Samples: Inon D-2000 vs Z220 + DA2 (Heinrichs)

I had the opportunity to play around a little with the new Inon D-2000 strobe.

I have taken a comparison sequence (on land) with the Z220 driven by DA2 (Matthias Heinrichs)

If someone would like to see the results:

http://www.calypsophot.de/d2000_da2/d2000_da2.htm

Julian

It appears to me that Matthias has beaten Inon in this test.

Over the entire range, the DA2 seems to have better exposure. Was this your opinion as well?

Consistency of the TTL exposure of the Matthias' DA2 is superb...

Over the entire range, the DA2 seems to have better exposure.  Was this your opinion as well?

yes, focus light / laser on/off .... DA2 was always spot-on.

We studied this issue for a while because we were perplexed why such results would occur with D-2000 S-TTL, especially when even a year of pre-release field testing did not show such results.

So, we tried to recreate the problem of inconsistent exposure, replicating the test parameters, trying to determine the cause.

Of all the factors, the most significant we found were not placing the fiber optic in the right position relative to the camera’s internal strobe, and not using the red focus light seal. This resulted in incremental exposure inconsistency similar to these test results.

We appreciate people with time and interest testing our strobes but unfortunately sometimes the test parameters are wrong, leading to inaccurate test results, which in turn can create a biased and incorrect opinion. Please test with the manufacturer’s recommended parts and configuration.

Here are the necessary conditions to achieve proper exposure with S-TTL, as it was designed.

1) Fiber optic cable must be positioned correctly. Inon “Optical D Cable/Cap” fiber optic kits have a fixture to securely position the fiber optic directly in front of the camera’s internal strobe. This fixture also has a mirror coated plate to reflect internal strobe flash directly into the fiber. This enables the camera’s internal flash complete (optical signal) strength to be transmitted to the D-2000.

Not placing the fiber optic cable properly can result in inconsistent exposure.

2) When shooting in S-TTL and using the Focus Light, the red focus light filter seal should be applied for optimum TTL exposure accuracy. The Focus Light does not turn off during the pre-flash sequence (both the camera’s and D-2000’s preflash). So it is contributing to the total preflash light which is reflecting off the subject, passing through the camera’s lens, and being metered by the camera. However for the main flash sequence (both camera and D-2000) the Focus Light does automatically shut off so it does not influence the exposure. But since the camera has already metered the preflash + Focus Light light it will tend to calculate its internal strobe main flash duration just a bit shorter to account for that little extra light it saw from the Focus Light. The result will be less than “correct” exposure. Granted, it is a small influence, but the closer the strobe is to the subject and the more directly the Focus Light is pointed at the subject, the greater the effect will be. To minimize the Focus Light as a factor Inon provides a red seal for the Focus Light, to reduce Focus Light portion of the total preflash light the camera meters through the lens.

3) The camera’s internal strobe flash should be completely blocked, preferably with “Inon Clear Photo System” Film, just allowing the non-visible wavelengths to pass. With S-TTL, the D-2000 exactly replicates the duration of the camera’s pre-flash. With Clear Photo Film installed on the camera’s strobe, the camera thinks it is seeing its own preflash, when actually it is the D-2000’s. Optimum use of S-TTL does not include exposing the subject with the camera’s internal strobe. Clear Photo Film is included with each Optical D Cable/Cap fiber optic kit, and should always be attached to the camera.

Not related to exposure consistency, but other good reasons to use Clear Photo Film:

A) Effective use of external strobes means getting them off to an angle, to create shadows, texture and give the subject more three dimensionality. If internal strobe light reaches the subject, it will just fill the shadows you were trying to create in the first place!

B) Internal strobe flash is a major source of backscatter, and lens flare & ghosting in some situations. Clear Photo Film solves those problems.

We did the test ourselves, but with all the recommended conditions. Test results are here:

http://www.inon.co.jp/e_pdf/SampleImagesOfSTTL_En.pdf

Exposure was consistent as expected.

Other comments:

There is a lot of discussion about how great “TTL” exposure is, and certainly in some shooting situations it is nice to have. But there are times when you will want to fine tune a shot, or maybe just experiment, tweaking the exposure up or down a bit. The D-2000 allows that with a simple dial on the back of the strobe head. Just rotate dial right or left. With the D-2000 you can have TTL and quick access to flexible exposure compensation without having to fiddle with a finicky housing/camera control.

Word of mouth satisfaction of Inon performance and reliability is what we have built our reputation on for the last year. But for the D-2000, a new product with no reputation yet we had to defend it from inaccurate claims. I hope we will see more positive comments and feedback from users showing that S-TTL really works well. That’s what counts: results. In fact, here are some nice results:

http://diver.net/cozumel_2004/

Thanks for bearing with me on this and I hope you get some great images, whatever strobe system you use.

-Mark Rupert

Inon America, Inc.

