stevebuk Posted July 12, 2016 Share #1 Posted July 12, 2016 Advertisement (gone after registration) Hi all, Sorry if this a daft question, but I am struggling to see the relevance of the exposure dots and triangles when in manual mode with auto iso. I have no issue with them and how they work generally, but with auto-iso it often tells me I need to increase / decrease exposure, but why? If I just ignore it, it works fine and bumps the ISO to where it needs to be. Do they relate to base iSO or am I missing something? Many thanks Steve Link to post Share on other sites More sharing options...
Advertisement Posted July 12, 2016 Posted July 12, 2016 Hi stevebuk, Take a look here M9 and auto-ISO dots and triangles.... I'm sure you'll find what you were looking for!
Gregm61 Posted July 12, 2016 Share #2 Posted July 12, 2016 From what I have experienced, the finder will show a dot if you have any amount of exposure compensation dialed in. Setting that back to zero will eliminate the dot if that's what is happening. You may also see a dot of the system is hitting the ceiling/max ISO to be used you have set in your auto ISO setup, or the lighting may be beyond the ISO range of your current shutter speed and aperture combination. There's definitely something the camera is trying to tell you in using those symbols. Link to post Share on other sites More sharing options...
pedaes Posted July 12, 2016 Share #3 Posted July 12, 2016 Hi all, ......, but with auto-iso it often tells me I need to increase / decrease exposure, but why? If I just ignore it, it works fine and bumps the ISO to where it needs to be. Do they relate to base iSO or am I missing something? Many thanks Steve Because the exposure meter is more accurate than ISO "stops" give you? You have more accuracy on the dials with between whole "stops" to fine tune to exact exposure. The triangles indicate which way to turn dials - speed or aperture. Link to post Share on other sites More sharing options...
stevebuk Posted July 12, 2016 Author Share #4 Posted July 12, 2016 Because the exposure meter is more accurate than ISO "stops" give you? You have more accuracy on the dials with between whole "stops" to fine tune to exact exposure. The triangles indicate which way to turn dials - speed or aperture. Thanks, I appreciate what they are for, but don't see why they are visible in manual with auto iso. What I mean is that if I choose f2 125th sec with auto iso on, I'd expect it to try to use that setting at the lowest achievable iso. So ideally 160 and if not enough light, it would increase iso until it hit my max. I'd understand a warning if it needed above max, but don't understand why I get the triangles when it can achieve that setting at an iso below my max. By definition that is a proper exposure, so doesn't need the triangles. I've done a non scientific test this evening and think that when using auto iso, the triangles are somehow linked to base iso. Basically if I followed the triangles and adjusted speed to get the dot, it always took the shot at base iso. If I dropped the light in the room to a point that I needed a slower shutter speed or higher iso, the arrows showed up. If I ignored them and took the shot, the result was good, but the iso moved up as expected. Not sure if this is any clearer? Thanks, Steve Sent from my iPad using Tapatalk Link to post Share on other sites More sharing options...
jim0266 Posted July 13, 2016 Share #5 Posted July 13, 2016 Steve, in auto iso in manual mode when you see a left or right triangle the camera is trying to say you are outside the base or maximum iso you have set. Left triangle is on you need a wider aperture or slower shutter speed. Right triangle is lit a smaller aperture or faster shutter speed is needed to get back inside the iso parameters you have set. "but don't understand why I get the triangles when it can achieve that setting at an iso below my max." If you were outside on a bright day and had auto iso engaged and were using 125th @ f2 you would need way less than 160 ISO to achieve proper exposure. Your right triangle would be on to alert you in this situation. Link to post Share on other sites More sharing options...
stevebuk Posted July 13, 2016 Author Share #6 Posted July 13, 2016 Thanks Jim, that helps a lot. So my thoughts on a base ISO link seem correct. It seems they are not too clear, because if I am using 125sec, f2 indoor, the light may well indicate I need to reduce shutter speed for the correct exposure. I may choose to ignore this as I may be happy with a higher ISO. But in this case I'm not really sure if my max ISO of 800 will be enough and as such if the exposure I want can be taken correctly. I am correct to assume the camera doesn't notify my of this situation? It seems I have to take the shot to check as I may not need to reduce as the indicator may be talking about base ISO out of range and not max? Hope I've not muddied this further! Link to post Share on other sites More sharing options...
