Go Back   Team-BHP > Around the Corner > Shifting gears > Gadgets, Computers & Software


Reply
 
Thread Tools Search this Thread
Old 24th May 2011, 21:43   #7591
BHPian
 
Join Date: Oct 2005
Location: chennai
Posts: 756
Thanked: 295 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by amolpol View Post
I dont have a light meter so I use a very popular technique to do this - guesstimate. Sometimes it needs more than 2 tries to get acceptable results.
Hope you read my comment about usage of a separate light meter.



Quote:
Originally Posted by Aroy View Post

The camera's light meter always works the same, it is its interpretation that differs from a human. The meter calculates the exposure by assuming that the world is Grey. This holds for most of the cases, but there are exceptions. Those are when the contrast is very high, or the case of a black cat on snow. In such case you have to deviate from what the camera tells you. Details are available on the net.
You are absolutely right, but my point right from the beginning was that Camera meter works the same way irrespective of whether it Av/Tv or M mode. If the meter gives you incorrect reading, it will be consistently incorrect across all the above modes.
tifosikrishna is offline   Reply With Quote
Old 24th May 2011, 23:31   #7592
BHPian
 
Join Date: Nov 2009
Location: Bangalore
Posts: 604
Thanked: 186 Times
Default Re: The DSLR Thread

The new Nikkor 50mm f/1.8G's bokeh seems to be better than the 1.8D's!!
Lens to be released on June 2.
https://picasaweb.google.com/Witkovs...00AFS50mmF18G#
WindRide is offline   Reply With Quote
Old 25th May 2011, 00:44   #7593
Senior - BHPian
 
nitrous's Avatar
 
Join Date: May 2004
Location: UAE/Lon/Madras
Posts: 6,966
Thanked: 282 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by WindRide View Post
The new Nikkor 50mm f/1.8G's bokeh seems to be better than the 1.8D's!!
Lens to be released on June 2.
https://picasaweb.google.com/Witkovs...00AFS50mmF18G#
What's the price of this G gonna be?
I'm looking to get a prime.
nitrous is offline   Reply With Quote
Old 25th May 2011, 01:20   #7594
BHPian
 
Join Date: Nov 2009
Location: Bangalore
Posts: 604
Thanked: 186 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by nitrous View Post
What's the price of this G gonna be?
...
$219 ONLY!!!
WindRide is offline   Reply With Quote
Old 25th May 2011, 02:10   #7595
Newbie
 
Join Date: Mar 2010
Location: Sydney
Posts: 5
Thanked: 5 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by lucifer1881 View Post
It is not a film vs. digital issue. Old school photographers use M mode because in the olden days the cameras either did not have in-built meters or the in-built meters did not work well. They had to use dedicated meters and then manually set those values in their cameras. Use of M mode today is a hangover of those days.
Quote:
Originally Posted by lucifer1881 View Post
I was not referring to professional photo shoots with multiple lights or reflectors. Yes, there are instances when M mode is the only way to go. But those instances are few and far between. The thing is M mode is used more often than it is needed. And that is a hangover from the olden days.
Sorry mate, but M mode is not a hangover, I didn't shoot when it was film era, I only entered the realm of photography when it had already gone digital. Yes i shoot film but that is more for fun than anything.

I used to use Av almost exclusively but then I had less than 50% keepers, more than 50% of my shots were, well rubbish. Then I went M exclusively and those issues with those 50% shots started to go away, I was taking time adjusting settings and composition, at first it was hard but after few weeks it became second nature, now I can look at lighting at and event/indoors/outdoors and spit-out a setting that would work (not 100% perfect but it would work).

Just to be clear 90% of my images don't need any PP, 10% are location shots which need proper PP. Despite have properly exposed images, my camera meter always tells me I am shooting more than 2stops underexposed, go figure that out.
rajb3125 is offline   Reply With Quote
Old 25th May 2011, 08:25   #7596
Senior - BHPian
 
R2D2's Avatar
 
Join Date: Oct 2008
Location: Punya Nagari
Posts: 1,733
Thanked: 877 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by nitrous View Post
What's the price of this G gonna be?
I'm looking to get a prime.
Quote:
Originally Posted by WindRide View Post
$219 ONLY!!!
It's INR 13,450 MRP and GBP 199.95 @ Jessops (for Nitrous in Birmingham).

INR street price will be slightly less say between 12.5 to 13K. When seen on its own, this lens may seem like good VFM on the price v/s performance factor. But it is ~2x the price of the old model hence that VFM factor drops considerably.

