A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » Digital Photography » Digital Photography
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Funky IR Artefact



 
 
Thread Tools Display Modes
  #21  
Old April 27th 18, 12:23 AM posted to rec.photo.digital
Eric Stevens
external usenet poster
 
Posts: 13,611
Default Funky IR Artefact

On Thu, 26 Apr 2018 02:05:37 -0700 (PDT), Whisky-dave
wrote:

On Thursday, 26 April 2018 04:28:03 UTC+1, Eric Stevens wrote:
On Wed, 25 Apr 2018 05:32:11 -0700 (PDT), Whisky-dave
wrote:

On Wednesday, 25 April 2018 13:07:56 UTC+1, android wrote:
On 2018-04-25 11:31:01 +0000, Whisky-dave said:

How can you take an IR photograph while yuor camera has an IR filter to
cut out IR from getting to the sensor.

Do some thinking...

come on then tell me how IR gets through the lens to the camera sensor and through the IR filter that is on the sensor so it doesn't reposnd to IR 'light'

All he has to do is travel towards the subject at a speed sufficiently
high to shift the IR into the visible part of the spectrum.


He'll get that wrong too, he'll travel so fast it'll get into the UV specrum and he;'ll annoucnce that the universe has disapeared because he canlt see it.


He will need to use a high shutter speed.


That's the least of his problems.

Not unless he wants to take the image before he crashes into the
subject.
--

Regards,

Eric Stevens
  #22  
Old April 27th 18, 03:11 AM posted to rec.photo.digital
PeterN[_7_]
external usenet poster
 
Posts: 1,161
Default Funky IR Artefact

On 4/24/2018 12:16 PM, android wrote:
On 2018-04-23 17:29:56 +0000, PeterN said:

On 4/23/2018 1:34 AM, android wrote:
On 2018-04-22 18:53:51 +0000, RichA said:

On Sunday, 22 April 2018 05:40:30 UTC-4, androidÂ* wrote:
Trée arty but... WTF is it???

https://dl.dropboxusercontent.com/s/mjfnh2d0s1wulli/i180422%2311638.jpg


For the record: I used a IR filter on a unconverted EOS M with high
ISO settings. Hard to work without an OVF, witch I have...
--
teleportation kills

I tend to use a Leica viewfinder in the hotshoe, a wide angle lens
set to f/8 so proximity focus is easy.Â* A mild IR filter (cutoff,
around 800nm on a camera with its IR filter removed can easily be
handheld in daylight or even overcast, but a deep IR cutoff
(1000+nm) means using a tripod.Â* A camera with the IR sensor filter
in-place is a pain, cutting out so much of the IR than any exposures
with an IR filter over the lens means seconds of time.

I've got a 760nm totally black filter, so there is an overlapping gap
between the high end of the visible spectrum and low end of the IR
one and that can be used at high ISOs sunny days. If you got steady
hands, there is another example from a few years ago in the gallery
on my blog.

https://wp.me/P3strj-7Y

I've gotten it down to where I can convert an old Nikon D70 (the
easiest camera to convert) in 15 minutes.

I might just pull the the filter stack out of the EOS M eventually.
Can't be that difficult...


You might lose autofocuse. The near IR light has a different wavelength.


On a mirrorless? Don't think soo...


You may be right. I had the IR filter pulled on my P&S, and did not lose
autofocus. It may depend on the size of your sensor. According to
articles I've read, you lose AF if you try that on a full frame.

--
PeterN
  #23  
Old April 27th 18, 03:15 AM posted to rec.photo.digital
PeterN[_7_]
external usenet poster
 
Posts: 1,161
Default Funky IR Artefact

On 4/24/2018 12:16 PM, android wrote:
On 2018-04-23 17:25:54 +0000, PeterN said:

On 4/22/2018 5:40 AM, android wrote:
Trée arty but... WTF is it???

https://dl.dropboxusercontent.com/s/mjfnh2d0s1wulli/i180422%2311638.jpg


For the record: I used a IR filter on a unconverted EOS M with high
ISO settings. Hard to work without an OVF, witch I have...


