Lee,

thanks for giving the hint to the API. I wasn't aware that something like that exists.
I had a quick read through and the description seems to be fairly straight forward. Don't know if I find the time to give it a go anytime soon...

I'm sure that there are other forum members who would know how to do it...

Prieni

Stefan, tell me about it
I did understand what you meant from your earlier post. To get consistent banding over the whole image, though, the amplifier of one (or more) lanes has to receive an interference that consistently affects the amplification. While that is not impossible (I don't know much about the innards of the camera electronics) I would think it is quite unlikely.

Thanks Matt, I wasn't aware that the "Geometric NR" would help with such problems. I certainly will give it a try.
And yes, I don't think it is serious either. If I wouldn't do CA correction at 400% as standard I wouldn't have noticed at all. And when printing I would have blamed my ageing ink jet printer...

Prieni

Welcome to the forum Steve!

From what you wrote there I think you came to the right forum. A Critical-i certainly isn't lost on the forum members.

Prieni

Edit for grammatical reasons

Nice series of shots.
#1 I think I like least, though I cannot really put my finger on what I don't like. I would try to darken the upper (distant) parts a bit.

#2 is a good shot. Especially like the light coming from the front and showing the drops on the blades. It also gives the spikes an 'aura'. I think I would like it more a touch warmer, more like #3.

#3 lovely shot, excellent. The only thing I would change is clone out the white area upper left.

#4 I'm quite tired of dragonfly shots generally (mostly down to PPG, I guess), but I do like your shot here even though the background could be a little less busy.

Thanks for showing,
Prieni

Thank you all for ideas and suggestions.

John,
the scene is very similar for both shots and the flare is there in both shots. So why should it influence one but not the other?

Peter, Stefan,
as far as I am aware the image is captured first (in full) and after the shutter is closed the readout starts. So I don't think this banding is from movement of the sensor while capturing the image (though I expect when SR hasn't locked on then the sensor IS moving during capture).
The suggestion for a firmware update does sound reasonable.

Even with a parallel readout system (and judging by the frame rate it couldn't be a very effective system in the K20 if it has one) I wouldn't understand why this difference should only occur when SR hasn't locked on.

George, Gwyn,
you can see it at 100% if you try hard (i.e. you better know before what to watch out for). So this is a 'no' on George's question (if only just).

And this is why I am not overly concerned. Having said that, if I would like to print this beautiful photo at 50 x 75 cm I guess that it would matter. As it is not such a great shot (and I have the second one without this 'feature') it doesn't matter at all.

I would like to find out what the reason for this banding could be to avoid it in future (it could be the 'once in a lifetime' shot that would be ruined by it (or by some hundreds of other things...)).

If I can pin the reason down I'll let you know.

Cheers,
Prieni

Peter,

looking at the EXIF that seems to be the (only) difference between the two shots. When taking the first shot SR had not stabilized after 0.42 s; on the second one I gave the camera 1.2 s and stabilization was effective. So this might be the reason, although I don't quite understand why that would cause the banding.

Now you're hurting me, not trusting my description of the banding
It is possible that I didn't describe the banding correctly, just to make sure that we talk about the same thing I have added a 200 percent crop (upscaled in Photoshop using 'bicubic'):
[IMG]http://i156.photobucket.com/albums/t5/Prieni/_RDP4340crop200.jpg[/IMG]
I think that this shows exactly what I described (at least it does look exactly as what I wanted to convey in words :wink.

Stefan: The camera temperature was 16 degC in both cases (and I doubt that it would change very much in 8 seconds anyway).

So for the moment I will blame it on the SR not being ready. Have to dig out other shots where SR was not ready and see if that showed the same thing...

Cheers,
Prieni

Welcome to the forum, Offertonhatter!
You came to the right place for tips and insights.
This forum is not strictly for users in the UK, there are quite a few members from far away places.

Prieni

On the weekend I finally found time to take a stroll in the autumn landscape. At the shore I took this photo (with the Sigma 105 macro, EXIF intact):
[IMG]http://i156.photobucket.com/albums/t5/Prieni/_RDP4340pu.jpg[/IMG]

8 seconds later I took a second shot with same settings:
[IMG]http://i156.photobucket.com/albums/t5/Prieni/_RDP4341pu.jpg[/IMG]

Back home I started converting the day's bounty with SilkyPix. One step of the routine is to correct CA and for that I usually zoom to 400% in one of the corners. When working on the first shot I noticed regular vertical lines repeating, one line with lighter pixels, one line with darker pixels etc. This pattern filled the whole image. Here's a 100% crop of the lower left corner of the first shot:
[IMG]http://i156.photobucket.com/albums/t5/Prieni/_RDP4340crop.jpg[/IMG]

The same for the latter shot:
[IMG]http://i156.photobucket.com/albums/t5/Prieni/_RDP4341crop.jpg[/IMG]

So two questions:
1. What the heck is going on there?
2. Should I put this thread up over on depressing review and stop the time until the first one bites?

Ok, question 2 is not that serious.
I'm not overly concerned as it hasn't happened for the last 4000+ shots. But something similar happened when the camera was new (see thread here)

Mike, great shot and well deserving of getting in the PPG.

Well done!

Prieni

Welcome Istvan,

you certainly entered the forum in style. Good to see that more young folk is joining the forum. That will give us old-timers a run for our money.

Speaking of old-timers: I'm 44 years old (some forum members will say I'm barely grown up), a physicist by training and work as an engineer/scientist developing chemical sensors for oceanography.

I ventured into Pentax DSLR's when the *istD came out. I had a Ricoh SLR before and with the *istD I was able to use some of the lenses. The lenses from that time have all retired now.

My latest support for the ailing photo industry was a K20 in March and a DA* 16-50 this month. The K20 certainly has dropped in value since March but not as much as some companies shares...

Prieni