Circle of confusion. Considerations in digital photography and hyperfocal table
In previous entries on the Circle of Confusion , we have seen as depending on the assumptions, the calculation of the circle and, consequently, the hyperfocal distance , could suffer a large variation.
In addition to these considerations, we must bear in mind that in the world of chemical photography, we appreciate the sharpness in the print, but in the digital world, we tend to value it on your computer, with a magnification of 100% and just 25 cm of the screen.
If we do that in a camera, for example, the Sony Alpha 900 24.6 megapixel, and using a 19 "monitor with a resolution of 1,600 x 1200 pixels, would be looking back about five feet diagonal , ie at a magnification of about 34 times the size of the sensor.
Obviously more blur appreciate that under the conditions stipulated before, because in this case should work with a circle of confusion: 0.2 / 34 = 0.006 mm, which is the same, 6 microns. But here other factors appear related to the size of the pixels.
The Sony A900 has a 6,048 x 4,032 resolution in a sensor pixels 24 x 36 mm. This means that each pixel is one box side 6 microns. Considering the Bayer filter , four adjacent pixels are needed to collect all the color, so that each valid pixel would be 12 microns side.
Therefore, it is physically impossible to record anything about 6 microns, as the smallest dot with full color, which can capture the sensor is 12 microns.
If we make the same calculation for a camera with APS-C sensor of 10 megapixels, such as the Canon EOS 400D or 1000D , we see that by looking at the photo at 100% we introduce an extension equivalent to nearly 36 times, so we would need an even smaller circle of confusion, of only 5.5 microns. But in this case the pixel is 5.7 microns, so that each pixel will be 11.4 microns, and the situation is repeated in similar conditions.
Something similar happens when we make a cut of the picture you have registered the sensor and extend to 15 x 20 of our initial assumption. When trimming, do not mind the size of the sensor, but the crop, so the expansion will be greater, the circles of confusion will be expanded and will become more apparent loss of depth of field and sharpness.
So what value of circle of confusion should we use?
Given the physical limit imposed by the pixel size, we see that the formula of Zeiss is very close to this end APS-C cameras. Moreover, although Canon is a minimum of d/1.000, it seems that even they use it and go up d/1.250.
Perhaps because of this, the value most often used in the calculation is intermediate between the Canon and Zeiss, ie d/1.500, with which we obtain values of the circle of confusion of 29 microns to 35 mm cameras , and 20 microns for the APS-C.
As we know that is an estimate and will depend largely on the size to us to print the photo and the distance we see it, we can from this figure as a good enough value. In fact provide greater clarity (and, in turn, less depth of field) than that used by Canon in the design of their objectives , although less clearly than with the calculation of Zeiss.
In the case where we stand before the picture of our life, that which we plan to expand to fill the living room wall, we can use the trick to calculate and use the hyperfocal for a diaphragm, but the goal set in the next smaller aperture. That will give us an extra mattress sharpness that allow us to expand more smoothly.
On the other hand, if a particular photographer specializing in large formats, and prints most of his photos in sizes above 15 x 20 cm, would be prudent to adjust the calculation to your needs to ensure that even in large prints photography it still looks as sharp as expected.
With this view I have recalculated the hyperfocal chart I posted last July, to use CoC = d/1.500 as the default in both sensor sizes. Probably more now their numbers match those of other tables and calculators on the network and create less confusion, but differs from the first one published.
Also, as you can see in the picture, I added the ability to change this approach so that the table be recalculated with any of the other three values we have seen at the entrance to the circle of confusion grounds.
And to top it, I have also included the ability to adjust the exact size of your camera sensor, since not all APS-C have the same measure, not everyone uses full frame or APS-C. In this way each photographer can adapt very easily and more flexibly to their needs, including the use of compact cameras or medium format .
You can download the spreadsheet here: hyperfocal Table Excel 2.1
Other articles in this series:
- Circle of confusion. Fundamentals
- Circle of confusion. Calculations
- Circle of confusion. Considerations in digital photography and hyperfocal chart (This article)
The zip file Excel hyperfocal Table 2.0 is corrupted. Does not open.
Thanks for the tip Mary, but I if I can open it without problems.
Anyone else with him? Does anyone else to open it without problems?
It seems that more people can not open it, so I returned to compress it and have replaced.
Try again and if still fails to say so do not hesitate to seek a solution.
I feel the problem.
IF it is true, fails.
William
February 1, 2009
Thank you very much for your consideration and help to raise the table, but I regret to say that does not open. Thank you very much again,
Paula
I really do not explain. I've compressed in several ways, I've tried on several computers and work for me.
Please you can tell me which operating system, browser, decompressor and version of Excel are you using. See if you find out how to fix and what you can download it.
