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Sigma DP2 Merrill shots

foveon

Member
Florin, wellcome, your shots arent overexposed but you shot at the wrong time, when the sun was very high. Better is to shoot when the sun is lower, contrasts are not that harsh, shadows are more visible to bring 3D look and colors are more saturated.
 

foveon

Member
My standard settings on the DP2m are: ISO: 200, colors: ntr, contrast: -0.2, saturation: +0.2,
there has been some discussion about, a lot of people see ISO 200 as the native ISO with the widest dynamic range
Have fun and be patient with your Sigma baby, its worth the effort.
 

foveon

Member
Florin, caused by your Thanks, some more words:
This forum is the place to find pics from some excellent fotographers, so dont be frustrated if you compare to your work but try to see what makes their pics that good.
Beside composition its all about light, as basic rule: you cannot force a good picture (outside the studio ), you have to be patient and wait for the right light for the place you want to shoot. I am sure here are outstanding landscape pics where the shooter has been 10 or more times to look for the light, "good" light not only depends on the position of the sun but also on haze on so on.
 

Florin75

New member
Thank you again for your advice!
You are true, that day was far from being a good day for landscapes, not even at sunrise or sunset. I hope that in two weeks time mother nature will show us more colors and good light, as the vegetation will turn to yellow or red and fog will be all over.
I know photography is about light, composition and patience. It is a real pleasure for me to look at the images shot by the much more experienced photographers on this forum, and, as I said, even if I am not an artist at all, I hope that some day I will take a shot close to what I am seeing here.




Florin, caused by your Thanks, some more words:
This forum is the place to find pics from some excellent fotographers, so dont be frustrated if you compare to your work but try to see what makes their pics that good.
Beside composition its all about light, as basic rule: you cannot force a good picture (outside the studio ), you have to be patient and wait for the right light for the place you want to shoot. I am sure here are outstanding landscape pics where the shooter has been 10 or more times to look for the light, "good" light not only depends on the position of the sun but also on haze on so on.
 

foveon

Member
to me it seems that composition is not a big issue for you and for the light you just have to wait;
I dont know how far you are away from the places you showed us, good is to choose a place where you can go often at different times, I have here around some places where I go daily or daily twico to look for good light and a miracle.^^
 

Stoneage

Member
Just one word about ISO 200: The dynamic range is not higher than ISO 100, it just gives you 1 stop more highlight recovery at the expense of cleaner shadows. The Merrill sensor is ISO-less, so it's all about the right exposure. ISO 200 and ISO 100 -1EV exposure correction gives you the same RAW file (although SPP handles different ISO with different amount of noise reduction)
 

foveon

Member
dont get the point, "ISO 200 and ISO 100 -1EV exposure correction gives you the same RAW file" and "it just gives you 1 stop more highlight recovery at the expense of cleaner shadows", so is it the same file or not?^^
 

Stoneage

Member
dont get the point, "ISO 200 and ISO 100 -1EV exposure correction gives you the same RAW file" and "it just gives you 1 stop more highlight recovery at the expense of cleaner shadows", so is it the same file or not?^^
If you under expose the ISO 100 shot by 1 stop, then it is the same file like ISO 200 without exposure correction. (it's the same shutter speed)
If you don't under expose the ISO 100 shot, then the camera exposes longer (twice as long) so highlights clip earlier but you get cleaner shadows.
 

foveon

Member
what are you talking about under exposure? I said ISO 200 gives more dynamic range and I dont set exposure by compensation but manual all the time^^
 

Stoneage

Member
what are you talking about under exposure? I said ISO 200 gives more dynamic range and I dont set exposure by compensation but manual all the time^^
Yes and i said this is not the case because dynamic range is more than just highlight recovery. It's also about shadow recovery.
 

xpatUSA

Member
The Merrill sensor is ISO-less,

I have never heard that. What do you mean?

Tony
Allow me:

Unlike the majority of Bayer cameras, the majority of Sigma Cameras do not have a variable gain amplifier (VGA) in front of each analog to digital converter (ADC). The exceptions are the SD15, the DP1x, DP2x and the Quattro, all of which have been said to "lack headroom".

So, with a Merrill and talking raw, the camera ISO setting is simply written into the X3F meta-data and SPP does the "amplification" that conventionally would have been done in-camera. That is to say that, for a given exposure, the raw data itself is not affected by the ISO setting, hence "ISO-less".

And that is why, as said in earlier posts, there is absolutely no difference in the raw data between shooting at 200 ISO, 0EV or at 100 ISO, -1EV or even 400 ISO, +1EV for that matter. In SPP, appropriate movement of the EC slider will give 3 identically bright images.

I myself shoot at 160 ISO with my SD1M because that is about the closest it gets to the official ISO "saturation based" method of determining the exposure index for a digital camera.

Ted
 

Stoneage

Member
The Merrill sensor is ISO-less,

I have never heard that. What do you mean?

Tony
It means that "ISO" is just a "tag" in the RAW file. ISO 800 in reality is the same like ISO 100 under exposed by 3 stops. If you open it in RAW Digger, you will see a very dark/"under exposed" photo.
 

xpatUSA

Member
I said ISO 200 gives more dynamic range and I don't set exposure by compensation but manual all the time^^
The trouble here is that "dynamic range" has several definitions. Therefore the statement might or might not be correct. For example, noise-based and taking the range as being between the brightest and darkest parts of an image, we could say that dark noise is some number, maybe 8, which is always there no matter what the exposure.

Now we meter some scene at ISO 100 and shoot at +/- 0 on the meter. Let's say the sensor outputs 4000 out of a possible 4095.

The captured dynamic range is log2(4000/8) = 9EV. The raw headroom is a count of 95.

Now we meter same scene at ISO 200 and shoot again at +/- 0 on the meter. The sensor will output 2000 out of a possible 4095.

The captured dynamic range is log2(2000/8) = 8EV. The raw headroom is a count of 2095.

SPP knows you shot at ISO 200, so it multiplies the sensor data by two: the image dynamic range becomes log2(4000/16) which still equals 8EV.

Therefore, by that definition, ISO 200 gives less dynamic range than ISO 100, not more . . .

Ted
 

Florin75

New member
I return with a question: what WB settings do you guys usually use? I use mostly Auto WB but sometimes I like more Sunlight on the camera display, only to return to auto when I view the files on my laptop.
I have one more camera, an Olympus E-450, which lets me choose the WB in Kelvin, most of the time I set it to 5800K-6400K.
With Sigma I am stucked with the preset WB, no fine tunning, not even in SPP.

I hope you will not find my question stupid, I am only begining to experiment with this camera and RAW editing. Olympus jpeg straight from the camera is perfectly usable.

first image with Auto WB, second with Sunlight.
 

Attachments

Does the Sigma Raw file alter when the WB in the camera is changed?

I ask because my understanding has been that non Sigma RAWs - such as those from an Oly E-M5 are not altered. It is only the jpg that changes. There may be RAW conversion software that reads the WB info in the EXIF - but that is not the same as the RAW itself changing.

Tony
 

Stoneage

Member
Does the Sigma Raw file alter when the WB in the camera is changed?
No, it's the same like with Bayer Cameras. You can change the WB non destructive in SPP later to your taste.
But it's always a good idea to make a manual WB on the field as this is not possible to achieve on the computer later.
 
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