Shadow detail & flatbeds

[Al Seyle]

I've seen references suggesting one of the shortcomings of consumer-level flatbed scanners is their inability to dig out shadow detail from transparencies (compared to drum scanners). Conversely, does that mean they also have trouble getting highlight detail from color neg? Seems logical--but what is your experience?

[tim atherton]

I think, not necessarily, because the density range of neg film is less than that of transparency (I think I've said that the right way round...) for one thing?

I get comparatively good highlight detail from negative film on my flatbed.

[Ted Harris]

Tim is right, the issue is with shadow detail from trannies. OTOH you should see for yourself if the loss of shadow detail is significant enough to matter to you. A lot will depend onhow large you print. That said I absolutely see the difference but I am hyper picky.

[Al Seyle]

To put put it more to the point, would shooting color neg and scanning on a 4990 produce a scan with more tonal range than shooting chrome?

[Ted Harris]

Maybe and maybe not. All depends on the negative in question, the way the film was shot and scanned, etc. There really are no magic bullets here. The DMax of the 4990 is 2.25 which is significantly less than the tonal range of most olor neative film and definitely less than that of most transparency film. You may 'see' more apparent range but if you re dealing with a full range negative then something will be lost. It may not be noticable in smaller prints, that was my point above. It may also not be noticable depending on how you manipulate the colors.

The diference between the 4990 at 2.25 or even the Microtek 1800f at a bit over 2.5 is still no comparison to the drum scanners and high end flatbeds that deliver in the range of an honest 4 which equals or exceeds the range of all films I can think of. There is no getting around that you will see the difference in the final print. In smaller prints it will be subtle but will become more and more obvious as you print larger.

[Michael Heald]

Hello! I'm confused by the scan to paper transition and the importance of Dmin and Dmax. From The Print by Ansel Adams, most papers seem to have a density range of about 2.1 (Dmin to Dmax range). Does this corresond to density ranges on digital prints?

I would think that digital prints have much less Dmin to Dmax range than the 4.0 that one can obtain from drum scans of negatives. In such cases, is there an advantage to such a high density range from a drum scan?

I know that the better the density range obtained, the more image editing that can be performed, but presuming a reasonably good negative that does not require much editing, how much difference would be seen on larger prints, say 16x20, with good scans made on a drum scanner with a Dmax of say 4 and a consumer flatbed that has a Dmax of 2.2? I don't mean sharpness or detail, but purely from density range?

Thank you and best regards.

Mike

[JW Dewdney]

Michael,
There is always a compression of DR from film to print - it's just the nature of the material. Anything transparent, generally speaking is going to have a higher DR - whereas reflective surfaces are limited by the substrate.

But generally speaking - no, most consumer flatbeds are very poor (IMO) in the tonal accuracy and DR dept. You'd generally see a HUGE difference between, say, an epson flatbed and a drum scanner. I recall getting some Imacon scans done and having to throw them out and get everything re-scanned on a drum. They just didn't compare.

However, that being said, there are certain photographs which will easily bear being scanned with an epson, say, and look just superb - maybe even better, when printed out. You really have to experiment for yourself.

[Jon Shiu]

Can the scanning experts comment on noise in tranny shadows, or in neg highlights?

Jon Shiu
Elk, CA

[Brian Ellis]

Michael,
But generally speaking - no, most consumer flatbeds are very poor (IMO) in the tonal accuracy and DR dept. You'd generally see a HUGE difference between, say, an epson flatbed and a drum scanner.

What's "tonal accuracy" of a scan mean in this context? Are you saying that if I meter something and place it on Zone VII for example that I can't get a Zone VII density out of my consumer level scanner? Or if I meter something that reads as a Zone V that it won't scan as a Zone V? Hopefully that isn't what you mean but if it isn't then what do you mean?

