K-5: What is up with this multiple image?

Started Nov 21, 2010 | Discussions
psu28k Regular Member • Posts: 357
K-5: What is up with this multiple image?

1/20s f/4 ISO6400.
Why does the car have multiple images?

 psu28k's gear list:psu28k's gear list
Sony Mavica FD-83 Pentax Optio W80 Pentax K10D Pentax K-5 Pentax smc DA 15mm F4 ED AL Limited +6 more
Brad99 Veteran Member • Posts: 3,145
Re: K-5: What is up with this multiple image?

My guess is that it's because the car is illuminated by sodium lighting that is flickering at twice the HZ of your local mains supply, so if that's 50Hz it will flicker at 100Hz. Your 1/20s shutter will capture 5 cycles worth of illumination which is the number of multiple images actually captured.

MightyMike Forum Pro • Posts: 39,020
Re: K-5: What is up with this multiple image?

an interesting theory however it is clearly the SR, since you can't set the SR to panning mode then its better to turn it off when panning if you don't want this effect... the SR is trying to compensate for the panning and is hitting its limit so the sensor is shifting back and forth during the exposure giving multiple images
--
Mike from Canada

'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote :)'

http://www.airliners.net/search/photo.search?sort_order=views%20DESC&first_this_page=0&page_limit=180&&emailsearch=mighty_mike88%40hotmail.com&thumbnails=

Wallace Ross
Wallace Ross Senior Member • Posts: 2,128
Re: K-5: What is up with this multiple image?

I think with these ISO's you may be going into territory that hasn't been fully explored yet. The car may be illuminated by the street lighting that is cycling at 120Hz resulting in the vehical being lit and unlit multiple times. Notice how the constatly lit DC lighting of the vehical is not effected but the reflectors are.

Wallace Ross
Wallace Ross Senior Member • Posts: 2,128
Nope have a look at the background.

Nothing to do with anything spicific to the camera just the fact that it was possible to get an image because of the ISO. A film camera would have done the same thing.

bricko Regular Member • Posts: 296
Re: K-5: What is up with this multiple image?

Were you panning? The house is not blurred...if he was panning the house should be blurred rather than the car? Is it just that the car is moving and getting normal movement blur since its perpendicular to sensor plane.

Leuf Senior Member • Posts: 1,131
Re: K-5: What is up with this multiple image?

If this was a panning shot then the rest of the scene would be blurred, since the foreground is sharp surely the camera was still.

MightyMike Forum Pro • Posts: 39,020
Re: Nope have a look at the background.

hmmm... ok yes if the effect were reversed then i'd be right, if the background had the issue but the subject being panned on didn't... ok so it ust be some other reason
--
Mike from Canada

'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote :)'

http://www.airliners.net/search/photo.search?sort_order=views%20DESC&first_this_page=0&page_limit=180&&emailsearch=mighty_mike88%40hotmail.com&thumbnails=

DrewE Senior Member • Posts: 2,053
Re: K-5: What is up with this multiple image?

MightyMike wrote:

an interesting theory however it is clearly the SR, since you can't set the SR to panning mode then its better to turn it off when panning if you don't want this effect... the SR is trying to compensate for the panning and is hitting its limit so the sensor is shifting back and forth during the exposure giving multiple images

The background is nice and sharp (which suggests that the shot was not panned--or if it was panned, that the SR system did a superb job of eliminating the motion without running out of room). Also, only the parts of the car illuminated by the streetlight shows the multiple image, while the headlights and taillights (for example) are nice and continuous. The AC streetlight theory sounds right to me.

I've seen similar effects on long night shots myself, although more often in a situation reversed from this one: when shooting out a car window, streetlights close to the vehicle appear multiple times due to the car's movement relative to them, while distant ones are sharp.

