amphibic vs housed systemflash

Hi,

It is no question that a grown up amphibic flash (subtronic, etc.) is out of range for a housed system flash.

I am wondering how this is compared to a midrange flash.

For example, following both flashes have same color temp (5500K).

Topside guide no (m) and coverage compared:

Inon Z220: 100°/guide no 22, 110°/diffuser.

Canon 550EX: greater 85°/guide no 28, greater 105°/built-in diffusor.

So the coverage topside is not sooooooo different.

UW the Inon was reported with coverage angle of 55° by the scubacam test. I think this is realistic and would meet the statement that good housed system strobes in general would give about 50° to 60°.

If the 550EX would be housed with a Dome glass (Uwe Kiel does it upon request), would there still be a big different underwater concearning the coverage angle?

Has someone compared something like this?

thanks

Julian

I have a Subal flash housing w/ a dome glass.

Land flashes have a single straight flash tube so they don't throw as wide and even lighting as flashes with a "pigtail" tube. Inon's have two straight flash tubes, so are somewhere in between.

Underwater guide number is NOT the same as land guide number, so you can't compare them. UW guide number can be as high as 3 times stronger.

Cheers

James

Hi James,

I think you can compare the guide numbers as the Inon Z220 guide number is a topside value as well.

With Pigtail tube you mean the round flash tubes like DS125, subtronic, etc? It is clear as I mentioned that these flashes are beyond of course. No doubt.

yes, the Inon has 2 tubes. but I think there is also some strong spot when the T shape overlays (double in the center). Still have not taken my Z220 below.

What impression do you have how would your subal housing compare to for example a YS90 / YS120 ?

I still don't see a proof that a midrange amphibic flash MUST offer a better coverage as they also have just one forward tube.....

still wondering.

Julian

Generally I think that the biggest advantage of mid-level amphibious strobes compared with housed land flashes are the ease of use. UW strobes tend to have nice big switches and levers - easy to use UW even in gloves.

Housed land guns offer better compatability with the camera (such as TTL capability and high speed synch etc). Many of the housings are a bit dodgy - often because they are designed to fit several models - and often the controls do not always line up reliably. Some don't even have any controls.

In general housed land flashes do not give the coverage of a decent mid-range UW flash for wide angle. But that said, a friend of mine Linda Dunk, who is one of the best Fisheye photographers I know, lights all her fish eye images with a YS30 and a housed Niko SB26.

Alex

In terms of accessibility I have seen a lot of housings which even do not offer an on/off switch (do I have to flash into my face if I want to take a pic without flash?). I found only Subal and Seacam offering buttons on their strobe housings. As you said Alex, the small knobs do not look optimized for gloves or ease of use.

Maybe I will buy one for the 550EX and compare to the Z220. I still like the idea having the perfect compatibility with the camera. So the idea would be to get finally two housed strobes also for Wideangle.

Julian