Apart from that, the problem with statements like the above is they take no account of several variables, including size of print, type of photograph (primarily whether there is a lot of important shadow detail in the film or not), and most importantly, skill of operator. John Sexton made better prints using his Saunders enlarger than I made with my Beseler. That didn't mean Beseler enlargers were inferior, it meant I wasn't as talented a printer as John Sexton. Similarly, some people are better at scanning than others. Talented people often can make better scans using inferior equipment than no-talent people will make using the best equipment (or, at a minimum, can cut the difference down to minimal rather than HUGE). So condemning an entire type of scanner without qualification as to size of print, type of photograph, and skill of operator is IMHO wrong.

[Bruce Watson]

To put put it more to the point, would shooting color neg and scanning on a 4990 produce a scan with more tonal range than shooting chrome?
No, it wouldn't. Scanners only scan what's there. They will take the density range of the film in question, be it 3.0 or 0.3, and fit it to their output digital range (0-255 for 8 bit, 1-4095 for 12 bit, etc.). This mapping from analog to digital doesn't create tone, but it may stretch it or compress it to fill the output digital range.

The result is a digital file that runs from approx. black to white, and is a perfect match to the output medium, assuming that the printer is linearized (B&W) and/or has a good ICC profile (color). I'm doing a lot less dodging and burning with inkjet than I did in the darkroom. This is why.

[Michael Heald]

Hello! I'm still confused about DMax the diffrerence between commercial flatbeds and drum scans when the final output is expected to be prints. I realize that the actual negative scans will show a large amount of difference. Will this translate into a large difference in the output print? At what size would it become apparent? This will probably even vary with the trraining of the viewer.

For example, ignoring sharpness for a moment and only considering Dmax, for a reasonably good negative that doesn't need much editing, what kinds of differences can one expect for a digital print for 8x10 through 16x20? I realize that variables need to be controlled such as paper, printer, and the skill of the operator, etc., but this applies to just about anything.

So, presuming these variables are constant (a big IF I grant you), what types of differences in the final print can be expected?

The reason I find this important for myself individually is to answer the question - how much am I willing to pay for a particular quality improvement in my photographs? This not only applies to scanning but to other equipment, training, skill development, etc. Thank you and best regards.

Mike

[Ted Harris]

Part of the problem is that I am not sure we are all using the same language throughout this thread. Bruce is absolutely correct and his statements are right on point but I am not sure that some of the questions are that absolute. I suspect that some of what Michael and Al and John are questioning is very subjective.

Michael, the variables that you note need to be controlled are huge and they start with the scan. How and where you set the white and black points for instance and whether you do it using a 'virtual' densitometer supplied with the scanning software or do it visually and how your selections would differ form someone else’s will set the amount of information in the scan at the high and low end of the tonal range ... and the way you do it can easily be very different than the way someone else does it based on a lot of externalities such as your ambient lighting and monitor or how carefully you monitor with he densitometer. It is impossible to just dismiss these variables.

Now for your second question which is the one we are all asking even if we don't say it out loud ... how much are we willing to pay for what level of quality? It's an individual decision. How do you make decisions on which lenses to buy? How your film gets processed, etc? The same sort of criteria should apply here. If you are doing this for your own enjoyment and $$ do count then the question should be how much can I afford to spend and is it enough to get me a print that I like? That answer can, of course, change over time. The differences we are talking about are similar to those you hear about a variety of different lenses of the same focal length or more to point about the differences of rigidity of various enlargers, quality of light from different light sources and differences in enlarging lenses. Just as a simple example the price range between a 'decent' older 150mm enlarging lens and the latest Apo Componon HM is probably $100 o $1500; where along this spectrum are you comfortable? I know that years ago a Componon worked fine for me and would it still be ok today now that I have seen the resolving power, etc. of the latest lenses? Personal choice. If, on the other hand, you are doing this for a living and your ability to snag the next job depends, in part, on being able to deliver images that are more compelling than those delivered by the competition you want to make sure you are not constrained by your equipment ... never forgetting that equipment will never substitute for talent and creativity.