Regards,
R2D2 is offline   Reply With Quote
Old 25th May 2011, 09:14   #7597
Team-BHP Support
 
tsk1979's Avatar
 
Join Date: Feb 2005
Location: New Delhi
Posts: 22,882
Thanked: 15,535 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by rajb3125 View Post
Despite have properly exposed images, my camera meter always tells me I am shooting more than 2stops underexposed, go figure that out.
You should buy a good modern camera with automatic metering.
As a professional, equipment is very important.
tsk1979 is offline   Reply With Quote
Old 25th May 2011, 09:49   #7598
Senior - BHPian
 
Join Date: Aug 2010
Location: Delhi
Posts: 2,105
Thanked: 983 Times
Default Re: The DSLR Thread

Most of us use the averaging meter. Very few use the spot meter function. In a scene where there is a lot of contrast (dynamic range), you have to decide which part you want perfectly exposed and which are auxiliary, and then you use the metering point at that spot. Just like using AF spots to focus off centre.

Manual settings let us choose what we know/think is the best, without wasting time selecting spots where to meter. At times this also works for focusing. You focus on what you want and not what the camera thinks you want.

All said and done, if you are good in selecting exposure, them manual is faster and better, else if you are not, relying on the camera is a better bet.
Aroy is offline   Reply With Quote
Old 25th May 2011, 10:15   #7599
Senior - BHPian
 
Join Date: Dec 2010
Location: Ghaziabad/Hyderabad/Mysore
Posts: 1,416
Thanked: 313 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by Aroy View Post
Most of us use the averaging meter. Very few use the spot meter function. In a scene where there is a lot of contrast (dynamic range), you have to decide which part you want perfectly exposed and which are auxiliary, and then you use the metering point at that spot. Just like using AF spots to focus off centre.

Manual settings let us choose what we know/think is the best, without wasting time selecting spots where to meter. At times this also works for focusing. You focus on what you want and not what the camera thinks you want.

All said and done, if you are good in selecting exposure, them manual is faster and better, else if you are not, relying on the camera is a better bet.

As @tsk wrote earlier, wouldn't bracketing more or less take care of this issue? You'll have multiple shots in quick succession with different exposures and you can chose to delete some


By the way, do you have any idea what kind of dynamic range do you get out of top-of-the-line DSLRs and mid-range DSLRs these days?

cheap camera sensors can not do more than 8bits (i.e. about 1 in 200)
vina is offline   Reply With Quote
Old 25th May 2011, 10:18   #7600
BHPian
 
bikxsans660's Avatar
 
Join Date: Mar 2011
Location: Mumbai
Posts: 43
Thanked: 9 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by WindRide View Post
The new Nikkor 50mm f/1.8G's bokeh seems to be better than the 1.8D's!!
Lens to be released on June 2.
https://picasaweb.google.com/Witkovs...00AFS50mmF18G#
Any idea about the cost at launch? Am planning to switch over from my 1.8D to the newer model.
bikxsans660 is offline   Reply With Quote
Old 25th May 2011, 10:18   #7601
Team-BHP Support
 
Samurai's Avatar
 
Join Date: Jan 2005
Location: B'lore-Manipal
Posts: 22,141
Thanked: 13,720 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by Aroy View Post
Most of us use the averaging meter. Very few use the spot meter function.
Well, you can blame that on Canon, for not giving spot metering on their entry level dSLRs. Five years back when I shopped for my first dSLR, I rejected Canon for that reason.

Quote:
Originally Posted by Aroy View Post
Manual settings let us choose what we know/think is the best, without wasting time selecting spots where to meter. At times this also works for focusing. You focus on what you want and not what the camera thinks you want.

All said and done, if you are good in selecting exposure, them manual is faster and better, else if you are not, relying on the camera is a better bet.
Hmm, you mean you trust your eyes more than the TTL meter for measuring the exposure? Surprising. I have often seen Rudra patiently using multi-spot metering. I used to think it was overkill, but he used to say it was necessary to get it right. My camera has only single-spot metering, I am fine with that.
Samurai is offline   Reply With Quote
Old 25th May 2011, 10:42   #7602
Senior - BHPian
 
Join Date: Aug 2010
Location: Delhi
Posts: 2,105
Thanked: 983 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by vina View Post
As @tsk wrote earlier, wouldn't bracketing more or less take care of this issue? You'll have multiple shots in quick succession with different exposures and you can chose to delete some


By the way, do you have any idea what kind of dynamic range do you get out of top-of-the-line DSLRs and mid-range DSLRs these days?

cheap camera sensors can not do more than 8bits (i.e. about 1 in 200)
Yes bracketing would do, but then it is difficult to get same view when action is fast (or when there is any action). Bracketing was in fashion with film cameras as you never knew if the shots were perfectly exposed, especially with slide film. With DSLR you can always view the Histogram and correct your exposure.

Dynamic Range varies
- MFDB : 10-13 stops
- DSLR high end : 9-12 stops
- DSLR medium end : 8-11 stops
- Small Sensors : 8-10 stops
The major problem is that if you do not use RAW (or do not have that option), you get JPEGS, which are 8 bits. But even then the camera uses the full dynamic range and compresses the image to 8 bits

The dynamic range is the difference between the lightest and the darkest light a sensor can distinguish, after discarding the noise, measured in f stops.

