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Grumpy Hec
30th October 2013, 07:50 AM
One of the slight niggles with the spec of the EM-1 is the native ISO of 200. As someone who likes to play with slow exposures one of the things on my wish list for the new camera a long time ago was at least native ISO100 or better still ISO50. I know that's exceptionally unlikely to happen but the wish remains nonetheless.

So getting back to reality I'm interested in low ISO performance and what that actually means on the EM-1.

> is it actually ISO100
> do you get the sort of extra quality at 100 over 200 you would expect from say my E3?
> apart from slower shutter speeds is it, in real life terms, worth using

I can see me having to further expand my collection of ND filters and /or use my circular polariser to get a couple of stops. That's a shame as sticking extra bits in front of expensive and expertly crafted glass always seems like an anathema to me.

This question is in eager anticipation of my camera arriving on Friday which is my current understanding. Needless to say the law of SOD will be as reliable as always and it will turn up after I've left for Yorkshire at lunch time. :(


cheers

Hec

StephenL
30th October 2013, 08:31 AM
Check this post, Hec. I found 100 eminently useable.

http://e-group.uk.net/forum/showthread.php?t=29738

Grumpy Hec
31st October 2013, 07:45 AM
Thanks Stephen. Looks from that and your comments that Low ISO is very usable.

I still wish that new sensors had as much work put into them on low ISO as high ISO with low noise. Apart form the sheer quality, and the avoidance of having to put filters in front of your HG glass so quickly, slower shutter speeds are an interesting area in their own right. I guess it's not as marketable as high ISO capability.

Imagine though being able to use ISO 50 or 25 as we used to in film days.

So for the EM-3 (I assume there will not be an EM-2) ISO range of 25 - 25600 with minimal noise at the high end and silky smooth detail and colour rendition at the low end. *yes

Hec

Bikie John
31st October 2013, 09:58 AM
Silky smooth details and colour rendition would be nice at the high end, too!

John

Ian
31st October 2013, 10:03 AM
If I remember rightly, back in the film days were were all moaning about being limited by 25 and 50ASA film in order to get fine grain! :D

Remember, the E-P5 and E-M1 now go to 1/8000th with ISO 100. Not many SLRs in the affordable range back in the 80s or even 90s went above 1/2000th and 1//8000th at ISO 100 is the same EV as 1/2000th at ISO 25.

Ian

Thanks Stephen. Looks from that and your comments that Low ISO is very usable.

I still wish that new sensors had as much work put into them on low ISO as high ISO with low noise. Apart form the sheer quality, and the avoidance of having to put filters in front of your HG glass so quickly, slower shutter speeds are an interesting area in their own right. I guess it's not as marketable as high ISO capability.

Imagine though being able to use ISO 50 or 25 as we used to in film days.

So for the EM-3 (I assume there will not be an EM-2) ISO range of 25 - 25600 with minimal noise at the high end and silky smooth detail and colour rendition at the low end. *yes

Hec

photo_owl
31st October 2013, 12:17 PM
200 has been the native ISO for a fair time now - since the 12MP sensors

In practice the DR is so improved now the uae of 100 is still an improvement in every way

If you want 50 you will need an e400 :)0

Grumpy Hec
31st October 2013, 12:53 PM
If I remember rightly, back in the film days were were all moaning about being limited by 25 and 50ASA film in order to get fine grain! :D

Remember, the E-P5 and E-M1 now go to 1/8000th with ISO 100. Not many SLRs in the affordable range back in the 80s or even 90s went above 1/2000th and 1//8000th at ISO 100 is the same EV as 1/2000th at ISO 25.

Ian

You are absolutely correct of course but as technology moves on so expectations and the wish list expand.

I admit that in this respect I am like a spoiled child simply wanting more and wanting it now :D

One day I may grow up *nono

Hec

Grumpy Hec
31st October 2013, 12:54 PM
Silky smooth details and colour rendition would be nice at the high end, too!

John

Absolutley

cliff
31st October 2013, 08:54 PM
Hi Hec, don't know if this shot is of any help to you, it was an "accidental":o 60 sec exposure on day one with the M1 but I thought it interesting enough not to delete ISO 200 F7 LF jpeg ooc
the black bits look pretty clean
http://www.e-group.uk.net/gallery/data/500/1-PA160041.JPG

hope you get your one on fri afore you go *chr Cliff

Peter_Hartland
31st October 2013, 10:02 PM
I had reservations about the low ISO, until yesterday when my mate I was out shooting at Westonbirt showed me a number of images he had taken at Low ISO (partically has it set as std) which is about ISO 100, small drop of in DR but images were extremely good. Having seen his images I would have no hesitation using Low ISO on the M1

David M
31st October 2013, 10:03 PM
But what happens when you want a slower shutter speed for some motion blur. With the limits of a base ISO of 200 and diffraction you can't without ND filters. But what about all the lenses out there that can't take filter?