Having said all this you might want to consider a few things: 1) take a negative that meets the 'normal' criteria for you and scan it on a 4990 or equivalent scanner then send it out to have the best scan possible made by a lab ... print from both and see if the difference matters to you; I do this all the time and know it matters to but I can also see as I keep saying that it may not matter to others for smaller prints if proper skill is exercised with the less expensive scanner. 2) From what I recall of past threads I believe you are self-taught, at least in this aspect of photography. You might want to consider some sort of training or workshop that will at least let you further develop your thinking on what you need and where you want to go. Not a semester in a University but a weekend or week. Doing this will also let you try out lots of equipment an exchange ideas and experiences (and even prints) with others. A workshop is probably the least expensive and most rewarding way to answer your questions. I'll sound my horn for a sec. For example, if you come to one of our weekend scanning/digital workflow workshops you will get to do exactly what I am talking about .... scan and print the same negative on a variety of scanners and papers and even different printers. With my new studio and workspace we will run some workshops here, in New Hampshire and that will mean that participants will have available several different consumer flatbeds and a Screen Cezanne so you will be able to do a real time comparison between the low end and high end equipment and decide for yourself on the spot if sending out for scans is worth it to you. Other workshop may also offer the same thing. You can also see if a full service printer will let you do some work there. Before I got deeply involved with digital imaging I spent literally weeks observing, working and listening to pros in three different prepress houses and labs. I got my early 'training' by bartering my skills in a traditional darkroom for their skills in the digital world. If there had been classes/seminars available then I would have taken them too.

Bottom line, others and I will keep sharing our experiences here but sooner or later you gotta hold your nose and jump in the water ... come on in, the water is warm and we will not let you drown!

[Michael Heald]

Hello! Ted, I'm hoping to attend one of your upcoming scanning workshops and I appreciate your input and guidance that I'ce received in this forum.

I amstill puzzled by the math, and it may be that the math is tripping me up. If a drum scan has a Dmax of 4, for a B&W image, that would yield 10 to the 4th power levels of gray, or 10,000.

If printing paper has Dmax of 2.4, then only 256 levels an be discerned on a print. If this is so, then does this mean that the 10,000 gray levels from the scan have to be condensed to the 256levels for the final print?

If I'm understanding this correctly (which I question), then the reason that a drum scan would produce a better print (or much better) compared to, say an Epson 4990, wouldn't have to do with the difference in Dmax between the two scanners (4.0 and 2.4), since they both would condense the gray scales down to the final paper DMax of 2.4 (unless a lot of editing is anticipated - the same reason to scan in 16 bit rather than 8bit?).

The reason to use a drum scan (of high end flatbed) would be the other factors that affect a scan, such as optical quality and the sharpness of a scan, mechanical quality to minimize vibration, and software quality for processing the raw images?

In other words, given a negative that doesn't require much editing, once the true DMax (not claimed/stated) of a scanner exceeds that of the output paper/medium, does this mean that Dmax becomes relatively unimportant and that the other variables then become much more important in evaluating a scanner's performance - such as optical and mechanical build quality? Best regards.

Mike

[Bruce Watson]

...presuming these variables are constant (a big IF I grant you), what types of differences in the final print can be expected?
You'll have to try it and make that decision for yourself.

The metaphor I sometimes use to descibe the differences is that of a window between you and scene. Think about the glazing you would use in framing. You can use hardware store plexiglas, Tru Vue Museum Glass, or something in between. At the low end is less than perfect optical performance (distortions, haze, glare, color shifts) while at the high end you get excellent optical performance. You can go to most framers and hold samples of the various glazing options in your hands and evaluate them yourself.

This is more or less what you are talking about as you go from low quality scans to high quality scans.

Remember too that the scan is the front end of the workflow leading to the print. Everything builds on it.

[robc]

I am still puzzled by the math, and it may be that the math is tripping me up. If a drum scan has a Dmax of 4, for a B&W image, that would yield 10 to the 4th power levels of gray, or 10,000.