Ah! and this can forgive, but for now I have no idea why happens.
Yes, I too fails. I open it with winrar and tells me that the file is corrupted.
What version of winrar please? I open it with Winrar and it works
Hello I have seen the comments on the excel table and I would say something.
I've downloaded from the explorer and I could not open it by any means, but then I tried opening the link to open the page loaded in firefox with no problems. Just as this can help someone.
Regards
Indeed John. Thank you! I always downloaded with Firefox and so I failed, but Explorer, for some strange reason it is loaded. Now see if you find out why, and how to fix it.
Internet Explorer seems corrupted ZIP files on download. If you download another browser or by using Explorer if you have installed a download manager, it does not.
I found a reference to a problem of this type documented by Microsoft, perhaps someone will serve, but at least I do not solve anything. In any case this is the report from Microsoft: http://support.microsoft.com/kb/308090/es
I will continue researching in the meantime all I can say is that you use another browser or installing a download manager like Orbit Downloader: http://www.orbitdownloader.com/
Constraining the problem: it seems that only fails with Internet Explorer 7, both XP and Vista. For once so IE6 works better than 7.
Keep you informed.
Hello, I tried descargarme tables but I could not. could someone send me the tables for CANON EOS 450
Thanks
Titu course, I have given the postman and I said "this is for Titu". I guess I know how to advertise thee reach the
Well, seriously, I think it is finally resolved and can be downloaded without problems. If anyone is still failing to alert and continue looking for solutions ...
Very, very grateful for your explanations. The table, a gift.
I always thought that the larger the sensor, the lower range of hyperfocal, if sounds like this, but it is just the opposite is not it?.
Too bad I see, the hyperfocal in the case of the Sigma DP1 with a sensor of 20.7 x 13.8 requires close much the diaphragm and this is crucial for me, that I use with manual focus and viewfinder to avoid losses time with a focus automátco that, according to tests, leaves much to be desired.
In any case, thanks for information as clear and valuable.
In any case, thanks for information as clear and valuable.
Nenon, the hyperfocal is a range, but a point. What we do have is that the larger the sensor, the less depth of field (the range that appears to be sharp). So the cameras with large sensors are best for making creative use of selective blurring, so the video function of the 5D MII is highly regarded for some uses, it allows more blur than normal video cameras, precisely because size of the sensor.
I'm glad to serve you.
Hello thank you very much for this contribution, however I can not make it work. Independiemente esocoja the values at all focal lengths gives me 0. What I see in your screenshot is that CoC down the diagonal, gives you 18 and 18934 ami perhaps is only you have to mostar only 2 digits. Or do not know, but you could give me a little help on that shows me all at 0? for example to all ranks 18mm gives me 0
The sensor size is 23.6 × I 15.8
Thank you very much, constantly chekare your blog to see if you could answer me.
Thank you.
Carlos, this is very rare. You should never give you a figure as high CoC. In theory if you put very high numbers for the size of the sensor, it could go, but the blade is limited to stick figures can not be greater than 100, and a sensor 100 x 100 mm, the most you would leave a CoC of 94 microns.
The zero you all the CoC is so loud you out.
Just in case a problem with how to interpret the decimal place the sensor test 24 x 16 only to see if that turns out well (it should go CoC = 19, which is the same as putting it would exact decimals).
Thanks
I descarla and decompress the first. With firefox, of course.
Now I need to interpret all this data.
Is I have a Canon 450D and 50 mm. 1.8 II most photos I get very blurred. This is because what do to I'm not respecting the distance hyperfocal table, what the objective is exclusively for portraits, or the machine has problem?
The green numbers do not understand what they mean. How it works, somebody put an exam. pliiis!
Drona, virtually any target is unique to anything. But without seeing the photos can hardly say it is due. This objective f / 8 is extremely nífido.
What the numbers mean and how to use it as explained in this article series. Review them to understand.
good ... oscar
the vrdad I have the same problem as Carlos have the same sensor and the results in Table tambienson the same ...
sorry if I got to review the formulas in the table and in the cell the value of CoC is: 1000 * S13 / $ R $ 19; WHERE R19 NO VALUE as the table is protected not you could make any changes and rebice only that made in another spreadsheet and so I'm cooking the aforementioned sensor 19 for this ...
hasmelo know if I'm wrong, please, thanks
thanks greetings
AE2, nothing to forgive. But the R19 cell is correct, although not visible if you have a value, namely the denominator of the R17 that is highlighted in gray just above.
