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IQ3 100MP long exposure issue - shadow filled with red color cast

For case and control purposes, here is another test with an IQ250, with exactly the same test conditions as the IQ3 100MP above:

3.JPG
 

AreBee

Member
voidshatter,

Shoot an image at 30min with Singh-Ray 15-stop Mor-Slo (95mm thin ring). Bang!
Perhaps the adverse effect is related to infrared light, given the strength of ND filter in conjunction with long exposure.
 
voidshatter,



Perhaps the adverse effect is related to infrared light, given the strength of ND filter in conjunction with long exposure.
a) My friend also gets the red cast with Schneider IRND;

b) Four units get a red darkframe with the lens cap on, and I don't think the lens cap has anything to do with infrared light;

c) The IQ250 works fine under the same conditions.
 
Update:

Another test setup:

a) Power on and couple with 40mm HR without shift;
b) Set camera mode to aerial and zero latency;
c) Shoot an image at 1/60s;
d) Shoot LCC;
e) Shoot an image at 1/15s without ND filter;
f) Shoot an image at 2min with Lee Big Stopper (100mm x 100mm square);
g) Shoot an image at 30min with Singh-Ray 15-stop Mor-Slo (100mm x 100mm square). Bang!

IQ3 100MP demo unit (SN: IG01112?) with firmware 4.03.2:

4.JPG

And again with an IQ250 with the same setup above for comparison:

5.JPG
 
I'm now playing with the XF+ body. As a first time user I still need to read the manual :loco: I'll try to catch the light with the same conditions before the sun goes down.
 

Pradeep

Member
I don't have a dog in this fight. Never done long exposures beyond 5 minutes or so.

Just wondering, is there a particular time cut off where the red cast appears? Would you be able to take exposures at say 5 minute intervals to see exactly how long it takes? Just curious, it may be to do with the sensor heating up and causing the problem after a certain length of time.
 

algrove

Well-known member
I have gone to 16 minutes plus 16 of black frame with no problems. What is the big deal here, just turn off aerial and bit the bullet of double time like most photograhers do.
 
I don't have a dog in this fight. Never done long exposures beyond 5 minutes or so.

Just wondering, is there a particular time cut off where the red cast appears? Would you be able to take exposures at say 5 minute intervals to see exactly how long it takes? Just curious, it may be to do with the sensor heating up and causing the problem after a certain length of time.
Sure I'll add that to my test list :)

I have gone to 16 minutes plus 16 of black frame with no problems. What is the big deal here, just turn off aerial and bit the bullet of double time like most photograhers do.
The big deal is that you miss opportunities in real world usage e.g. sunset/sunrise. You also get only half the success chance of the IQ250/D810 etc. You also have half effective battery life. Shooting darkframe in 2016 really? :shocked: No thanks, not for an expensive camera like this.
 
Is there some reason that this conversation isn't with Phase?

I once had a problem with my IQ 260. I called the dealer.
It would take several weeks if a unit is sent back to Phase One. If we can isolate the problem and let Phase One reproduce it with their own units then it saves us time sending our units to Phase One. Also it would be helpful to make the public aware of the issue so that Phase One can deal with it actively. The down side is that the current owners will not be happy with it.

The IQ260 had the corner issues during long exposure. Did you dealer resolve it for you? I doubt it. I'll put my money in it that even if you sent your IQ260 back to Phase One they could not fix it for you.
 

dchew

Well-known member
Yunli,
Would you please provide a screen shot for us of the image with the red cast (CF006566) as it came out of the camera with no adjustments? I'm trying to compare it with my results.

Thank you,
Dave
 
Yunli,
Would you please provide a screen shot for us of the image with the red cast (CF006566) as it came out of the camera with no adjustments? I'm trying to compare it with my results.

Thank you,
Dave
IQ3 100MP aerial mode + zero latency + not first image since power on + 30min long exposure + without any adjustment (and without LCC) straight out of the camera:

Left: 23HR; Right: 40HR

6.JPG
 

dchew

Well-known member
Also, as has been previously discussed, you are forcing the back to use a 1/60 sec dark frame for a long exposure. Please try taking an initial exposure of relevant exposure time. Knowing how the back uses the dark frame that would make a lot of sense, and would not create "missed opportunity" issues in the field.