Wrong! dmax 4 refers to density range and is expressed in logarithms. Dmax 4 means the the scanner can handle a neg/pos of density range 4 which is 12.3333 stops, each stop being 0.3 logD. A typical B+W neg usually has a density around 1.5logD i.e. 5 stops. A tranny has ??? someone will enlighten us but it is likely less than 4logD.

So scanner Dmax 4 means simply that a scanner is capable of pulling detail from something which has a density of 4logD.

Dmax has nothing to do with levels of gray. That is simply colour depth which is a function of the hardware and software and not the neg/pos

[robc]

Just to add:

the figure of 10000 which you calculated is the "opacity" of the neg/pos expressed as a relative term. i.e. it passes 10000 times less light than the clear part of the neg/pos.

4 is the base 10 logarithm of 10000.

Appendix 5 of AA's The negative explains all this in simple terms.

[Michael Heald]

Hello! I thought Dmax was the highest or whitest level that the scanner could detect a difference between adjacent light levels and Dmin was the darkest? For a Dmax of 4, the highest or whitest level would be 10,000 times more intense than the blackest? In this regard, I am using tone or white level only with regard to intensity or amount of light, and not to color or chroma.

With silver B&W, different tone is achieved by the build-up of silver. For a negative, the more silver, the darker the area and the less light is transmitted. For a print, the darker area, the less light is reflected.

For a B&W negative, if Dmin is 0.3 above base+fog, does this mean that that amount of light is 10 raised to the 0.3 less than the amount transmitted for the base +fog, or that one-half the amount of light is transmitted in thsi zone as is transmitted for base + fog? From what I've read, folks place this value on Zone 1 of the Zone System, so Zone 1 would darker than zone 0 which would be film base + fog. Is this correct?

Similarly, if DMax is 2.4, does this mean that that darkest area of a negative transmits less light than zone 0 by a factor of 10 raised to 2.4 or 256 times?

My main question regarding Dmax of scanners, however, is how much the expanded dynamic range is seen on the final print. Ink jet papers have about the same range is traditional silver based papers, am I correct? Once all editing is finished and the file is sent to be printed, the dynamic range of the file will still be compressed to what the paper can handle. Is this true?

Or am I confusing apples and oranges. Does the dynamic range of scanners refer to the same thing as for prints and negatives - the difference in the intensity of light from the darkest part of an image to the brightest expressed logarithmically? Thank you and best regards.

Mike

[tim atherton]

Hello! I thought Dmax was the highest or whitest level that the scanner could detect a difference between adjacent light levels and Dmin was the darkest? For a Dmax of 4, the highest or whitest level would be 10,000 times more intense than the blackest? In this regard, I am using tone or white level only with regard to intensity or amount of light, and not to color or chroma....

Or am I confusing apples and oranges. Does the dynamic range of scanners refer to the same thing as for prints and negatives - the difference in the intensity of light from the darkest part of an image to the brightest expressed logarithmically? Thank you and best regards.

Mike

This is from an old post - never sure if I get this exactly correct, but it goes something like this:

Unfortunate confusion of terms - use of the same or similar term to mean something very different. The "D" in DMax when used with regard to scanning isn't referring to dynamic range but density. Here is a definition I keep around to help me make sense of it...:

"First dRange... The "d" means density (and doesn't really have anything to do with dynamic range as such), and when measuring density that film records (as in contains valid image data), there is a minimum value (dMin), and a maximum value (dMax). The range between these two density points is the density "range", or dRange.

Positive (transparency) film has a clear base...so the dMin for it is going to be quite low...as compared to negative film, which has a cloudy base...so the dMin for negative film will be quite a bit higher than positive film. Both films will pretty much have the same max density, black is still black, whether it's positive or negative film.

Well, let's say the dMax (blackest part) of both films can be measured at 3.6...and the positive films dMin is .2; and the negative films dMin is .8... That gives a dRange for the positive film of 3.6 - .2 or 3.4, and for the positive film 3.6 - .8 or 2.8.

