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Author Topic: A new tool for the production of high quality output  (Read 7864 times)
BartvanderWolf
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« Reply #20 on: August 27, 2013, 03:21:51 AM »
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I will be a great tool, but why you don't use fixed dpi settings according to actual printers drivers settings - Epson use 360 or 180-240-360-380-720 steps (and 300 its wrong for Epson driver), HP and Canon use 300/600ppi.
Durst Theta use 254ppi, Lambda 400ppi and so on.

Hi,

I'm not sure if you are referring to the PPIs calculated by the tool, or an addition (say section 1.5) for the final output bit. The latter part should be taken care of by the application you print from.

Maybe I need to elaborate a bit more on the PPIs that the tool calculates, yes they are calculations. They are not fixed goals as if to match a certain output device (in fact they are the opposite), but rather the result of the angular resolution requirements to fulfill the required human visual acuity of our viewers' eyes.

When we enter the acuity level we need to satisfy, and the viewing distance, and the size (=magnification at a distance) of our magnified image that's captured on sensor, we can calculate the number of output lines or pixels it would require to achieve that goal. It then becomes necessary to have the output modality adapt to the produced data quality, and that most likely requires an additional resampling step, because the printer's resampling is not good enough.

I've attached an example of the final steps that are required, and used Photoshop CS6 but it is usually similar in most other applications.

Attachment 1 gives the screen captured result, based on the earlier input were an image is produced of 5616x3744 pixels and it should be given an output resolution of 291.1 PPI.

That is done in attachment 2. Note that the resampling checkbox is not ticked, so we only change the metadata of the file as it is. The unchecking of that box is the first thing that needs to be done, before changing any of the other settings! Then, at this stage, the PPI setting is nothing more than a label, the physical file size is not affected, the number of pixels remains the same. We can then either adjust the output size as we entered it in section 1.4 of the tool, or adjust the PPI setting. Both should give the same results, within rounding error precision.

Now on that basis, and in Photoshop we don't need to leave the dialog box, we now do tick the resample checkbox, and enter the PPI requirements for the output modality we want to use. That is shown in attachment 3. Now new pixels will be created, and the file size will grow when we click OK.

In the example I only resampled up to the nearest 360 PPI setting to e.g. print on an Epson printer. Personally I would have gone to 720 PPI, because with deconvolution sharpening I can recreate even more accurate sharpening, and even exaggerate it a bit, because artifacts at that level will be almost impossible to see. I could also add some noise, it will be to small to really see clearly, to give too smooth areas a bit of dithering structure, to avoid posterization in output. I would actually not have used Photoshop's Bicubic Smoother resampling at all, but Photozoom Pro, because that does a better job, but that's for another discussion thread.

Cheers,
Bart
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hjulenissen
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« Reply #21 on: August 27, 2013, 03:35:30 AM »
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I think it would be interesting with such tools integrated with the image capture device itself (just thinking loudly here, not making any demands to you, Bart).

Why can't something like the Nikon D800 run simple Android-like "apps" that allows you to add this kind of functionality and control e.g. aperture directly from the app, possibly integrating liveview preview?

My Sony RX100M2 allows Android/iOS remote viewfinder control across WiFi. The same functionality seems to be offered by the strange DSC-QX100 / DSC-QX10. I wonder how closed that API is. Being able to preview comfortably on something like a retina iPad with great added insight into how camera settings affects the final print could really be something.

-h
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BartvanderWolf
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« Reply #22 on: August 27, 2013, 04:37:18 AM »
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I think it would be interesting with such tools integrated with the image capture device itself (just thinking loudly here, not making any demands to you, Bart).

Hi,

Well, they have not contacted me, yet Wink . First come, first considered.

I think camera makers would only show interest in adding complexity (for them) if they estimate it would sell more cameras.