Gregm61 Posted July 13, 2016 Share #7 Posted July 13, 2016 Advertisement (gone after registration) Outside on a bright day at ISO 100, it takes 1/4000 second to get a good exposure at f2, If you leave your manual exposure setting at 1/125 second and f2, the image would be totally blown and one of those triangles will be blinking like crazy to get you to make some change as no auto ISO setting change will fix it. Link to post Share on other sites More sharing options...
jim0266 Posted July 13, 2016 Share #8 Posted July 13, 2016 It might be helpful to think of auto ISO in film terms. The beauty of digital is the ability to change the ISO from shot to shot, where with film we are locked into one ISO for the entire roll of film. Auto ISO goes one more step, unlocking that third variable (ISO) as an equal partner to shutter speed and aperture. Now when you combine manual exposure with auto ISO you are really engaging in another auto exposure mode, but you are controlling the two most important aspects that influence the look of your images, shutter speed and aperture, and letting the camera choose the ISO. Within reason, why do I care what ISO the camera needs to achieve optimal exposure with the shutter speed and aperture I've chosen? Plus, I still have the option to tweak the exposure with the exposure compensation dial as needed. For cameras that do not offer auto ISO (the new M-D for instance or my Canon 6D), you cannot work as quickly in manual mode. You have to stop and change the ISO. I've found manual mode with auto ISO a great option in lighting situations where I know the SS and aperture needed to pull off the photo. During sunny outdoor shooting situations I usually switch back to auto and choose the aperture I want as there is plenty of SS needed to handhold or stop motion. There is more risk of overexposing in this situation. With auto ISO I'm just mindful to keep an eye open for those triangles popping up to warn me I've run out of ISO room. Link to post Share on other sites More sharing options...
eujin Posted July 13, 2016 Share #9 Posted July 13, 2016 Frankly, I find the auto ISO on the M9 a bit frustrating to use. Mine is inconsistent enough with shutter speeds when used with aperture priority that I pretty much select ISO manually these days. In contrast, I always use auto ISO with my Monochrom (also M9 vintage) and it works perfectly there. Link to post Share on other sites More sharing options...
stevebuk Posted July 13, 2016 Author Share #10 Posted July 13, 2016 Thanks all. I still think I've not made myself very clear though! I appreciate the overexposure possibility outside, but indoor, if I choose 125, f2 for instance, and assume that to do so would require an ISO above base but within my max range, I would not expect any exposure warning triangles as the exposure IS achievable at the settings I chose if the camera ups the ISO. But the camera, in this situation suggests I need to increase the exposure. If I do so, it is also a fine exposure but at base ISO. The problem is that if I get the warning, even if it can work by using the ISO within my limit, how would I know if it was not achievable and really no ISO headroom existed? I'd only expect the exposure warning in this case. Does this make more sense or am I missing something? Regards, Steve Link to post Share on other sites More sharing options...
Gregm61 Posted July 13, 2016 Share #11 Posted July 13, 2016 The only thing to be wary about in setting a manual exposure and letting the camera assign the proper ISO indoors is, the camera will assume you are metering a middle luminance whether you are or not, possibly overexposing the entire scene. I find myself either dialing in negative exposure compensation more indoors, or using positive compensation if the scene is brighter or with a lot of white/light colors, or shooting manually and making the adjustment to the exposure myself, with a manually set ISO, to not lift the overall exposure levels indoors more than what looks "right", whatever right is. The camera will always assume it's metering a middle grey in the scene whether it really is or not. Link to post Share on other sites More sharing options...
stevebuk Posted July 14, 2016 Author Share #12 Posted July 14, 2016 Thanks for all the responses, all very valid. However, it still seems the indicators are linked to base ISO and do not always show anything of value. (Sometimes they do, but it would be better if they did nothing when the exposure could be fine as otherwise you are never sure if to trust them or not). Link to post Share on other sites More sharing options...
IWC Doppel Posted July 16, 2016 Share #13 Posted July 16, 2016 I don't know why you don't just use manual adjustment then the triangles will be very useful. It will also allow you to quickly choose how you want to compromise bright and low light conditions. You'll quickly get to appreciate say 160/f4/500th kind of day. You will feel comfortable deciding to hand hold at say 1/15th so you can keep the right side of ISO 640 and so on. It's much more controlled and easier after a little time. At night I know I want to be using f2 or f1.4 if I want to keep the ISO below 800 and you get a feel for the right compromise as you head out, then it's only a tweak on shutter speed and your done for the situation (you also get a quick feel for 1-2 stops so four 2-4 clicks with sun followed by cloud cover). It saves a lot of time, pointing towards the sun and being careful of having sharp black silhouettes in focus as well Link to post Share on other sites More sharing options...
stevebuk Posted July 16, 2016 Author Share #14 Posted July 16, 2016 I don't know why you don't just use manual adjustment then the triangles will be very useful. It will also allow you to quickly choose how you want to compromise bright and low light conditions. You'll quickly get to appreciate say 160/f4/500th kind of day. You will feel comfortable deciding to hand hold at say 1/15th so you can keep the right side of ISO 640 and so on. It's much more controlled and easier after a little time. At night I know I want to be using f2 or f1.4 if I want to keep the ISO below 800 and you get a feel for the right compromise as you head out, then it's only a tweak on shutter speed and your done for the situation (you also get a quick feel for 1-2 stops so four 2-4 clicks with sun followed by cloud cover). It saves a lot of time, pointing towards the sun and being careful of having sharp black silhouettes in focus as well Thanks. That is how I plan to go forward, but just couldn't understand why AUTO-ISO manual behaved as it did. I do prefer to have ISO control myself. Link to post Share on other sites More sharing options...
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