emptech

I ended up shooting manual, the attached photo was shot at 1/125 sec @f22, iso 800, at "turtle heaven", Kona, Hawaii.
The puffer fish was deep in a hole, was unable to light up with both strobes, hence the shadow.  I'd post the photo but a little confused, does wetpixel host the jpg or do I have to link to it from another site?

Problems solved as far as the strobes go, Canon seems to have a problem, just best to avoid aperture preferred.

Jim

Hi Jim,

You've gotten some good explanations of why the strobes aren't providing enough light. The settings you're using are adequate for ambient light. There's enough light for exposure without much flash so the camera shuts the strobes down early. Take the camera out of program mode or aperture or shutter speed priority and use manual mode to control both shutter speed and aperture.

<snip>



Good luck,
Dave

Followed advice from your responses, from this site and another.  Shutter preferred worked but couldn't predict the desired f stop, went to manual, 1/200 @ f22, iso 800, seems to be happy.

Next improvement needs to be sharper photos, using a Canon 17-85mm lens with a +4 diopter.  Kind of wish I'd be using a real macro lens, since most of my photos are within three or four feet of small targets.  But, with a macro lens I'd be locked in and couldn't do wide shots.

Somebody suggested using an iso of less than 800 to get sharper photos, need to try that, unfortunately, after taking the shot, don't know how much of the strobe was used.  Might try 400 for a few shots and look at the histogram?

Diving again in the morning, will work on some more shots.

Thanks for the comments and suggestions =

Jim

Not familiar with the 7D controls, is there room on the housing where an additional control
could be added? Ikelite will sell new controls, if you were not concerned about modifying
the housing, would this work for you? If you don't have the facilities (most people don't),
wonder if Ikelite would do customizations?

Many years ago when I built my first housing, first heard about Ikelite as a source of controls
even before I ever bought their housings.

Jim

I'm following along. Being fairly new to DSLRs and a complete newbie to DSLRs underwater, the Q button and multicontroller is my go-to for adjusting settings in manual mode. I'm hoping there is some kind of workaround so I don't have to plunk down the cash for a Aquatica or Nauticam for my upcoming Sipadan trip.

Bo:

It's a possibility, but I'd only do it if I had a spare backplate. Ikelite said they wouldn't sell me a backplate from
a different model housing, but wonder if they would sell a replacement plate. If so, that is an idea, I could mill
out a polygon in the middle, leave a place for an O ring, and machine a piece to fit in the middle, held by screws
drilled and tapped.

I don't think I'll do it, but seems like a reasonable idea.

Thanks - Jim

Have you maybe thought about cutting out the center of the backplate (keeping the original Ikelite outer) and replace it with another fitting and sealing plate with eye piece and controls in proper position? If you have basic machine shop access, it can be done. If you try this modification, please report on DIY forum.

Cheers,

Bo

I found my own answer, had a chance to try the 5D with the housing. The 5D is slightly
wider than the 30D and slightly taller. The width was not a problem but the viewing port
on the rear would be too low to align with the ocular on the camera. The buttons to the
left of the LCD were slightly off. It would appear though that if Ikelite would sell just the
rear plate, I think the housings would interchange, but they refuse to sell just the back
plate. A new one could be machined, but because of the curves, short of having CNC
equipment, it would be difficult but not impossible.

So looks like I'll have to stick with the 30D, which is not a bad camera at all.

Jim