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09-02-2016, 05:12 AM   #16
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in June, my K3 suddenly started giving me some outrageous color schemes in my photographs. I did all the usual things trying to fix it. What finally fixed it was returning the camera to it's default settings. Of course I had to reenter everything but it has been fine ever since. Only glitch I have ever had with the camera.

09-02-2016, 05:27 AM   #17
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Thanks, panic mode over.

Thought I had a sensor burning out scenario but looks like it is more user error or the lack of understanding.

Historically, I only ever shoot AV, started with the K7 and sort of stuck in that area, learning a little about exposure, depth of field, bokeh and not quite master of it yet.
Quite happy with the results and never progress further skill wise, due to the lack of time and practice. Unfortunately K7 got stolen, upgraded to K3. And with the K3 being a "next gen" leap
from the K7, it's challenging me more, as i dont recall having this kind of problems with the K7.

Anyway back to the problem at hand.
- bunch of white and purple flowers was intentionally stopped down to 1.8, thats the only way i could get some decent exp without blow outs. It's a grey cloudy noon day, and at f4 and upwards would have been whitewashed,
with heavy purple fringing around the white petals. (note the odd single purple flower within the bunch of whites, looks like an odd artefact)

I will do more testing tomorrow and advise whether i can make heads or tails of it, thanks for all your suggestion.

Don't get me wrong, today was the first time that was completely stumped, but otherwise 90% of other times as follows;

Thanks
Ken
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09-02-2016, 05:59 AM   #18
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QuoteOriginally posted by kenkk Quote
*snip*

- bunch of white and purple flowers was intentionally stopped down to 1.8, thats the only way i could get some decent exp without blow outs. It's a grey cloudy noon day, and at f4 and upwards would have been whitewashed,
with heavy purple fringing around the white petals. (note the odd single purple flower within the bunch of whites, looks like an odd artefact)

*snip*

Thanks
Ken
You don't "stop down to 1.8", you "leave wide open at 1.8"... remember that aperture numbers are f/n, so f/1.8 is wide open and f/22, f/32 or whatever is fully stopped down.
To let less light enter you have to stop down, i.e. go 1.8 -> 2.8 -> 4 or whatever, so the whitewash effect at f/4 is actually due to something else (camera compensating with shutter speed, autoISO, whatever, trying to compensate).

If I would have to bet, I would put 2c on a failed aperture mechanism/linkage/lever/something in the aperture control chain, camera side (since you get that with all lenses).
09-02-2016, 06:31 AM   #19
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QuoteOriginally posted by BigMackCam Quote
Just to show what I mean regarding over-exposure... see the attached. Exactly the same photo, but with different exposure levels...
Exactly. Its more of color exposure for the color red or pin in the original image in context. Sony sensors and (I am seeing most sensors in general) tend to saturate more on reds and pinks without too much pumped in saturation. I have seen this behaviour plenty of times and I change out from Vibrant mode to more like muted something that does not pump up the colors. That gives me better JPEGs in situations like these. Ofcourse it DNM as much for RAW files.

09-02-2016, 06:44 AM   #20
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QuoteOriginally posted by kenkk Quote
bunch of white and purple flowers was intentionally stopped down to 1.8, thats the only way i could get some decent exp without blow outs. It's a grey cloudy noon day, and at f4 and upwards would have been whitewashed
I think maybe you don't understand what the aperture settings actually mean. The smaller the number, the bigger the opening, the more light gets in, the brighter the image is, and the less depth of field it has.

Put it in manual mode, with the shutter to 1/125 and ISO at 100, focus on a yardstick or something similar thats at an angle away from you, and take shots at f/1.8, 4, 8, and 16 and you'll see each shot is progressively darker and has more of the yardstick in focus.
09-02-2016, 07:26 AM   #21
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K3 exposure issues

I had the same problem on my K3 2 months ago. I reset the camera to default settings and all is fine.
09-02-2016, 07:54 AM   #22
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There are probably some exposure issues at work here, but when I saw the first set of photos my immediate thought was, "inadvertent use of custom image settings". The "-->" button on the K-3's 4-way controller turns on the custom image menu. This is easy to do accidentally with the heel of the thumb. A couple more accidental presses and you are in wonderland with x-process or some other strange effect.


Steve
09-02-2016, 05:38 PM   #23
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This morning's shots.

Morning all,

I have not touched any settings from yesterday, tried the 31 then 77, same effect.