I've been testing again, and I would work properly. The only thing I can think is that depends on the software version of Excel you use is it? What version?
good, oscar
profecional use excel 2003, I miss
the denominator of the r17 is 1.5 (1 to 5/10) or 1500 (1500) since the latter value being the table would be complete with all data ... according to me ... I hope we can solve the problem because your contribution is very great because when one is a self-taught amateur and also unknown to the cenda continue to go down then learning to read by reading here over there a bit of this a little of the other t the truth is an endless list of terms, concepts, principles, and so on. that has the picture even more with digital photography ...
greetings and thanks ...
Okay, is because it is. I have given the track with your question. Have the English operating system, specifically with the configuration of numbers in English, using the decimal separator, so that means one and a half, instead of 1500. As I can do some adjustments in the table and up the version 2.1.
It is up to date.
Re-download the new version and now if you should work.
by oscar ...
now if it works, I'm glad to have been useful, I entered my values and the CoC to censor me d/1250 23um which is closest to 22um which corresponds to a sony alpha 200, according to data of this page http:/ / www.dofmaster.com / digital_coc.html as I get it ... I do not remember jajajjajajaja in this case the CoC should be d/1300, 22um to give me so with your board makes a rough ...
your help is appreciated, Greetings ...
ttp :/ / www.flickr.com/photos/36953330 @ N08 /
I enpesando in the picture ...
I have a question, I have been reading the articles and when I thought I had something clear that I have become a liar. I downloaded the excel (great job by the way) and citing the circle of confusion 1,500 for a camera of 22.2 mm APS and 14.8 mm, if I select a 50mm lens for a portrait at a distance of 3 meters and put the value higher f, 22, would you need to focus at a distance of 6.4 m for the photo to stay properly focused? What a 17mm lens for landscapes need less meters? I think I do not understand the use of this distance and I interpret the table. Could aclarármelo a little?
Thank you very much!
With 50 mm and f22, the focus at 6.4 m will clear everything from 3.2 m to infinity. If the subject is 3 m you will not clear, but if you put a little further each other.
Putting a 17 mm depth of field is greater clarity and will more closely (for the same values from only 35 cm), but it is an appropriate goal for portraits, because the angular deform much if you approach the subject.
In any case, where a portrait is not recommended to use the hyperfocal, because you want it to be sharper eyes. It is best to approach them but sacrifice some sharpness in the background.
Oscar thank you very much. Googling I found with some effort I printed to an acceptable size (lack of practice with Excel ...) I'll tell you the results.
A greeting
Fernando
Good day Oscar!
Recently I started in photography and search and requetebusco with the idea of knowing more about this world.
I found your board and I have the following doubts: The Iperfocal Distance (m), that (m) is meters or millimeters? her see that resulting from FF and Focal length is the distance from which the target begins to see clearly?, and finally understand that the top line (1.4, 2, 2.8, 4 ....) are openings diaphragm and if to use a different diaphragm and alter the media?.
I hope you understand my question.
A greeting from Spain
Hi Paul,
- Always short for my feet is that of mm is mm
- Your second question does not quite understand. If you mean the values that populate the table are numbers of hyper, and will be sharp from the middle of these figures to infinity.
- For the last article where I refer to the table published for the first time http://lucesyfotos.es/blog/91/tabla-de-hiperfocales-de-bolsillo If you use other values as comfortable and fast is that aproximes.
Regards
The articles are excellent. I never understood this concept of hyperfocal and now, finally, I have.
Thank you very much and very practical table.
I came a doubt. Does it affect the calculations of hyperfocal distance that the camera is DX or FX format?. I ask because in the formula to calculate the hyperfocal data is used as the focal length and DX format is not the same objetovo of the theoretical and actual or equivalent in 35mm. That is, if I am using a 50mm on a DX body, in the formula use the value of 50 or its equivalent in 35mm, or 75mm
Yes, of course it affects. It's what I mean (in general) of 24 × 36 sensors and APS-C, only Nikon FX and DX calls respectively. In practice taking into account using a different value for the circle of confusion with the size of the sensor, and calculating the actual focal length lens. According to the table is made you can put any sensor size (height x width), including a medium format camera or a mobile phone.
I'm glad you have been helpful in clarifying the concept.
Athletic.
I downloaded version 2.1, and when I printed, I've noticed that above where the CoC = d/1500 = 0.029 = 0.027mm puts d/1000 not know if the link will be bad, or the table is correct, but did not match any of the tables that you put on the blog.
For example to me come these parameters:
In APS
34mm f8 = 5.7
See if you can answer me if I printed the correct table, or link to descargarmelo.
Thank you very much in advance.
A greeting.
If you prefer to 1/1500 but do not have to select that value before printing
Thank you for the article and teaching and in practical plan for the Excel table. Very practical. This is what I was looking for.
Regards,
Pere