Luminous Landscape Forum

Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: dannyboy on April 17, 2006, 02:52:33 pm

Title: Sensor bloom
Post by: dannyboy on April 17, 2006, 02:52:33 pm

Can anyone explain sensor bloom or point me to an article that addresses the topic
Thanks!

Title: Sensor bloom
Post by: Richowens on April 17, 2006, 05:04:13 pm

This page gives a good example with a D70.

Bjorn Rorslett's test (http://www.naturfotograf.com/index2.html)

Look on the third page of his D70 review.

Hope this helps.

Rich


[attachment=471:attachment]


Here is one of mine,with a 70-300 at 300, stopped down to f11. It helps, but needs more.

Title: Sensor bloom
Post by: Dmitry on April 19, 2006, 04:21:52 am

Quote

Can anyone explain sensor bloom or point me to an article that addresses the topic
Thanks!
[{POST_SNAPBACK}][/a] (http://index.php?act=findpost&pid=62820\")

One reason is the following: Camera sensor is Bayer pattern normally (or Color Filter Array -CFA), i.e. is consisted from 4-point patterns where 1 red sensor, 1 blue sensor and 2 green sensors (GRGB Bayer pattern). Sensors catch light with different frequency. When sensor overcharged, energy (charge) spills over to neighboring sensors. But red, blue and green light have different energy, and so we can see purple fringing around edges on brithness background.
Anower reason of chromatic aberration (CA) is cheap optic. All lenses are calculated by "green channel" without zoom and when you zooming you recieve different focus plane on different frequency. As result you can see CA on image edges. (CA more to image border and there is no CA on image center).

Short help you can see on DPReview
Blooming
[a href=\"http://www.dpreview.com/learn/?/Glossary/Digital_Imaging/Blooming_01.htm]http://www.dpreview.com/learn/?/Glossary/D...Blooming_01.htm[/url]

CA
http://www.dpreview.com/learn/?/Glossary/O...erration_01.htm (http://www.dpreview.com/learn/?/Glossary/Optical/chromatic_aberration_01.htm)

Title: Sensor bloom
Post by: jani on April 20, 2006, 05:41:04 pm

Quote

This page gives a good example with a D70.

Bjorn Rorslett's test (http://www.naturfotograf.com/index2.html)

No, that's the link to his front page.

Bjørn is an excellent photographer, but unfortunately, he uses frames to the detriment of usability.

Try finding the link to the frame you're viewing.

Title: Sensor bloom
Post by: Richowens on April 20, 2006, 11:40:42 pm

I didn't edit enough after I realized that link pointed back to his home page.

Just go to that page, scroll down to his D70 review and go to the third page in that review. He shows an example of sensor bloom and give a short explanation of why.

Sorry for the error.

And yes, his site is strange to navigate.

Rich

Title: Sensor bloom
Post by: jani on April 21, 2006, 03:14:46 am

Quote

I didn't edit enough after I realized that link pointed back to his home page.

Just go to that page, scroll down to his D70 review and go to the third page in that review. He shows an example of sensor bloom and give a short explanation of why.

That would make it this page (http://www.naturfotograf.com/D70_rev02.html#top_page).

The examples Bjørn give are indeed very good.

Title: Sensor bloom
Post by: Richowens on April 21, 2006, 10:37:00 am

Thanks Jan,

I figured out how to find the address and do a copy and paste.
I learned something new today, so that makes today special.

Thank you!  

Rich