Is there a Depth of Field calculator?? Maybe?

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shaypivac
Posts: 13
Joined: Sat Oct 06, 2018 5:44 pm
Location: Australia

Is there a Depth of Field calculator?? Maybe?

Post by shaypivac »

Sorry I tried searching, but to no avail.

But is there a general rule of thumb to what Um to shoot at? Like maybe 40Um for a 5mm specimen? Maybe like a depth of field kind of thing?

I'm shooting up to 5X at this stage with a Sony a6300 + Laowa 25mm 2.5-5X. (Sweet spot is f/4 as I've found)

For example I've tested on a fly, with just the face. And don't see much difference between 15Um and 40Um.

I'm not the most technically advanced photographer, but I have been shooting around 7years, so I do know a bit, just never bothered with the technical stuff lol

But the majority had been landscape and architecture where you just play with f-stop and maybe max 3 focus stacked images.

Any links regarding this?

Pau
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Post by Pau »

Take a look at this recent thread on the subject:
http://www.photomacrography.net/forum/v ... 647#238647
Pau

shaypivac
Posts: 13
Joined: Sat Oct 06, 2018 5:44 pm
Location: Australia

Post by shaypivac »

sorry, no idea what any of that means :/

I wouldn't even know what * stands for? :/

But thanks for trying

Chris S.
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Post by Chris S. »

Shay,

In answer to your specific question, the asterisk sign (“*”) is used, in this instance, as the math symbol for "multiplied by". For example, “A = B * C” is shorthand for “A equals B times C”. However, you can safely ignore all formulas and get the information you need without using mathematics, by simply looking at a chart.

Take a look at Table 2A in Rik Littlefield's DOF Estimates For Macro/Micro. While this is a portion of the supporting documentation for Rik's Zerene Stacker software, it is applicable to any macro shooting with the sort of lens you're talking about. Also read the couple of paragraphs above table 2A, which explain how to use it.

Your Sony a6300 has an APS-C sensor, so as those paragraphs explain, you want to look at the stacking increments near the center of the boldfaced values. At nominal f/4 and 2x, this means 0.079 mm (79 microns). At nominal f/2.8 and 5x, this means 0.025 mm (25 microns).

Be aware that there is room for using either larger or smaller stepping increments than these specific numbers. The values in table 2A are good, safe ones to start with. As you gain experience, and if you care to do additional testing, you may find reason to choose different values. For example, with excellent equipment and technique, for big prints, you might find that increments about half the suggested size give you a bit more contrast in fine detail. If you have a rapidly wilting specimen or will be downsizing for Web use, you might choose a larger increment to save time. But Table 2A is a great place to start.

--Chris S.

shaypivac
Posts: 13
Joined: Sat Oct 06, 2018 5:44 pm
Location: Australia

Post by shaypivac »

Chris S. wrote:Shay,

In answer to your specific question, the asterisk sign (“*”) is used, in this instance, as the math symbol for "multiplied by". For example, “A = B * C” is shorthand for “A equals B times C”. However, you can safely ignore all formulas and get the information you need without using mathematics, by simply looking at a chart.

Take a look at Table 2A in Rik Littlefield's DOF Estimates For Macro/Micro. While this is a portion of the supporting documentation for Rik's Zerene Stacker software, it is applicable to any macro shooting with the sort of lens you're talking about. Also read the couple of paragraphs above table 2A, which explain how to use it.

Your Sony a6300 has an APS-C sensor, so as those paragraphs explain, you want to look at the stacking increments near the center of the boldfaced values. At nominal f/4 and 2x, this means 0.079 mm (79 microns). At nominal f/2.8 and 5x, this means 0.025 mm (25 microns).

Be aware that there is room for using either larger or smaller stepping increments than these specific numbers. The values in table 2A are good, safe ones to start with. As you gain experience, and if you care to do additional testing, you may find reason to choose different values. For example, with excellent equipment and technique, for big prints, you might find that increments about half the suggested size give you a bit more contrast in fine detail. If you have a rapidly wilting specimen or will be downsizing for Web use, you might choose a larger increment to save time. But Table 2A is a great place to start.

--Chris S.
Thank you. That's very understandable lol I only just passed my maths at college so that could be the issue :/

johan
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Contact:

Post by johan »

Hi, some other calculators here

http://extreme-macro.co.uk/calculators/

also cambridge in colour forum had one last time I looked
My extreme-macro.co.uk site, a learning site. Your comments and input there would be gratefully appreciated.

ploum
Posts: 256
Joined: Sat Oct 18, 2014 6:35 am
Location: France

Post by ploum »

Mine is here.... In french
http://www.alpinismeetmineraux.fr/miner ... ro/pdc.ods

Open document
I work with a manfrotto 454 but uncommon system :).
Objectives : BW APO PLAN 5x, Mitutoyo APO PLAN 7.5x, 10x, 20x and 50x, Seiwa APO PLAN 20x, BW APO PLAN 20x, Seiwa APO PLAN 10x, Nikon CF PLAN 50x, componon APO 40 mm, Componon 50 mm, Componon S 80 mm, Componon 105 mm, Componon 150 mm, Rodagon 135 mm.....

Yawns
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Location: Benavente, Portugal

Post by Yawns »

ploum wrote:Mine is here.... In french
http://www.alpinismeetmineraux.fr/miner ... ro/pdc.ods

Open document
you'r is password protected ...
YAWNS _ (Y)et (A)nother (W)onderful (N)ewbie (S)hooting

ChrisR
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Location: Near London, UK

Post by ChrisR »

It opens in LibreOffice :)
Chris R

clarnibass
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Joined: Fri Jun 10, 2016 11:33 pm

Post by clarnibass »

I mostly use the calculators in johan's link and IME they are accurate. I use the step size and extension ones the most.

I think you are asking about step size, right? This is directly to that calculator: http://extreme-macro.co.uk/focus-stacking/#calculator

You enter the F number, magnification and type of sensor and it gives you the step size. I'm guessing the sensor size is only relevant because they assume you e.g. print the same size at the end i.e. you actually magnify higher with the smaller sensor.

For your example, with the Sony A6300, f/4 and x5 magnification, it says minimum step is 0.033mm (33um). So 15um probably gave redundant steps, and maybe 40um was just close enough to barely notice a difference, if at all.

All the parameters could be slightly different that it's actually not x5 at f/4 on the camera (just as a random example, sensor size might be slightly different, lens, aperture, etc.).

Also AFAIK those calculators also assume some kind of result size. I mean, take a huge blurry photo, make it tiny, it looks sharp. If you view at a smaller size then an even larger step might look similar.

Ulrik Tønnesen
Posts: 16
Joined: Thu Nov 22, 2018 7:35 am
Location: Denmark

Post by Ulrik Tønnesen »

I came around an android app called Macro Tools, it got the following features:
- Focus Stacking Step Size
- NA to Fstop
- Infinite Objective Focal Length
- Extension Tubes Magnification
- Bellows Magnification
- Reverse Lens
- Raynox Adapter
- Closeup Lens
- Stacked Lens Magnification

It's free but contains ads, which can be removed by getting the PRO version, it's 2 bucks or whatever.

I suggest you give it a look :P
https://play.google.com/store/apps/deta ... ulator.pro

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