18 replies to this topic

[Nikonite]

   First Baptist here in Orlando puts on an awesome Christmas show called the singing Christmas trees. I took my camera this year to practice up on my night shots. I was pleased with my results. The best results were obtained in aperture priority mode, but when I look at the details ISO is blank for every aperture priority shot? For other shots not taken in aperture priority ISO has a value. Anybody know why that is? 

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[Kenafein]

Looks like quite the production.  

[etphoto]

Need more information, like maybe what camera you are using.

[Nikonite]

Ok, A D7100 with the Nikkor 35 mm prime lens.

[etphoto]

One more question, what aperture and ISO did you choose?

[Nikonite]

Since it was about dark I completely opened the aperture up to 1.8 (max for the lens). ISO was chosen by the camera. Hence the reason I'd like to know what it was, but as mentioned on all the aperture priority shots the ISO field is blank.

[Jerry_]

@Nikonite, would you mind uploading one of those captures as an exact copy of what the file was that you copied from the camera, as a shared file in Dropbox (or similar).

The reason why I am asking is that I have occasionally seen (mostly after using photo editing tools, not sure if it also applies for information saved in the camera) information stored under different metatags, so I would like to check all the metatags contained in the file.

[Nikonite]

The pictures in this post are the jpeg files straight out of the camera. Zero post editing. Interesting though you gave me a thought. I opened the jpg and nef files under DXO and the ISO values are there. So it seems only Windows 10 is having a hard time displaying the ISO values.

[Merco_61]

The problem is that the forum software strips EXIF from attachments. It would be interesting to see what strangeness has happened in-camera.

[Nikonite]

That may be, but what I'm referring to is the jpegs straight out of the camera when taken in Aperture mode. For whatever reason the ISO field is blank? Under photo apps I can see the ISO data, but not under the Windows 10 properties?

[Merco_61]

It would be interesting to see if the D7100 writes auto-ISO in another format than the usual

 

<exif:ISOSpeedRatings>

            <rdf:Seq>

               <rdf:li>value</rdf:li>

            </rdf:Seq>

         </exif:ISOSpeedRatings>

 

format. As the ISO is stripped on the photos in this thread, we can't help you understand why.

[Jerry_]

In the EXIF metadata there is one tag called ISOSpeedRatings
This is the field where the camera will (normally) store the value for the ISO settings used.

I don't know how the camera stores the fact that it was in AutoISO mode, which is complementary to the ISO setting used.

As other programs than the Windows 10 viewer can return the ISO value, I suppose it is in the good place. Which would leave the no-show to the viewer, based eventually on other settings in the EXIF data.

As Peter confirmed, in order to possibly identify the basic reason for this, one would need to have two of the captures (one taken with, and another one without, AutoISO), without the EXIF having been stripped.

On internet you can find different free and commercial software which allows to view the full EXIF data (some software will only show selected tags, or eventually have a conditional show/no-show)

[etphoto]

I propose an experiment.  Set your aperture at F8, go outside and shoot a picture.  Check the info to see if the ISO is recording.  I wonder because of the weird lighting conditions for some reason the ISO wasn't recorded. 

[Nikonite]

The ISO was recorded. Windows 10 just isn't displaying it under properties? Here are 2 screen shots from the same picture. In the DXO screen shot the ISO is recorded as 12k. Interesting that the camera chose 12k. Just what I wanted to know.

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[etphoto]

Mystery solved.

[Nikonite]

Except for the part where Windows does not list an ISO value for Aperture priority pictures?

[etphoto]

That's a windows issue, not a camera one.

[Merco_61]

Is it the aperture priority or the 5-digit ISO that makes the Windows viewer lose the plot?

[Nikonite]

I have other aperture priority pictures from that evening that are not 5 figure ISOs and the ISO value still does not show under Windows10. I have to open the picture with a photo app to see the ISO. That leans toward something about the aperture priority mode that isn't working well and playing with Windows. However, I always say when in doubt blame Microsoft!