Barreling?
George
A close-up (-ish, say 1 to 2metres) has curved horizontal lines that should
be straight.
They curve slightly away from the centre line.
(Is this barrelling, or pin-cushion?)
In CS, is there anything I can do to straighten things?
Any comments appreciated,
george
who remembers "PRESS PLAY ON TAPE #1"
John Stafford
"George" <georg...@btinternet.com> wrote:
> Hi!
> A close-up (-ish, say 1 to 2metres) has curved horizontal lines that should
> be straight.
> They curve slightly away from the centre line.
> (Is this barrelling, or pin-cushion?)
> In CS, is there anything I can do to straighten things?
Here is a good start, George:
Such distortion is quite common to zoom lenses and cheap wide-angle
lenses. Wide lenses without such distortion are, for the most part,
terribly expensive.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.ten> found these unused words:
>
> >Such distortion is quite common to zoom lenses and cheap wide-angle
> >lenses. Wide lenses without such distortion are, for the most part,
> >terribly expensive.
>
> "For the most part" ???
Yup. I'm still dreaming of an inexpensive very-wide lens of excellent
quality.
> Are there -=any=- wide angle lenses that are 'flat field'?
Probably not.
> AFAIK, it's a function of optics until you reach about 60 mm [35mm
> equivalent].
Some lens designs produce less distortion than others of the same focal
length. Look to the later Biogon design for some remarkable correction
of distortion. In particular, look at the Biogon 38mm as used in the
Hasselblad SWC, 903, 905 (58mm x 58mm format)
Design is all about trade-offs. The Biogon does not have great coverage
for its FL, and it's coverage does not increase with stopping down.
OTOH, the 35mm Grandagon has great coverage, but with great light
fall-off to the edges which is improved by stapping down. The Biogon has
remarkable sharpness wide-open while the Grandagon has terrible
performance at the same aperture.
And each are terribly expensive.
JD
> John Stafford<nh...@droffats.ten> found these unused words:
>
>> lenses. Wide lenses without such distortion are, for the most part,
>> terribly expensive.
>
>
>
> equivalent].
>
When I used film and shot interiors and exteriors, I had a Nikon 20mm
lens that had no distortion. ff you put the film plane parallel to the
building or interior, everything on the very edge of the shot was
square, straight up and down, top and bottom. It was a very nice lens!
They still make it:
AF NIKKOR 20mm f/2.8D
"Close Range Correction for distortion-free pictures as close as 0.85 feet."
$564.95 at Amazon.
I've retired and now shoot what my photo colleagues call a "pro-sumer"
35mm DSLR camera. It's got a little distortion on the wide angle shots.
The body and two lenses cost less than the above lens. ;-)
And to get the full 20mm lens coverage, you'd need a full frame digital
sensor which means you need a Nikon D3, for about $5,000, a D3S or D3X,
for about$7,500.
--
JD..
JD
CS3 has something that may help. Filter, Distort, Lens Correction.
I don't know what it's called, just how to lessen it! If it curves out,
I think it's called barrel distortion(caused by a wide angle lens), if
it curves in I think it's call pin-cushion distortion(caused by a long
telephoto lens) but don't get me to lying.
When in doubt, Ask.com:
http://en.wikipedia.org/wiki/Distortion_(optics)
--
JD..
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.ten> found these unused words:
> >Design is all about trade-offs. The Biogon does not have great coverage
> >for its FL, and it's coverage does not increase with stopping down.
> >OTOH, the 35mm Grandagon has great coverage, but with great light
> >fall-off to the edges which is improved by stapping down. The Biogon has
> >remarkable sharpness wide-open while the Grandagon has terrible
> >performance at the same aperture.
> >
> >And each are terribly expensive.
>
> True, a friend has the Biogon [deals with medical imagery - so aptly named
> <G>].
If it is used for close-up photography, then it is being applied outside
of its design goals, and I would expect significant issues.
> Even so, shootng a grid card shows distortion.
The closer the grid is focused upon, the more significant the distortion
- and the longer the focal length, which defeats its design objective.
Regardless, .5% is very good for a wide lens.
> Thankfully, digitally post we can 'adjust' for it.
Usually don't have to.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.ten> found these unused words:
>
> >In article <k73fj51mas6oshaqk...@4ax.com>,
> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >
> >> John Stafford <nh...@droffats.ten> found these unused words:
> >
> >> >Design is all about trade-offs. The Biogon does not have great coverage
> >> >for its FL, and it's coverage does not increase with stopping down.
> >> >OTOH, the 35mm Grandagon has great coverage, but with great light
> >> >fall-off to the edges which is improved by stapping down. The Biogon has
> >> >remarkable sharpness wide-open while the Grandagon has terrible
> >> >performance at the same aperture.
> >> >
> >> >And each are terribly expensive.