It's purely the film base "offset" that creates the difference in density range.

(and so you don't need the same density range to get the info out of a negative film as you do from a transparency film)

For another discussion let's say that the same range of image tonality could be recorded on either film...just that negative film would have the range compressed, film density wise that is, compared to positive film. Also, the "dynamic range" of the film is not the same as the density range...and the term dynamic range is often misused when talking about density range."

any clearer... :-)

[Brian Ellis]

"Ink jet papers have about the same range is traditional silver based papers, am I correct?"

No, I don't think that's correct. According to Ctein (in his book "Post Exposure") traditional darkroom papers had a range on average of about 2.0 log units or roughly 7 stops. I've seen the results of tests performed by various people in the Yahoo digital black and white print group using a variety of different printers, inks, and papers and the best they're getting from ink jet is about 1.7 log units IIRC. So there's about a stop difference. However, I've always liked Dick Arentz' saying, which is something along the lines of "you don't need the blackest black, you just need a convincing black." Which is why I don't think the one stop difference is important, the black I get from my ink jet prints is plenty convincing (at least to me : - )).

[Helen Bach]

There are a few different questions in your post. I'll start with an attempt to answer

"My main question regarding Dmax of scanners, however, is how much the expanded dynamic range is seen on the final print. Ink jet papers have about the same range is traditional silver based papers, am I correct? Once all editing is finished and the file is sent to be printed, the dynamic range of the file will still be compressed to what the paper can handle. Is this true?"

Ink jet prints can have a wide spread of density ranges - from about 1.5 to 2.6, ie from less than most silver gelatin to noticeably more than silver gelatin. That's a quantitative comparison. The visual appearance of the tonal range depends on the image itself. A print with shadow detail in densities between 2.3 to 2.7 needs quite bright light to be fully appreciated, and wide density range prints are quite demanding technically because they show imperfections quite well.

When a file is printed nothing can be brighter than the paper base, and nothing can be darker than the D-max produced by the paper/ink combination. That can result in a compression or expansion from the original scene brightness range, just as it can be a compression or expansion from the density range of the film original.

If you consider a film with a very wide dynamic range, say Fuji Pro 160S, it can record about twelve stops of scene brightness range. This results in a density range on the film of about 1.6 for each channel (the overall density range is about 2.5 because of the density in the blue channel of of the orange mask).

As an aside: Typical colour neg films have a D-min of about 0.2 in the red channel and 1.0 in the blue channel, because of the ‘orange’ mask. D-max might be around 1.8 in the red channel and 2.6 in the blue channel.

The full density range of the film could be scanned then printed on paper with a density range of 2.3 (for example).

Twelve stops of scene brightness range has been converted to five and a bit stops of film density range then a print made with a density range of about seven and a half stops. In most cases, that would look rather dull.

However, there is no need to print the full density range of the film. Typical colour wet print systems are designed to produce a print from the equivalent of seven stops of scene brightness range (depends on the film contrast and the paper contrast).

Best, Helen

[tim atherton]

"Ink jet papers have about the same range is traditional silver based papers, am I correct?"

No, I don't think that's correct. According to Ctein (in his book "Post Exposure") traditional darkroom papers had a range on average of about 2.0 log units or roughly 7 stops. I've seen the results of tests performed by various people in the Yahoo digital black and white print group using a variety of different printers, inks, and papers and the best they're getting from ink jet is about 1.7 log units IIRC. So there's about a stop difference. However, I've always liked Dick Arentz' saying, which is something along the lines of "you don't need the blackest black, you just need a convincing black." Which is why I don't think the one stop difference is important, the black I get from my ink jet prints is plenty convincing (at least to me : - )).