Cheers,
Bart
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hjulenissen
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« Reply #23 on: August 27, 2013, 05:35:28 AM »
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I think camera makers would only show interest in adding complexity (for them) if they estimate it would sell more cameras.
Which is why I think that "photo-oriented" people will have to hope for (ugh) facebook integration, angry-birds and appstore. Only when camera makers choose to include such flexibility (to satisfy the masses), can the photo-geeks hope to be able to piggy-back on the APIs/openness to include narrow photo-oriented stuff. I predict a large upswing in photographic creativity as a result.

Samsung is my best bet.

-h
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BartvanderWolf
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« Reply #24 on: August 27, 2013, 06:49:54 AM »
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As requested, I've just added the initial support for Non-SI units of distance to the Camera-lens settings sections 2.1) - 2.1.2).

A number of associated fields (e.g. 2.1.3) and the Hyperfocal distance) are updated as well, depending on the distance unit choices. The Hyperfocal distance is reported in the same type of units as the Focus distance, because one might want to take that clue as a new focus distance. The type of units for the Front and/or Rear DOF distance will determine the scaled units for the total DOF range at 2.1.3). That Total DOF range will be scaled to relatively meaningful numbers and units, to allow an accurate value in a few digits without too many zeros before or after the decimal point.

There are more distance fields that need to be enabled for Non-SI units, but I wanted to already share this for those who can't intuitively relate to metric units for the most important distances. I also added the relatively unpopular yards, for those who want to try their skills at shooting sports.

I need to do some more testing, but it looks like I didn't break anything vital by adding this.

Later I may add a simple choice to switch all units with a single click, but there may be specific requirements for more detailed unit choices, hence the current high level of control (I also added some larger distance units - km and mi - to the Rear DOF selection, to allow input with fewer digits in some cases).

Cheers,
Bart
« Last Edit: August 27, 2013, 06:53:02 AM by BartvanderWolf » Logged
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« Reply #25 on: August 28, 2013, 06:31:01 AM »
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I think it would be interesting with such tools integrated with the image capture device itself (just thinking loudly here, not making any demands to you, Bart).

Why can't something like the Nikon D800 run simple Android-like "apps" that allows you to add this kind of functionality and control e.g. aperture directly from the app, possibly integrating liveview preview?

My Sony RX100M2 allows Android/iOS remote viewfinder control across WiFi. The same functionality seems to be offered by the strange DSC-QX100 / DSC-QX10. I wonder how closed that API is. Being able to preview comfortably on something like a retina iPad with great added insight into how camera settings affects the final print could really be something.

-h

There are apps that do this now.  Helicon Remote has a DOF calculator built in that allows you to change the CoC size to whatever you want and outputs DOF based on that.  It doesn't provide a preview; however.  That would simply take too much processing. 

Typical DOF calculators work the way they do because they're based on a standard.  That standard is a CoC of .01 or smaller being considered in focus in an 8x10 print viewed at a certain distance.  I forget what the viewing distance standard is off the top of my head.  It's a reasonably simple matter to redo the calculation for other print sizes.  You want to make a print 4x the size, that enlarges all the CoC by 4x.  What does that do do DOF? 

Here's the question I have.  Standard DOF calculations have served photographers well for decades.  Is the difference in the digital age so great that it has a marked difference in a print?  I'm asking not to be combative but rather to try and understand.  I know some on here think every question I ask is to be combative.  Roll Eyes
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BartvanderWolf
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« Reply #26 on: August 28, 2013, 06:35:25 AM »
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I've expanded the support for non-SI units to include the Object dimension settings.

Additionally I've changed the handling of the (optionally chosen) resulting optimized Focal length value. It formerly defaulted to nice rounded (to 5mm) focal lengths, but that also introduced slightly less accurate results for the depending parameter values. Now, one can double-click on the Focal Length field, and it will do the rounding to the nearest 5mm, and additionally recalculate the entire model where it depends on the focal length.

The Object dimension settings allow to automatically set all other related parameters, and can be used if the object dimensions are already known in advance. This can be used with reproduction of e.g. paintings/drawings, or when the main subject has a known size in the plane of optimal focus.

