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Following a hint on increasing the ISO on the d70 to 3200 and 6400, I decided to give it a go at the NZ Warriors vs South Sydney Rabbitohs Game.

I set mine to Aperture priority and set it to the widest aperture (5.6) for a 70-300mm.

Set the Exposure Compensation to -1 or -2 (3200 or 6400 equivalent). This makes a normally metered shot at ISO 1600 from 1/80 to 1/320 for ISO 6400, which is fantastic for sports .

The results are fantastic, just needs a little tweak in photoshop.

==>Levels==>Auto Contrast==>Auto Colour==>Curves==>Noise reduction software like Noise Ninja<==

All images take at ISO 1600 w/ Exposure compensation -2 = ISO 6400
All images have been reduced to 20%

Welcome to the forum Bountybala! This is an intriguing posting, the pictures look good but I don't really understand how exp comp of - 2 is equivalent to ISO 6400.

I would have thought it would just underexpose the photo , the worst kind of situation one can get when using 1600 ISO. Is there any noise visible when you look at the photo at 100 or 66%?

Link.

It's like "pushing/pulling" film (remember that stuff?!!). Basically you are underexposing but then you push the exposure up two stops and effectively have captured at 6400 ISO (as far as I can understand).

The drawback is mega noise and lack of shadow detail, hence the Contrast/Curves and Noise work bounty did on the pics.

Next time you're reading the Sports section in the paper, have a look at how crappy the night shots of the rugby are when they're blown up to a 1/4 page! That's cos the photog has either used super sensitive film (ISO 1600-3200 - they'd be using wider aperture lenses so wouldn't require as fast as this case) or they've underexposed they're film and had it processed to compensate (ie overexposed to bring the underexposure up!)

Confused yet? I am!

Liam =]

Nice compositions. Don't know whether it's my old CRT lacking brightness or are these a bit too dark?

Cheers
Alex

Nah, they're a bit dark Alex. Don't adjust monitor

Thanks Darryl. I work from an ancient 5 yr old computer (yet to save for an upgrade) and I know my CRT is notorious for being a bit too dark.

I don't think I can adjust it any further. I maxed out on brightness and am still a bit too dark, well, compared to my wife's laptop's LCD, which may be just a bit too bright.

Thanks
Alex

sorry about the quality of the image, Nth Sydney Oval has lighting which is terrible. Further to what has been said the Lack of details in shadows is one i must accept if i do not want overly noisy image. however with careful tweaking i am sure it can be rectified

bountybala wrote:sorry about the quality of the image, Nth Sydney Oval has lighting which is terrible. Further to what has been said the Lack of details in shadows is one i must accept if i do not want overly noisy image. however with careful tweaking i am sure it can be rectified

Not to worry. I think the darkness is also compounded on my old CRT too. They are very good images composition wise.

Cheers
Alex

Bountybala,

Welcome aboard.

I do not mean to "rain on the parade (footy match??)" , but all that this technique will acheive in digital is under exposure. To try to pull the exposure back up has one major problem. That problem is the way digital captures and stores information.

Consider the histogram. At the far right (highlights) there will be 2048 discreet levels of data recorded, 1 stop down (midway between this point and the centre of the histogram) there will be 1024 levels recorded. At the midpoint of the histogram 512 levels. One stop further down 256 levels, and at the left of the histogram 128 levels.
As you can see there is far more information stored to the right of the histogram. This is the reason for "expose to the right". Working in the LHS of the histogram, there is far less information recorded. It is impossible to pull the fine detail from the left of the histogram because the information simply does not exist. The result is lost detail and noise. The noise is already there in modest amounts, PP of this nature simply amplifies it.

2 stops is a loong way for a digital sensor which appears to me to have a DR of a little more than 4.5 stops - some say it is 6 or more stops. Consider mid grey, white and black. Under expose grey by 2 stops and grey falls very close to the bottom of the histogram, white somewhere close to the middle, but everything below a point that is just below mid grey is outside of what the sensor is able to capture. It would be rendered black with little to no detail. The other thing is that there will only be 128 levels recorded at mid grey, which happens to be where most skin tones are at.
This "film technique" effectively reduces the sensors DR and detail recorded in a time where we are all trying to get more (flashes, multiple exposures....)

As I understand it (I have never been a film shooter, although I am heading that way for some applications), some film is as limited as digital, others have much latitude for push/pull processing (2 or more stops), and for those films the image information is there but the density of the information is low. Hence the processing technique to increase the density. However, there is a limit to how far this technique can be taken before "noise" is introduced.

Having said that, your photos came up quite nicely, although a little dark, but you were shooting at night, so the images would be fairly true to what you would have seen, and I suspect that the reduction in size for web has gone some way towards cleaning up any visible noise and detail problems.


Cheers

Matt

Having tried both the push / pull techniques on both film and digi slr's, I have to say that getting 6400 out of the D70 sensor is probably pushing it to its extreme limit... your images may be able to look decent, but you'll honestly be bloody lucky to get a good A4 print out of them with the amount of grain you'd be producing, and to be frank, really no amount of fractal interpolation would be able to help you here.

Film tends to be much more versatile (some film... a lot of it isn't, of course) in regards to the push / pull method.

Bountybala,
welcome to the forum. The only criticism I can make is that all the shots are of my beloved Rabbitohs looking like they're being belted...please in future edit your selections more carefully

Frank

I wonder what the limit will end up being for low light shooting with digital sensors on prosumer cameras? I suspect low light is one area where digital will truly shine,(forgive the pun), against film.

Am I wrong to think that digital video cameras have been shooting in very low light for some time? 1 Lux I think my video camera can capture images at...

And in Raw Shooter Essentials aren't there a couple of sliders that make up for noise?

I think some cameras have ways of slowly processing low light images - perhaps they also take a snapshot of the way the sensor looks without an image and then subtract any errant pixels from the low light pic?

Does anyone know that American photographer in the 70's who took a lot of IR flash pics of his friends in nightclubs? There will be a lot more of that
sort of sureptitious shooting going on if the cameras get as good as I think they might in low light.

Tell me if I'm being dim.....

Bob