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Sigma DP2 Merrill shots

antara

New member
Still waiting to buy the Dp2M when I can use a site that allows my credit!
I have a pixel peeping question, not a critique, just curious.
With a decent sensor and lens, I can peep to 200% without radical pixelation(still pretty smooth).
I notice this is not the case with the foveon sensor. The little square pixels jump out at you. Is it the sensor or the lack of NR or? Can anyone explain to my sometimes nerdy mind?
I have always assumed when it doesn't pixelate at 200% there is more headroom for editing. True here too?
 

peterb

Member
@Louis..LOVE your early morning captures!

@Antara: I think I know what you're asking but not sure I'll be able to answer it to your satisfaction (and if anyone else far more knowledgeable than myself can answer, please take a shot at this). Are you saying that you see individual pixels "jumping out at you" in an enlarged image produced by a Foveon sensor at 200% and not with conventional sensors?

If that's the case the only thing that I could possibly think of is that since there is no fudge' factor involved with the interpolation of the pixel array of the Foveon sensor (i.e. a computer algorithm intervening to make the best educated guess as to what values a primary color would have in the spaces where no sensor for that primary color is present) my guess is the pixels you are seeing (or perceiving) are more accurately displayed and not 'smeared' (that's the most accurate way I could think of to describe it) as they are in a Bayer generated image. In other words, instead of a mishmash of pixels you typically see from a typical sensor with a Bayer-type arrangement with the very accurate Foveon sensor since you don't have the mishmash since they're all the same (discreet arrays of red, blue and green and not some interpolated Bayer approximation) you start to see the pixels to the point of jumping out at you. (Since there's no distinction with the Foveon sensor you therefore get the accurate read.)

While that is certainly a possibility given the nature of the sensor and how images are processed and printed I'm not sure that would be the case. Because since the Foveon architecture stacks layer upon layer upon layer of silicon sensors one on top of the other so each point accurately measures the primary color component at its individual loci on the sensor (and with no need for an anti-aliasing filter to accommodate the absence of pixels measuring the values of primary colors hitting adjacent loci on a Bayer-type sensor) you're capable of a much sharper image within that space. And when you consider that in a normal Bayer array each pixel does the job of four so to speak (remember it's a massive collection of 4x4 pixel arrays each with one red, one blue and two green pixels) and can then be at least minimally doubled (200% from what you said) thereby making each pixel now doing the job of 16 pixels (and in the case of green ones 32!) the Foveon sensor with its fully mapped out layer of pixels stacked on on top of the other should be capable of taking a 4 x 4 array of pixels alone determining the value of a single primary color (with similar arrays of remaining two quietly working below) and extrapolating THOSE the way you would a Bayer type sensor you should be capable of making enlargements of up to 64x as much (4 x 16). Theoretically at least although in reality there's probably some other intervening factors. Which is why we're all aghast with the images we're seeing from this tiny camera. As evidenced even further by Quentin Bargate's utterly stunning, gorgeous stitched panorama of Cannes Harbor!
 

antara

New member
Thanks, Peter.
Altho some of your explanation is over my head, I think I get the gist of it.
With the original image at 200% you see pixels, but after interpolating up to 20x 30 using bicubic in PS, this is no longer the case.
Makes sense in terms of your explanation. Yes?
 

pophoto

New member
Here is the Pano from the first day testing, I used PTGui Pro for the Stitch (Thank you, pflower for the recommendation), it is so much better than PhotoMerge from Photoshop, no broken lines from the cabling! The full size image is 10651x6499. Just a quick post, now my son is sleeping :)

[/url] PTG_HDR Panorama_Web by PO-MING CHU, on Flickr[/IMG]

Here is the selected 100% detail:


PTG_HDR Panorama_Detail by PO-MING CHU, on Flickr

The detail is insane from the DP2M, it's surely one of the cameras that you have to see with your own eye to believe in, tell anyone it has an APS-C inside, and they will soon lose interest! Now I just need to find more time to shoot with the camera, and yes, PTGui Pro is great and very easy to use, I used PS to straighten the perspective!
 

pophoto

New member
I have a feeling after using DP2M shooting various subject matter, that the camera is really only suitable for shooting any subject matter other than "people." In color, and "very dependent" on the lighting conditions even outdoors, skin tones are hideously inaccurate, and due to the resolving detail the foveon sensor produces, it highly accentuates all imperfections to the surface, almost like localized clarity from LR on skin alone , in particularly middle aged people and older, and less so in children, clarity turned up high! I can only make similar comparisons to shooting people with IR cameras, where people subject matter is less flattering. It is almost to the extreme point, that in color, there is no correcting for this. When converting to B&W, this helps tone down the contrast otherwise seen, and is helped by NOT viewing at 100%.

