dear all, I'm in the considering to sell my old dear EOS 5D, to buy the new one.But I searched over the net more informations the AUTO ISO but none of them explains the working process enough clearly. If I understand right, the 5D Mark II now features an automatic ISO option where the camera selects the sensitivity (in the range ISO 100 - 3200). In Auto, Program and Aperture Priority the camera attempts to maintain a minimum shutter speed of 1/focal length (hence with a 24 mm lens it will try to maintain 1/25 sec or faster). In manual mode Auto ISO is fixed at ISO 400. BUT It's NOT possible to manually select a maximum ISO within the Auto ISO range, or, far more important, a minimum shutter speed (why!?!?).In other words it's not possible to work in a (kind of) ISO priority mode. Which could be really really useful!So my questions are the following two:if I work in Shutter Priority how the camera will work on the Aperture/ISO pair? Will it open progressively the Aperture till it can maintain the ISO fixed? or, on the contrary will it raise the ISO while maintaining the same Aperture?if I work in Aperture Priority is there any way to control the shutter speed if I need a minimum faster than 1/focal length (e.g. for fast subjetcs which I used to shoot at)?Et voilà, who knows how it works?TIA and have a nice weekendAzi

This has been discussed at length in other [huge] threads so you might look around for more detail. The quick answer is that there appears to be no way to configure the 5D2 for true ISO priority operation or to have the camera shift ISO at any shutter speed other than 1/focal length. Pretty worthless for my purposes.

yep it's a simple logical thing but canon doesn't want to give away all their pro level features on a non pro camera. really bugs me too.tlinnwrote:This has been discussed at length in other [huge] threads so you might look around for more detail. The quick answer is that there appears to be no way to configure the 5D2 for true ISO priority operation or to have the camera shift ISO at any shutter speed other than 1/focal length. Pretty worthless for my purposes.

thanks. I will search around for finding the huge threads you refer to. Anyway, if I'm right, even in the EOS 1D series these kind of functions are NOT present, so it's not because Canon want to give these nicities only in the PRO bodies.

oh it's there in the 1D series. it's a custom function that you can lock what your minimum and maximum shutter is. i think it can do apertures as well.Azimuth46wrote:thanks. I will search around for finding the huge threads you refer to. Anyway, if I'm right, even in the EOS 1D series these kind of functions are NOT present, so it's not because Canon want to give these nicities only in the PRO bodies. --

They could easily implement true Auto Iso, but they don't. It's upsetting and stupid of them. I'm considering a switch to Nikon. -- .

oh I see. Can you tell the exact custom fucntion where I can find it.TIA

I had the same question a while ago. Here is a link to the response I got: http://forums.dpreview.com/forums/read.asp?forum=1032&message=29033008I think the EOS 5D II also has custom functions that are similar to the ID series.However, I just wish the 5DII had a simple auto ISO function in manual mode.Ali.

ali20wrote:I had the same question a while ago. Here is a link to the response I got: http://forums.dpreview.com/forums/read.asp?forum=1032&message=29033008I think the EOS 5D II also has custom functions that are similar to the ID series.However, I just wish the 5DII had a simple auto ISO function in manual mode.That might take a programmer 10 minutes to implement. Perhaps a bit longer if they left high-ISO open-ended and needed to deal with gamma issues at extreme ISOs, for the JPEGs. The way I envision a true TAv-priority mode, there is no point in having an upper limit to ISO. The camera should go to ISOs in the millions, if need be, because TAv means user-chosen Tv and Av, and there's no point in having a JPEG/review image too dark to see, by having an upper limit.

This thread explains why this subject just goes on & on:http://forums.dpreview.com/forums/read.asp?forum=1036&message=29403317 -- http://www.flickr.com/photos/14381217@N03/ Pardon my spelling, I'm a retired COBOL programmer.

We now have 40d/450d/50d/5d2 with "auto iso" where we get 1/fl and no way to increase the margin or change the min. shutter speed.on the 1-series you have iso-safety shift instead where you can use it in Av or Tv mode and set the allowable shutter speeds (only up to 1/60) and allowable apertures. So you can use Tv mode and allow the aperture to be opened up until wide open and the iso will then increase.butno fully iso-priority.Nikons is slighly better in that you can set a min shutter speed, but, you cant change it short of going into the menu - but it does work in M mode....hey -hoperhaps on the next cameraAzimuth46wrote:dear all, I'm in the considering to sell my old dear EOS 5D, to buy the new one.But I searched over the net more informations the AUTO ISO but none of them explains the working process enough clearly. If I understand right, the 5D Mark II now features an automatic ISO option where the camera selects the sensitivity (in the range ISO 100 - 3200). In Auto, Program and Aperture Priority the camera attempts to maintain a minimum shutter speed of 1/focal length (hence with a 24 mm lens it will try to maintain 1/25 sec or faster). In manual mode Auto ISO is fixed at ISO 400. BUT It's NOT possible to manually select a maximum ISO within the Auto ISO range, or, far more important, a minimum shutter speed (why!?!?).In other words it's not possible to work in a (kind of) ISO priority mode. Which could be really really useful!So my questions are the following two: if I work in Shutter Priority how the camera will work on the Aperture/ISO pair? Will it open progressively the Aperture till it can maintain the ISO fixed? or, on the contrary will it raise the ISO while maintaining the same Aperture? if I work in Aperture Priority is there any way to control the shutter speed if I need a minimum faster than 1/focal length (e.g. for fast subjetcs which I used to shoot at)?Et voilà, who knows how it works?TIA and have a nice weekendAzi --