> >>
> >> True, a friend has the Biogon [deals with medical imagery - so aptly named
> >> <G>].
> >
> >If it is used for close-up photography, then it is being applied outside
> >of its design goals, and I would expect significant issues.
>
> Didn't make that statement! It's used at normal distances, but where ther's
> insufficient space for him to cover the field needed.
OK! We are good there. It is good to exchange information with a person
like you who knows the field.
Thanks.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> I've always used either a bellows of tubes for my close work, usually with a
> reversing ring on my 58 1.4 Nikkor on the original "F". Lovely control of
> depth of field that way too <G>!
>
> Happy New Year.
Happy New Year to you, and all.
I'll have to put up some pictures of the Nikon F hack I made. Maybe.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.net> found these unused words:
> Speaking of hacks, something you might find amusing:
> lephoto.ttrr.org/interval/interval.html
It certainly beats leaving a laptop outside to use as an intervalometer!
Digital is boring me, but I gotta do it for the day job.
John Stafford
> It's 'digital' in the sense that the main components are integrated
> circuits. However it can be used for any camra system, with additional
> battery it would drive a solenoid for a cable release, or if the camera has
> a dry circuit remote, that connection.
How would it replace the dark slide, remove the film holder, flip it
over, pull the slide and cock the shutter for the next shot?
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.net> found these unused words:
>
> >In article <oamkj5tgj8e1ag1ov...@4ax.com>,
> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >
> >> John Stafford <nh...@droffats.net> found these unused words:
> >>
> >> >In article <dj9kj5lb3q5ac80ab...@4ax.com>,
> >> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >
> >> >> Speaking of hacks, something you might find amusing:
> >> >> lephoto.ttrr.org/interval/interval.html
> >> >
> >> >It certainly beats leaving a laptop outside to use as an intervalometer!
> >> >
> >> >Digital is boring me, but I gotta do it for the day job.
> >>
> >> It's 'digital' in the sense that the main components are integrated
> >> circuits. However it can be used for any camera system, with additional
> >> battery it would drive a solenoid for a cable release, or if the camera has
> >> a dry circuit remote, that connection.
> >
> >How would it replace the dark slide, remove the film holder, flip it
> >over, pull the slide and cock the shutter for the next shot?
>
> Speed Graphic ?
Deardorff 8x10
> Rotary solenoid to use with the 6 pack, but the cocking would be ??? Too
> bulky anyway, but interesting concept.
>
> What's the slowest exposure you've made successfully with it? Managed one at
> 1/8th, though it took 3 tries. Eglise Saint-Sulpice concert, NO FLASH
> ALLOWED!
Slowest hand-held? I can't hand hold this monster. Besides, I got a
tremor.
I have a lot of infrared flash bulbs. Would have to go down to 4x5",
tho. They wouldn't know I was there. 'cept if someone in front of me's
hair burst into flames. Ever since I shot a Michael Jackson rehearsal...
> Many other cameras have motorized backs. Expose, wind, expose, wind.
> There'll always be something you -=can't=- use it with <G>!
I have used 9" rollfilm, but that was a big-ass military aerial thang.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.net> found these unused words:
>
> >In article <g4qkj5dhi4om1242d...@4ax.com>,
> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >
> >> John Stafford <nh...@droffats.net> found these unused words:
> >>
> >> >In article <oamkj5tgj8e1ag1ov...@4ax.com>,
> >> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >> >
> >> >> John Stafford <nh...@droffats.net> found these unused words:
> >> >>
> >> >> >In article <dj9kj5lb3q5ac80ab...@4ax.com>,
> >> >> > Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> >> >
> >> >> >> Speaking of hacks, something you might find amusing:
> >> >> >> lephoto.ttrr.org/interval/interval.html
> >> >> >
> >> >> >It certainly beats leaving a laptop outside to use as an
> >> >> >intervalometer!
> >> >> >
> >> >> >Digital is boring me, but I gotta do it for the day job.
> >> >>
> >> >> It's 'digital' in the sense that the main components are integrated
> >> >> circuits. However it can be used for any camera system, with additional
> >> >> battery it would drive a solenoid for a cable release, or if the camera
> >> >> has
> >> >> a dry circuit remote, that connection.
> >> >
> >> >How would it replace the dark slide, remove the film holder, flip it
> >> >over, pull the slide and cock the shutter for the next shot?
> >>
> >> Speed Graphic ?
> >
> >Deardorff 8x10
>
> Lovely, only got to use one once! Personal property of the Sergeant-Major.
>
> >> Rotary solenoid to use with the 6 pack, but the cocking would be ??? Too
> >> bulky anyway, but interesting concept.
> >>
> >> What's the slowest exposure you've made successfully with it? Managed one
> >> at
> >> 1/8th, though it took 3 tries. Eglise Saint-Sulpice concert, NO FLASH
> >> ALLOWED!