I haven't measured it, but I'm getting a much greater range on the newer papers like Silver Rag, and the Innova one than I did on any of the older papers. It must be close to that 7 stops I think

[robc]

Michael,

Scanner doesn't know whether it is looking at a neg or a pos. As far as its concerned they are the same. Its the software that you have to tell that you are scanning one or the other. Remove the software from the equation and you just have a scanner which treats dense areas which have low transmission as the Dmax areas and clear high transmission areas as Dmin.

Once again. Scanner Dmax refers to densest material which a scanner can retrieve useful information from.

[robc]

problem with quoting measured dmax of papers is this:

you use a desitometer to measure it. A densitometer measures only incident light from one direction and being reflected in another. Put a print on a wall and measure the range with a spot meter and you won't get more than around 4 stops, i.e. 1.2 regardless of what the paper is. This is because what you see is different from what the densitometer sees. you see diffused light from the print surface. High Gloss prints give better range than satin or pearl finish which is why RC prints are better than FB for range. No print lets you see 7 stops when its hung on the wall.

Just take your spot meter and measure the range from normal viewing position and see for yourself. Then compare with a densitometer and see the difference. Which is correct? The densitometer figure is purely academic since you can't see what it sees.

[Michael Heald]

Hello! Thank you all for the information. I think I'm getting a handle on terminology and how they apply to film, prints, and scanners. Best regards.

Mike

[MJSfoto1956]

*ALL* electronics exhibit noise at low levels. The ability to distinguish real data from random noise decreases as the signal is low (e.g. dark areas) -- this is the classic Signal to Noise Ratio described in detail elsewhere and fully understood for more than 50 years. While the scanner "may" be able to capture data in the dark areas the built-in noise threshold will often render the data unusable (especially true with consumer scanners). It is precisely the same thing that happens with audio -- very quiet passages are where you will hear hiss and noise.

So where does that leave us? Scan a negative with a consumer flatbed and your shadows will be clean but your highlights will exhibit noise. Likewise, scan a chrome and the opposite is true: the shadows get noisy while the hightlights are effectively noise free.

This is why so many people are "excited" about HDR in Photoshop -- take two or more exposures (e.g. one for the shadows and one for the highlights) scan both images in register, then let Photoshop "blend" them together for a High Dynamic Range photo. I first described this technique back in 1995 in my now-out-of-print layman's scanner book "Make Your Scanner a Great Design & Production Tool". Of course, this HDR technique is often abused -- just search on HDR on flickr and you'll see some atrocious images!

J Michael Sullivan
Editor/Publsher, MAGNAchrom
www.magnachrom.com (http://www.magnachrom.com)

[robc]

oops, made an error.

"density range 4 which is 12.3333 stops"

should read

"density range 4 which is 13.3333 stops"

[MJSfoto1956]

Unfortunately, the claims of dmax=4 fail to consider Signal to Noise Ratio (or distortion if you like). The postings by scanner manufacturers are reminicent of the stereo manufacturers of yesteryear claiming 20-20,000 Hz "dynamic range" (analogous to our dmax) but cleverly omitting how much distortion the measure was taken with. Dmax=4 is totally meaningless measure without a qualifier as to what the SNR is.

If you'd like to understand the issue better, you might want to read the following links thoroughly, paying particular attention to the discussion of dynamic range:

http://www.betterlight.com/rest_of_the_picture.asp
and
http://www.betterlight.com/why_better.html

The very best, top of the line scanners cannot actually acheive dmax=4 (the theoretical limit btw. Technically impossible to exceed). So if a $15,000 scanner can't do it, why do you believe a $500 scanner can? Worse, why do you believe them when they claim dmax=4.8!!?? Total bull. Consumers should demand better.

J Michael Sullivan
Editor/Publsher, MAGNAchrom
www.magnachrom.com (http://www.magnachrom.com)

[Helen Bach]

problem with quoting measured dmax of papers is this:

you use a desitometer to measure it. A densitometer measures only incident light from one direction and being reflected in another. Put a print on a wall and measure the range with a spot meter and you won't get more than around 4 stops, i.e. 1.2 regardless of what the paper is. This is because what you see is different from what the densitometer sees. you see diffused light from the print surface. High Gloss prints give better range than satin or pearl finish which is why RC prints are better than FB for range. No print lets you see 7 stops when its hung on the wall.