Zuiko
31st October 2013, 10:33 PM
Hi Hec, don't know if this shot is of any help to you, it was an "accidental":o 60 sec exposure on day one with the M1 but I thought it interesting enough not to delete ISO 200 F7 LF jpeg ooc
the black bits look pretty clean
http://www.e-group.uk.net/gallery/data/500/1-PA160041.JPG



Delete it? :eek: Don't you dare! :mad:

I love it! *chr

DavyG
31st October 2013, 10:52 PM
Hi Hec, don't know if this shot is of any help to you, it was an "accidental":o 60 sec exposure on day one with the M1 but I thought it interesting enough not to delete ISO 200 F7 LF jpeg ooc
the black bits look pretty clean
http://www.e-group.uk.net/gallery/data/500/1-PA160041.JPG

hope you get your one on fri afore you go *chr Cliff

That is an excellent pic, would you mind explaining how it was achieved?

Thanks,

Dave

Ralph Harwood
1st November 2013, 12:29 AM
But what happens when you want a slower shutter speed for some motion blur. With the limits of a base ISO of 200 and diffraction you can't without ND filters. But what about all the lenses out there that can't take filter?

Hi there David!

Just a silly question, but couldn't you use the high speed shooting mode at ISO 100 with 10 frames and stack them in photoshop? Or would that give a less than smooth blur?

Or there is the modified (ok butchered slightly) mmf2 with space for a 32mm filter we discussed in another thread? I haven't tried making one yet but it does look possible.

Cheers,

Ralph.

David M
1st November 2013, 12:45 AM
In the example I posted in the other thread it wouldn't work as the ripples in the water wouldn't align. The ND filter in an MMF only works if you've got an m4/3 body.

Zuiko
1st November 2013, 12:59 AM
The base sensitivity is what it is and anything higher or lower requires some sort of electronic adjustment, which inevitably means a degree of compromise in quality. However, this compromise is getting progressively less as sensor technology improves and most of us are happy routinely using ISO 1600 with the latest 16mp sensors when conditions make it necessary. So why not make available a 3 stop shift in the other direction, i.e. down to ISO 25? Of course, under normal circumstances we would continue to use the ISO 200 base for optimum quality but ISO 100, 50 or 25 would certainly be worth the small sacrifice in quality when a slow shutter speed and/or wide aperture was required and would definitely be preferable to using an ND filter.

cliff
1st November 2013, 01:13 AM
That is an excellent pic, would you mind explaining how it was achieved?

Thanks,

Dave

Thanks Dave,
I was going to take a pic of the moon over the water at portsmouth sea front it was dark and I had not noticed that the aperture was set to 7.1, clicked the shutter thinking I was on f1.8, with the 17mm, after a few seconds realised what had happened and so pointed the camera at the available light sources, cars, street lights, did a swirl at the moon and then I herd the shutter close and watched it write to the card for about another 60 seconds (sandisk pro :rolleyes: 16gb 95mbs) saw the shot and smiled :) *chr Cliff

Ralph Harwood
1st November 2013, 01:15 AM
In the example I posted in the other thread it wouldn't work as the ripples in the water wouldn't align. The ND filter in an MMF only works if you've got an m4/3 body.

Both very good points David - I had thought that the ripples would move slowly enough that photos taken a tenth of a second apart might not have that issue, but you are almost certainly right.

Anything that Olympus make now will be micro 4/3rds - Ian has confirmed this in other threads - so asking for slower iso in a new camera would be only for micro 4/3.

However Johns suggestion of being able to move the whole iso range by 3 stops could be possible simply by adding an LCD layer into the hot-mirror in front of the sensor. It could then be switched on or off at will adding an 3 stop ND (or more - my LCD welding mask goes up to 13 stops as far as I can tell). Obviously this would add cost and may cause issues with light being polarised (it would work in a similar way to the variable ND filters) but nothing that Olympus couldn't work around given time and budget - it would certainly be a USP as I haven't heard of any other manufacturer doing anything like this.

It would really be down to demand then, but with Olympus looking forward and hoping to promote it's new lenses (the majority of which can be used with screw in filters) they may feel that it is not economically viable.

On another note - looking at my OM - 4/3 converter I could certainly fit a filter inside there as it is a round hole, so that maybe you could use one with your OM 350mmf2.8?

Cheers,

Ralph.

Grumpy Hec
1st November 2013, 06:55 AM
Hi Hec, don't know if this shot is of any help to you, it was an "accidental":o 60 sec exposure on day one with the M1 but I thought it interesting enough not to delete ISO 200 F7 LF jpeg ooc
the black bits look pretty clean
http://www.e-group.uk.net/gallery/data/500/1-PA160041.JPG

hope you get your one on fri afore you go *chr Cliff

That's a great accidental shot. As you say it looks very clean.

As to the arrival. It's en-route from the "East Midlands facility" heading, I presume, for the Ipswich depot prior to coming to Mersea. It will be touch and go about arriving by 12:30 which is my drop dead time for leaving. The main thing is that it's on it's way at last. I have my E3 for the weekend so it's not the end of the world.

Needless to say though I want it NOW :)

Hec

Grumpy Hec
1st November 2013, 07:02 AM
But what happens when you want a slower shutter speed for some motion blur. With the limits of a base ISO of 200 and diffraction you can't without ND filters. But what about all the lenses out there that can't take filter?