Checked the following;
-vibrant to natural, nil effect (also check individual Parameter Adj, all set neutral 0)
-AWB to daylight to cloudy, nil effect.
-no ev settings.
-multi focal to spot, nil effect.
-Tried TAv, set at F5.0, started at 1/250, 1/400. to 1/6400, similar affect as AV, higher speed darkens picture, but blown lighter highlights.
-checked all on camera mount pins (altho all were dimple except 1 flat)

Will check menu settings and set ups (as per forum's preferred K3 setting).
Failing these i will factory default reset.

Cheers
ken

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09-02-2016, 06:37 PM   #24
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I think that confirms its definitely an aperture lever issue.
09-02-2016, 06:42 PM   #25
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It looks like your lens isn't stopping down. You'll get good exposures when you shoot wide open, but when you stop down, the camera will do the math and increase the exposure time. When you take the picture the aperture in the lens won't close down and you get an over-exposure. Unless I'm missing something, that appears to be what is happening.

The question is: Is it your lens or your camera that has a problem? Your shots from the 16-85mm lens look okay even stopped down.
09-02-2016, 08:13 PM   #26
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From what i can tell the 16-85 is not affected.

Whilst I sort my upload photo limits, i have reset default settings at the end of C24 settings.

Mounted the 77 and the issues are still present.
Set the camera to fully auto mode Green rectangle, and still same issue.

I will investigate the aperture lever issue.

Tks and Rgds
09-02-2016, 08:51 PM   #27
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Two things to check...

Aperture control on camera:
  • Lens on camera
  • M mode
  • Shutter speed at 2s
  • Aperture at minimum for the lens
  • Release shutter five times while looking into the front of the lens
  • Repeat for each full aperture stop including wide open
The iris should open the same amount for each of the five repetitions and should open appropriately.

Lens aperture functionality:
  • Lens off camera
  • Aperture ring at smallest setting
  • Looking into rear of lens, flick the aperture actuator with your finger. The motion should be snappy and without sticking or hesitation from the set aperture to wide open.
  • Repeat for for each full stop until wide open
For lenses lacking an aperture ring, just do a careful evaluation at narrowest setting (default when not mounted to the body).


Steve

Last edited by stevebrot; 09-02-2016 at 09:23 PM.
09-02-2016, 09:59 PM   #28
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QuoteOriginally posted by stevebrot Quote
Two things to check...

Aperture control on camera:
  • Lens on camera
  • M mode
  • Shutter speed at 2s
  • Aperture at minimum for the lens
  • Release shutter five times while looking into the front of the lens
  • Repeat for each full aperture stop including wide open
The iris should open the same amount for each of the five repetitions and should open appropriately.

Lens aperture functionality:
  • Lens off camera
  • Aperture ring at smallest setting
  • Looking into rear of lens, flick the aperture actuator with your finger. The motion should be snappy and without sticking or hesitation from the set aperture to wide open.
  • Repeat for for each full stop until wide open
For lenses lacking an aperture ring, just do a careful evaluation at narrowest setting (default when not mounted to the body).


Steve
Hi Steve,
Thanks, have done a few on the few lenses i have and nothing unusual that i can see.
Tried the DA 12-24 and looks like zooms are not affected, ran through once again the 40,100WR same problems.

Finding it odd, usually shooting AV, my main concern is Aperture priority, sharpness across the picture, bokeh effect etc.. and the shutter speed is automatic and never take notice of it, esp during outdoor daylight shots.
Unless low light, utilising faster glass, monitoring the shutter speed to avoid the shakes. Other than that i usually let the camera do the shutter speed.

Regards
09-02-2016, 10:43 PM   #29
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QuoteOriginally posted by kenkk Quote
Hi Steve,
Thanks, have done a few on the few lenses i have and nothing unusual that i can see.
Tried the DA 12-24 and looks like zooms are not affected, ran through once again the 40,100WR same problems.
Check the body aperture control. The example photos you shared indicate that the lens is not stopping down the aperture set and recorded in the EXIF. The only ones with correct exposure were those taken with the lens wide open (EV was the same for all in the series). This is easily assessed visually by looking into the front of the lens during an exposure cycle. If you can't see the aperture blades stop down, they are not stopping down.


Steve
09-02-2016, 11:11 PM   #30
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^^^ Another easy test would be to set the aperture to something small like f/16 or f/22, then - while looking through the viewfinder - use DOF preview... It should be obvious if the aperture is closing and opening....
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