Going beyond 90mm for Macrophotography

[ajohnw]

John needs to try a 24mm or maybe 20-22mm lens backward on his bellows Grahame.

Trouble with your pen idea is how to take the format size out of it. While I have no stacking software up and running and would need it I could easily fill m 4/3 with the end of a ball point pen. Ideally I would also need some adapters but apart from stacking software might still be able to do it.

I've been trying to think of something to try some fairly normal macro gear out on but hoped for something with more detail than a pen. No idea how well this gear will work but I could give it a go to find out.

John
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[AlwaysOnAuto]

I've been following this thread with interest.
It inspired me to get my camera out and try a few shots.
Here's what I came up with after reading the post about the pen.
Don't mean to high jack the thread and I know my feeble attempt at an image isn't nearly as good as what you fella's are talking about, but I thought you'd like to know your efforts aren't falling on deaf ears.



Taken with my NEX 7 w/30mm LTM extension tube and Canon 35mm F3.5 lens.
Thanks for looking, carry on.

[IzzieK]

Good idea, but I guess I will pass because I am not a boy.

[ajohnw]

Good idea, but I guess I will pass because I am not a boy.

LOL I assumed your avatar was a photo of a female friend or such like Izzie. I'm sure ladies would be welcome. It's just that some expressions are some what gender specific.

John
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[IzzieK]

Oh. OK...got it.

[Stagecoach]

Good idea, but I guess I will pass because I am not a boy.

I apologise profusely Izzie, I should have said adults

[Stagecoach]

Trouble with your pen idea is how to take the format size out of it.

The manufacturer only specifies a 1200 px wide image. The format is of no consequence

While I have no stacking software up and running and would need it

Has the manufacture specifically mentioned DoF? If you consider you can please him by producing a stacked image that is your choice

The manufacturer may have the view that a stacked image is simply demonstrating your stacking skills

I could easily fill m 4/3 with the end of a ball point pen. Ideally I would also need some adapters but apart from stacking software might still be able to do it
John
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The manufacture is looking for a quality image
The manufacture will weight his assessment marking partly on the size of the subject filling the frame

Grahame

[jcuknz]

Sorry Stagecoach but I object to 1200 pixels as I always reduce my images to 800 pixels or less

[Stagecoach]

Sorry Stagecoach but I object to 1200 pixels as I always reduce my images to 800 pixels or less

That's ok John, I'll still have a go as I need the money he may pay if I can meet his requirements

[Stagecoach]

The end of my biro.



Unropped with basic PP downsized to 1200px width.
23.6mm sensor, 105mm macro, 68mm tubes, reversed 50mm and a lot of patience getting focus in the place I wanted.

Grahame

[ajohnw]

Sorry Stagecoach but I object to 1200 pixels as I always reduce my images to 800 pixels or less

800px is cheating. I rate my gear on the basis of being able to post a 100% crop as per the fly earlier.

On a serious note I take shots when I can see the detail I want in the viewfinder and don't worry about magnification. It has a catch and the fly is a good example. To show the detail in it I have to post a 100% crop. At the sensor pixel level DOF is usually severely limited so if I had used more magnification and reduced chances are I would have had more depth of field. Something to sort out more next year when there are plenty of insects about again. Not sure what will happens so best thing is to try it and find out.

Off to find a biro and get the gear out. I'll just post what I get.

John
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[george013]

Reading this thread and not being a macro-photographer, I wonder that the used f-numbers are not mentioned.
On one hand a high f-number gives a deeper DOF, but on the other hand more negative influence due to diffraction. Especially when using macro.

George

[ajohnw]

Reading this thread and not being a macro-photographer, I wonder that the used f-numbers are not mentioned.
On one hand a high f-number gives a deeper DOF, but on the other hand more negative influence due to diffraction. Especially when using macro.

George

One of the reasons many people post images on here rather than links to some where else is that it retains exif information so if you right click on them and select properties the basic info is available. That can be very helpful when some one is having problems.

You might find some have the exif removed but many will have it.

John
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[george013]

One of the reasons many people post images on here rather than links to some where else is that it retains exif information so if you right click on them and select properties the basic info is available. That can be very helpful when some one is having problems.

You might find some have the exif removed but many will have it.