> >
> >Slowest hand-held? I can't hand hold this monster. Besides, I got a
> >tremor.
>
> Ahhh, but that was 'back when' for me [47 years ago!].
>
> >I have a lot of infrared flash bulbs. Would have to go down to 4x5",
> >tho. They wouldn't know I was there. 'cept if someone in front of me's
> >hair burst into flames. Ever since I shot a Michael Jackson rehearsal...
>
> Not going there ...
>
> >> Many other cameras have motorized backs. Expose, wind, expose, wind.
> >> There'll always be something you -=can't=- use it with <G>!
> >
> >I have used 9" rollfilm, but that was a big-ass military aerial thang.
>
> Would do a nice job on shooting for the Pani Projectors ...
> http://www.pani.com/produkte/projektion/e_projektion.html?english
>
> Used them to 'light-up' Vegas casino towers. Caesar's for Cinquo de Mayo -
> Bally's [Old MGM] for Chevy Introduction of the Geo - as examples.
>
> Now it's all PS and Video ... the -=fun=- is gone.
47 years for you. Wow! You are a contemporary. I'm 63 years-old now, and
a tiny bit of my aerial experience was Vietnam 64-70. OMG, this is kind
of depressing.
Best to you, Sir.
George
We have wandered a bit!
Sorry for the extended messages.
It's CS here, not CS3.
But, the pinch and spherics things may help a bit.
Thanks for the info.
will try it now.
George
"JD" <J...@example.invalid> wrote in message
news:3pGdndFcqKm796vW...@posted.grandecom...
David Smith
>>> How would it replace the dark slide, remove the film holder, flip it
>>> over, pull the slide and cock the shutter for the next shot?
>> Speed Graphic ?
Someone, in the late 80's - early 90's was actually marketing a "motor
drive" fr 4x5 sheet film.
As I recall, it had a chamber on the top which held 50 sheets of film, a
roller transport to move the sheets into position and a chamber on the
bottom to receive the exposed film.
I remember seeing it demoed at Photo Expo in NY. It was being geared
toward fashion shooters.
Dave Smith
John Stafford
David Smith <dcsimag...@yahoo.com> wrote:
The justification probably being that nobody made the desirable color
rollfilm in 5"x180' format.
Wish I had seen it.
Mike Russell
John Stafford
Mike Russell <grou...@MOVEcurvemeister.com> wrote:
If you had X-Rays on the before they went digital, you might have heard
the clunk of the film changer. Rather bulky, but I'll bet it is similar
to the device shown at Photo Expo.
David Smith
Actually it sounded like a deck of cards being shuffled as I recall.
I was there with a friend who was a big still life shooter at the time
and we were quizzing the guy doing the demo.
One of the things we brought up was static electricity and the the
answer was "We recommend keeping the humidity in the studio rather high".
Dave Smith
george
> Hi!
> A close-up (-ish, say 1 to 2metres) has curved horizontal lines that
> should be straight.
> They curve slightly away from the centre line.
> (Is this barrelling, or pin-cushion?)
> In CS, is there anything I can do to straighten things?
>
> Any comments appreciated,
> george
> who remembers "PRESS PLAY ON TAPE #1"
>
Found it in Elements.
Filter>correct camera distortion
So, why buy an expensive lens!
george
John Stafford
george <georg...@btinternet.com> wrote:
> Found it in Elements.
> Filter>correct camera distortion
>
> So, why buy an expensive lens!
Uh, to avoid the reliance upon the software? To get it right the first
time? To avoid degradation of the image through manipulation?
JD
If you shoot interiors and exteriors for a living, you have the lens. If
you shoot for yourself, software is a less expensive alternative.
--
JD..
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.net> found these unused words:
>
> To avoid fall off of both light and focus at the corners.
Light fall-off to the edges is hard to defeat, although the later Biogon
design does a pretty good job. Focus - yes, for sure, quality lenses are
a must for that.
Michael J Davis
>George wrote:
>> Hi!
>> A close-up (-ish, say 1 to 2metres) has curved horizontal lines that
>> should be straight.
>> They curve slightly away from the centre line.
>> (Is this barrelling, or pin-cushion?)
>> In CS, is there anything I can do to straighten things?
>>
>> Any comments appreciated,
>> george
>> who remembers "PRESS PLAY ON TAPE #1"
>>
>
>
>I don't know what it's called, just how to lessen it! If it curves out,
>I think it's called barrel distortion(caused by a wide angle lens), if
>it curves in I think it's call pin-cushion distortion(caused by a long
>telephoto lens) but don't get me to lying.
>
>When in doubt, Ask.com:
>
>http://en.wikipedia.org/wiki/Distortion_(optics)
The trouble with the youngsters today is that they've never seen a
simple pincushion!!
