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A900 Newbie Flash Question

goonygoogoo

New member
Hello all. I'm about to receive an A900 this Thursday and have a question about Sony's Pre-flash TTL system.

When using bounce flash with a dedicated Sony flash, I've read that Sony goes to pre-flash TTL mode. My question is how accurate is the system in getting exposures correct, especially when used with white or dark subjects like a bride and/or groom in a wedding? Any tips? Is there a flash exposure lock?


Regards,
George
 
It works as well as can be expected, e.g. you need to apply comp if there is a lot of black or a lot of white in the frame. You can adjust ambient and flash compensation on separate scales using the quick-navi system. It's pretty straightforward.
 

gsking

New member
Dave is correct.

I find the A58 lacking in bounce flash, at least compared to the Metz 54. Even with the white bounce card, it is very difficult to get a proper light mix, short of using a diffuser. The Metz has its own front fill flash. This, combined with automatic non-TTL thyristor metering, results in much more pleasant results.

I wish every flash had this option.
 

goonygoogoo

New member
Dave,

Thanks guys. Just got the kit and the battery on the A900 is charging. I'll test out the flash this weekend but it's good to know pre-flash TTL is not biased towards focus points. I focus and recompose a lot.

Regards,
George
 

goonygoogoo

New member
gsking, I was using a non dedicated flash with my D700 and it was working well for me as well. I'll give the 58 a go and see how things turn out. I need to buy a flash adapter to use my thyristor controlled flashes on the A900.

Regards,
George
 

fotografz

Well-known member
I'm using the 58 to shoot weddings ... all types of lighting conditions ... thousands of shots.

Previously used a Nikon D3X and SB900 ... and prior to that a Canon 1DsMKIII and 580EX.

The Sony is just as accurate, and in some cases better (less underexposed shots compared to the Canon).

I have a Metz 54 with Sony module ... I do not agree that it's better ... in fact I think it's worse, very inconsistent results in fast changing lighting.

For quick work compensating flash you can set the A900 "C" button to directly bring up the flash compensation on the LCD. Very fast.

Like all newer flashes with limiters built in, take care when firing bursts in warm weather ... it'll shut down on you just like a SB900 or Canon 380EX will.

Bad part ... no built-in sync port to fire Pocket Wizards for off-camera supplemental flash and no equivalent of a Canon STE2 or Nikon SU800 Commander to do off-camera flash. You have to use a flash in the shoe to fire other flashes, and setting the camera to do that is a huge PITA when shooting in hectic situations.

-Marc
 

goonygoogoo

New member
Marc,

Got to try out the 58 today and it is sweet. I really like the ability to rotate the flash head 90 degrees for portrait shots. ADI is very accurate even with white and black subjects.

I configured the "C" button as you suggested and it does make for very easy compensation. I'm a little disappointed that bounce shots come out darker than I expected, even with very neutral subjects and backgrounds but I can easily compensate.

Do you have a recommended diffuser for the 58?

George
 

fotografz

Well-known member
Marc,

Got to try out the 58 today and it is sweet. I really like the ability to rotate the flash head 90 degrees for portrait shots. ADI is very accurate even with white and black subjects.

I configured the "C" button as you suggested and it does make for very easy compensation. I'm a little disappointed that bounce shots come out darker than I expected, even with very neutral subjects and backgrounds but I can easily compensate.

Do you have a recommended diffuser for the 58?

George
Yes, you can get underexposure using bounce, depending on how you tend to shoot, where the bounce surface is, and what meter pattern you are using.

However, I found that to be true for any flash on any camera ... except the type of flashes like Metz that have a secondary forward flash ... but that only works well when you are closer to the subject. Sometimes secondary flash can cause overexposure of really close subjects if you don't ride the secondary compensation switch or use the clip-on ND filter (which I lose every time I shoot a wedding with one :ROTFL:)

IMO, an overexposed foreground is harder to correct in post than a slight over-all underexposure ... especially with a wedding dress in the scene. A plus 0.07 bounce compensation on the 58 usually works for my typical focal length and distance to subject scenarios and can also depend on which diffuser you are using ... otherwise I ride the "C" button based on "best guess" experience.