Edited -- I'm not the only one to disagree, and I originally worded this rather more strongly than I should have. Sorry.
--
--DrewE

 DrewE's gear list:DrewE's gear list
Pentax K10D Pentax K-5 Pentax smc DA 18-55mm F3.5-5.6 AL Pentax smc DA 40mm F2.8 Limited Voigtlander 58mm F1.4 Nokton SL II +3 more
MightyMike Forum Pro • Posts: 39,020
Re: K-5: What is up with this multiple image?

yes i goofed
--
Mike from Canada

'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote :)'

http://www.airliners.net/search/photo.search?sort_order=views%20DESC&first_this_page=0&page_limit=180&&emailsearch=mighty_mike88%40hotmail.com&thumbnails=

MightyMike Forum Pro • Posts: 39,020
Re: K-5: What is up with this multiple image?

ok already i said i goofed
--
Mike from Canada

'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote :)'

http://www.airliners.net/search/photo.search?sort_order=views%20DESC&first_this_page=0&page_limit=180&&emailsearch=mighty_mike88%40hotmail.com&thumbnails=

MightyMike Forum Pro • Posts: 39,020
Re: K-5: What is up with this multiple image?

yes lets call it sarcasm, it sounds better then making a mistake, not paying close enough attention to the image, saw the effect and related it to something i recognized but had it reversed
--
Mike from Canada

'I like to think so far outside the box that it would require a telephoto lens just to see the box!' ~ 'My Quote :)'

http://www.airliners.net/search/photo.search?sort_order=views%20DESC&first_this_page=0&page_limit=180&&emailsearch=mighty_mike88%40hotmail.com&thumbnails=

OP psu28k Regular Member • Posts: 357
Re: K-5: What is up with this multiple image?

I like this theory. Thank you.

 psu28k's gear list:psu28k's gear list
Sony Mavica FD-83 Pentax Optio W80 Pentax K10D Pentax K-5 Pentax smc DA 15mm F4 ED AL Limited +6 more
bricko Regular Member • Posts: 296
Re: K-5: What is up with this multiple image?

Have you seen it anywhere else? If the site is close by...try it again. Or at another like spot with different type of light. Set the shutter as before 1/20 sec. etc.

As noted above, the lights on the car streak are continuous.

onesidedcoin Regular Member • Posts: 404
Nothing New

I have gotten the same effect with shooting the swing of a base ball bat with a k20 with the right shutter speed. Is a moving object.
--
Dave

ozdean
ozdean Forum Pro • Posts: 24,994
Re: K-5: What is up with this multiple image?

Yep I think you have it Brad - I'll go with that.
--
Regards Dean - Capturing Creation

 ozdean's gear list:ozdean's gear list
Pentax MX-1 Pentax K-5 IIs Pentax K-50 Pentax K-70 Pentax smc DA 15mm F4 ED AL Limited +12 more
zxaar Veteran Member • Posts: 4,345
Re: K-5: What is up with this multiple image?

Wallace Ross wrote:

I think with these ISO's you may be going into territory that hasn't been fully explored yet. The car may be illuminated by the street lighting that is cycling at 120Hz resulting in the vehical being lit and unlit multiple times. Notice how the constatly lit DC lighting of the vehical is not effected but the reflectors are.

makes sense to me.

-- hide signature --

::> I make spelling mistakes. May Dog forgive me for this.

John Venables Senior Member • Posts: 1,137
Re: K-5: What is up with this multiple image?

I agree

I found an example taken with my K10d

Shutter Speed 1/20s
This is in Melbourne so mains frequency is 50Hz

-- hide signature --

John V
K10D Tamron90DImacro Zenitar Tamron 200-500(screw mount)

ozdean
ozdean Forum Pro • Posts: 24,994
Re: K-5: What is up with this multiple image?

We could calculate how fast he was going John - better not tell the officers , the state government will have a speed trap rigged at every light post!
--
Regards Dean - Capturing Creation

 ozdean's gear list:ozdean's gear list
Pentax MX-1 Pentax K-5 IIs Pentax K-50 Pentax K-70 Pentax smc DA 15mm F4 ED AL Limited +12 more
Younes Senior Member • Posts: 1,597
Re: K-5: What is up with this multiple image?

Both shots were taken at 1/20 s. For me, there is no problem at all. How can you expect to have a still image of a moving car that you shoot at 1/20s? The blurr is motion blurr. That's it. If you don't want it, you increase the ISO till you can get proper exposure with a decent shutter speed ( 1/200s or more).

-- hide signature --

Younes ( Paris, FR)
K100D,K10D,D40 + lenses

Keyboard shortcuts:
FForum MMy threads