Think of two squares of fabric sewn together at the edges and tightly
filled with stuffing. The edges curve in but the corners stick out!
After searching the web for a picture the best I can do is.
http://www.flickr.com/photos/someartfabricphoto/4047538406/
... which isn't stuffed quite tightly enough. ;-)
Mike
--
Michael J Davis
<Photographing the public for over fifty years>
JD
I don't know about "youngsters today" but you replied to my post so I'll
have to admit that I do know what a pincushion is. 8-)
--
JD..
John Stafford
JD <J...@example.invalid> wrote:
> Michael J Davis wrote:
> > The trouble with the youngsters today is that they've never seen a
> > simple pincushion!!
> >
> > Think of two squares of fabric sewn together at the edges and tightly
> > filled with stuffing. The edges curve in but the corners stick out!
> >
> > After searching the web for a picture the best I can do is.
> >
> > http://www.flickr.com/photos/someartfabricphoto/4047538406/
> >
> > ... which isn't stuffed quite tightly enough. ;-)
> >
> > Mike
>
> I don't know about "youngsters today" but you replied to my post so I'll
> have to admit that I do know what a pincushion is. 8-)
I remember when we did not use batteries to fire flash bulbs. In fact, I
still do that.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> John Stafford <nh...@droffats.net> found these unused words:
> >I remember when we did not use batteries to fire flash bulbs. In fact, I
> >still do that.
>
> Other than flash powder and a match, AFAIK, the bulb type 'flash' holders
> had either a D or a C cell. Something had to supply a small electric 'zap'
> for the bulb to ignite. Just shorting the bulb contacts did not do it!
Ah hah! My friend, Sir Rien! Permit me to contribute.
After WWII, at least two companies came out with flash units for
existing flash bulbs so that the flash unit required no batteries.
The English company did the same, but not do well.
In the USA, a company made the FlashTronic models (interesting in that
they got into this mixed captial-one-word thing in the fifties).
I have one of each model of the FlashTronic and two of one model.
How did they flash a bulb without batteries? (No, they did not wait for
lightning). The flash as a small magneto in the base. Like most big bulb
flashes of the time, one would press a button on the flash that started
the bulb and 20 milliseconds later triggered the leaf flash.
Want pictures of the things?
* Much later in the Sixties Kodak came out with Flash Cubes that
required no battery for their little Instamatic. But those were toys
compared to real flash bulbs which are a million or more times brighter.
JD
I have some questions for you:
Didn't the Kodak flash cubes use the batteries in the camera to fire?
I took a class in college, East Texas State University, class of 1975,
that was taught by Joe Costa who was one of the early pioneers of flash
photography. He took a picture of an aircraft carrier with a plane
taking off at night illuminated by flash bulbs. I've never been able to
find a copy of that photograph online. Are you familiar with that shot?
How old are you? I'm 57, in case you're curious.
--
JD..
John Stafford
JD <J...@example.invalid> wrote:
> Didn't the Kodak flash cubes use the batteries in the camera to fire?
Perhaps. There was also the Magicube (spelling) (too lazy to look it
up). One or the other used a bit of pyrotechnics to ignite by percussion.
> I took a class in college, East Texas State University, class of 1975,
> that was taught by Joe Costa who was one of the early pioneers of flash
> photography. He took a picture of an aircraft carrier with a plane
> taking off at night illuminated by flash bulbs. I've never been able to
> find a copy of that photograph online. Are you familiar with that shot?
I might recognize the photo. Joe was famous to me when I was younger,
and a member of the NPPPA.
> How old are you? I'm 57, in case you're curious.
I am sixty-four years-old.
John Stafford
Sir F. A. Rien <jaS...@gbr.online.com> wrote:
> You all might then enjoy the images of the Norfolk & Western shot by O.
> Winston Link - can we do that digitally?
I truly know O. Winston Link's work. I still shoot flashbulbs, but I am
now down to four cases of Edison base flashes. Can you do it digitally?
No. Light is light. You cannot create light with digital, even with
massive ISO ratings because they just go into noise which reduces the
effective pixel count for quality.
Michael J Davis
>I'll have to admit that I do know what a pincushion is. 8-)
:-)
I wasn't referring to you, but I have met a number of people who don't
know what a pincushion is!!
Mike
--
Michael J Davis
<><
"I never have taken a picture I've intended.
They're always better or worse."
Diane Arbus
<><
Michael J Davis
>Michael J Davis <mjdu...@trustsof.co.uk> found these unused words:
>>
>>I wasn't referring to you, but I have met a number of people who don't
>>know what a pincushion is!!
>
LOL!
But there's always a needle for it! ;-)
Mike
--
Michael J Davis
<><
Another day over. Objectives fulfilled. Deadlines met.
Pigs fed and ready for take off.
<><