Film vs Digital - Dynamic Range

[rishij]

Mauro -- narrower depth of field... I understand that full-frames have narrower depth of field at equivalent apertures (I think), but at f/8 -- do you really think it'd make that much difference?

 

Reason I'm particularly skeptical is because in my own subjective tests, I just don't see my film images appearing sharper than a 12MP Canon 5D. Which is why I find the results from the images above much more on par with my experience, but the results from your '26MP' thread unbelievable. Although I'd love to believe that '26MP' thread because I still shoot & love film :)

 

Rishi

[vijay_nebhrajani]

Just a quick word about sharpness, Rishi - there is a difference (and I am sure you know this) between sharpness and resolution. Imagine a square wave - sharpness has to do with the shape of the edges - how quickly the wave goes from one value to the other. A quick transition translates to higher sharpness. Resolution is about how many low-high transitions you can fit per unit length. Digital almost always appears to have higher sharpness because pixels already have hard edges, allowing sharp transitions.

 

That said, the Ektar shots actually seem too soft - maybe they were not exactly in focus as Mauro says. Also, smaller sensors have greater depth of field and Mauro used strobes measured with a hand held light meter. This probably means that he set both cameras to the same aperture resulting in greater DoF with the digital.

[mauro_franic]

Rishi, yes at f8 and probably a just couple yards from the subject, DoF to evaluate very small detail (at the resolution limit) is too narrow. Especially when all the subjects are that close and not in an exact line.

 

I don't know how to pull the exact focusing distance out of the RAW file but maybe you can.

 

This is shot with the exact same equipment, lenses, film, etc as the dR test but paying attention to the focusing and DoF:

 

Noticed TMX outresolves the scanner. TMX outresolves Ektar. Ektar outresolves the 40D. And Velvia is pending:

 

\http://shutterclick.smugmug.com/gallery/6616619_YJEwK#421902416_ibL4V-O-LB

 

TMAX next to 40D at 200%:

http://shutterclick.smugmug.com/gallery/6560295_hraSq#417849621_RBnJg-O-LB

 

--------

 

I'D RATHER NOT TAKE THE DR DISCUSSION TO DETAIL. FIRST RESOLUTION IS A LOT EASIER TO TEST THAN THIS DR EXERCISE (getting the dummies similarly spaced and one stop apart is not easy), SECOND RESOLUTION OF ALL 100 ISO FILMS I USED IN TESTS OUTRESOLVED THE 40D CLEARLY AND BY A LARGE MARGIN.

[mauro_franic]

Also if you want to use this test for resolution I'd have to rescan without ICE, etc, etc.

[rishij]

Vijay! Good to see you again :)

 

Yes, good point, I understand that about digital -- that point ties in with what I mentioned about the inherent 'lack of local contrast' in film, yes? Although, arguably that's better with positive film due to its exponential response to light.

 

Anyway, Vijay, Mauro, or anyone else -- really? Even at f/8 you'd expect that much softness from lack of depth of field?

 

Rishi

[rishij]

Oh ok Mauro just posted before your response.

 

And ICE does not affect sharpness at 'Normal' (NikonScan) or 'Light' (Vuescan)!!!

 

:)

 

Rishi

[rishij]

Oh yes I did see that post. Bicubic upscaling would help your 40D but wouldn't get any more resolution off the charts.

 

Can't wait for the Velvia 50 results, as that is what I shoot :)

[mauro_franic]

Should get them tomorrow. I'm sure Velvia 50 will outresolve the Coolscan (since I saw that already in my 6x7 test) but it'd be nice how it compares side by side to Ektar.

[mauro_franic]

Rishi, I hate keep correcting. I didn't think ICE normal made a difference until not long ago but as usual I test everything myself:

 

http://shutterclick.smugmug.com/gallery/6616619_YJEwK#425687124_i7c3H-O-LB

[bernardwest]

Rishi... couple of points:

 

As Vijay said the 40D will have greater DOF for the same f-stop and field of view than the 35mm.

 

Did you have sharpening turned off in lightroom?

 

And for both Vijay and Rishi.... remember this isn't fully a film vs digital comparison, as the film has been scanned.

It is really figital vs digital....;) ie. the sharpness due to square pixels should be the same between the two.