Do note that it only applies to the subject dimensions in the focus plane (that's why that is usually set first, or is optimized for), and that the use of a different focal length will produce a different rendering (size and blur) of the foreground and the background features. The photographer must still make creative choices, but won't have to worry about fitting the main subject in the frame.

This still leaves the 2.7) Total Depth of Field (and it's dependents) to be enabled for non-SI unit input, but that's a tricky parameter to change anyway, because it impacts the original quality goal for the required image size. It is generally not advised to change it there, but e.g. change the Aperture if more or less DOF is needed.

The value of the total DOF is reported at 2.1.3) anyway, and there it uses the distance units that were set for the Front or Rear DOF distance.
 
Cheers,
Bart
« Last Edit: August 28, 2013, 07:33:03 AM by BartvanderWolf » Logged
BartvanderWolf
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« Reply #27 on: August 28, 2013, 07:20:06 AM »
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Typical DOF calculators work the way they do because they're based on a standard.  That standard is a CoC of .01 or smaller being considered in focus in an 8x10 print viewed at a certain distance.  I forget what the viewing distance standard is off the top of my head.

Hi Bob,

Some use 12 inches (30.48 cm) viewing distance, others (e.g. Zeiss) assume 25 cm (~10 inches) and also use a lower quality (larger COC, 2 minutes of arc instead of 1 minute). Of course an 8x10 inch (contact) print requires a different (simply scaled) parameter for other distances, and also may not fit everybody's requirement for quality. Sometimes lower quality is permissible, but at other occasions uncompromised quality is required.

A higher quality standard also allows to use a better quality sharpening, because more pixels will be available, and that enhances the almost tactile aspect (cardboard versus leather) of how material structure is rendered in the print. This is very important in product shots, less so in portraits (unless the ultra-realistic style is used).

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It's a reasonably simple matter to redo the calculation for other print sizes.  You want to make a print 4x the size, that enlarges all the CoC by 4x.  What does that do do DOF?

DOF is also dependent on Focal length, which renders foreground and background detail at different sizes due to angle of view. So there is also a 'quality' aspect to DOF, even before considering Bokeh.  

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Here's the question I have.  Standard DOF calculations have served photographers well for decades.  Is the difference in the digital age so great that it has a marked difference in a print?  I'm asking not to be combative but rather to try and understand.  I know some on here think every question I ask is to be combative.  Roll Eyes

Well, I'm not so convinced that the DOF calculations have served photographers that well. Maybe well enough, given a situation where one already had some other experience with, but I doubt they served them well in very unfamiliar circumstances.

In addition, digital imaging allows the use of images for rather different purposes. Never before has is been so easy to produce poster sized output, sometimes even on one's own printer. Enters the quality question. Being able to do something doesn't necessarily mean it is gong to be of adequate/satisfying/necessary quality ...

For that purpose I think a better, or easier to use, predictive model which includes the specific limitations of the recording medium (such as sensel pitch limitations), is helpful.

Cheers,
Bart
« Last Edit: August 28, 2013, 07:36:53 AM by BartvanderWolf » Logged
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« Reply #28 on: August 28, 2013, 07:34:42 AM »
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Hi Bob,

Some use 12 inches (30.48 cm) viewing distance, others (e.g. Zeiss) assume 25 cm (~10 inches) and also use a lower quality (larger COC). Of course an 8x10 inch (contact) print requires a different (simply scaled) parameter for other distances, and also may not fit everybody's requirement for quality. Sometimes lower quality is permissible, but at other occasions uncompromised quality is required.

Yes, those are the numbers I recall now.  I think you've hit on it with that bolded bit, Bart.  It's also quite subjective.  Reminds me of the issue with temperature ratings for sleeping bags.  Those are based on what the 'average person' should be able to achieve.  Thing is, there is really no such thing as the average person.  We're all individuals. 

