The GetDPI Photography Forum

Great to see you here. Join our insightful photographic forum today and start tapping into a huge wealth of photographic knowledge. Completing our simple registration process will allow you to gain access to exclusive content, add your own topics and posts, share your work and connect with other members through your own private inbox! And don’t forget to say hi!

Sinar e54LV 'mother of all samples' thread :)

Graham Mitchell

New member
Someone requested this via LL but I may as well share it with everyone here.

What was requested was full resolution samples at various ISOs so I went out and took a very boring photo with no artistic merit whatsoever ;) What is does have is lots of detail, dynamic range and colour.

I took the same shot at all ISOs, changing only the shutter speed and ISO setting.

Then I pulled all the files into Photoshop and layered them on top of each other, with the layer names showing you which layer is which ISO setting. You can therefore zoom in and flick between layers to see the difference up close.

These files are UNSHARPENED and there is NO NOISE REDUCTION.

The member who contacted me offline wanted to do some test prints, so you are all hereby permitted to download, print, or do anything else to this image.

The file is a 511 MB Photoshop file, so I had to split it into 6 smaller pieces in order to host it. These are in the form of a ZIP archive.

http://www.mediafire.com/download.php?iz5uujlny1f
http://www.mediafire.com/download.php?43fc9tmomzd
http://www.mediafire.com/download.php?ygdmnmddewq
http://www.mediafire.com/download.php?jgdd2q2jgl4
http://www.mediafire.com/download.php?qcd0t2zdunl
http://www.mediafire.com/download.php?fvzw5hlylcx






Let me know how you go!
 

Graham Mitchell

New member
Ok, a Mac user is reporting difficulties offline, so here is a guide to restoring the file.

PC users: use Winzip, for example. Free trial version will work. This was utility used to create the plit archive.

Mac (Intel) users: Intel Mac users with Parallels can also run Winzip, or see Mac PPC solution

Mac (PPC) users:

1. Change all the .z01, .z02, etc. file extensions to .001, .002, etc.

2. Change the file extension of the .zip file to .00X (X= the last numeric file extension from the .001, .002, etc. files + 1). In this example, the zip file extension will be changed to .006

3. Join all segments with "MacHacha". (Drag the .001 file onto the MacHacha icon)

Download here: http://tinyurl.com/yk6vsu

4. Change the name of the file produced by "MacHacha" by adding the extension .zip .

5. Unzip the this new zip file with "The Unarchiver". (Drag the zip file you just renamed onto the Unarchiver icon).
Download here: http://wakaba.c3.cx/s/apps/unarchiver.html

I just tested this solution and it works.

If anyone knows an easier Mac OSX solution to restoring a file from a split zip archive, please share! (Next time I will use split RAR instead of ZIP - there is a much easier solution for Mac users).
 
Last edited:

EH21

Member
Graham,
Looks like you went to a lot of work here, but why not just offer the .dng files? Actually all I care about is the ISO 400 RAW file.
Eric
 

Graham Mitchell

New member
Graham,
Looks like you went to a lot of work here, but why not just offer the .dng files? Actually all I care about is the ISO 400 RAW file.
Eric
Then different users could see different things depending on their raw processor, workflow, individual colour balance, etc. I wanted to know everyone was seeing the same thing, without NR or sharpening, and it is very handy to have the results in layers. It is the only meaningful way for people to then exchange opinions.
 

BJNY

Member
"A" for effort,
but why are you splitting the archive file, then to be re-assembled,
when the separate downloads can JUST be the individual 50, 100, 200, & 400 ISO TIF layers?
 

Graham Mitchell

New member
"A" for effort,
but why are you splitting the archive file, then to be re-assembled,
when the separate downloads can JUST be the individual 50, 100, 200, & 400 ISO TIF layers?
The host's file size limit is 100MB which is not enough for a single TIFF. I would have had to split every TIFF file into two.
 

Guy Mancuso

Administrator, Instructor
Going to in just a few minutes trying to get everyone out of the house. There always interrupting me. LOL
 

EH21

Member
Then different users could see different things depending on their raw processor, workflow, individual colour balance, etc. I wanted to know everyone was seeing the same thing, without NR or sharpening, and it is very handy to have the results in layers. It is the only meaningful way for people to then exchange opinions.
Okay understand your thoughts, but yes all the reasons you listed are exactly the reasons why a RAW sample would be valuable to me. I could then try converting it with my own preferences, apply my own curves, test noise, etc. A file that someone else has handled does not teach me as much about the how the camera back performs.

For example I did not get much feeling for the ISO 800 sample Thierry posted until I tried to lift shadows and adjust exposure levels with the RAW he provided on my own computer.

I know how it is though. When ever I try to share/help on the forums there always is someone that thinks I should do it another way or wants something else. Few people say thanks - so thanks Graham for sharing.
Eric
 

Greg Seitz

New member
Hi Graham,

Appreciate you posting the DNG files. The amount of detail looks great. I have a couple of questions regarding the files if you don't mind.

From looking at the files it looks like the back exposes at the base ISO of 50 and the other ISOs are achieved by pushing the exposure in post. Is this true or am I missing something?

Also, just curious about the shutter speeds recorded. As you changed ISOs the shutter speed did not change as I would have expected. It seems to be related to 1 of 3 possibilities - the light changed (doesn't seem to be the case as far as I can tell), the back is not reporting the right shutter speed, or the aperture was changed instead. I'm guessing the aperture changed but just curious if that was the case?

Thanks,

Greg
 

Graham Mitchell

New member
From looking at the files it looks like the back exposes at the base ISO of 50 and the other ISOs are achieved by pushing the exposure in post. Is this true or am I missing something?
That isn't true. Why did you make this assumption? For example, you can overexpose at ISO 400 on settings which would underexpose at ISO 50.

Also, just curious about the shutter speeds recorded.
Afaik, the shutter speeds are not recorded in teh first place because I am using a 6008AF which has no digital interface at all. The shutter speeds were 1/1000 for iso 400, 1/500 for iso 200, and so on. The aperture was fixed so that the file differences would be due only to exposure, not lens performance.
 

Greg Seitz

New member
That isn't true. Why did you make this assumption? For example, you can overexpose at ISO 400 on settings which would underexpose at ISO 50.
I made the assumption based on what I'm seeing in the files. The ISO 400 shot when opened in a raw converter with no exposure compensation is far darker than the ISO 50 shot. It's not till you push it by 3 stops in the converter does the histogram match. I can achieve the same thing if I simulate ISO on my D3 by underexposing at ISO 200 by 3 stops and pushing by 3 in the converter I will get the equivalent of ISO 1600. The "real" ISO 1600 shot would be somewhat better since the ISO is done via analogue amplification and when opened does not appear underexposed as the simulated one would. So I'm just wondering why the Sinar files behave this way...



Afaik, the shutter speeds are not recorded in teh first place because I am using a 6008AF which has no digital interface at all. The shutter speeds were 1/1000 for iso 400, 1/500 for iso 200, and so on. The aperture was fixed so that the file differences would be due only to exposure, not lens performance.
That's strange, the files show shutter speeds between 1/17 and 1/25 in the meta data.
 

Graham Mitchell

New member
I made the assumption based on what I'm seeing in the files. The ISO 400 shot when opened in a raw converter with no exposure compensation is far darker than the ISO 50 shot.
I used Brumbaer to create the DNGs and I think it does funny things. One of the reasons I posted the Photoshop layers first was to avoid all this confusion (which I knew would happen). It is the results that matter. Please look at the Photoshop document to compare properly processed results across the ISO range.
 
Last edited:
Top