HVL -F58AM Underexposure Problems

[videoguy]

I just purchased a new F-=58 flash for my A700 (love the 700). I also have a Sigma EF-530 Super flash which works well, but in order to have proper exposures I always have to use the flash and camera in the "M"mode, requiring constant F stop changes. I purchased the F58 thinking that the Sony 700 camera and F58 flash are made for each other so should sync up rather well, enabling to shoot in the P, S ,or A modes resulting with reasonably good exposures. I shoot a lot of events (professionally) and need a camera/flash system which does not require constant F stop changes when I shoot at various distances. Well, I have the same problem with the F58 (except that the exposures are an improvement over the Sigma flash). The pictures are underexposed in all distances over 12 feet (I'm not shooting over 25 ft. usually so I'm well within the flash range). Setting the camera at ADI or TTL makes no difference. Setting the ISO from 200 to 1000 (I would never shoot higher than ISO 400 for flash) makes no difference. Example, the picture will underexpose exactly the same at (S mode) 125th sec, f4.5, ISO 200 or 1000. I can overcome the underexposures by setting the Exposure Comp. +1.3, but should not have to do that.
Does anyone have the same problems and how can I overcome this $500.00 problem ?? I checked and rechecked the manual to ensure that my camera and flash settings are correct. I also called Sony support (they were very helpful) but did not resolve the underexposure problem.
ex video guy.

[David Kilpatrick]

If you are shooting events, you probably do not shoot raw files. Just switch DRO+ Advanced Manual setting to Level 3 and your problems will disappear. If the lenses you are using do not have eight contact pins (ADI, or D type) then you must use Pre-Flash TTL not ADI - set this in the main setup menu.

David

[videoguy]

Hey David !! Thanks for the reply ! I did what you advised and yes it took care of the problem. Not perfect exposures (cannot expect perfect under variable lighting conditions) but good exposures which are far better than what I was getting. I shot tests all around the house in semi-dark and sunlit rooms at various distances and they all looked good on the histogram and in Photoshop. My lens most used is a Sony (Zeiss) 16-80mm, is ADI capable with 8 contacts.
I have two major events to shoot this month (a annual hospital charity Gala and a Community Tea). Both events which will be attended by over 200 people each and will require a lot of flash shooting. Thus your help was very essential.
I'll also look into other suggestions if sent by our readers.
Thanks again,

Dave (ex video guy)

[Johnc]

David - I find your response very interesting.
Is this situation unique to the HVL-F58 or would this also apply to the HVL-F56 on a A700?
Much appreciated.
John

[David Kilpatrick]

It applies to the HVL56AM as well - and to the older 5600HS (D) and 36000HS (D). It only fixed the JPEGs, your raw files may be hopelessly underexposed but DRO+ does a fantastic job of 'developing' them.

This behaviour seems to apply uniquely to flash pix as well. But the results can be noisy or have odd colours if you underexpose the flash shot too much.

David

[videoguy]

David is exactly right. He advised me in this forum and shooting in DRO+ 2 or 3 really brings out the flash. But - I also discovered that noise is greatly increased (see our Forum "Digital Noise (grain) in dark objects with A700" under DSLR System). Sonolta recommended that I try the "Neat Image" software (you can read my reply). I took some pics which I shot using DRO+ 3 (very noisy) and the Pro+ took care of most of it (using the Pro+ advanced mode). I now shoot using less DRO+ but still must under some shooting conditions, and with this software I can clean up the image considerably. Go ahead and download the NI demo and play with it, you'll be impressed.

Videoguy