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12-06-2015, 11:36 AM   #1
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Sigma Sun Spots

Please see the attached photo. The sun is clearly reflected somehow in the lens, and apparent in the ghosted image at the bottom right. Can anyone tell me how to fix this with LR3, and better yet, why it happened / how to prevent it with this lens? Hood was on. No filter. Sigma 18-35mm f1.8.


Last edited by virtualjsk; 12-06-2015 at 01:07 PM.
12-06-2015, 11:43 AM   #2
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12-06-2015, 12:02 PM   #3
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QuoteOriginally posted by sergysergy Quote
No picture
Yes, no picture attached.
12-06-2015, 01:14 PM   #4
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QuoteOriginally posted by sergysergy Quote
No picture
I'm having difficulty figuring out how to add the photo from my iPad. Instead of letting me browse to photos, the link is asking for a url. Can you tell me how to add a photo that is on my iPad?

12-06-2015, 01:52 PM   #5
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QuoteOriginally posted by virtualjsk Quote
I'm having difficulty figuring out how to add the photo from my iPad. Instead of letting me browse to photos, the link is asking for a url. Can you tell me how to add a photo that is on my iPad?
Hit the "Manage Attachments" button below the post and upload as an attachment. It'll take you to a dialogue box where you browse your Ipad image library and choose the photo you want. Attachments are added at the bottom of posts.

You'll need to do this in a reply because, if I'm not mistaken, an edit of your original post won't let you do this.
12-06-2015, 03:23 PM   #6
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Sigma Sun Spots

QuoteOriginally posted by Kath Quote
Hit the "Manage Attachments" button below the post and upload as an attachment. It'll take you to a dialogue box where you browse your Ipad image library and choose the photo you want. Attachments are added at the bottom of posts.

You'll need to do this in a reply because, if I'm not mistaken, an edit of your original post won't let you do this.
Thanks! Hopefully, this will work...
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12-06-2015, 03:34 PM   #7
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Your subjects are heavily backlit, which means even if the sun was not in the shot, it still caused the flare. Wish you included the EXIF metadata, but if you did have the hood on, the only other thing you do here might be to stop down to a smaller aperture. On LR, I would just carefully burn the area of the flare to darken it.

12-06-2015, 03:41 PM   #8
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Thanks. I'll add the exif as soon as I can.
I rarely have any issues with my Pentax lenses. Could the Sigma coatings or construction be a factor too?
12-06-2015, 04:10 PM - 1 Like   #9
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QuoteOriginally posted by virtualjsk Quote
Thanks. I'll add the exif as soon as I can.
I rarely have any issues with my Pentax lenses. Could the Sigma coatings or construction be a factor too?
Yes, there are many factors that cause a lens to have more or less flare. Primes with less elements and groups will generally have less flare than zooms. Your Pentax DA 12-24mm has 13 elements in 11 groups vs. your Sigma 18-35mm with 17 elements in 12 groups. The quality of the coating, and the quantity of coats and on how many elements will also affect flare. Wide angle zooms naturally are more susceptible to flare. APO or ED elements don't really affect flare.

Correction: flare is usually more visible with smaller apertures, not large ones. Earlier I had written the opposite.

Last edited by Alex645; 12-06-2015 at 04:16 PM.
12-06-2015, 09:06 PM   #10
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QuoteOriginally posted by Alex645 Quote
flare is usually more visible with smaller apertures, not large ones. Earlier I had written the opposite.
With my own personal experience with this lens this is especially true, the probability of flare increases as you stop down. However there are some lenses where using them wide open also increases the probability of flare - Truth be told flare is a complex phenomenon that isn't easily nailed down with a few rules, it varies from one lens design to the next.

QuoteOriginally posted by Alex645 Quote
APO or ED elements don't really affect flare.
ED element's are still elements, they can contribute to flare just as any element can. But there is no such thing as an Apochomatic element, there are always three elements in a classic Apochromatic triplet to correct the focus of Green,Blue and Red wavelengths of light.



Sigma 18-35mm f/1.8 - all at 35mm, starting from the left, f/1.8,f/4,f/8,f/11

Last edited by Digitalis; 12-07-2015 at 12:17 AM.
12-08-2015, 05:29 PM   #11
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QuoteOriginally posted by Alex645 Quote
Your subjects are heavily backlit, which means even if the sun was not in the shot, it still caused the flare. Wish you included the EXIF metadata, but if you did have the hood on, the only other thing you do here might be to stop down to a smaller aperture. On LR, I would just carefully burn the area of the flare to darken it.
The EXIF should be in this image. 1/60 @F11, ISO400, 35mm. I've been playing with it in LR3, but I just don't really know what I'm doing or where to begin. Thanks for any advice you can offer.
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12-08-2015, 06:18 PM   #12
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QuoteOriginally posted by virtualjsk Quote
The EXIF should be in this image. 1/60 @F11, ISO400, 35mm. I've been playing with it in LR3, but I just don't really know what I'm doing or where to begin. Thanks for any advice you can offer.
The burn tool in LR3 had a reputation of freezing, but essentially that is the tool that I'd use to darken the flare so it was less apparent.
12-08-2015, 06:41 PM   #13
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QuoteOriginally posted by Alex645 Quote
The burn tool in LR3 had a reputation of freezing
...Adobe being unintentionally ironic.

Last edited by Digitalis; 12-08-2015 at 11:41 PM.
12-08-2015, 07:04 PM   #14
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QuoteOriginally posted by Alex645 Quote
The burn tool in LR3 had a reputation of freezing, but essentially that is the tool that I'd use to darken the flare so it was less apparent.
I may be off-base, but the hot spot in that photo looks like a back reflection (hot spot) off the sensor reflected back off the diaphragm blades. Translation? Not your garden variety flare. As for using the burn tool, good luck on making that one go away. The image is toast for the most part, IMHO.


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12-08-2015, 09:12 PM   #15
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QuoteOriginally posted by stevebrot Quote
I may be off-base, but the hot spot in that photo looks like a back reflection (hot spot) off the sensor reflected back off the diaphragm blades. Translation? Not your garden variety flare. As for using the burn tool, good luck on making that one go away. The image is toast for the most part, IMHO.


Steve
Thanks... Is there any explanation for this?
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