At the moment anyway I am/will be using 43 lenses so putting my filters on the front is not a problem. I will almost certainly slowly migrate to m43 as the "pro" series settles in and I assume they will all have filter threads. All I'll need is the appropriate size adapter for my Hi-Tech system holder.

Anybody know abut the 12-40?

My basic ultimate wish remains though for a native lower ISO capability to expand the "pro" feature set of the EM line.

Let's get it into perspective though. This is only my personal wish and I suspect I'm in the minority. Fair enough.

cheers

Hec

photo_owl
1st November 2013, 12:29 PM
Anything that Olympus make now will be micro 4/3rds - Ian has confirmed this in other threads - so asking for slower iso in a new camera would be only for micro 4/3.

Ralph.

I doubt that Ian did say that - it's certainly not what Olympus have said. They didn't say there would be, but they did say they weren't saying that there wouldn't be.....

He may have said that there won't be any more 43 lenses - but that's another matter.

StephenL
1st November 2013, 12:56 PM
ISO 100 certainly isn't the E-M1's native base setting, but in my amateur un-pixelpeeped view it's eminently use-able. It takes good photos for me, and that's all I'm interested in. After all, anything over ISO 200 is a compromise as well.

blu-by-u
1st November 2013, 02:27 PM
Just wondering, What if you stack a EC20? that would make you loose 2 stops of light, would that be of any difference?

photo_owl
1st November 2013, 06:58 PM
At the moment anyway I am/will be using 43 lenses so putting my filters on the front is not a problem. I will almost certainly slowly migrate to m43 as the "pro" series settles in and I assume they will all have filter threads. All I'll need is the appropriate size adapter for my Hi-Tech system holder.

Anybody know abut the 12-40?

My basic ultimate wish remains though for a native lower ISO capability to expand the "pro" feature set of the EM line.


cheers

Hec

the filter for the 12-40 is 62mm

my only issue with your wish is that you can only have one 'native' ISO and generally speaking it's a lot easier to reduce light (filter) than add it (lighting/flash etc).

to achieve the equivilent of an ND8 in the native ISO would make the camera
poor for any moving subject at all....etc

basically you need to be able to add filters for longer shutter exposures on 43 sensors anyway because you are pretty restricted in the use of smaller apertures!

DavyG
1st November 2013, 09:38 PM
Thanks Dave,
I was going to take a pic of the moon over the water at portsmouth sea front it was dark and I had not noticed that the aperture was set to 7.1, clicked the shutter thinking I was on f1.8, with the 17mm, after a few seconds realised what had happened and so pointed the camera at the available light sources, cars, street lights, did a swirl at the moon and then I herd the shutter close and watched it write to the card for about another 60 seconds (sandisk pro :rolleyes: 16gb 95mbs) saw the shot and smiled :) *chr Cliff

Thanks for the explanation Cliff.

I'll give this a try at some point, I'd be very happy if I could produce an image like yours,

Dave

jmunkki
1st November 2013, 10:27 PM
The time spent "writing" isn't actually writing time. For really long exposures, digital cameras tend to actually do two exposures. First, they expose with the shutter open and then they expose a second frame with the shutter closed. The second exposure can be used to determine which pixels are noisy and how much noise they have added to the first photo.

Sensor noise is affected by temperature and sensors tend to deteriorate slightly over time, so while a calibration done every few months or even back at the factory might be good enough for shorter exposures, for long exposures it's much better to get noise data from a dark exposure of the exact same duration as the original.

The actual card write probably took a fraction of a second.

David M
1st November 2013, 10:45 PM
I like the idea of mounting a ND in an OM to 4/3 adapter, something that had never occurred to me. I wonder if the focus would shift as you'd have to focus and compose before installing the filter.

Ralph Harwood
1st November 2013, 11:08 PM
Hi there David!

I had the tape measure out earlier and my OM to 4/3 had an internal measurement of about 46mm, so a filter with a smaller thread of about 43mm or so should just drop in - a couple of turns of insulation tape taking up any slack and making it light tight. You would have to be careful to ensure that the rear element of the lens doesn't touch the filter, but when I have checked on a couple of my lenses they don't appear to protrude that far.

With regards to focussing I would think that there would be a small effect in adding a layer of glass where the lens would normally be focussing through air, but I would think that it would be consistant at any distance, so much the same as lenses used to have an IR mark you may well be able to make a "filter fitted" mark and focus without the filter and then adjust to the mark.

If you do have a go I'd be interested to hear how you got on.

Photo owl - I stand corrected - my interpretation of what was said was that there would be no more native 4/3 bodies but lenses makes more sense.

Cheers,

Ralph.

David M
1st November 2013, 11:32 PM
The drop in filter on the 350mm is behind all the lens elements at least an inch deep in the lens so there's no clearance issue. The OM 1.4x-A protrudes into the rear of compatible lenses about a quarter inch. I had to measure some of my lenses before testing the 1.4 on them.