photo of the day

well here the group of yellow pyroclore of 0.26 mm into a cavity, files are not worked, in the first is normaly format, in the second its a cut and a crop of the group, not worked the same





the end work is here [www.mindat.org]

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Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

Matteo the size is big, resolution is low. Have you a photo to compare with the last like béraunite. I prepare a photo with 0.35 mm of fov and 0.05 mm for cristal.

Thanks.

0.05 mm I do not waste time even seen a photo with similar sizes that would be horrible, and its SEM material

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Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

Matteo i prepare this photo and she is not horrible.... If you can't, i understand. The Beraunite is not horrible, she is limited by diffraction and in fact she is very good for the size...

Tonight i give this photo with 0.35 mm of fov and not horrible... I make compilation.

Matteo,
Between which points do you measure the 0.26 mm ? Is it the largest distance across the group, or the length of the edge of one of the crystals ?
FOV is less ambiguous.
best regards,
Dominik

The question is interessant Dominik !

I prefer FOV...

Dominik Schläfli Wrote:
-------------------------------------------------------
> Matteo,
> Between which points do you measure the 0.26 mm ?
> Is it the largest distance across the group, or
> the length of the edge of one of the crystals ?
> FOV is less ambiguous.
> best regards,
> Dominik


normaly I use electronic caliper with lens, for others I use the ocular micrometer of the microscope. I take the measure from a corner to corner for the group, type here, or of the single crystal when possible

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Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

another question on different cameras, here a wulfenite of Rowley Mine of 7.14 mm. The first is take in the 12/12/2008 with Canon 40D the second take today 18/12/2011 with Canon 5D mark II, same file size worked the definition its many different



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Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

First photo one other with a statistic method come after. In fact i search something...

I like this photo like a MEB...

OK, then the field of view of your first photo is about 1.4 mm, and 0.5 mm for the second.

I take same quality and perhaps better with simple close-up Matteo....

friendly

Fred



Edited 1 time(s). Last edit at 12/18/2011 09:42PM by Frédéric Hède.

Yes exactly 1.4 mm for Matteo and my photo is very far of this size i can made photo for compare but for the moment i study for 0.35 mm of FOV.

Frédéric Hède Wrote:
-------------------------------------------------------
> Yes exactly 1.4 mm for Matteo and my photo is very
> far of this size i can made photo for compare but
> for the moment i study for 0.35 mm of FOV.

ok, but it will be unusable for publications, in my case for similar measure the reviews use SEM photos

Mindat Page

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Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

Frédéric Hède Wrote:
-------------------------------------------------------
> I take same quality and perhaps better with simple
> close-up Matteo....
>
> friendly
>
> Fred


depend how many is possible for you cut the photo, with full frame I cut how many times I want with no lost of resolution, if I cut the photo take with 40D I lost the resolution immediatly

Mindat Page

[www.mindat.org]


Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

But here we can seen color (incredible yellow), and she is translucid too.... Not the same thing.... I prefer that....

And here it's just for fun, in 1.4 mm of FOV i can give much more than you i think... Send me if you want :)

Friendly

Fred

For me it's simple, i don't cut.... Why ? I can built a photo between infini and 0.31 mm of fov....

an another photo come after, first try with statistic method....


=> No significative difference.



Edited 1 time(s). Last edit at 12/18/2011 10:35PM by Frédéric Hède.

Frédéric Hède Wrote:
-------------------------------------------------------
> Matteo i prepare this photo and she is not
> horrible.... If you can't, i understand. The
> Beraunite is not horrible, she is limited by
> diffraction and in fact she is very good for the
> size...


Fred, I think diffraction is the minor problem in this photo. I can see focus banding, i.e., the stepping increments are too large - not enough overlap. What is the numerical aperture of your 20X objective? Usually, 20X objectives have a DOF of a little more than 2 microns, that means you would need stepping increments of less than 2 microns. Also, the quality of that lens looks a bit soft to me.
Cheers

Harry



Edited 1 time(s). Last edit at 12/19/2011 05:48AM by Harald Schillhammer.

Matteo Chinellato Wrote:
-------------------------------------------------------
> well here the group of yellow pyroclore of 0.26 mm
> into a cavity, files are not worked, in the first
> is normaly format, in the second its a cut and a
> crop of the group, not worked the same
>
> [s02.imageupper.com]
> _2.jpg
>
> [s02.imageupper.com]
> _1.jpg
>
> the end work is here
> [www.mindat.org]


Matteo, these photos clearly show the limitations of Luminars and Photars. For this subject size, you would probably take a 12.5 Photar at full bellows extension. Even when used with completely open aperture, the effective aperture is way beyond the diffraction limit. In addition, the working distance is so small that lighting becomes a problem. For this subject size I would choose a 40X objective and if you take a ELWD version you still have substantially more working distance than with a Photar. However, at this magnification one has to be extremely careful to avoid even the slightest vibration. As a Canon user, you have at least the advantage of the silent mode which mitigates the problems caused by mirror slap and shutter curtain. But even a car passing outside the house might have negative influence on the quality :). I think with microscope objectives you may achieve acceptable print quality down to a FOV of about 0.1 mm, given you have an absolutely vibration-free set-up. Anything smaller than that I guess SEM is the only serious option.
Cheers

Harry

Harald Schillhammer Wrote:
-------------------------------------------------------
> Matteo Chinellato Wrote:
> --------------------------------------------------
> -----
> > well here the group of yellow pyroclore of 0.26
> mm
> > into a cavity, files are not worked, in the
> first
> > is normaly format, in the second its a cut and
> a
> > crop of the group, not worked the same
> >
> >
> [s02.imageupper.com]
>
> > _2.jpg
> >
> >
> [s02.imageupper.com]
>
> > _1.jpg
> >
> > the end work is here
> > [www.mindat.org]
>
>
> Matteo, these photos clearly show the limitations
> of Luminars and Photars. For this subject size,
> you would probably take a 12.5 Photar at full
> bellows extension. Even when used with completely
> open aperture, the effective aperture is way
> beyond the diffraction limit. In addition, the
> working distance is so small that lighting becomes
> a problem. For this subject size I would choose a
> 40X objective and if you take a ELWD version you
> still have substantially more working distance
> than with a Photar. However, at this magnification
> one has to be extremely careful to avoid even the
> slightest vibration. As a Canon user, you have at
> least the advantage of the silent mode which
> mitigates the problems caused by mirror slap and
> shutter curtain. But even a car passing outside
> the house might have negative influence on the
> quality :). I think with microscope objectives you
> may achieve acceptable print quality down to a FOV
> of about 0.1 mm, given you have an absolutely
> vibration-free set-up. Anything smaller than that
> I guess SEM is the only serious option.
> Cheers


I use everytime the live view of the camera, the problem is moving the bellow with hands, when I have extra money I buy the computed micrometer slide just for not tuch the bellow. But similar photos its for me, and other photographers, only for SEM

Mindat Page

[www.mindat.org]


Attrezzatura e tecnica sono solo l'inizio. È il fotografo che conta più di tutto. (John Hedgecoe)

Hello,

hum the increment is normally good i can make more if i want, i can try better. In fact my system have no limitation as classic system and the maximal precision is 0.1 µm or less....

Ok i try more.... But i think tan the limitation is just diffraction.



Edited 1 time(s). Last edit at 12/19/2011 06:49AM by Frédéric Hède.