When shooting in conditions where flash is important to getting the shots, like at an indoor wedding reception, I use manual on the camera and TTL on the flash. The flash is always set to second shutter.

I tend to "drag" the shutter" ... meaning I set a shutter speed and aperture to open up the ambient lit backgrounds and let the flash figure out the foreground exposure and freeze the action (up to a point, depending on shutter speed).

I usually have 4 different diffusers in my wedding gear bag: the Omni-Bounce type diffuser that usually comes with the flash, A Mila Grid, a LumiQuest bounce diffuser made for Metz (Metz 54-23, which I found holds up better under punishment than the other similar LumiQuest ones I've owned), and a Gary Fong folding diffuser with diffuser dome. I use the Fong diffuser with white translucent dome the most since I tend to shoot rather close up and personal.

-Marc
 
I used to get very good results with this setup. I'm thinking of trying to set up something similar for the a900, but I'm not sure if the on-camera F58 lights the scene when in control mode(I guess I could take 5 minutes and experiment :D ) One of these days I'll get around to digitizing some of the shots I captured with this setup...



For vertical orientation compositions -- bracket was sized to allow the on-camera flash to bounce past the smaller flash:

 

goonygoogoo

New member
Dave, that is a awesome looking setup. Did you modify a stock flash grip to get the heights right or is this a straight custom job?
 
Thanks Goony, it's a one-off, scratch-built. I used it in ratio mode, 2:1 (bounced:direct). As long as I remembered to compensate for very light or very dark subjects, this setup gave me lighting that often looked almost as good as studio lighting(to most people) in a handheld package. The TTL-OTF system on the 7000i/8000i had very good fill/backlight performance and this rig put it over the top for handheld event-type photography IMHO. I think one of the reasons it worked so well is the relatively large/powerful forward-facing 3200i, especially compared to the Metz mentioned above, plus the finer control. Whenever the bounce wasn't quite enough(high/dark ceiling) the 3200i took up the slack; worst case I would get a shot that looked a bit more like typical on-camera flash than the other shots, but still better than with a single forward-facing flash.

These bodies had locator pins in the bottom plate that I utilized to stabilize the bracket:



The threaded hole served dual-duty; I could mount the rig on a tripod if desired but mostly it provided a storage spot to keep the screw from getting lost when the bracket was detached from the camera.



I've done a little reading up and it seems the F42 is the only flash smaller than the F58 that can be controlled in ratio mode, though the very confusing F58 owner manual and Gary Freidman's book seem to disagree on this.

Unless something more like the 3200i shown above is announced at PMA I will probably get the F42 and start figuring something out. The a900 only has a single hole on the base plate that can be used by a locating pin, so I'm thinking along the lines of a second flash bracket that would attach to the left side dovetail of an RRS L-plate(which is on my list to get soon anyway). The basic design layout is going to have to be re-thought if I'm going to use an F42, since it's so much taller -- maybe have the bracket swoop down from the camera body to a handle that would then mount the F42. It may not be possible due to the way the F58 shifts for portrait shooting, though it may be that simply moving the F42 forward would get it out of the way.

I may rent an F42 and see if I can get the behavior that I want before buying another flashgun. I have 6 iISO flashes already not counting the ring flashes, though the i series only work in manual mode, wired or via flash zebra. That's plenty for just about any amateur shooting I can forsee doing in the near future, but if I need to spring for another flash to duplicate the above rig I'll do it. I know it can be done with my second F58 but it's just too big.
 
The better shots that I have taken with this rig are somewhere in the mound of slides and negatives that I am still sorting out to eventually digitize. I can show better images eventually, but I wanted to show something now while the subject is fresh. I do have some shots from a 1999 Xmas party that I had transferred to PhotoCD at the time of development. Unfortunately the camera back was opened mid-roll and it fogged the roll but I think you can still make out the lighting despite the generally horrible quality.

Unfortunately it seems that ratio cannot be used when flashes are cabled together as in the above setup, so wireless would have to be used, or an ND gel on the forward-facing unit. Relying on wireless might present some problems; certainly I would have to avoid covering the receiver on the forward-facing unit. On the plus side, instead of having only 2:1 ratio as an option I could set 4:1, 8:1, etc. Based on the pics below I think 3:1 would be about right.

