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Rooky007
19th November 2012, 08:43 PM
Why the OMD has a minimum ISO of 200?? Surely they could of started at 100 or lower.

Could this be fix via a Firmware Update in the further?

It just that I was looking through some photos this evening and I had some cracking shots taken at 100 ISO on a Panasonic GF1 but that camera was not good above 1600 ISO though..

So wonder if any of your guys knows about the OMD not having a lower ISO such as 100?

Zuiko
19th November 2012, 08:55 PM
The sensor's base sensitivity is ISO 200. It would be possible to get an equivalent of ISO 100 from it, but it wouldn't improve image quality, in fact probably the reverse. The sensor could, of course, be engineered for a base of 100 but then high ISO wouldn't be as good. The only reason that you might need ISO 100 in practice is if you want to use a wide aperture, such as f1.8, on a bright day or a slow shutter speed. To get around this use a Neutral Density filter.

Rooky007
19th November 2012, 08:58 PM
The sensor's base sensitivity is ISO 200. It would be possible to get an equivalent of ISO 100 from it, but it wouldn't improve image quality, in fact probably the reverse. The sensor could, of course, be engineered for a base of 100 but then high ISO wouldn't be as good. The only reason that you might need ISO 100 in practice is if you want to use a wide aperture, such as f1.8, on a bright day or a slow shutter speed. To get around this use a Neutral Density filter.

So am I right in thinking there be very little between the 100 and 200?

In what ways would it make higher ISO poor if the sensor was engineered to work from 100 ISO?

I suppose that why the GF1 was poor at 1600 ISO and up as it started at 100?

PeterBirder
19th November 2012, 09:08 PM
Why the OMD has a minimum ISO of 200?? Surely they could of started at 100 or lower.

Could this be fix via a Firmware Update in the further?

It just that I was looking through some photos this evening and I had some cracking shots taken at 100 ISO on a Panasonic GF1 but that camera was not good above 1600 ISO though..

So wonder if any of your guys knows about the OMD not having a lower ISO such as 100?

This one has come up a few times recently and is related to sensor technology.
The basic "native" sensitivity of the OMD sensor is ISO 200 and it has, compared to previous Olympus cameras, far superior high ISO noise characteristics. If you were to make the sensor with a lower base ISO you would have to employ more amplification to obtain the high ISO sensitivity. Since any amplification introduces more noise and amplifies any existing sensor noise you would then loose the low noise high ISO performance. You can't have both I'm afraid. If you want to make long exposures in brighter light you can still use the established technique (from film technology) of ND Filters.

Regards.*chr

PeterBirder
19th November 2012, 09:11 PM
Ah, John can type faster than me.:D

Regards.*chr

Rooky007
19th November 2012, 09:16 PM
Thanks guys was just wondering that all coming from a Canon 7D.

But I must say I love the camera Ive got much better photos out of it than the 7D. Ive got a Lee Filter Kit so going to order a ring for it to fit onto the lens but till i settle on which Lens I am going to use for Landscape Ill hold fire.

Which lens you reckon I should get that wont break the bank for Landscape I though about the Panny 14MM

Zuiko
19th November 2012, 10:08 PM
Thanks guys was just wondering that all coming from a Canon 7D.

But I must say I love the camera Ive got much better photos out of it than the 7D. Ive got a Lee Filter Kit so going to order a ring for it to fit onto the lens but till i settle on which Lens I am going to use for Landscape Ill hold fire.

Which lens you reckon I should get that wont break the bank for Landscape I though about the Panny 14MM

When you had the Canon did you use just one focal length for landscapes or did you use a several primes or a zoom?

Seonnaidh
19th November 2012, 10:17 PM
Personally I tend to go no wider than 24mm or it's m4/3rds equivalent of 12mm due to
distortion problems. As readily noticed on my 'Opinions Required' thread.
I'm a great one for using lenses over 100mm for landscapes as I like to home in on wee bits of scenery.
I find the 12 -50mm 'kit' lens excellent as a general purpose lens including landscapes.
My example 'sweetspots' at f8/f11 and is a much better lens than most people give it credit for.
A lens I've borrowed and fallen in love with for landscapes is the Panny 25mm .

Rooky007
19th November 2012, 10:18 PM
When you had the Canon did you use just one focal length for landscapes or did you use a several primes or a zoom?

I had the 17-40 L Lens for Landscape most of it was between 17 - 20 but i think i can live with a prime I just want a sharp lens.. Ive the kit lens if I want Flexibility sometime

Rooky007
19th November 2012, 10:47 PM
Personally I tend to go no wider than 24mm or it's m4/3rds equivalent of 12mm due to
distortion problems. As readily noticed on my 'Opinions Required' thread.
I'm a great one for using lenses over 100mm for landscapes as I like to home in on wee bits of scenery.
I find the 12 -50mm 'kit' lens excellent as a general purpose lens including landscapes.
My example 'sweetspots' at f8/f11 and is a much better lens than most people give it credit for.
A lens I've borrowed and fallen in love with for landscapes is the Panny 25mm .

