Jump to content

Bullseye Artifact on Long Exposures

ENGTick

By ENGTick,
in Sony Alpha Full Frame Cameras

 Share

Recommended Posts

ENGTick Newbie

ENGTick

Posted
Posted (edited)

Hi. Newbie hobbyist who started last June. Does anybody know what would cause the "bullseye" in the center of this shot? I shot this using an a7r iii with FE 2.8/24-70 GM lens. My settings were 15 sec, f/4, iso 800. Also, I didn't see the bullseye on shots at 5 sec, f/4, iso 800. I had Long Exposure NR off for both shots. Thanks.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Edited by ENGTick
Link to post
Share on other sites
VTC Rising Star

VTC

Posted
Posted

Odd but taking a wild guess here... Stabilization turned off? It's recommended for tripod use. When shooting with a matte box if I'm not careful shooting towards the sun or have the flag off position I'll get a reflection of the lens on the 2nd surface of the filter but it presents much larger than what's shown here.

Link to post
Share on other sites
  • 1 year later...
ArnoldLayne Newbie

ArnoldLayne

Posted
Posted

Allow me to add my own 'bullseye puzzle. I agree the OP photo looks like Newton's rings, now that I know what that is. But my bullseye is much larger. Have you seen this? It's not dependent on lens. a6000

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites
dbmiller Enthusiast

dbmiller

Posted
Posted
16 hours ago, ArnoldLayne said:

Allow me to add my own 'bullseye puzzle. I agree the OP photo looks like Newton's rings, now that I know what that is. But my bullseye is much larger. Have you seen this? It's not dependent on lens. a6000

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Looks like the lens correction being applied for vignetting. And possibly then pushed in post?

Try turning off "Shading Comp." on the camera. Google that and you'll find a bunch of info.

Link to post
Share on other sites
  • 2 months later...
txtrigg Newbie

txtrigg

Posted
Posted (edited)

I have the same issue with my A7RIII - I looked at my raw files  out of the camera and they all had this bull's eye. I'll try the same Shading Comp setting. I was also using compressed raw files - I know there have been some issues with compressed raw images and originally thought this was related. I'll have to go see if I can find any of them - I think I trashed them all because the bull's eye was so stark it made them unusable.

 

*edit: added my camera model.  

Edited by txtrigg
Link to post
Share on other sites
  • 2 months later...
XKAES Experienced

XKAES

Posted
Posted (edited)

I agree with Eskimotom.  These look like very mild lens edge reflections onto the camera sensor -- filters would add to this, as long exposure noise would, too.  Take the same picture with a different lens at the same speed.  If it shows up again, but looks larger, smaller, fewer or more rings -- it would suggest mild internal lens reflection.

One possible solution MIGHT be a longer lens shade or a slower shutter speed (to reduce noise -- which I assume was already reduced).

Edited by XKAES
Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Posts

    • felipe
      Sony 16 mm f/1.8 G: Vea las primeras fotos tomadas

      By felipe · Posted

      Hola, parece que estan agotados, saludos Felipe 
    • XKAES
      JPEG options?

      By XKAES · Posted

      I'd suggest you start by running a simple test.  Take pictures of a typical scene/subject and each of the JPEG settings your camera offers.  Then compare them in the output that you normally produce.  You may or may not see a difference.  I normally shoot at the highest JPEG level and save that file -- but make a smaller file (lower resolution) for normal/typical use. There's plenty of editing that you can do with JPEGs on your computer -- depending on your software -- and there are features in your camera that can help out, as well.  That depends on your camera.  Put them together, and it might meet your needs.  For example, your camera probably has several bracketing features that will take the same shot with different settings with one press of the button.  Then you can select the best JPEG to work with on your computer.  I frequently use this feature to control contrast.
    • Cameratose
      JPEG options?

      By Cameratose · Posted

      If you set up some basic presets in your processing software and use batch processing, you don't need jpeg at all. I shoot RAW only, use (free) Faststone Image Viewer which will view any type of image file to cull my shots, and batch process in Darktable. I can start with 2000-3000 shots and in a matter of a few hours have them culled, processed, and posted. A handful of shots, say a couple hundred from a photo walk, are done in minutes.  This saves card space, computer space, and upload time.  The results are very good for posting online. When someone wants to buy one or I decide to print it, I can then return to the RAW file and process it individually for optimum results.  I never delete a RAW file. Sometimes I'll return to an old shot I processed several years ago and reprocess it. I have been very surprised how much better they look as my processing skills improved.  

  • Topics

×
×
  • Create New...