I have also tried shooting with a Nikon SB 900, triggered with radio transmitters through a soft box, and portrait distant snaps of my 2 year old at ISO 800, to be very useable, where otherwise isn't, but is probably as far as I will go ISO wise, so far only seen through the back of the screen.

I purchased the camera mostly for landscape subject matter, to be more than happy with the resolving detail, exactly what i expected, but was hoping people wouldn't be such an issue, but it is. I'm also not talking about having luck for a few successful people shots, but in a general case!

These are my observations so far, and far from being a rant, but I also wanted to see if others share the same feeling with DP2M and the foveon sensor, and if others had more luck, and can chime in for discussion.

My general opinion of the DP2M so far in one word is incredible.
 

scho

Well-known member
Our sugar maples reached peak color and now they are dropping leaves. Unfortunately, that means I'm going to be busy raking, blowing, and mulching leaves for a few weeks.:(

DP2M stitched images

FULL SIZE


FULL SIZE
 

Quentin_Bargate

Well-known member
hi Po- Ming

I know what you mean but I don't entirely agree. huylss has show the DP2M Can be used very sucessfully with people. I have Done a few people shots with it and it does err on the sie of extreme "realism".

It cuts to the essence of the subject like a scalpel.

Quentin
 

scho

Well-known member
hi Po- Ming

I know what you mean but I don't entirely agree. huylss has show the DP2M Can be used very sucessfully with people. I have Done a few people shots with it and it does err on the sie of extreme "realism".

It cuts to the essence of the subject like a scalpel.

Quentin
Agree. I think that I will recommend the DP2M to my dermatologist who currently just uses a little Canon P&S.:)
 

retow

Member
I thought it renders skin tones quite nicely and accurately. Of course bitingly sharp and depending on ones agenda maybe not the camera to take pictures of the mother in law with:ROTFL:
 
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pophoto

New member
I thought it renders skin tones quite nicely and accurately. Of course bitingly sharp and depending on ones agenda maybe not the camera to take pictures of the mother in law with:ROTFL:
I think this is my point, more usual than not, and if you reread my post, the middle age are at the most disadvantage. I also think that if you regularly shoot photos of your friends, you may soon lose them, than gain their favor :p

It isn't a natural portrait camera, like most DSLRs, at least not on the beauty side of things. I think if a travel photog, were traveling to remote parts of the world capturing the essence of different cultures, say, china, India, Africa, Middle East, capturing the type of journalistic portraiture, it may give you something more, as you may say clinical and different enough. It certainly IS doable, but it just isn't the friendly type by any standards, and while it may be argued, I don't think it renders skin tones well at all. You can certainly favor conditions to shoot better, but it means going out of the way. Again, I will choose my subject carefully :)
 

biglouis

Well-known member
Po-ming

From what I have seen of people shots with the D800 there is a similar problem. The test shots of models published by Nikon show that under their makeup their skin was pitted, full of zits and blackheads and other unsightly blemishes.

Maybe high resolution photography is not suited to people!

LouisB
 

pophoto

New member
LouisB,

This may be very true, although it can be argued that MFD has seen many great portrait shots, and further argued that shots are taken in very controlled conditions, or one that favor it.


I saw the hyluss Bowman photos and like them a lot! I'm not arguing that it cannot be done, but just not a general camera for it. I'm sure when someone comes along disproving everything I said and shoots beautiful people consistently of all ages, I will only respect them all the more! :)


I am still going to shoot people with this camera, until I can find a consistent way to shoot them in better light under more conditions! Although, that's the side of me that finds the camera incredible, and feel it can be bent that way, although I may still fail compared to others! Although right now, I don't think my wife who is 8 months pregnant will allow me to point the camera her way! :p
 

volkerhopf

New member
So, I wondered, what does a DP2 image look like when uprezzed to about 60mp? Is it a pocket medium format camera?

60mp is where the top of the range Hasselblad resides, and the IQ160 from Phase One. Can the DP2M match its performance in resolution terms?. Am I barking mad to even consider this a sensible challenge?

Form your own view. I have uploaded the above hand-held DP2M shot of Clarence house at 200%, roughly equivalent to a 59mp image (9408 x 6272)

Here is the link (below). Warning - *very* large jpeg file at max quality. The image was rezzed up using Photozoom Pro 4, S-Spline Max algorithm, some subsequent minor sharpening and a touch of grain added for realism. Not for a slow bandwith connection. sRGB.

https://dl.dropbox.com/u/9806585/59mp upscale of DP2M image.jpg

It's not perfect, but is it in my opinion very good. No visible halos. This is a massive enlargement, but there is still a lot of detail. In print, I would wager it would be hard to detect it was not from a MF camera. There is some smearing of fine detail, but I decoded with standard NR so I could reduce that by decoding again with NR turned off. In other words, I did not make any particuar effort to minimise NR impact and I had sharpening turned down in Sigma Photo Pro. I have no idea if the end result would have been even better if I had chosen other settings. I just took a punt with this image. Also I perpective corrected the image which will affect pixel level shaprness.