John
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I know how to read the exif. I just wonder that the f-number is not mentioned as a varaible that also has influence on the photo quality.
The last photo, of Stagecoach, is shot with a D300 and f18.
Given a subject on infinity, that would give a airy disk of 0.0213mm. But if you do macro at a magnification of 1, your working f-number will be f36, giving an airy disk of 0.0426mm. Twice as big as the CoC used here. https://www.cambridgeincolour.com/tu...hotography.htm

George

[ajohnw]

I know how to read the exif. I just wonder that the f-number is not mentioned as a varaible that also has influence on the photo quality.
The last photo, of Stagecoach, is shot with a D300 and f18.
Given a subject on infinity, that would give a airy disk of 0.0213mm. But if you do macro at a magnification of 1, your working f-number will be f36, giving an airy disk of 0.0426mm. Twice as big as the CoC used here. https://www.cambridgeincolour.com/tu...hotography.htm

George

I don't want to pollute this thread with comments on diffraction and camera lenses. Camera lenses are more a matter of circles of confusion size not just diffraction effects. They are compromises. All optical systems with many elements are and the only way of improving that aspect is reduction in size - eg microscope objectives but manufacturers freely admit that these in real terms aren't anyway in practical use for a number of reasons. Where diffraction has an effect eg Rayleigh's limit contrast is so low that is of no use to photography anyway.

John
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[ajohnw]

I need to find better lighting - not something I have bothered with for indoor use. Anyway. as per spec - minimal pp due to lighting and then reduction. Olympus macro lens at close to 1:1. Manual focus with 10x live view on the ball joint.



Same image 100% res crop.



Why didn't I knock back the iso from 800. Don't think a longer exposure would hurt.

John
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[ajohnw]

Take 2. Lighting somewhat better.

1:1 Olympus 60mm macro at F16 this time



Full res crop.



And Sigma 90mm macro at 1:1 plus the weaker Raynox clip on lens at F22. Reduced the focus distance but not made much difference to magnification.



John
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[george013]

Take 2. Lighting somewhat better.

1:1 Olympus 60mm macro at F16 this time



Full res crop.



And Sigma 90mm macro at 1:1 plus the weaker Raynox clip on lens at F22. Reduced the focus distance but not made much difference to magnification.



John
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John,
Could you make an exactly same one with f5.6 for comparisation?

George

[xpatUSA]

The last photo, of Stagecoach, is shot with a D300 and f18.
Given a subject on infinity, that would give a airy disk of 0.0213mm [diameter].
George

It's "Airy" not "airy". Airy was a person, see https://en.wikipedia.org/wiki/George_Biddell_Airy

Since the shot was mostly of a gray-scale subject, what lambda did you use in your calculation? (beware of the trap *).

It matters little to Stagecoach, I suspect, because he is certainly not shooting at infinite focus, eh?

* I claim that the image of a gray (neutral colored) point source is a blur spot, not an Airy disk, i.e. a blur spot consisting of an infinite number of disks between, say, 450 and 650nm, all overlaid

[ajohnw]

I have already posted F5.6 George. When people talk about diffraction they are inclined to forget that the rings play a part and more so with optical errors as the dark bands get lighter. This is why contrast drops off with increasing resolution - simply put. A sensibly quality level in wave front errors was set by Rayleigh - 1/4 wave. What you might not realise is that limit can simply be caused by the path lengths of "light rays" drawn in a typical ray trace diagram. Also the distance through glass is it's actual distance times it's refractive index. Things get seriously not diffraction limited even with only 1/2 wave error. Take umpteen pieces of glass and stick them in various places, hot press some etc and there is no chance of getting down to this sort of limit. And as I mentioned at Rayliegh's limit contrast is low - about 8% of what it should be from memory. In practice it wouldn't surprise me if camera lenses were still not diffraction limited at F22. The spots of course are also bigger in red and smaller in blue.

As I was curious about the gear I normally use - not the macro lens, I took some using the 75-300mm plus sigma achro close up lens. Taken set at about 260mm. The lens is past it's best at that but the shot was taken from around 400mm. Big advantage.



and the crop



I have no explanation for the yellow is line. I suspect it must be a hair. I did do a bit of very casual noise reduction on the background but that hasn't caused that. The astute will spot that elsewhere. Left in to illustrate the point.

Had hoped to try my latest close up lens acquisition but bought the wrong step up ring. I can try the clip on Raynox on it but it's seriously under diameter for the lens.

John
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