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A higher quality standard also allows to use a better quality sharpening, because more pixels will be available, and that enhances the almost tactile aspect (cardboard versus leather) of how material structure is rendered in the print. This is very important in product shots, less so in portraits (unless the ultra-realistic style is used).

Don't disagree.  I'm wondering how big the difference is.

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DOF is also dependent on Focal length, which renders foreground and background detail at different sizes due to angle of view. So there is also a 'quality' aspect to DOF, even before considering Bokeh.  

True.  And the standard calculators take that into consideration, along with distance to subject which is the other component of magnification.

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Well, I'm not so convinced that the DOF calculations have served photographers that well. Maybe well enough, given a situation where one already had some other experience with, but I doubt they served them well in very unfamiliar circumstances.

I think to the extent that the people who used them knew what was being conveyed, the tool served them well.  Not a lot of people used them, I think is more to the point.

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In addition, digital imaging allows the use of images for rather different purposes. Never before has is been so easy to produce poster sized output, sometimes even on one's own printer. Enters the quality question. Being able to do something doesn't necessarily mean it is gong to be of adequate/satisfying/necessary quality ...

Yes, just because we can doesn't mean we should.

Quote
For that purpose I think a better, or easier to use, predictive model which includes the specific limitations of the recording medium (such as sensel pitch limitations), is helpful.

Cheers,
Bart

Again, I don't necessarily disagree, it's the quantum of the difference or improvement that I'm interested in.  I haven't used  your tool yet as I'm on a mobile device, but will take a look later and do some comparisons.
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Fine_Art
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« Reply #29 on: August 28, 2013, 08:33:06 PM »
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Hi Peter,

You're welcome.

I obviously agree, COC values without being output referred make little sense.

Section 1) of my tool now also make it much easier to answer the question;
  • How large can I print a file from camera 'x' ?

Before, the obvious answer was; How large is the paper your printer can handle?
But that didn't say anything about the quality one could expect.

Now we set our required quality level, viewing distance, and camera sensor parameters,
and out comes the maximum print size. Anything larger has lower quality, anything smaller
will have even higher quality. As simple as can be.

Cheers,
Bart

Very valuable, thanks!
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BartvanderWolf
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« Reply #30 on: August 29, 2013, 02:33:33 AM »
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Very valuable, thanks!

You're welcome. I've just added a small bit of additional information to section 1.4), something that I thought might be useful (while I'm also working on the further implementation of non-SI units).

I've noticed that some users have difficulty relating the maximum output size that a camera can produce, at the selected quality level and viewing distance, with how large a 'normal' size print would be. That's because of the viewing distance variable.

Hence I've added a note about those 'standard' size dimensions, assuming that an image with a diagonal dimension equal to the viewing distance, could be classified as 'standard'. It is generally accepted that such (diagonal=viewing distance) dimensions will allow to overview the image content easily because of its moderate angular field of view.

That should make it easier to immediately see if an image would be perceived as impressively large (requiring to step back to take it all in as a total composition), or small (which tends to make people walk up closer to look at details).

Not a major addition, but it could be useful when we produce something with a size or viewing distance that's different from what we're used to.

Cheers,
Bart


P.S. I've also added a comment about viewing perspective and how that relates output size to focal length and viewing distance used. That might also be a useful consideration when the shooting has yet to take place. It's all a lot of information crammed into a tiny space, so maybe I'll think of a different way of presenting it, but it is the logical place in the planning process to consider it.
« Last Edit: August 29, 2013, 08:07:28 AM by BartvanderWolf » Logged
FranciscoDisilvestro
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« Reply #31 on: August 31, 2013, 08:56:49 AM »
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Bart, thank you for this valuable tool.

