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daveg

Stacking

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That looks very good, but for a moment I thought your Gibson was a Bass. I could only see 4 tuners. Then I looked more carefully to see it isn’t, but the tuners furthest away don’t seem to line up with the posts the strings are on.

 

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My Epiphone is a guitar. I detuned a couple of strings because of highlights and that might cause what you see. But everything lines up correctly. Softer lighting needed.

If you look Very carefully there are a couple of spots which tend to indicate that a closer step width is required which will mean 70-100 images for this project and or using f8/f11.

It could be that PS is to blame but I will stick with it for a while - time is at a premium so I do not want to spend it learning new software.

At the spots where I see problems the individual images are great but PS has not masked it correctly. So, more shots closer together at f8 should help.

It's a learning curve.

DG

 

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You focus on the nearest point, or just closer.

You then set the number of shots and step width. It creates a new folder on your xqd card and numbers from 0001 or continues normal numbering. Set Silent Shutter.

Press the button and it takes the set number of shots at the set step width moving the focus automatically. If using Flash you need to set the Interval between shots to allow for re-charging. If focus reaches infinity at your settings it stops.

There are some charts in one of the links I provided earlier but I think that each shot will involve a certain amount of trial and error. Freshly charged batteries are essential.

DG

P.S. Does not work with older screw driven lenses. Newer G lenses are required.

 

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Depends on the size of the insect I suppose, but I will probably not go there for a while unless something to good to miss crops up.

Finding subjects without going outdoors is not going to be easy but I will try my best.

I get to do the shopping once a week so maybe I can find some interesting vegetables in M&S 😀

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Thanks for posting your stacked images Dave. I bought one of those rails last year at little expense off the internet with the intention of having a go at stacking some macro images. Your results are quite inspiring but confess the thought of coping with 70-100 images is a bit off putting!

Impressed though with the results you are getting.

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Hi Joan,

It is daunting if you use a focussing rail! But using the Z6/7 or D850 or a similar camera with focus shifting it takes the drudgery out of the taking stage.

Just set it up for the number of shots and step width and Press the button then step away. If you can use continuous lighting then the camera will take up to 300 shots shifting the focus by minute amounts automatically and silently. If you use flash then you have to allow for recharging and silent mode is not possible. I used flash here but I have tried ambient and silent mode and it is fast and silent.

The problems arise during the processing and depend on the step width being "right". It appears that all software requires a certain amount of "tidying up" after stacking and currently I am using Photoshop CC. Reviews I have read claim that Serene Stacker makes the tidying up very easy and when I have the time I will try their 30 day free trial. The big advantage of PS is that it will stack RAW files.

DG

 

 

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In normal circumstances, like a panorama for example. I would say that being able to stitch the images into a raw file is invaluable and it has made panos and HDR, far more acceptable.

With close up and tabletop photography would we say the same thing? There, the light is more under our control, so could you forgo the stitch to raw under those circumstances?

What do you think?

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If you can get enough depth of focus at the optimum aperture for the lens then there is no need for Focus Shift.

If you want front to back critical focus on an object (such as the guitar head example) then you are not going to get it and stay within the optimum parameters of the lens. If you go into more challenging subjects like tiny insects then it is even more of a problem.

It would probably be worth trying the shell example at different apertures just to see exactly what my 105mm micro will do if pushed to the limits. 

The way that I understand it, if we rely on the aperture to control the dof then we are going to get "acceptable" sharpness at the limits of the dof. What focus stacking does is give you "critical" sharpness between the two points that you set and does it at the optimum aperture of the lens (not the minimum aperture).

You raise a very interesting point.

At what stage does Focus Stacking become the only option?

BTW, I learned this week that the script which adds images to layers will operate on RAW files without the need for ACR conversions. Maybe it has always done this - I have never had the need to try it out before. 

If anyone wants to add anything to this please feel free to jump in.

DG

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A couple of follow up points to the last post above.

1. I tried a series of exposures of the Shell at the same sort of magnification as the one I posted above. By focusing on a point which was "sort of one third" into the shell and taking a series of exposures from f32 to f4 I was able to determine that I would not be able to acquire front to back focus (mainly back) even at f32.

2. At f8-11 I could get critically sharp focus on the nearest and furthest parts of the shell but then, in each case, the opposite side was wildly out of focus. 

3. So, for this subject and the view I chose, Stacking would give me critically sharp focus from front to back assuming that I chose the optimum number of images and step width.

DG

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I don't know what it is about the 105 when the aperture is at f32 or even f45 that, even then, you cannot get all of a small subject in focus. I read that it is something about being a macro lens and the way it works, that allows such apertures, but not the expected dof. Of course standing further away from the subject will help, but that sort of defeats the object of macro and getting close. Something like the Canon MPE 65 maybe more useful having 1 to 5 times magnification.

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23 minutes ago, Tinion 45 said:

I don't know what it is about the 105 when the aperture is at f32 or even f45 that, even then, you cannot get all of a small subject in focus. I read that it is something about being a macro lens and the way it works, that allows such apertures, but not the expected dof. Of course standing further away from the subject will help, but that sort of defeats the object of macro and getting close. Something like the Canon MPE 65 maybe more useful having 1 to 5 times magnification.

I have seen some excellent images taken with that lens but am I correct in thinking that, at those magnifications, the dof would be even less?

I was trying to answer the question posed by Barry and his suggestion that, because in a studio, we have complete control of lighting etc that stacking is not required. 

I agree that if you pose the object to suit the technical limitations then, yes, it can be done. But if you take as an example the head of the guitar the way I posed it then the assistance of stacking is needed to get the dof at the optimum aperture and even the manufacturers and certainly the reviewers of these lenses admit that f22-32 is not optimum.

DG

 

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I agree that if you need to focus stack you may as well use the optimum aperture of the lens to get the best quality image, thus avoiding diffraction. I've lost count of the number of times a judge has said not quite all of the subject is in focus or not on the plane of focus when referring to obvious macro taken images. Obviously that's why focus stacking came about. In the case of your guitar then finding that  unusual angle makes the image more intriguing, but doing so does not give you the obvious plane of focus or the easily possible dof.

Nice job on the shell Dave,

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