Detail and resolution question

Note: This question is not to start a digital/film debate. I posted it on the earth,sea & sky forum but Lon Overacker thought I would get more answers from this forum.

For the past year and half I have been shooting digital. I am using a Canon EOS 1Ds Mark II — 16.7 mg pixel. I mainly shoot landscape photography and my question concerns the quality, sharpeness, resolution, detail, etc.

The following link will take you to a cropped portion of the above image at 100% resolution. My full size image at 300 dpi. is 11.093" high X 16.64" wide. The photo was shot with a Canon 24-105mm f/4 L lens at 105mm; f/8 at 1/6 sec. I was standing about 70 feet from the tree stand. There was no wind and the light is just as the sun was coming up behind me. The tree trunks in the full image are sharp and in certain leaves I can see vein detail. However, for the most part the leaves look as if they have no individual detail—they appear to be just mushed together.

http://www.pinehillgraphics.com/aspen/AspenCrop.jpg

If I were to have shot this with 4X5 and velvia 50 asa would I see more definition, resolution and sharpeness?

For most of my landscape shooting I must keep in mind that it could be used for offset printing (book covers, etc.) so I constantly think in terms of 300 dpi for printing and not just making large photo prints.

Any help and comments would be appreciated. I am not trying to get into a digital/film debate.

Thanks, Fred

It's difficult to tell without seeing a histogram but what might be happening is oversaturation. Just like highlights can become blown out and devoid of detail so can colours. If a colour becomes clipped due to oversaturation you'll lose detail.

Fred - First, I think resolution (probably the same as "defintion" in this case?) is probably limited by your sensor in this case, assuming this is at base ISO, and that the lens is good at 105 mm (which is very likely). As for sharpness, that may be affected by having your lens at max. zoom, and could be leading to a loss of resolution if things are really not sharp. I don't know enough about that lens though - but primes of similar quality are almost always sharper.

The other major factor affecting sharpness could be your post processing. Was this shot RAW? Are you very proficient at RAW processing? If it's JPG or TIFF, the in camera settings can make a big difference. You could be losing detail there as well. Sharpness, assuming the detail is captured, can be improved in post-processing as well.

In general terms, I've seen 35mm film compared to anywhere from 8 to 20 megapixels. The variation usually depends on the particular shot, and shooting conditions (lens used, ISO, exposure time, etc.) and whether you're talking physics, or detectable differences in prints.

Now you've asked about 4x5, which of course is much larger than 35mm....I'd say that 4x5 (having never shot film) is likely to be capable of resolving a lot more detail than your 1DsMKII. This would, like with your setup, somewhat depend on the lens, but I think medium format lenses are typically not the limiting factor. If you assume the same field of view, then the 4x5 captures this image in almost double the area of 35mm (and almost double the area of your sensor) and should be able to resolve a lot more than your camera.

Hope that wasn't too rambling - thinking through it myself. I'd guess any of the larger format film shooters here could probably give you simpler confirmation.

I've looked at the 100% file and I think that the issue is lack of microcontrast. This can be improved by "sharpening" the image. If you have Photoshop, I would recommend the Smart Sharpen filter (start with Amount of 75% and Radius of 1.0)

It's difficult to tell without seeing a histogram but what might be happening is oversaturation. Just like highlights can become blown out and devoid of detail so can colours. If a colour becomes clipped due to oversaturation you'll lose detail.

Good point.
The green channel is clipped on the right and the blue channel is clipped on the left.
The RGB histogram shows clipping on both ends.

David also raises good points about whether this was captured in RAW and the fact that almost all digital images need to be sharpened in order to compensate for softening due to the anti-alias (or low pass) filter.
This old (but still good) short essay from Microsoft (..of all people!) explains a bit more about that.

Did you use a tripod and mirror lockup here? Lots of factors to judge before a decent diagnosis is attempted.

I think this is fairly common for the subject matter. I've certainly run across this problem in the past. The direct warm light of sunrise (or set) on yellow aspen leaves is a deadly combination for many sensors. Try cooling off your white balance significantly, to see if any details return (just for the sake of experimenting).