If you don't mind, I have a few questions related to macro photography,

1) Aperture: Should I use the equivalent aperture (adjusted for magnification) or the lens uncorrected aperture?
2) Focal length: in lenses with internal focusing, does it matter if the focal length varies at close range? Should I consider the adjusted focal length?
3) Can you recommend a procedure to determine pupil factor?
4) Focus stacking: are the steps the same regardless of the method to change focus between images? (Focus lens, change camera+lens position or moving the back only when using a bellows)

Thanks,

Regards

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BartvanderWolf
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« Reply #32 on: August 31, 2013, 11:09:13 AM »
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Bart, thank you for this valuable tool.

If you don't mind, I have a few questions related to macro photography,

1) Aperture: Should I use the equivalent aperture (adjusted for magnification) or the lens uncorrected aperture?
2) Focal length: in lenses with internal focusing, does it matter if the focal length varies at close range? Should I consider the adjusted focal length?
3) Can you recommend a procedure to determine pupil factor?
4) Focus stacking: are the steps the same regardless of the method to change focus between images? (Focus lens, change camera+lens position or moving the back only when using a bellows)

Hi Francisco,

Great questions! Hope you like the answers Wink

1) You use the regular Aperture that you've dialed in on the camera/lens. The equivalent aperture or effective aperture as it is called by some, is used to allow for an adjustment of the exposure time due to added lens extension.

Because the correction is usually executed by lengthening the exposure time, and not by opening up the aperture (which changes DOF), I've avoided mentioning 'effective aperture'. It tends to confuse, although many use it..

I make a separate mention of the effect on exposure in the comment behind 2.6.1), where both the (required) extension compared to infinity focus is mentioned, as well as the 'bellows factor' or required additional exposure. I've changed the latter from a simple multiplication factor to the number of EVs ('stops') that is required to achieve correct exposure, when it's not measured through the lens. That is mostly used to correct external light measuring and flashes, which cannot know how much extension was applied to achieve the required magnification. On flashes the power can often also be regulated by fixed (1/3rd, or other fractions of) EV amounts, or they are coupled automatically with the lightmetering system which measures through the lens.

2) We have no way of knowing the actual focal length, especially with Macro lenses with internal focusing groups of elements. They may reduce the focal length to allow closer focusing without the need for a longer lens tube/barrel. Therefore, the only result we can measure with certainty is the image magnification. That is also the most common way of dealing with macro issues. I know my EF 100mm f/2.8 II Macro uses internal focusing and extension, and my MP-E 65mm uses primarily, if not exclusively, extension.

So, whether the focal length is reduced, or the extension is effectively increased, we don't know, but the magnification is what will cause the exposure extension and the magnification of the blur/COC and diffraction effects. So in the end, it shouldn't matter much if the extension or the focal length changes, or both, as long as we know the magnification factor. It's usually indicated on a dedicated Macro lens, or simple to measure by focusing on something with known dimensions, such as a ruler or a coin, and compare that to the captured percentage of the sensor/film dimensions.

In Photomacrography, it is not reliable to measure it from the Focus distance used in lens formulae, including my tool, because we don't know the exact optical design and where that positions the optical primary and secondary principle planes.

So my recommendation is, enter the manufacturer's suggested focal length, and use the magnification factor to take care of all other effects.

3) The only procedure that's simple to execute is to look through the lens when not attached to the body, in front of a bright background. Hold it at arm's length and hold a ruler near the side facing you and measure the apparent diameter of the aperture. You measure the entrance pupil with the front of the lens facing you, and the exit pupil with that end of the lens facing you. The Exit (rear) diameter divided by the Entrance (front) diameter is the Pupil factor. It may, or may not, make some difference if the lens is focused at anything else than infinity, due to the internal focusing.

4) There is a difference between using (internal) lens focusing, which follows the magnification rules of my tool as you change the focus distance, and stepping the camera and lens together in a fixed setting on a focus rail. When focusing with the lens, one will need to use progressively larger steps as distance increases, or use the narrowest DOF zone and step through the scene with that (but that will require more slices than strictly needed).