The limits of the sensor resolution can nonetheless be seen.

I am sure I can do better.

Quentin
Thank y ou Quentin for sharing these great pictures.
I will be getting my DP2 next week. The main reason for my purchase was that I wanted a camera small enough to take with me all the time and an image quality that will let me print large prints ( 24x39" and larger ). Since I am not the most patient person I downloaded your unpressed file and did a test print on a medium similar to the old Cibachrome at 40x60". The result was mind boggling !
I am looking forward to printing my own photos.
Cheers, Volker
 

Millsart

New member
I'd say its really a question of if your attempting to flatter the subject, or show the reality of the subject. Isn't so much a camera issue, but a general aesthetics issue.

Make up, digital retouching, skin smoothing etc, is all typical for the course of some portraits, especially female glamor/fashion type photography.

At the same time, some photogs may want to actually showcase and feature every last line on a face, think something along the lines of an old cowboy who's lived a hard life. You want to show off that raw honest appeal of every last wrinkle and scar, as there is a life story written in them.

I remember back in college doing tight portraits with a 4x5 large format, simply for the awesome tonality and resolving power. No make up artist, no retouching, just pure and raw portraits.

DP2M (especially in b/w) is great for this
 

pophoto

New member
I'd say its really a question of if your attempting to flatter the subject, or show the reality of the subject. Isn't so much a camera issue, but a general aesthetics issue.

Make up, digital retouching, skin smoothing etc, is all typical for the course of some portraits, especially female glamor/fashion type photography.

At the same time, some photogs may want to actually showcase and feature every last line on a face, think something along the lines of an old cowboy who's lived a hard life. You want to show off that raw honest appeal of every last wrinkle and scar, as there is a life story written in them.

I remember back in college doing tight portraits with a 4x5 large format, simply for the awesome tonality and resolving power. No make up artist, no retouching, just pure and raw portraits.

DP2M (especially in b/w) is great for this
Which reality? :p

I really wasn't trying to flatter the subject, but in reality it did quite the opposite!
I think to make my posting more clear, if I shot a DSLR with a very sharp lens, say tele end of 85mm, or a macro lens... Well it wasn't doing that sort of honest of showing just every detail, it was more about how it pushed the limits of what you were seeing with your naked eye.

Last weekend, I visited friends, and we went to the park with our 2 year olds. Lets just say the pronounced skin detail, isn't what I would say I was even picking up with my eyes.

From my original post, I made a comparison about LR clarity being cranked up, and also shooting with an IR camera, so servere that while the blemishes maybe accurate as to facial location, the contrast and intensity was not!

Unfortunately I won't be posting photos of my friends to demonstrate this point, but I am sure others who own this camera, and shoot enough people, may understand the point I am trying to stress when they come across it. It certainly won't happen all the time, but all twenty or so frames, the adults, including myself looked very bad, while the kids were fine, if the tonality were inaccurate according to me.

Very raw, might describe what I was seeing! :)

The camera might even be sharper than my eyes LOL!
 

Millsart

New member
Its no different than how you set up your studio lighting, and the type of modifiers you use. The way I'd light a childs portrait is different than a 40 some year old female and different, than as previously mentioned, an old weathered cowboy. Hard light, soft light, etc. They are tools, just as the DP2M is a tool.

Would I use it for snapshots etc ? No, mainly because its simply a horrible camera for that type of work, IQ issues aside, and I've got plenty of other cameras that are better suited for casual shooting.

DP2M was purchased as a specific landscape tool really. I'm not going to be taking images of family/friends with it, any more than I would be pulling out the 4x5 Toyo field camera and taking snapshots of kids friends in the park.

However, if the right situations arouse, I wouldn't hesitant to make use of it. Perhaps if a tattoo artist wanted to showcase their work. The fine tonality of the X3 sensor could be a useful tool for this.
 

Rich M

Member
Which reality? :p

I really wasn't trying to flatter the subject, but in reality it did quite the opposite! Very raw, might describe what I was seeing! :)

The camera might even be sharper than my eyes LOL!
Po-Ming........I agree with everything you have said. I wouldn't go around within my group of friends using this as snapshot camera......but in general that same group has become quite camera shy, regardless of type. :ROTFL:

I am still liking/using my DP1M more than the DP2M. Here is a quick shot with what I would loosely call an "environmental" portrait.



With this type of shot, I would take this level of detail hands down over another (more flattering) combination of camera and lens.



Uuummmm.....BTW, I won't be using this for any self portraits :D

R
 
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