Interval shooting

sjovolde · 12-06-2015, 06:57 PM

Hi
I set up my K3 to do an interval shoot last night. I was using my 28 2.8M lens and set the camera to take 90 images 20 seconds long, on interval composite with a bright setting. What I'm wondering is what caused the concentric cirlces in the center of the shot. any ideas would be helpful.

Thank You
Evan

Attached Images

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**Quartermaster James** · 12-06-2015, 07:22 PM

Funny you should ask that. The only time that I've had that happen was with shooting the aurora too!

SKYGZR · 12-06-2015, 08:10 PM

Looks like the focusing screen???

C_Jones · 12-06-2015, 08:12 PM

I definitely do not know if this is the answer, but factors to consider may be SR being on, NR being on, no GPS unit to handle movement/trailing, or just a result of the composite creating something like that out of coincidence when handling the composite data.

I am not that much of an expert in this area, but if you tried similar tests using maybe a single image, a set of 15 composite, and a set of 30 images composite, and see if you get similar "circles" as you did in the 90 image composite, that might tell you if it is a recurring factor.

**tduell** · 12-06-2015, 08:16 PM

I see a similar story here <http://www.dpreview.com/forums/thread/625189?page=3>.

Cheers,
Terry

sjovolde · 12-06-2015, 08:23 PM

Thanks for the ideas. I had the camera set to keep all the previous images and the pattern shows up on all of them, it gets more pronounced as the shoot progresses.
Shake reduction was turned off, and as far as I know the noise reduction has no effect on raw files unless I'm wrong.
If its the focusing screen, why would it show up.
I'm wondering it it's some sort of reflection inside the lens. Quartermaster James I was wondering what lens you used. The exif data just says 15 mm. Maybe it's a problem with using older M series lenses for this type of photography.

Thank you
Evan

**colonel00** · 12-06-2015, 08:37 PM

Nothing to really contribute but subscribing as this is very interesting...and, it was aliens

Actually, a couple observations. First, to the OP, it looks like you have a couple bumps of the camera at the beginning and end. Not that this is the cause but just curious if you noticed them. QMJ, you might have some dust on your sensor as there is a reoccurring dark spot.

Anyway, reading that linked thread, I also have to wonder if it is some moire effect since you are both using the K-3. I also see mention that this occurs when using a filter but I don't think eighter of you mentioned using a filter.

Last edited by colonel00; 12-06-2015 at 08:43 PM.

**Quartermaster James** · 12-06-2015, 08:42 PM

Originally posted by sjovolde

Thanks for the ideas. I had the camera set to keep all the previous images and the pattern shows up on all of them, it gets more pronounced as the shoot progresses.
Shake reduction was turned off, and as far as I know the noise reduction has no effect on raw files unless I'm wrong.
If its the focusing screen, why would it show up.
I'm wondering it it's some sort of reflection inside the lens. Quartermaster James I was wondering what lens you used. The exif data just says 15 mm. Maybe it's a problem with using older M series lenses for this type of photography.

Thank you
Evan

These were taken with the Sigma 10-20 F3.5

C_Jones · 12-06-2015, 08:42 PM

It looks like there was quite a bit of mass movement differential in the center and surrounding center area, whereas the light trails and the lower and near bottom area seem to have good sharpness consistency. The trails seem to have taken the attention of the focus somewhat away from where the "circle" occurred.

**Quartermaster James** · 12-06-2015, 08:43 PM

Originally posted by tduell

I see a similar story here <http://www.dpreview.com/forums/thread/625189?page=3>.

Cheers,
Terry

Intrigomon. I did have a protective filter on at the time.

C_Jones · 12-06-2015, 08:51 PM - **1 Like**

I want to mention metering setting as one more thing, though I am not sure completely if that may be a possible contributor. As Quartermaster James and colonel00 mentioned, a filter or anything else covering the lens could easily cause a spherical "circle" to be created.

sjovolde · 12-06-2015, 08:51 PM - **1 Like**

Intrigomon, Quatermaster James. I was also using a UV filter. If I get a chance in the next day or so I'm going to try again with the same setup and remove the UV filter to see if it makes a difference. Would be an easy fix if that does it.

Thank you everyone for the information. This forum always amazes me how fast you can get answers to your questions.
Colonel 00 as far as the bumps go, I was shooting on my deck, and was wandering around for the half hour it took to shoot this. Next time I'll have to try stand still.

Evan

DeadJohn · 12-06-2015, 09:05 PM

That looks like Newton's Rings. I've never noticed it with my gear, but astrophotography forums have discussions of the problem. Also see https://en.wikipedia.org/wiki/Newton's_rings

Does interval composite save each subframe in addition to the final composite? If yes, do you see the rings in the subframes?

**Quartermaster James** · 12-06-2015, 09:07 PM

Originally posted by C_Jones

As Quartermaster James and colonel00 mentioned, a filter or anything else covering the lens could easily cause a spherical "circle" to be created.

I'm not sure I want to be pointing a non-WR lens upward into snowfall without one though!

DeadJohn · 12-06-2015, 09:07 PM - **1 Like**

Originally posted by sjovolde

SNIP...UV filter...SNIP

Flat filter plus curved front glass increases the risk of light interference patterns. Sounds more and more like Newton's Rings.

12-06-2015, 08:51 PM - 1 Like	#11
C_Jones Pentaxian Join Date: Sep 2012 Location: NY Photos: Gallery \| Albums Posts: 6,084	I want to mention metering setting as one more thing, though I am not sure completely if that may be a possible contributor. As Quartermaster James and colonel00 mentioned, a filter or anything else covering the lens could easily cause a spherical "circle" to be created. Last edited by C_Jones; 12-06-2015 at 09:06 PM.