When the focus rail method is used, which I prefer when things get really magnified a lot, like with the MP-E 65mm, then the magnification factor is also unchanged, and the DOF slice will be constant. So in that situation you just calculate the DOF of a given magnification factor, and use that as your fixed step increment.

There is another difference between the two methods, and that has to do with the amount of distance change of the entrance pupil relative to the subject. When the entrance pupil changes position, as is usually the case unless we use equipment which allow to only change the sensor plane position, the perspective changes as well. Dedicated stacking software will compensate by changing the slice magnification, but cannot deal with some of the occlusion effects and perspective shifts between foreground and background features. So, unless the DOF is extremely shallow, there may be stacking errors. Rik Littlefield has written an excellent article about that.

So, whenever lens focusing is used to step through the DOF zones, you can use my tool for guidance on step size and number of required steps, and when a focus rail is used with a fixed magnification factor, you can use my tool to determine that fixed DOF zone depth. It will be difficult to focus by measuring focus distance, because it is not obvious from where on the lens itself to measure, so some common sense needs to be applied, or the shallowest DOF slice distance should be used for all slices. It's better to have no gaps in a focus stack, so I'd err on the side of caution.

Cheers,
Bart
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FranciscoDisilvestro
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« Reply #33 on: September 01, 2013, 01:11:15 AM »
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Bart,

Thank you very much for your detailed responses. There is a potential issue for some cameras / lenses that use the "adjusted aperture" instead of the uncorrected aperture. For instance, some Nikon camera/lenses combinations use the adjusted aperture. There are also some models of Nikon manual micro lenses with "compensating" diaphragm, so it is important to be aware of this when entering the data in the application.

Regards,
 
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BartvanderWolf
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« Reply #34 on: September 01, 2013, 04:58:43 AM »
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Bart,

Thank you very much for your detailed responses. There is a potential issue for some cameras / lenses that use the "adjusted aperture" instead of the uncorrected aperture. For instance, some Nikon camera/lenses combinations use the adjusted aperture. There are also some models of Nikon manual micro lenses with "compensating" diaphragm, so it is important to be aware of this when entering the data in the application.

Hi Francisco,

Thanks for that. I didn't know that.

I also hate that, when camera's make decisions that influence image quality/characteristics without the user being able to allow or disallow that (unless it only reports the wrong/'corrected' aperture value). The physical aperture setting changes foreground/background blur characteristics and changes the diffraction pattern. That's not something a camera should decide on its own or suggest to be using, IMHO.

What they should have implemented, is an option to automatically adjust the exposure time as a function of the magnification factor (or focus distance, same difference), or a suggested increase of the exposure time, in case no through-the-lens exposure metering is possible.

So, in those cases where the camera/lens thinks it knows better, one needs to use the comment in my tool behind the magnification factor about +EV, and enter that as a wider aperture value in the tool when the camera/lens actually changes the aperture, or a narrower aperture when the camera only reports the wrong / 'corrected' value.

The DOF calculations in my tool use the actual physical aperture diameter that is used. The tool even uses more accurate values than the nominal ones, to make sure that an exact 1/3rd stop interval is used instead of rounded values. So, instead of calculating with 5.6 as suggested by the f/5.6 marking on the lens/camera, it uses 5.656854249492381 which is (save for floating point number limitations) exactly one stop narrower than f/4. That may also be the reason for tiny fractional differences in the results between this calculator and others one can find on the internet.

Cheers,
Bart
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Hening Bettermann
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« Reply #35 on: September 12, 2013, 02:30:01 PM »
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Hi Bart!

Another great tool from your hand - thank you!

Entering the values for my Canon 5D2, and an intended print size of 70x100 cm with a diagonal = viewing distance of 1.2 m, the tool shows me that I have enough resolution even for Higher Quality prints: Max 137.2x91.84 cm @ 104 PPI; 100 x 66.67 cm @ 142.6 PPI.

Does this mean that my efforts with SuperResolution are waisted?
Or can I exspect that the result of the following upsampling to the printer-native resolution will be better if there are twice as many pixels to begin with?