 

Another general point to make (this includes you Mauro), is the raw conversion factor. As you can see from my

couple of examples, the choice of raw converter and the settings can affect both dynamic range and detail. In your

original images Mauro it seems you have used dpp settings of +2 contrast and saturation, and a picture style that

may be not optimal (I can't remember what the setting actually was). As far as I am concerned, DPP is basically

useless for these types of comparisons, as it can't present you the more-or-less untouched raw data. It is doing it's

own things behind the scenes, which some marketer at Canon deems is good for you. To improve on these tests in

the future, you should use dcraw (or Lightroom/ACR at the very least), and shoot something that will give you a

better determination of USABLE dynamic range.

 

By the way, you won't get anymore highlight detail than what you see on my dcraw conversion. This conversion

includes ALL the data coming off the sensor (minus of course the noise below the black point clipping point).

[mauro_franic]

I had no clue how good/bad DPP was at this - that is why I posted the raw for people to take a stab at it.

 

In DPP: Minimizing contrast and plus -2 exposure adjustment gave me a good idea that at least 3-4 stops had blown areas.

 

WITH THIS TEST - and everyone's collaboration; we all got a very quantifiable idea on the D-range and clipping thresholds of the 40D vs Ektar.

 

I'd give the 40D 8-9 stops vs at 14 stops for Ektar. I was surprised how well Ektar did considering how contrasty and saturated it is. I was also positively impressed on how well Ektar did in the shadows.

[Dave Luttmann]

If only I could get my hands on some Ektar. I've only worked on scans from other people. Shops in the US wanted to charge $44 in shipping for 5 rolls of film....yes, I call that gouging! For some reason, Kodak hasn't rolled it out here in Canada yet.

[mauro_franic]

I order it from Amazon. I can send you a few rolls. Email me your postal address.

[rishij]

Wait, & I forgot: Bernie!! Good to see you again :) I feel like we've all bonded on that last thread.

 

Mauro -- OK, visually, without resolution test charts, no normal human being could see that difference brought on by ICE Normal :) But, yes, I do see a difference... a bit less is resolved with ICE on, but, on the other hand, surprisingly it seems that there's a tiny increase in contrast or sharpness. Funny enough, I thought I saw this on my own comparisons of ICE on/off with regular images... but I put it out of my mind b/c I couldn't rationalize ICE actually increasing sharpness.

 

Also, as I mentioned earlier (I think), the extra stops on Ektar is really not surprising. Not only do the layers get blacker as exposure increases, making more exposure harder -- but also the sensitivity specks on the surface of the grain start accumulating electrons, thereby repelling more electrons being knocked off of bromide ions by photon absorption, making the process of collecting electrons to reduce silver ions less and less efficient. Which amounts to harder and harder exposure as exposure continues.

 

Anyway, I still find ICE Normal quite acceptable.

 

Cheers,

Rishi

[mauro_franic]

But we are not normal. we are perfectionists... ha ha

 

I usually prefer ICE fine because it has a smoothing effect without sacrificing much detail.

 

Please post your results of your ICE test. I am very interested in contrasting results.

 

This ICE exercise should answer your question on detail since we are moving in-between 3600-3900 lines per picture height for 35mm with the Coolscan and the 40D captures barely over 2000.

 

 

It is the Holiday spirit rubbing off and making us bond...

[vijay_nebhrajani]

Rishi: Wait, & I forgot: Bernie!! Good to see you again :) I feel like we've all bonded on that last thread.

 

Stockholm syndrome?

 

Kidding, buddy, kidding :-)))

[finny99]

How about this for dynamic range? Cheap Canon Rebel G with 50mm 1.4.HP5 No manipulation in PS.

Back using film and loving every minute of it !!!! " While my 20D gently weeps "<div></div>

[mauro_franic]

That sounds good to me (that used to be my favorite combo too). Also Greg, order yourself a brand new Canon Elan 7ne before they go out of production - only $350 at BH with metal body, MIRROR LOCKUP, eye control, etc. You'll regret it if you don't.

[mauro_franic]

Rishi, I'd benn tinkering with Ektar and the different levels of ICE. I', almost tempted to weite an article with the findings but people will get tired of me.