greg_thurtle_ukwrote:butno fully iso-priority."ISO-priority" means you set the ISO, and the camera chooses the rest. We already have that. It's called "P" mode.

"ISO-priority" means you set the ISO, and the camera chooses the rest. We already have that. It's called "P" mode.Good point. This occurred to me too, although folks seem to understand what is being conveyed. Pentax really has it correct with "TAv" priority.

It sounds like a good idea; in practice, it really isn't necessary. I'm not sure it's even convenient. In fact it may not even be a good idea.

"n00b"?Why does Auto-ISO ignite such passionate dislike, which disintegrates into "I'm a better photographer than you/ I have more chest hair" arguments.Many times, IknowI want shutter speed of 1/640, aperture of 2.8, and nothing else. Creatively, ISO at times does little for me (DOF and shutter speed do!), so in certain situations (sports, indoor theatre, outside moving from shade to bright area following a very fleeting and fast subject) I only care that the computer does the dummies's job of tweaking the ISO from 200 to 800 (which artistically changes NOTHING if noise levels are stable) to obtain the correct exposure FASTER THAN HUMANLY POSSIBLE. If I need to manually change ISO, it will take a minimum of 0.5 seconds to do it on the most ergonomically designed of interfaces. (I probably take more like a second or two). There are times when that "lag time" HINDERS my ability to get the shots I want.So, Could I change ISO myself? YES! a monkey can do it! Move the numbers until the little arrow is at "0". That is why computers exist!Of course, many situations arise where you need to force ISO values, such as Landscape with ISO 25, 50, maybe 100, and other situations likely involving larger apertures in combination with high shutter speeds, etc, which a computer program PREDICTABLY would avoid. Then you switch the ISO value manually to allow the shutter speed/aperture combos you require. It is up to you to know your camera well enough to predict how it will react, and when you need to "take the wheel". If you don't, of course, auto-anything will scare you!-Raul

I will add this:I believe auto iso should really only be in: 1) full auto modes2) a TvAv type mode (OR 'M' mode with ONLY ISO on 'Auto' and full control of Shutter speed and f stop for the user)Av and TV mode with Auto-ISO is messy and difficult to manage, and P mode with Auto-ISO is essentially AUTO with the ability to shuffle between equivalent exposures for a randomly picked ISO value. Anybody with any algebra experience knows two or three (shutter speed, F stop, and ISO computer picked) variables in one equation is BAD! Very difficult to predict what shutter speed the computer will pick for F5.6 when ISO bounces 200 to 400 then 100. Again, I don't have to CARE what the ISO per se was, only that it makes predicting the camera's behavior difficult. -- -Raul

joebloewrote:It sounds like a good idea; in practice, it really isn't necessary. I'm not sure it's even convenient. In fact it may not even be a good idea.I think it's one of the most fantastic ideas and could be developed and implemented much further just in to a separate Shutter+Aperture priority shooting mode.I used to think an Auto ISO feature would be a noob thing too but if you're shooting in dodgy (I mean dynamic) lighting situations with a lot of action, you can't predetermine an ISO. In the following situation, the light amounts varied from 1/10 to the 1/5000 chosen for this particular shot:http://flickr.com/photos/genotypewriter/2682033136/So I repeat... Auto ISO is not a n00b feature... unless there's a way to work around this... and if you can tell me such a way, I'll gladly admit that I'm a noob.GTW -- http://www.flickr.com/genotypewriter

joebloewrote:It sounds like a good idea; in practice, it really isn't necessary. I'm not sure it's even convenient. In fact it may not even be a good idea.In the 5.5 years I have been using digital cameras, this has presented itself as the thing I need most out of my cameras. I have to try to work around the lack of this mode in various ways, all of which result in lots of ruined images; f/40 shots of hawks in flight; 1/10 second blurs at 560mm, etc, etc.The most important thing to me when shooting, most of the time, is the shutter speed, and the f-stop. ISO is a distant second.

well all you guys that want TAV should write the review of 5d2 in canon websote and request it otherwise it will never be implemented

Teosaxwrote:well all you guys that want TAV should write the review of 5d2 in canon websote and request it otherwise it will never be implemented --sad, sad, very sad!Azi