting options. Power is where this flash has a bit of a weak point in my opinion. I think the optimal battery needs to be able to do 2 or 3 dives without having to worry whether it's going to get to the end of the day or not.

Andrea

Posted by Andrea Severino on 2021-04-26 09:51:51