Did a quick and dirty post, (surface blur and increased fog a bit,)
just to get rid of most of the artifacts.

https://www.dropbox.com/s/97ubvg4wj71xn2d/i180422%2311638.jpg?dl=0


I did a q n d myself in a follow up to the OP. The file is broken so I
did not take it any further... The white streak to the left is that what
puzzles me. Do you know what it is?


if you're talking about the curved line, I think it's the edge of a
curtain, that is OOF.

--
PeterN
  #24  
Old April 27th 18, 03:53 AM posted to rec.photo.digital
android
external usenet poster
 
Posts: 3,854
Default Funky IR Artefact

On 2018-04-27 02:11:45 +0000, PeterN said:

On 4/24/2018 12:16 PM, android wrote:
On 2018-04-23 17:29:56 +0000, PeterN said:

On 4/23/2018 1:34 AM, android wrote:
On 2018-04-22 18:53:51 +0000, RichA said:

On Sunday, 22 April 2018 05:40:30 UTC-4, android* wrote:
Trée arty but... WTF is it???

https://dl.dropboxusercontent.com/s/mjfnh2d0s1wulli/i180422%2311638.jpg

For the record: I used a IR filter on a unconverted EOS M with high
ISO settings. Hard to work without an OVF, witch I have...
--
teleportation kills

I tend to use a Leica viewfinder in the hotshoe, a wide angle lens set
to f/8 so proximity focus is easy.* A mild IR filter (cutoff, around
800nm on a camera with its IR filter removed can easily be handheld in
daylight or even overcast, but a deep IR cutoff (1000+nm) means using a
tripod.* A camera with the IR sensor filter in-place is a pain, cutting
out so much of the IR than any exposures with an IR filter over the
lens means seconds of time.

I've got a 760nm totally black filter, so there is an overlapping gap
between the high end of the visible spectrum and low end of the IR one
and that can be used at high ISOs sunny days. If you got steady hands,
there is another example from a few years ago in the gallery on my blog.

https://wp.me/P3strj-7Y

I've gotten it down to where I can convert an old Nikon D70 (the
easiest camera to convert) in 15 minutes.

I might just pull the the filter stack out of the EOS M eventually.
Can't be that difficult...

You might lose autofocuse. The near IR light has a different wavelength.


On a mirrorless? Don't think soo...


You may be right. I had the IR filter pulled on my P&S, and did not
lose autofocus. It may depend on the size of your sensor. According to
articles I've read, you lose AF if you try that on a full frame.


We are talking mirrorless here...
--
teleportation kills

  #25  
Old April 27th 18, 03:53 AM posted to rec.photo.digital
android
external usenet poster
 
Posts: 3,854
Default Funky IR Artefact

On 2018-04-27 02:15:34 +0000, PeterN said:

On 4/24/2018 12:16 PM, android wrote:
On 2018-04-23 17:25:54 +0000, PeterN said:

On 4/22/2018 5:40 AM, android wrote:
Trée arty but... WTF is it???

https://dl.dropboxusercontent.com/s/mjfnh2d0s1wulli/i180422%2311638.jpg

For the record: I used a IR filter on a unconverted EOS M with high ISO
settings. Hard to work without an OVF, witch I have...

Did a quick and dirty post, (surface blur and increased fog a bit,)
just to get rid of most of the artifacts.

https://www.dropbox.com/s/97ubvg4wj71xn2d/i180422%2311638.jpg?dl=0


I did a q n d myself in a follow up to the OP. The file is broken so I
did not take it any further... The white streak to the left is that
what puzzles me. Do you know what it is?


if you're talking about the curved line, I think it's the edge of a
curtain, that is OOF.


No. I have files taken att the same time and it's not there. Probably a
hot spot with floded photon wells with the surplus photons following
gravity...
--
teleportation kills

  #26  
Old April 27th 18, 11:37 AM posted to rec.photo.digital
android
external usenet poster
 
Posts: 3,854
Default Funky IR Artefact

On 2018-04-27 10:24:51 +0000, Whisky-dave, AKA Dense Dave said:

Well that certainly is funny, are you sure it's not microscopic aliens


No, it's photonics lemmings...
--
teleportation kills

  #27  
Old April 27th 18, 12:54 PM posted to rec.photo.digital
nospam
external usenet poster
 
Posts: 24,165
Default Funky IR Artefact

In article ,
Whisky-dave wrote:

Focusing with a mirrorless

Cameras don't use the mirrors to focus the image,


slrs have a secondary mirror behind the main mirror for the autofocus
system to work, which has its own sensor.

mirrorless focus using the main sensor.


