CFV-16 files green out of camera

[mostlylost]

Files taken in bright direct sun have a distinct green tint out of camera. Adobe ACR requires about a +60 magenta correction, which of course can be baked into the raw conversion so it's pretty much a trivial correction, but still it makes the camera rear display look unpleasant. Not that the screen on the back is any great shakes regardless, but for neatness sake I'd sorta like to get it more or less correct to begin with.

Shutter speed, aperture, cable or no cable, camera model selection in back setup, reloaded latest firmware, reset back defaults, tried two different cameras, a 500 EL/X and a 500 CM, nothing seems to make any difference.

B23 has no idea. Hasselblad Tech Support in NJ is clueless, but then they they said you couldn't get the shot count and run time off the back till I told them how to do it.

There was a similar question asked on this forum several years ago but it was never resolved. Unable to contact the OP on that thread.

 

[ChrisLivsey]

Which body?
Have you tried altering the back's shutter delay setting, not waded through that old thread to see if that was mentioned but I remember reading it?
The manual says:
There can be differences in the amount of time required in preparation (raising the mirror, opening/closing the shutter etc) for digital
capture between various camera models. This corrective feature adjusts the time a little to ensure the image is read out from the sensor. The normal setting is Default and should only be changed if problems are encountered.

They don't specify the problems but I have seen partial capture and weird colours. You particular body may be just mechanically slow or fast and that is having an effect ie the wake up pin may be slow or fast affecting the capture, can you release using a sync cable as you would for a C lens? I understand this also works as a get around for the 1/8th shutter speed settings.

What I do not follow, as a Phase back user (on Hasselblad V& H) is this:
Please note that white balance settings are for your viewing
convenience only. The setting is temporary for preview display
reasons and in no way affects the file which remains neutral
awaiting further processing.

Does this mean you are seeing, within the limitations of the display, a good WB on the preview but not on import? Are you going direct to ACR rather than through Phocus and does Phocus show the same effect?

Also to look at the manual says this about the SWC:

SWC

• Make an SWC setting.
PLEASE NOTE: Due to the mechanical design of the SWC, pressing the exposure release button
too slowly may cause a faulty capture with a magenta cast. Either press the button much more
distinctly or alternatively change the setting from SWC to Flash sync and use the flash sync
cable to connect the lens to the CFV

Which sounds as if the timing is critical to avoid casts and that delay setting is worth experiment.

 

[darr]

... tried two different backs, nothing seems to make any difference.

Sounds like a camera problem.

 

[mostlylost]

Sounds like a camera problem.

Sloppy posting of the original question on my part.

It does sound like a camera problem, primarily because I should have typed "two different bodies" instead of "two different backs". Poor hand/eye/brain coordination

 

[mostlylost]

Which body?


What I do not follow, as a Phase back user (on Hasselblad V& H) is this:
Please note that white balance settings are for your viewing
convenience only. The setting is temporary for preview display
reasons and in no way affects the file which remains neutral
awaiting further processing.

Does this mean you are seeing, within the limitations of the display, a good WB on the preview but not on import? Are you going direct to ACR rather than through Phocus and does Phocus show the same effect?

Also to look at the manual says this about the SWC:

SWC

• Make an SWC setting.
PLEASE NOTE: Due to the mechanical design of the SWC, pressing the exposure release button
too slowly may cause a faulty capture with a magenta cast. Either press the button much more
distinctly or alternatively change the setting from SWC to Flash sync and use the flash sync
cable to connect the lens to the CFV

Which sounds as if the timing is critical to avoid casts and that delay setting is worth experiment.

I think that is probably the new step. I do know that selecting the wrong camera model in the back setup will cause the files to turn magenta due to timing because I set it up wrong when I changed bodies

I read that and I'm "guessing" that they are discussing is creation of the imbedded jpeg which is viewed on the digital back, and the fact that white balance is not baked into the raw but rather "applied" to the raw file and subject to selection in the software. Which of course is just what every other camera maker does with their raw files, they just explain it a tad better.


Color balance is off on the camera screen and off in ACR and also off in Phocus. At least it's consistent.

The reason I contacted Hasselblad is because I was expecting that they have some sort of color calibration routine they can run during service, or perhaps change the tint default setting in the firmware. When you download the service test data file from the back it shows that the tint is set at zero. Perhaps they can change that zero to something else during service.

On the other hand, since I generally include a white balance card in the first shot of a series it is trivial to get correct color, which I find very pleasing from this back, but it would be nice if it looked better on the camera screen and didn't require such a gross correction in processing.

 

[mostlylost]

Well, maybe I found it. The shutter in my 50 Distagon C just packed it in. Shutter doesn't open. At least it didn't get stuck on the body.

 

[Dustbak]

Well, maybe I found it. The shutter in my 50 Distagon C just packed it in. It won't stay cocked. At least it didn't get stuck on the body.

This is often a sync issue (between shutter & back). Sometimes it is the setting on the back but it can also be a less than optimal functioning shutter.

 

[mostlylost]

This is often a sync issue (between shutter & back). Sometimes it is the setting on the back but it can also be a less than optimal functioning shutter.

My best guess at this point is that a package to David Odess is in order.

 

[jdphoto]

I used a 503CW with the CFV, I also had color issues that were a result of pressing the shutter release button slightly, just prior to taking a photograph. If you leave your finger in a "half pressed" mode you can "charge" the back before your ready to take a frame causing RGB anomalies. Make deliberate actions when taking a frame and keep a very light touch on the shutter button prior to shooting. Press firmly when ready.

 

[dave.gt]

Has this issue been resolved????

 

[mostlylost]

Has this issue been resolved????

It has not, although I did replace the 50mm lens that went Tango Uniform. However, nothing changed so apparently that was not a factor.

Hasselblad Tech Service says they do still service the back, but to what extent is unknown. If it's a board replacement issue it might be too expensive to be worthwhile even if the board is available. If it's just an issue of tuning some sort of calibration routine on the back I might spring for that. Since setting a new ACR raw import default effectively cures the issue and largely renders it transparent to the user I'm having a hard time getting too upset. I generally include a white balance somewhere so fine tuning in ACR is quick.

Still, for neatness sake, I'd like to get it corrected.

I also acquired a really good looking example of the 500 c/m to use in addition to the 300 pound 500 ELX . Has a bit of back focus though, so it's about to visit David Odess. Gotta wait for the Social Security check