 

In short, NO ICE is my clear preference with Ektar. I can have a masked layer with ICE FINE to get rid of any spots.

[finny99]

Man I had a Elan 7 and sold it a while back, regret it now, then again it wasn't a 7NE. Will check it out on the Bay. Cheers.

[kelly_flanigan1]

Re <i>Roger: In 1984 we didn't have the technology to scan the Ektar 25 negs</I><BR><BR>There were early drum scanners in 1984; but no Ektar 25; since it came out in 1988 to 1989. Thus this might prove some existance of a time traveler here? ie scfi or x-files stuff!

[rishij]

<i>"Stockholm syndrome?"</i>

<p>

Wait, Vijay, I don't get it -- who's my victimizer? Or was the thread that traumatic for everyone involved? :)

<p>

Mauro -- if you get a chance, you should post your ICE results. Certainly the difference between 'off' and 'ICE

Fine' are compelling (for the use of 'off' :)

<p>

Also, if you get a chance to take that Velvia 50 shot of the resolution chart, and do the same 'off' vs. 'Normal'

vs. 'Fine' -- that'd be awesome. I wonder if it'd have as much of an effect on positive film given the extended

tonal range of a positive compared to a negative (tonal range of data actually on the film)... pretty much

shooting in the dark here, as I have no real reason to believe it'd affect one more than the other, other than

noticing how film defects (holes, scratches, dust, etc.) affect negative film much more than they affect positive

film because when there's a, say, scratch or hole, a larger final tonal range (after inverting & processing the

negative) is affected since that scratch/hole existed in a medium with a very 'flat' tonal range (and since that

'flat' tonal range is later extended, any defects are amplified). I don't know if that was a good explanation.

Hopefully someone gets it.

<p>

Rishi

[vijay_nebhrajani]

<i>Rishi: "Wait, Vijay, I don't get it -- who's my victimizer? Or was the thread that traumatic for everyone involved? :) "</i>

<p>

The latter - everybody felt traumatized by everybody else and now everybody is bonding... where's Petrana?

[kelly_flanigan1]

PHOTO.NET has several main threads that have been rehashed over the last decade many thousands of times. <BR><BR>(1) Folks buy a gooberflex digital and ask how BIG can I enlarge the image.<BR><BR>(2) Folks learn that slides have less dynamic range than a negative.<BR><BR>(3) Folks learn that many digital sensors have a less dynamic range than a negative.<BR><BR>(4)Folks learn that a raw digital file can have more range than a jpeg<BR><BR>(5) Folks who post giant images on the web and learn that they got borrowed and stolen<BR><BR>(6)Folks who learn that having more ram makes their Photoshop computer work better<BR><BR>(7)Folks who learn that a high contrast lens test shot with camera bolted to a granite block give great resolution numbers to brag about.<BR><BR>(8) Folks who learn that disc drive can carsh and "learn" that they should havce had a duplicate file<BR><BR>(9) ZILLIONS OF FOLKs who are are lost souls; who crave an exact megapixel equalvalent for 35mm film; often posting results. The same folks probably want and can prove the number of MP3's per 13 year old girl; shoes per woman, lenses per photo.neter, or beers per football game. <BR><BR>(10) Folks who buy a lens with a dinky scratch and ask others if it a matters; but do not have the ability to shoot few frames as their own test<BR><BR>(11) Folks who crave ratings on posted photos; but complain when they get negative feedback.<BR><BR>(12) More threads about film versus digital; posted like its a new subject; when its several decades old now.<BR><BR>(13) Folks who discover that scanning takes time; when its a 2 decade old known fact.<BR><BR>(14) Folks who think that cleaning off fungus from a lens "magically" removes the potholes that are etched in advanced cases of fungus.<BR><BR>(15) Folks who worry about Macs versus PC's instead of worrying about results delivered to clients.

[mauro_franic]

Velvia seems to like ICE better in my opinion too. I will post the three shots on Velvia 50 on Saturday when I get them back.

 

ICE TEST ON EKTAR: A good way to observe the differences in ICE is to have the 3 layers lined up and play turning them on and off (I already prepared it in photoshop). So I posted a photoshop file - 22MB. All layers have equal sharpening.

 

 

https://www.yousendit.com/download/TTZtQmtRdWNqV0R2Wmc9PQ