Really, when I focus my M3 I use the focusing ring on the lens for manual focus.


whooooooosh.
  #28  
Old April 27th 18, 02:38 PM posted to rec.photo.digital
nospam
external usenet poster
 
Posts: 24,165
Default Funky IR Artefact

In article ,
Whisky-dave wrote:

Focusing with a mirrorless

Cameras don't use the mirrors to focus the image,

slrs have a secondary mirror behind the main mirror for the autofocus
system to work, which has its own sensor.

mirrorless focus using the main sensor.

Really, when I focus my M3 I use the focusing ring on the lens for manual
focus.


whooooooosh.


Gone right over yuor head hasn;t it, why do they but IR markings on lenes and
this gose back well before mirrorless are yuo really climing that IR light
focussess differntly for mirrorless cameras ?


whoooooosh even higher.

plus, modern lenses don't have ir markers anymore.
  #29  
Old April 27th 18, 03:23 PM posted to rec.photo.digital
Savageduck[_3_]
external usenet poster
 
Posts: 16,487
Default Funky IR Artefact

On Apr 27, 2018, Whisky-dave wrote
(in ):


Gone right over yuor head hasn;t it, why do they but IR markings on lenes and
this gose back well before mirrorless are yuo really climing that IR light
focussess differntly for mirrorless cameras ?


Yes.

Mirrorless cameras have the ability to AF IR light without focusing issues
found in DSLRs. Typically with IR converted DSLRs camera/lens combos have to
be calibrated, not so with mirrorless.

With mirrorless cameras AF happens via the sensor, and you get a realtime
preview of the image before capture in either the EVF and on LCD.

Here is one photographer's experience.

https://neilvn.com/tangents/mirrorless-cameras-and-bw-infrared-photography/

--

Regards,
Savageduck

  #30  
Old April 27th 18, 03:42 PM posted to rec.photo.digital
nospam
external usenet poster
 
Posts: 24,165
Default Funky IR Artefact

In article ,
Whisky-dave wrote:

Focusing with a mirrorless

Cameras don't use the mirrors to focus the image,

slrs have a secondary mirror behind the main mirror for the
autofocus system to work, which has its own sensor.

mirrorless focus using the main sensor.

Really, when I focus my M3 I use the focusing ring on the lens for
manual focus.

whooooooosh.

Gone right over yuor head hasn;t it, why do they but IR markings on lenes
and this gose back well before mirrorless are yuo really climing that IR
light focussess differntly for mirrorless cameras ?


whoooooosh even higher.

plus, modern lenses don't have ir markers anymore.


So WTF has that got to do with it.
IR works in the same way it has done since the big bang
whether or not lenes have a mark on them is irrelivant.


what you fail to understand is that a mirrorless camera focuses off the
actual sensor, while slr has a *separate* focus module.

in other words, with mirrorless, what you see is what you get. lens
markings do not matter. different wavelengths do not matter. if it's in
focus in the viewfinder or on the rear display, it will be in focus on
the actual photo. always.

with an slr, the focus module is separate, using a secondary mirror
behind the main mirror to reflect light to the focus sensor module. it
is calibrated for visible light, so for infrared, either you adjust for
the difference (using lens markings) or the focus system needs to be
recalibrated for infrared.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Nikon Coolpix L3 funky snapshot delay John Doe Digital Photography 1 January 8th 09 08:20 PM
Tested lens, got funky stripes in sky... baker1 Digital Photography 11 February 5th 06 06:54 AM
FS Olympus digital camera, printer NIB plus funky old rangefinders! Isaac Crawford Digital Photo Equipment For Sale 0 October 17th 04 06:53 AM


All times are GMT +1. The time now is 10:38 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PhotoBanter.com.
The comments are property of their posters.