I've heard so many good reviews about the 25mm price puts me off

Zuiko
20th November 2012, 12:27 AM
I had the 17-40 L Lens for Landscape most of it was between 17 - 20 but i think i can live with a prime I just want a sharp lens.. Ive the kit lens if I want Flexibility sometime

Well, if your most used focal lengths with the 7D were 17-20mm, that equates to 13-15mm on the E-M5. The Panasonic 14mm sits bang in the middle, so if you want a single prime that's the one to get. :)

Seonnaidh
20th November 2012, 09:50 AM
A good lens is always worth saving for. It is a real investment.
As someone said on the forum a little while ago camera bodies are disposable, glass is for life.
Just save for a wee while longer and get the lens you really want. In the long run you won't regret it.

Greytop
20th November 2012, 10:10 AM
Just to throw a spanner in the works, you could consider the excellent ZD 14-54 MK2 4/3rds lens with a MMF-2 or 3 adapter (MMF-3 makes more sense as it's weather and dust resistant).
The 14-54 MK2 (http://www.olympus.co.uk/site/en/c/cameras_accessories/digital_slr_cameras_accessories/dslr_lenses_adapters/zuiko_digital_14_54mm_12835ii/zuiko_digital_14_54mm_12835ii_main.html) is a fast f/2.8 to 3.5 and very sharp zoom offering a field of view equivalent to a 17.5 to 67.5 on your old Canon system. It balances well on the E-M5 with the grip fitted and to be honest matches or surpasses pretty much most of the better m4/3rds glass currently available, certainly on the zoom front. The only slight down side is that it's not particularly fast at focusing and it balances the scales on the slightly large side (but not overly so). You could pick up a very good second hand example for under 300 + the converter.

Zuiko
20th November 2012, 10:16 AM
Just to throw a spanner in the works, you could consider the excellent ZD 14-54 MK2 4/3rds lens with a MMF-2 or 3 adapter (MMF-3 makes more sense as it's weather and dust resistant).
The 14-54 is a fast f/2.8 to 3.5 and very sharp zoom offering a field of view equivalent to a 17.5 to 67.5 on your old Canon system. It balances well on the E-M5 with the grip fitted and to be honest matches or surpasses pretty much most of the better m4/3rds glass currently available, certainly on the zoom front. The only slight down side is that it's not particularly fast at focusing and it balances the scales on the slightly large side (but not overly so). You could pick up a very good second hand example for under 300 + the converter.

If you go this route be sure to get the MkII version rather than the MkI, because it does focus faster (although still slow by native MFT lens standards).

snaarman
20th November 2012, 10:39 AM
If you go this route be sure to get the MkII version rather than the MkI, because it does focus faster (although still slow by native MFT lens standards).

Yes. This is my preferred combo - the 14-54 MK2, the adapter and the E-M5 with half grip.

The lens is reasonably bright and quite sharp. It is great for general landscape and looks "right" on the camera where many m4/3 lenses can look a bit small (not that the look of a lens on a camera matters really..)

Pete

Ulfric M Douglas
20th November 2012, 11:43 AM
The sensor's base sensitivity is ISO 200. It would be possible to get an equivalent of ISO 100 from it, but it wouldn't improve image quality, in fact probably the reverse.
In my experience (and ironically the unknowing experience of most Olympus users) this is not at all true.
Let's imagine for a moment the e-600 has a base ISO of 200 ... same as the e-M5. (Actually 'similar' since the 'real' ISO figures are different to what either camera displays.)
Let's also imagine it produces better (a subjective observation, sure) ISO100 Jpegs than ISO200 Jpegs. More bright cloud detail, less sky noise : observed by many users over the years.
Maybe those who have dug deeply into the 12mpx sensor behaviours can corroborate my own observations, the search function isn't too helpful but this has all been discussed a long time pre-e-M5 and the findings were interesting.

IF the e-M5 did have an ISO100 Jpeg option it would certainly be useful : even useful enough to gain a load of sales to those, like me, who like Jpegs from a wide-open lens on a bright day without ND filters on it.
I'm sure that it would lose some dynamic range ... so what? For Jpeg users it wouldn't be crippled like it is right now.

mike_j
20th November 2012, 11:46 AM
Going back to ISO - my Leica M8 has a minimum of 160 and I quite often use a x4 ND filter to cut the light down when using studio flash so that I can work at a wide aperture.

Last night at a club studio session I couldn't get the OM-D below f11 which is into diffraction territory. The M8 was at f5.6 which is near optimum.

I had no control over the lights so couldn't reduce them.

Jetset95
20th November 2012, 12:24 PM
You might like to give a little more info about your last post Mike_J - first thing I'm thinking is what mode were you shooting in P, A, S or M? If not the former why not bump up the SS to open the aperture? Sorry if your lack of info meant that this was stating the blooming obvious and you would have if you could, but without the EXIF data we can't tell. Thanks, James