Dave
 

dchew

Well-known member
IQ3 100MP aerial mode + zero latency + not first image since power on + 30min long exposure + without any adjustment (and without LCC) straight out of the camera:

Left: 23HR; Right: 40HR
Thank you. That makes more sense especially since you are using a very short exposure dark frame.
 
Also, as has been previously discussed, you are forcing the back to use a 1/60 sec dark frame for a long exposure. Please try taking an initial exposure of relevant exposure time. Knowing how the back uses the dark frame that would make a lot of sense, and would not create "missed opportunity" issues in the field.

Dave
Sure I'll add that to my test list.

Yes it could miss opportunity because if you shoot a preliminary darkframe beforehand, you may run into the following issues:

a) The cloud is moving faster / slower than you expected and you need to shorten / lengthen your exposure time and that is then different from your preliminary darkframe;

b) The glow of the sunset / sunrise comes sooner / later than you expect and then you have to terminate the preliminary darkframe / keep your camera on to waste extra battery life as well as accumulating extra heat;

c) Swapping battery in the field means game over.

There is no good excuse when the IQ250 and the D810 can do the job without such issues.
 

dchew

Well-known member
c) Swapping battery in the field means game over.
Naw, it just means a new inning. You have to wait for the pitcher to warm up again.
;)


There is no good excuse when the IQ250 and the D810 can do the job without such issues.
Sure there is. The 3100 has a lot less field time vs the sensor in those other two products. Well, maybe it is not an excuse, but it could be a good reason.

Dave
 

kdphotography

Well-known member
Maybe Doug Peterson can give you his $.02. (which I bet we share the same thinking here)

Imho, the best course of action is to go through your dealer and work with Phase One. There are way too many variables to deal with---and I do trust Phase One has the facilities and know-how to resolve a situation. It maybe a firmware issue, C1 Pro post-processing issue, etc. Dunno. Or perhaps, it may be just one of those things where the IQ3 100MP isn't the best camera choice for this particular limited situation.

Have you talked with Tech support at your dealer? Has the tech done any trouble shooting for you? Has the tech contacted Denmark? Have you contacted Phase One?

With the few issues that I've had over the past ten+ years, this has always worked well for me.

Ken
 
Naw, it just means a new inning. You have to wait for the pitcher to warm up again.
;)

Sure there is. The 3100 has a lot less field time vs the sensor in those other two products. Well, maybe it is not an excuse, but it could be a good reason.

Dave
Well I definitely don't want to shoot a darkframe when I swap battery while the cloud looks beautiful :p

The D800 and the D800E were the first camera utilizing the Sony IMX094 sensor and with 1.0.0 firmware out of factory they could do excellent long exposure without such limitations.

Your point on the preliminary darkframe makes sense and may be the key to the red cast for the IQ3 100MP and maybe the duration difference between the preliminary darkframe and the lightframe plays a significant role here. Let's denote it as delta_T. I'll try to test for delta_T=0min, 5min, 10min ... 30min and see what happens. Hopefully this helps Phase One fix this issue.
 
Yes and before doing that I still would like to see a XF/DF image from that back. As my guess is still rech camera problem.
This is for you Chris - a test with the XF+ camera body and a Schneider 55mm f/2.8 LS.

First of all, I set the digital back to aerial mode and zero latency and then attached it to the XF+ camera body. The digital back just doesn't synchronize correctly with the camera body for long exposure. I had to detach the digital back, set it to normal mode and normal latency and then reattach it to the XF+ camera body for long exposure, which means for each lightframe there is a compulsory darkframe countdown. (Note that I have closed the viewfinder to block light leakage.)

1/25s: no ND filter
2min: Lee Big Stopper (100mm x 100mm square)
30min: Singh-Ray 15-stop Mor-Slo (100mm x 100mm square)

Here are the results with white balance correction without pushing shadow:

7.JPG

With +100 shadow push there is a slight red cast in the shadow but not that obvious as seen previous tests:

8.JPG

100% crop of shadow confirms red noise:

9.JPG
 
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