Other than that, I don't see anything wrong with the resolution of your 100% crop - especially since you've shown the very edge (where details usually fall off anyway) and the weakest focal length of this lens was used. This is probably the best you'll get, under the circumstances.

And yeah, you'd certainly see more detail in a 4x5 shot.

Fred,

First off, it has also been my experience that the digital sensors I've used and seen really struggle with yellows and red, so your experience is not uncommon.

Yes you would see more detail in a 4X5 shot with an equivalent focal length (roughly 300mm). One sheet of 4X5 films is roughly like shooting 12 frames of 35mm. Velvia might not be the best film for these yellow leaves though. Based on my recent tests of a wide variety of films I would probably choose E100VS, E100G or E100GX for this application, depending on the level of saturation and warmth you wanted. Kodak slide films seem to produce much cleaner yellows, oranges and blues than Fuji. Fuji slide films (except for Astia) seem to be much stronger in magenta and green tones.

You would also find that well scanned MF film would also produce more detail than your DSLR. This may not be true on a consumer flatbed, but on a dedicated film scanner, professional flatbed or drum scanner, even 645 should come out well ahead of the 35mm DSLR. Even 35mm slides scanned very well will match the resolution of 1DS2, they just won't be grain free. Film might not lose detail in the yellows the way digital will.

A view camera is very different in use if you've come from an SLR. Its slow to setup, and even changing lenses requires a fair bit of time. There are medium format SLRs that might work much better for you if you like to compose and shoot quickly.

To back up the 4X5 claim here is an example.

This the entire image. It was shot on Astia with my Fuji 210 -NW.

Here is a 100% crop from my Epson 4990 at 2400ppi. There is still more information in the film, but my scanner cannot produce resolution beyond this point.

The leaves separate fairly well I think considering the scale of the image.

I don't really think (m)any people have trouble believing that 4x5 film would be superior to a cropped sensor DSLR, Mel. At least in equal sized prints. At the image plane it might be a different issue but it's a print that matters.

I think your 4990 should be able to do better than that too. Is that scan sharpened?

I thought it would be helpful for a couple reasons. Fred was asking about separation in the leaves and I brought this up to demonstrate that film may keep the detail in yellows and oranges where digital falls apart. I'm only trying to show that the film maintained separation in the yellows even on a fine scale. I would have chosen 35mm if I had a particularly good example.

As far as my 4990 goes, I'm sure it could do better, but my holders have developed some warping and I've been having some trouble with that. I am convinced that 2400ppi is right about the top real resolution of this scanner though. This has been sharpened. I'm at a cross roads between buying a drum scanner and just keeping this 4990 and getting a betterscanning holder. I don't print large often, so I'm not sure a drum scanner is really a good investment.

This has been a lot of help to me. I didn't realize that there were problems with yellows and oranges with digital cameras. I only shoot in raw so I can perhaps get more out of the photo by going back to the original and starting over. I also looked at the histogram and there is indeed clipping off of both ends which dosen't help. I read through the article mentioned above on sharpening and will work on that also.

Thanks everyone for your input. It is good to know that one only has to put out the question and there is help to be had.
Fred

There aren't inherent problems with yellows and oranges in digital cameras. RAW is a good choice and a bit of tweaking of the RAW file in ACR is very likely to make a difference for you. Have a look at the Recovery slider, the Curve adjustment and then the individual colour sliders as a start and see if something more pleasing to you doesn't result.

Make certain that you turn on the RGB histogram feature on the camera. This will allow you to verify that you are not blowing out certain colors. I learned the hard way years ago by using the luminosity histogram. Even though it may show the scene within the range you can still overexpose certain color causing this problem. Autumn color is a real problem if you do not use the RGB histogram.

BTW Fred, I'm a book publisher and I've done many projects with a mixture of my 4x5's and digital images and to this day no one has been able to distinguish the different formats. At the size of books and calendars and if you know how to process and sharpen the files you will see no difference either.