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12-06-2015, 08:10 PM	#3
SKYGZR Senior Member Join Date: Dec 2014 Location: Milky Way Galaxy, Planet Earth, Speeding towards the Virgo Supercluster Photos: Gallery \| Albums Posts: 156	Looks like the focusing screen???

12-06-2015, 08:12 PM	#4
C_Jones Pentaxian Join Date: Sep 2012 Location: NY Photos: Gallery \| Albums Posts: 6,084	I definitely do not know if this is the answer, but factors to consider may be SR being on, NR being on, no GPS unit to handle movement/trailing, or just a result of the composite creating something like that out of coincidence when handling the composite data. I am not that much of an expert in this area, but if you tried similar tests using maybe a single image, a set of 15 composite, and a set of 30 images composite, and see if you get similar "circles" as you did in the 90 image composite, that might tell you if it is a recurring factor.

12-06-2015, 08:16 PM	#5
tduell Loyal Site Supporter Join Date: May 2015 Location: Melbourne Posts: 1,513	I see a similar story here <http://www.dpreview.com/forums/thread/625189?page=3>. Cheers, Terry

12-06-2015, 08:23 PM	#6
sjovolde Forum Member Join Date: Jan 2012 Location: Outlook, Sask. Photos: Albums Posts: 58 Original Poster	Thanks for the ideas. I had the camera set to keep all the previous images and the pattern shows up on all of them, it gets more pronounced as the shoot progresses. Shake reduction was turned off, and as far as I know the noise reduction has no effect on raw files unless I'm wrong. If its the focusing screen, why would it show up. I'm wondering it it's some sort of reflection inside the lens. Quartermaster James I was wondering what lens you used. The exif data just says 15 mm. Maybe it's a problem with using older M series lenses for this type of photography. Thank you Evan

12-06-2015, 08:37 PM	#7
colonel00 Site Supporter Join Date: Nov 2012 Location: Shawnee, KS Posts: 483	Nothing to really contribute but subscribing as this is very interesting...and, it was aliens Actually, a couple observations. First, to the OP, it looks like you have a couple bumps of the camera at the beginning and end. Not that this is the cause but just curious if you noticed them. QMJ, you might have some dust on your sensor as there is a reoccurring dark spot. Anyway, reading that linked thread, I also have to wonder if it is some moire effect since you are both using the K-3. I also see mention that this occurs when using a filter but I don't think eighter of you mentioned using a filter. Last edited by colonel00; 12-06-2015 at 08:43 PM.

12-06-2015, 08:42 PM	#8
Quartermaster James Loyal Site Supporter Join Date: Oct 2014 Location: Anchorage, Alaska Posts: 653	Originally posted by sjovolde Thanks for the ideas. I had the camera set to keep all the previous images and the pattern shows up on all of them, it gets more pronounced as the shoot progresses. Shake reduction was turned off, and as far as I know the noise reduction has no effect on raw files unless I'm wrong. If its the focusing screen, why would it show up. I'm wondering it it's some sort of reflection inside the lens. Quartermaster James I was wondering what lens you used. The exif data just says 15 mm. Maybe it's a problem with using older M series lenses for this type of photography. Thank you Evan These were taken with the Sigma 10-20 F3.5

12-06-2015, 08:43 PM	#10
Quartermaster James Loyal Site Supporter Join Date: Oct 2014 Location: Anchorage, Alaska Posts: 653	Originally posted by tduell I see a similar story here <http://www.dpreview.com/forums/thread/625189?page=3>. Cheers, Terry Intrigomon. I did have a protective filter on at the time.

12-06-2015, 08:51 PM - 1 Like	#12
sjovolde Forum Member Join Date: Jan 2012 Location: Outlook, Sask. Photos: Albums Posts: 58 Original Poster	Intrigomon, Quatermaster James. I was also using a UV filter. If I get a chance in the next day or so I'm going to try again with the same setup and remove the UV filter to see if it makes a difference. Would be an easy fix if that does it. Thank you everyone for the information. This forum always amazes me how fast you can get answers to your questions. Colonel 00 as far as the bumps go, I was shooting on my deck, and was wandering around for the half hour it took to shoot this. Next time I'll have to try stand still. Evan

12-06-2015, 09:05 PM	#13
DeadJohn Pentaxian Join Date: Jan 2011 Location: New York Posts: 4,833	That looks like Newton's Rings. I've never noticed it with my gear, but astrophotography forums have discussions of the problem. Also see https://en.wikipedia.org/wiki/Newton's_rings Does interval composite save each subframe in addition to the final composite? If yes, do you see the rings in the subframes?

12-06-2015, 09:07 PM	#14
Quartermaster James Loyal Site Supporter Join Date: Oct 2014 Location: Anchorage, Alaska Posts: 653	Originally posted by C_Jones As Quartermaster James and colonel00 mentioned, a filter or anything else covering the lens could easily cause a spherical "circle" to be created. I'm not sure I want to be pointing a non-WR lens upward into snowfall without one though!

12-06-2015, 09:07 PM - 1 Like	#15
DeadJohn Pentaxian Join Date: Jan 2011 Location: New York Posts: 4,833	Originally posted by sjovolde SNIP...UV filter...SNIP Flat filter plus curved front glass increases the risk of light interference patterns. Sounds more and more like Newton's Rings.