Kind regards - Hening

 
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BartvanderWolf
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« Reply #36 on: September 12, 2013, 03:36:59 PM »
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Hi Bart!

Another great tool from your hand - thank you!

Entering the values for my Canon 5D2, and an intended print size of 70x100 cm with a diagonal = viewing distance of 1.2 m, the tool shows me that I have enough resolution even for Higher Quality prints: Max 137.2x91.84 cm @ 104 PPI; 100 x 66.67 cm @ 142.6 PPI.

Does this mean that my efforts with SuperResolution are waisted?

Hi Hening,

At that viewing distance it may not be strictly needed, but at closer viewing distances, or for those with higher visual acuity, it still helps to have more resolution. This also assumes good illumination levels, because when the pupils of our eyes dilate too much (lens edge aberrations), visual acuity suffers, as it does when the pupils need to contract too much (diffraction). Veiling glare (loss of contrast) increases with age.

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Or can I expect that the result of the following upsampling to the printer-native resolution will be better if there are twice as many pixels to begin with?

The subsequent up-sampling to native printer resolution will be more accurate, but we won't be able to resolve that additional resolution with our eyes, until we move in closer.

However, one may be able and exploit the additional resolution by getting a higher quality deconvolution output sharpening. That will help the local contrast that we can resolve with our eyes, but it also depends on the subject. So for those who know what they are doing (and have the right tools), the resolution that cannot be resolved anymore by eye, can possibly still be put to some good use.

That's also why I recommend the use of Benvista's Photozoom Pro for up-sampling for large format output. Pixel peeping at display level it may look a bit artificial, but at the proper viewing distance it produces better viewing quality.

Cheers,
Bart
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Vladimirovich
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« Reply #37 on: September 12, 2013, 05:33:58 PM »
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Need this in an iPhone app 
what is iPhone ?
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Hening Bettermann
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« Reply #38 on: September 13, 2013, 05:10:35 AM »
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Hi Bart,

Thank you for your reply!

> However, one may be able and exploit the additional resolution by getting a higher quality deconvolution output sharpening.

I don't do the output sharpening myself, but leave that to my print service. However, I plan in the future to  *capture* sharpen *after* resampling to print size. I assume, this, too, might benefit from additional resolution?

All in all, however, what you write sounds like the benefits of SR for my preconditions are marginal, and when I get the time, I may try it out.

Kind regards - Hening.
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BartvanderWolf
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« Reply #39 on: September 13, 2013, 06:20:15 AM »
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Hi Bart,

Thank you for your reply!

> However, one may be able and exploit the additional resolution by getting a higher quality deconvolution output sharpening.

I don't do the output sharpening myself, but leave that to my print service. However, I plan in the future to  *capture* sharpen *after* resampling to print size. I assume, this, too, might benefit from additional resolution?

Hi Hening,

Yes, absolutely. It's unfortunate that we need to do this, but in many cases we can still produce better quality output by sending our homebrewed results for plain printing. Not all external parties master the necessary skills, tools, time, to up-sample and sharpen for output as it should be done.

A JPEG which was already converted to the output profile for the off-site printer usually suffices, because they can skip file modifications such as output sharpening and profile conversion. One needs to setup a line of communication with the people who do the printing, which may sometimes be difficult. I usually specify, print without alterations and without additional sharpening, and embed the profile to reduce the risk of double profiling.

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All in all, however, what you write sounds like the benefits of SR for my preconditions are marginal, and when I get the time, I may try it out.

Maybe, maybe not. It depends on how large one needs to go, but for many applications adding a bit of viewing distance in the equation can reduce the need for SR. It won't hurt to have the extra files for when it is needed, but you may be able to make that additional operation more exception than rule.

Good Capture sharpening and/or Output sharpening can help a lot, and using the best upsampling method can also make a difference. I hope my tool helps in planning the necessary steps to achieve the desired outcome.

Cheers,
Bart
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