The bits in the Image refer to the number of discrete steps of the A2D converter. Thus a 10 bit A2D will give 1024 steps, while the 16 bit give 64k steps for each colour.
Aroy is offline   Reply With Quote
Old 25th May 2011, 10:59   #7603
Senior - BHPian
 
Join Date: Dec 2010
Location: Ghaziabad/Hyderabad/Mysore
Posts: 1,416
Thanked: 313 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by Aroy View Post
Yes bracketing would do, but then it is difficult to get same view when action is fast (or when there is any action). Bracketing was in fashion with film cameras as you never knew if the shots were perfectly exposed, especially with slide film. With DSLR you can always view the Histogram and correct your exposure.

Dynamic Range varies
- MFDB : 10-13 stops
- DSLR high end : 9-12 stops
- DSLR medium end : 8-11 stops
- Small Sensors : 8-10 stops
The major problem is that if you do not use RAW (or do not have that option), you get JPEGS, which are 8 bits. But even then the camera uses the full dynamic range and compresses the image to 8 bits

The dynamic range is the difference between the lightest and the darkest light a sensor can distinguish, after discarding the noise, measured in f stops.

The bits in the Image refer to the number of discrete steps of the A2D converter. Thus a 10 bit A2D will give 1024 steps, while the 16 bit give 64k steps for each colour.

Why do you say this is OT? I thought this was the DSLR thread - sensor related stuff must be relevant.


you are right about the definition of dynamic range as the different between lightest and darkest a sensor can distinguish (when measured in f-stops, which is a logarithmic scale with each stop doubling the light)

If you talk to sensor designers, number of f-stop = number of bits of dynamic range.

What they do is they use an ADC after the sensor and then tell "12bit ADC" - the pixel sensor itself may have SNR/DR of only 8 bits (and in such a case the 4 lower bits coming from the ADC will be pure noise).

Normally you'll see that number of ADC bits (i.e. RAW bits) per pixel > number of f-stops the difference is at least one, and usually 2 or more.




I'm assuming by MFDB you mean Medium Format Digital Back. What kind of sensors are these guys using (CCD or CMOS?) Some years ago I was designing both, and CCDs had much better dynamic range and noise than CMOS (CCDs could do 16 bits easily, CMOS had to rely on tricks to get to 14). CCDs were damn expensive though, and there was no way DSLR revolution could have happened without CMOS.
vina is offline   Reply With Quote
Old 25th May 2011, 11:25   #7604
Senior - BHPian
 
Join Date: Aug 2010
Location: Delhi
Posts: 2,105
Thanked: 983 Times
Default Re: The DSLR Thread

Quote:
Originally Posted by vina View Post
What they do is they use an ADC after the sensor and then tell "12bit ADC" - the pixel sensor itself may have SNR/DR of only 8 bits (and in such a case the 4 lower bits coming from the ADC will be pure noise).

Normally you'll see that number of ADC bits (i.e. RAW bits) per pixel > number of f-stops the difference is at least one, and usually 2 or more.

I'm assuming by MFDB you mean Medium Format Digital Back. What kind of sensors are these guys using (CCD or CMOS?) Some years ago I was designing both, and CCDs had much better dynamic range and noise than CMOS (CCDs could do 16 bits easily, CMOS had to rely on tricks to get to 14). CCDs were damn expensive though, and there was no way DSLR revolution could have happened without CMOS.
The S/N ratio depends largely on the sensel (pixel) area, so a larger sensel will theoretically have better S/N ratio, hence better dynamic range. Modern designs have evolved to a level where the S/N for 5 micron devices is better than the older 9 micron devices. The noise reduction is mainly in the area of electrical noise, and to some extent thermal noise using better thermal designs. Further the sensel area with respect to the sensel spacing is increasing, increasing the signal. Of course you can cool the sensor and get lower noise, hence better dynamic range (as is done in astronomy)

MFDB is Medium Format Data Backs. Till date all of them are CCD base. The latest are the 80 MP backs from Phase One and Leaf (both same company now). I have read that Sony is targeting a large CMOS chip of around 120MP, and that both Nikon and Canon are getting 30MP CMOS.

As the signal from a sensor is Analog, there is no harm in increasing the number of bits in an A2D, provided the step size is above the noise threshold.
Aroy is offline   Reply With Quote
Old 25th May 2011, 11:34   #7605
BHPian
 
Join Date: Nov 2009
Location: Bangalore
Posts: 604
Thanked: 186 Times
Default Re: The DSLR Thread

Has anybody successfully downloaded nikon digitutor videos to hard disk?

The well know trick of copying the last big sized file from temporary internet files folder and renaming to flv does not work since NOTHING is downloaded to the temp directory after the video has fully played on the web-site.
WindRide is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
DSLR Video Discussion Sankar Gadgets, Computers & Software 129 18th August 2017 19:07
On a Temple Visiting Spree! Returned with only 1 wish. Need a DSLR! mclaren1885 Travelogues 23 27th July 2007 11:21


All times are GMT +5.5. The time now is 00:06.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks