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| bio | website | |
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| location | ||
| age | ||
| visits | member for | 3 months |
| seen | 28 mins ago | |
| stats | profile views | 2 |
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May 16 |
answered | What are the pros and cons of Canon 5D III / 6D HDR Mode Vs HDR using a computer + HDR software? |
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Apr 13 |
answered | Capturing the Milky Way: what did I do wrong? |
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Mar 27 |
awarded | Supporter |
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Mar 25 |
awarded | Constituent |
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Mar 25 |
awarded | Caucus |
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Mar 7 |
comment |
Why is my far away background in focus even with a low aperture number? Actually, I explained it a little bit wrong. In this comparison, the entrance pupil of the 18mm needs to be multiplied by 20/23. However, in order to get the same framing with a 55mm lens, the subject distance increases, and hence, you need to multiply the part with the entrance pupil with 20/29. So you can see that there is more to it than just the entrance pupil. |
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Mar 7 |
answered | Not able to use faster shutter speed 1/4000 or faster |
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Mar 7 |
comment |
Why is my far away background in focus even with a low aperture number? The equation for background blur is: (focal length * magnification factor / aperture) * (background distance - subject distance) / background distance. The first part of this equation is the entrance pupil part. But effects of the second part are also shown in these graphs. So for the shot of the question you have a subject distance of 3ft and a background distance of 20ft+3ft=23ft. Therefore the difference in entrance pupil has to be multiplied with 20/23. So you are right that for this specific shot the entrance pupil is a good estimation, but it was more a statement in general. |
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Mar 6 |
answered | Why is my far away background in focus even with a low aperture number? |
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Feb 20 |
answered | What is a cheap standard/wide prime lens for Canon APS-C? |
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Feb 20 |
answered | How does background blur (bokeh) relate to sensor size? |
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Feb 19 |
awarded | Teacher |
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Feb 18 |
answered | How can I maximise that “blurry background, sharp subject” (bokeh) effect? |
