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Camera Talk / Re: DIY D7200 shutter replacement + insights
« Last post by mxbianco on Today at 09:52:40 »
Titanium shutter: same as the Nikon F,. except for the first 1000 samples (extremely rare, from sn 6400001 up to sn 6401000), which had a cloth curtain. On the Nikon F, shutter curtain travelled horizontally, and flash sync was limited to 1/60", while on the F2 it travelled vertically (and sync was upped to 1/125"). I'll have to dig out an F2 to make sure... [EDIT: it travels horizontally on the F and F2, on Nikkorex and F3 it travels vertically and it's similar to current venetian-type shutter ]

Bernard, I confirm that the shutter curtains were thin enough to be rolled up in spools at the sides of the frame. Second curtain would unroll to cover the frame at the appropriate time, and at shutter speeds below 1/60" the whole frame would be exposed to light.

As an added bonus, including here an excerpt from my own Nikon F Identification Scheme (my own research, which predates heavily -and adds a little something- on the top work by Richard DeStoutz)

Ciao from Massimo
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Camera Talk / Re: DIY D7200 shutter replacement + insights
« Last post by Bernard Delley on Today at 09:44:33 »
The camera inside looks like very cheap electronics. A lot of plastic, thin metal, self cutting screws that cuts into plastic etc. etc.
A F2 does not look that bad inside? :-)

The F2 has a titanium curtain that would not melt. The one in my F2 shows telltale marks on the curtain without any ill effect.

The electronic boards look like quality boards to me, definitely not the cheap brown hard-paper boards. The Faraday screening does not need to be thick metal. It is a mostly plastic construction with appropriate screws; good for weight. The plastic engineering appears to be state of this art, not prone to the rapid embrittlement as in cheap plastic toys. What I disliked the most was the soldering on edge for the shutter ribbon.

The F2 shutter is very thin titanium. The camera geometry of this horizontally running shutter seems to imply that it is rolled. I would not want to expose this shutter to focused sun light either.
The modern vertical running shutters are descendants of a shutter appearing first in the Nikkormat camera nearly contemporary with the F2. The blades are obviously very thin, surely titanium again. maybe a little thicker, as the must not bend and hold up for hundred thousands of actuations.

Fortunately, these shutters are protected by the mirror most of the time! Canon used a black cloth shutter in F2 times, if I recall right.
 
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indeed, the AF-S 105mm f/1.4 is a nice example of filed curvature. The mild decenterings and higher order aberrations mask things somewhat at f/1.4. stopped down it is quite clear, with the most clear perhaps at f/2.8: maximum micro contrast happens at the center at about 32mm front focus. At about 32mm back focus you find maximum micro contrast far out in the image field. The achievement for this lens design is that meridional and sagittal maps track almost perfectly, thus there is negligible astigmatism ! As the field curvature in object space goes towards the back far out in the image field, it is interesting to realized that the curvature of field at the sensor side is opposite, concave towards the lens. Because of the imaging ratio ~ sqrt(1000) it is that the 32mm in the object side translate to 32 micrometers at the sensor side.

It is also interesting to look again at the comparison of radial MTF traces, which I attached before.  The MTF from Nikon shows quite a dimple at the center. This means that the focus was chosen a bit to the backfocus side to even out MTF radially. MTF stays quite high nevertheless. Also the separation of meridional and sagittal in the Nikon MTF is symptomatic for minor residual astigmatism.

This and other things, like longitudinal color aberration, defocus control in MTF etc,  are discussed in the supplementary material linked in my opening post.
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Lovely portrait of a lady and her Nikon Z fc :)

Reflected light into the scene does reduce the harsh contrast for the better of the whole.
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Quick snapshot of the better half while shooting under an old train bridge in the desert near Socorro, New Mexico, USA yesterday. The reflected light seemed right even in the harsh midday sunlight. Nikon Z7ii 105mm F4, ISO 64, 1/250s.


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Camera Talk / Re: DIY D7200 shutter replacement + insights
« Last post by Øivind Tøien on Today at 00:53:47 »
The camera inside looks like very cheap electronics. A lot of plastic, thin metal, self cutting screws that cuts into plastic etc. etc.
A F2 does not look that bad inside? :-)

The F2 has a titanium curtain that would not melt. The one in my F2 shows telltale marks on the curtain without any ill effect.
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Camera Talk / Re: DIY D7200 shutter replacement + insights
« Last post by MEPER on Today at 00:01:17 »
The camera inside looks like very cheap electronics. A lot of plastic, thin metal, self cutting screws that cuts into plastic etc. etc.
A F2 does not look that bad inside? :-)
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What the Nerds Do / Re: Measuring Lens "Sharpness" across the image field: MTF
« Last post by MEPER on March 24, 2023, 23:46:19 »
With this you can get an "image" of the focus plane if plane is not flat field?
Many vintage lenses have a bit of field curvature?
As I remember a lens like the Nikkor-H 50/2 if you focus at center then the corners are sharp at a closer distance.
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Themes, Portfolio Series, PaW, or PaM / Re: [Theme] minimalist images
« Last post by golunvolo on March 24, 2023, 22:58:54 »
Last image I shot today. Both with D850 and 105 1.4e. Marvellous combo. I still have minimalism as my most common way to get close to the subject, I think.
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Themes, Portfolio Series, PaW, or PaM / Re: [Theme] minimalist images
« Last post by golunvolo on March 24, 2023, 22:57:23 »
First image I shot today.
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