Hi Mark -

Thanks for that important information on the D2000. The lighting from the test image looks very consistent over the entire aperture range for that camera - very impressive! The cozumel gallery is equally impressive with the d2000 and s-ttl. Its pretty easy to blow out the lips of grey angels and the sand in those eel shots..and you dont get many second chances in cozumel as you drift by your subjects! Exposures look good for a lot of situations that I have had difficulty lighting in the past. D2000 looks like it will be great additon to INON product line!

Michael Palasz

Hi Mark,

Thanks for the D-2000 advice. We'll be using it with the Sony P150 tonight in the pool. The one annoying feature of the system is the clear photo film, I'll be rigging up a special mounting for that to hold it against the built in strobe without having to attach anything to the camera.

At the moment, the Sea&Sea extension lens mount which is attached to the housing blocks the stray light, having adapted the Inon fibre to terminate in the Sea&Sea "plug".

I'll try to post some of the results.

Regards

Martyn

I hope we will see more positive comments and feedback from users showing that S-TTL really works well. That’s what counts: results.

I agree, results are important. In real world use, the differences in Julians test wouldn't be noticeable, as well. No one does a exposure series over the entire aperture range of a single subject UW. But such tests shows if the system works at all.

BTW, have we ever seen such tests with an Ikelite Product? I do not mean the Haas' sample pictures, I mean an exposure series with the ETTL conversion circuit or the TTL controller for example?

Anyone?

We appreciate people with time and interest testing our strobes but unfortunately sometimes the test parameters are wrong, leading to inaccurate test results, which in turn can create a biased and incorrect opinion. ... But for the D-2000, a new product with no reputation yet we had to defend it from inaccurate claims.

I haven’t used the red seal for the focus light because naturally I do expect an "automatic" focus light to turn off during the pre- and mainflash as DA2+Z220 do feature.

My understanding was that the red seal is advertised as a filter for whitebalance compensation with certain cameras. Didn’t find something different due to the lack of a user manual.

I have stated before (above) that the D-2000 results without focus light were better. I have added them now with a few lines (English as well now): http://www.calypsophot.de/d2000_da2/d2000_da2.htm

I can not confirm suspicion that optical cable was not positioned correctly towards camera internal strobe.

So I am not sure what to do more than holding the cable directly into the camera internal strobe as it would have been the case with supporting hardware (which is not available, Inon does not provide S60 mounting hardware support).

It is clear that small topside exposure deviations with short distance and focus light representing approx. 50% of the environmental light are reduced in real underwater world. But maybe still present when doing macro night dives without the red focus light seal.

DA2+Z220 are different here.

In general it is nice when manufactures do provide information on how their products work.

However, regarding "wrong test setups" this test shows that DA2+Z220 do not care about unfiltered focus light influence during preflash.

regards,

Julian

Thank God for Wetpixel!

I have just made the same mistake as Julian. Using the focus light (without the red filter) during a TTL test. I also got increasing exposures as I racked up through the apertures (f4.8 to f 8). Although all are acceptable and easily correctabe in Photoshop. See below.

I'm sure glad that we have discussions like this here. Most helpful. I'm off now to get it right! I'll report back!

This time I'll concentrate more on the test and less on the subject.

Alex

p.s. I still cannot figure out how the Strobe can create a TTL underexposure (when you use the TTL compensation dial) without being connected (apart from the fibre optic) to the camera. But it does - and it works well. java script:emoticon(':?')

Just had another go in the pool.

This set taken without the modelling light on show a much better TTL performance from the D2000 that is pretty much consistent across the aperture range. This was not a perfect test - I will redo this in the ocean in the next few days.

There is a slight over exposure at f8 (because ambient light is having a similar effect as the focus light would during the preflash and causes a overexposure during the main flash). This is mainly an artifact of shooting in a shallow pool in the tropics. On a normal dive this would not be such a problem and could easily be countered by adjusting the TTL compensator.

There are also over exposures at the large apertures most notable at f2.8. This is typical of all cameras when they are not able to quench the strobe quickly enough to create the same exposure. This would have been overcome if I had used a longer strobe to subject distance, for example.

Alex

Just to show that large aperture TTL overexposures are pretty normal. Here are some test shots from the D100 with a dTTL flash gun. Again at f2.8 the camera could not quench the strobe fast enough to prevent over exposure. This could be avoided by using a longer flash to subject distance or having a darker subject etc

I still cannot figure out how the Strobe can create a TTL underexposure  (when you use the TTL compensation dial) without being connected (apart from the fibre optic) to the camera. But it does - and it works well.

extending the mother strobe’s lightning duration with a certain gain factor and a delayed output – both would enable +/- compensation. Have suspected the first method in the article.

There is a slight over exposure at f8 (because ambient light is having a similar effect as the focus light would during the preflash and causes a overexposure during the main flash).

The difference is that true ambient light is present all the time (during pre- and mainflash) and therefore completely taken into account by the camera metering system. So ambient light does not fool the camera / TTL system (modern matrix systems). The D2000 modelling light fools the TTL system as it is present during preflash but turned off during mainflash (only in conditions where the focus light represents a great amount of ambient light to the system during the preflash). Not calculable for the metering system. I guess ambient light might no be the reason for the very slight deviation @f8.

Julian