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645Z firmware update - including turning off dark frames at least!

jagsiva

Active member
With a Phase One digital back e.g. IQ250/IQ260 you just choose "Aerial mode" in camera mode, then the dark frame NR is disabled.
Really? Will have to see if this is the same for the IQ180.

What I find strange is that for exposures in the 1 to 3s range, sometimes there is a dark frame and sometimes there isn't. Somewhat disconcerting when you're doing a 2 or 3 image flat-stitch.

Have others seen this?
 

gerald.d

Well-known member
Really? Will have to see if this is the same for the IQ180.

What I find strange is that for exposures in the 1 to 3s range, sometimes there is a dark frame and sometimes there isn't. Somewhat disconcerting when you're doing a 2 or 3 image flat-stitch.

Have others seen this?
Yup. I've experienced this frequently, and at longer exposures too.

Kind regards,

Gerald
 

jagsiva

Active member
Thanks Gerald. Last time it happened, I was setup in the middle of the Zion canyon with my tripod setup in the Virgin river. I was exhausted and wasn't sure if I was imagining it :)

I'll have to go back and see if there are any differences in the files. Wonder if there is anything in the metadata that tells you if a dark frame was taken or not..

sorry for hijacking this otherwise pleasant post on the 645Z....
 

dougpeterson

Workshop Member
Really? Will have to see if this is the same for the IQ180.

What I find strange is that for exposures in the 1 to 3s range, sometimes there is a dark frame and sometimes there isn't. Somewhat disconcerting when you're doing a 2 or 3 image flat-stitch.

Have others seen this?
Don't be disconcerted! There's some very sophisticated monitoring of the sensor temperature, based on extensive study of the behavior of each sensor/model/firmware-version and a goal of maximum image quality. If the exposure requires a fresh black calibration then it is taken, if it can be reused from the previous capture then it is. Simple as that.
 

GrahamWelland

Subscriber & Workshop Member
With a Phase One digital back e.g. IQ250/IQ260 you just choose "Aerial mode" in camera mode, then the dark frame NR is disabled.
Hmm, that's interesting to know. I've never thought to or tried using that mode with my IQ260. Something to try this weekend!

Update: With my IQ260 fw 5.14.29 (Nov 4 2014) it still performs the dark frame processing even in Aerial mode. :thumbdown:
 
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Update: With my IQ260 fw 5.14.29 (Nov 4 2014) it still performs the dark frame processing even in Aerial mode. :thumbdown:
This is scary. Did you try it on a technical camera or a 645DF+ body? My IQ260 could disable the dark frame NR with the previous version of firmware on a technical camera. I have updated my IQ260 to the latest firmware and I have no backup of the previous firmware! I currently have no camera body to test the latest firmware.

I am now thinking of switching to the IQ250. I am sure with the previous firmware the IQ250 could also disable dark frame NR by using Aerial mode on a technical camera, because I did a 45 minute long exposure test shot with it during a test drive. If Phase One is now preventing us from disabling dark frame NR with the latest firmware and there is no way to downgrade the firmware, then I will switch to the Hasselblad CFV-50C instead.
 

GrahamWelland

Subscriber & Workshop Member
This is scary. Did you try it on a technical camera or a 645DF+ body? My IQ260 could disable the dark frame NR with the previous version of firmware on a technical camera. I have updated my IQ260 to the latest firmware and I have no backup of the previous firmware! I currently have no camera body to test the latest firmware.

I am now thinking of switching to the IQ250. I am sure with the previous firmware the IQ250 could also disable dark frame NR by using Aerial mode on a technical camera, because I did a 45 minute long exposure test shot with it during a test drive. If Phase One is now preventing us from disabling dark frame NR with the latest firmware and there is no way to downgrade the firmware, then I will switch to the Hasselblad CFV-50C instead.
i tried it using my Alpa and in normal exposure latency, aerial mode, dark frame calibration on and off modes. I only shot 5s or so but it definitely counted down after the shot for the dark frame. I didn't try it on a DF+ body although I certainly can later.
 

stephengilbert

Active member
Graham,

I tried with zero latency, and there was no dark frame. 15 seconds, then 20 seconds, both without the dark frame. (IQ 160, latest FW.)

Steve
 

GrahamWelland

Subscriber & Workshop Member
Interesting ... I'll try it again when I'm home later with zero latency.

Back on topic, I was pleased to see one of my local camera stores CameraWorld in Portland is now stocking the 645z (& 645d) and the latest Pentax lenses - what a change from only a few months ago where it was a Pentax desert around here.

Ken: no, I'm still not buying one ...
 

ondebanks

Member
There's nothing for me to quote.
You obviously haven't noticed my avatar :grin: You made some strong technical assertions, and I'd still like to see the basis for them.

I did a long exposure shot of the sun trail (single exposure over 2 hours) and the battery life did not allow the dark frame NR on site.
Nice shot! And an interesting result re. the dark noise of the D800E vs the D4S. The D4S may have one of those sensors optimised for very high ISO snapshots but poor at longer exposures...I had a Kodak DCS720x which was an extreme manifestation of that.

After that I attempted controlled temperature but it could not work perfectly. The distribution of stuck pixels (more than half) are pretty random even at the same temperature.
Are you saying that (a) 50% of the D800E's pixels became "stuck" in your long exposures and (b) entirely different subsets of pixels became stuck in different exposures? That, (b), would be very strange (and not at all what I measure with CCDs...neither photographic or astronomical ones).

Ray
 

Paul2660

Well-known member
I do know that Phase One's official spec on long exposures for the P45+ are, outdoor temps no higher than 69 degrees F and low to moderate humidity. I am not sure on the static electricity but this is CCD vs CMOS.

In my use, the D800e seems to get to a threshold in about 2 minutes to 5 minutes, then the rest of the image seems to stay pretty balanced out. The longest single shot I have taken the D800e to is 30 minutes and that was just playing around, as I normally will only stack at night, max 5 minutes per shot, average 2 min. I always have Long Exposure noise reduction off (which for nikon makes the camera create a dark frame each time).

The CMOS in the D800e does a good job, however it's plagued by the same white dot issue that the D810 had, and Nikon fixed. As I have seen many D800e cameras that don't seem to have the white dot issue, it's clear to me Nikon fixed this issue on the D800 family under the covers, and just forgot to apply the fix to the newer D810. I can also state that the outdoor temperature makes a big difference in the white dots, i.e. 80 degrees or hotter and they will be a pretty big issue. C1 does an excellent job on these spots with the single pixel noise slider, where as LR can not clean them without massive loss of detail in the rest of the image.

With the IQ260, I have only taken mine to 10 and 15 minutes. Both frames at the LE setting of ISO 140. Results were OK, but still not as clean as my P45+ at 45 minutes, so I never really did anymore testing. Each time the back took the dark frame.

I have never tried stacking with the 260, due to the dark frame. If the dark frame can be disabled in Aerial mode in zero latency, I am still not sure it help much since in zero latency the back will get much pretty warm in a much shorter time frame.

Paul
 
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