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Author Topic: Helicon Remote Question  (Read 1990 times)

DeanChriss

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Helicon Remote Question
« on: May 16, 2015, 02:26:08 pm »

Does anyone here know if Helicon Remote can be used to determine whether a given aperture will give adequate DOF for a photo in a single exposure? For instance, if you set the aperture to f/8 and that provides adequate DOF for the entire scene (or the near and far points you set), will it set the proper focal distance and give a "stack" of 1 image? That would be more accurate than guessing distances and faster than using magnified live view at near and far points when focus stacking is not involved.
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PeterAit

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Re: Helicon Remote Question
« Reply #1 on: May 16, 2015, 04:36:49 pm »

I don't think so. It might not be possible because DOF is a subjective thing. There's one focus point and everything else is out of focus - but it may be out of focus to such a small extent that it makes no difference in the appearance of the final image. But an acceptable DOF on a 10MP camera might not be ok on a 50 mp camera.
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Bart_van_der_Wolf

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Re: Helicon Remote Question
« Reply #2 on: May 16, 2015, 04:57:10 pm »

Does anyone here know if Helicon Remote can be used to determine whether a given aperture will give adequate DOF for a photo in a single exposure? For instance, if you set the aperture to f/8 and that provides adequate DOF for the entire scene (or the near and far points you set), will it set the proper focal distance and give a "stack" of 1 image? That would be more accurate than guessing distances and faster than using magnified live view at near and far points when focus stacking is not involved.

Hi,

Helicon Remote can only calculate the number of focus steps that are required between two focus distance settings. If that difference corresponds to the DOF of the aperture, then a single exposure will be made. However, because DOF is usually less than one thinks, that will be a rare occasion. It obviously also depends on the COC one considers adequate for the intended output size and viewing distance.

Cheers,
Bart
« Last Edit: May 17, 2015, 04:39:45 am by BartvanderWolf »
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DeanChriss

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Re: Helicon Remote Question
« Reply #3 on: May 16, 2015, 11:25:21 pm »

Absent any input to the program regarding output size and the like, I suppose the program decides what is "in focus" based on the most stringent requirements, like being very close to a very large print. Because of that there will nearly always be multiple exposures involved.

Thanks, this is exactly what I needed to know.
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Bart_van_der_Wolf

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Re: Helicon Remote Question
« Reply #4 on: May 17, 2015, 04:51:21 am »

Absent any input to the program regarding output size and the like, I suppose the program decides what is "in focus" based on the most stringent requirements, like being very close to a very large print. Because of that there will nearly always be multiple exposures involved.

Not necessarily. It uses sensor size (and a COC assumption), focal length, aperture, and focus distance to calculate the DOF for a single image. It then figures out how many focus steps it takes to go from front to rear of the indicated A-B focus range. It then calculates the number of focus steps there are in the DOF for a single image, and divides the total by that. It then also uses the user's correction factor input to modify that number. That then leads to the number of images, and focus steps between the images if there are more than one.

Cheers,
Bart
« Last Edit: May 17, 2015, 09:50:53 am by BartvanderWolf »
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DeanChriss

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Re: Helicon Remote Question
« Reply #5 on: May 17, 2015, 07:02:45 am »

Not necessarily. It uses sensor size (and a COC assumption), focal length, aperture, and focus distance to calculate the DOF for a single image. It then figures out how many focus steps it takes to go from front to rear of the indicated A-B focus range. It then calculates the number of focus steps there are in the DOF for a single image, and divides the total by that. It then also user the user's correction factor input to modify that number. That then leads to the number of images, and focus steps between the images if there are more than one.

Cheers,
Bart

Thanks very much for that clarification, Bart.
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dwswager

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Re: Helicon Remote Question
« Reply #6 on: May 17, 2015, 10:54:25 am »

Does anyone here know if Helicon Remote can be used to determine whether a given aperture will give adequate DOF for a photo in a single exposure? For instance, if you set the aperture to f/8 and that provides adequate DOF for the entire scene (or the near and far points you set), will it set the proper focal distance and give a "stack" of 1 image? That would be more accurate than guessing distances and faster than using magnified live view at near and far points when focus stacking is not involved.

Obviously, DOF depend on the final enlargement.  Hence you have to know the output and select a CoC that gives the required DOF for that output. 

That said, there is way to show based on the current f stop and focus point what is in focus based on the parameters Helicon remote is using.  I own, but have not used the desktop version a lot, but in the Android version it shows blue blinkies overlaid what is in focus.

Just opended the desktop version and there are 2 check boxes that affect the live view.  First is for Canon cameras only and gives a DOF Preview.  The second one is FOCUSED and I believe that is what turns the blue blinkies on in the live view.  I've played with this some changing the focal length of my lens and the aperture and I was able to see that the entire image was within what Helicon though was acceptable DOF.

In addition, the desktop (not sure about the Android version at this point) has a Hyperfocal calculator that looks like the photo attached.
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DeanChriss

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Re: Helicon Remote Question
« Reply #7 on: May 18, 2015, 06:39:15 am »

..., but in the Android version it shows blue blinkies overlaid what is in focus.

That would seem to make Helicon Focus useful as a single exposure focusing tool, in addition to the focus stacking features. Thanks!
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