This first photo shows the "gee-whiz" reaction that I would sometimes get with the setup... especially when everyone else had, if anything, tiny pocket P&S cams:



In this shot you can make out the reflection of the two flashes in the picture on the wall. :)



Three stooges...



Picked up a broad range of tones relatively well...



This one is right at the transition from crappy to unusable in the roll, but enough of it is good that you can see the effectiveness in vertical orientation. I held the camera with the grip at the bottom cradled in my hand so the forward facing flash would be above the lens, with my index finger stabilizing the lens from underneath and my thumb operating the shutter. The tilt may have been at least partly alcohol-induced. :D

 

fotografz

Well-known member
Hmmm, on these examples, the drop shadows to the side of the subject would be a problem for me.

I already get to much of that from the 58 in portrait orientation ... so I turn the camera to place the flash on the opposite side of the prevailing ambient light direction. Other than that you have to get the flash up high enough to drop the shadow behind the subject ... or get it off the camera.

-Marc
 
Yes, for an amateur taking snapshots this is a lot better than a single flashgun and "good enough", from what I've seen of your work I understand why it wouldn't fly for a well-paid wedding gig. :) This was a compromise since I didn't want a big gangly flash arm, I wanted a fairly compact rig. As I mentioned before, the flashes I was using were limited to 2:1 ratio and I think 3:1 or 4:1 would work better for precisely this reason. Could go as high as 16:1, and at that point I think the shadow would fade to obscurity but might not be enough to fill in the "racoon eyes" from bounce. I could try it out easily enough with a couple of F58s, holding the second one. If I like the results I'll take the next step.
 

goonygoogoo

New member
Dave, thanks for posting the samples. The shadows on the side would be a problem for me and this has actually dampened my enthusiasm for the 58 flash as it isn't a solution to replace a flash bracket.

But back to your rig. I actually think that if you modified it where you have a small flash capable of bounce flash, it would work better on the handle mount while using the camera mounted flash facing forward. For verticals, you would set up the flashes as you have depicted in your picture.

Regards,

George
 
Well, to be fair, none of those were taken with the F58. :D

You make a good point though, with the forward-facing flash on-axis the shadows would go straight down and would not be so distracting. When I first put this rig together in the late 80's it was a huge improvement over the flat on-camera flash, I liked most of the results and so did others. It was easy for me to look at the lighting on a subject's face and ignore extraneous shadows, but I understand at your level that's what you get paid the big bucks to AVOID. :)

Thinking back, the better images I've captured with the setup had very dark backgrounds so no shadows. In such cases I think the direct flash coming from an angle looks better than the flat straight-on flash, but then the old gear was pretty limited. There were no TTL ratios other than 1:1 and 2:1. For more careful portrait work I had a rickety umbrella setup that, with a bit of creativity, was another step up.

I have rarely shot groups/events in the past 10 years, and then used mostly a P&S(yes, you have an amateur/hobbyist in your midst :p ) so so I can't discount the possibility that my memory is a bit better than the reality. ;)

What I'm thinking at this point is that the better ratio control with the f58s plus your suggestion might lead to some interesting experiments. First, as I've mentioned, being able to set the direct flash to 1/4, 1/8 or 1/16 relative to the bounce may help a lot. Also with both F58s mounted approximately as shown above, I could try it both ways(swapping the direct/bounce roles) and in portrait mode the side-mounted flash could be rotated almost directly above the lens AND be used as the direct flash. All I really need to test this is a flat plate and a couple of short 1/4-20 screws, I have everything else. I'll have to improvise a subject since my wife only hates one thing more than being photographed -- and that's having her photograph posted in the net. :(
 

gsking

New member
Dave, that's exactly the same result you get much easier with a Metz....without lugging around two flashes. Plus, as you mentioned, since the forward flash is inline with the camera (at least in landscape mode), you don't get an offset shadow.

Marc, I didn't imply the Metz had better exposure control than the 58, but then, I've never had exposure problems with either of them. I just said it was nigh impossible to get proper light balance in bounce mode with the 58 without a diffuser. (I should try one, since I have many. ;) )

I just find the Metz so much easier to use when I'm going to be all-indoors. I leave it in A-mode. The 58 goes outdoors, where it's got more power, better control, easier HSS, and can take my battery pack.
 
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