Just take your spot meter and measure the range from normal viewing position and see for yourself. Then compare with a densitometer and see the difference. Which is correct? The densitometer figure is purely academic since you can't see what it sees.

I've just done the test you suggest. I can easily get a seven stop range even though none of my prints have detailless shadow (ie the one degree spotmeter doesn't have a small enough spot to measure something that is all D-max).

Best,
Helen

[robc]

I'm amazed at your results. What print method, inkjet or silver and which paper was it.

Also was this in normal room lighting or under a spot lamp?

[Helen Bach]

K3 ink in a 2200 using IJC/OPM on Epson Premium Glossy. Lit with our normal room lighting, which also happens to be overhead spots. I moved a print into the bathroom, where there is less directional light, and measured six and a third stops. It was difficult to get enough light on the print to get a reading from the shadows. As I said before, you need a lot of light to appreciate a print with a high density range. Of course spot meter readings aren't the right way to judge density range, your eyes are, but densitometers provide a standardised method. A print with a high density range looks just stunning if there's enough light.

Then I cleaned the dust off the print...

Best,
Helen

[robc]

when I did the test with Ilford Gallerie which had been selenium toned, I got 8 stops in the densitometer but only around 4 stops in normal room daylight and spot meter. With spots I'd get more, but not more than around 5 stops. Thats a good argument for going to digital prints if you can easily get that much more range out of a print. Makes it much easier to get it to come alive.

Even with dust on it...

[JW Dewdney]

What's "tonal accuracy" of a scan mean in this context? Are you saying that if I meter something and place it on Zone VII for example that I can't get a Zone VII density out of my consumer level scanner? Or if I meter something that reads as a Zone V that it won't scan as a Zone V? Hopefully that isn't what you mean but if it isn't then what do you mean?

Apart from that, the problem with statements like the above is they take no account of several variables, including size of print, type of photograph (primarily whether there is a lot of important shadow detail in the film or not), and most importantly, skill of operator. John Sexton made better prints using his Saunders enlarger than I made with my Beseler. That didn't mean Beseler enlargers were inferior, it meant I wasn't as talented a printer as John Sexton. Similarly, some people are better at scanning than others. Talented people often can make better scans using inferior equipment than no-talent people will make using the best equipment (or, at a minimum, can cut the difference down to minimal rather than HUGE). So condemning an entire type of scanner without qualification as to size of print, type of photograph, and skill of operator is IMHO wrong.


Brian, please put the zone meter away.

What I mean by tonal accuracy has NOTHING whatever to do with 'zones' or 'previsualization' or anything like that. I'm really not sure why you're dragging the adams-speak into this. What I mean by tonal accuracy (thank you for asking what I mean, anyway!) has more to do with 'tonal separation' and no muddying up whole sections of a range of tones. A good drum scanner will typically be better at this.

As for your mention of my not taking 'variables' into account, that's why I used the word 'generally'. For me, it's like saying 'all other things being equal'. Yes, we assume under these circumstances the same scanner operator with the same approach and the same degree of skill for all scanners. I'm trying to be objective (i.e. - treating variables as a common object - no change).

Basically - I suppose you're bringing up a bunch of issues that I'm trying to do away with by assuming 'no variation'. I think I'm allowed to do that - Aren't I?

[JW Dewdney]

Talented people often can make better scans using inferior equipment than no-talent people will make using the best equipment (or, at a minimum, can cut the difference down to minimal rather than HUGE). So condemning an entire type of scanner without qualification as to size of print, type of photograph, and skill of operator is IMHO wrong.

To be fair - you could also say that it's possible for 'no talent' people to make superior scans (as relates to the end photograph) using inferior equipment - as the 'best people' using the best equipment. I'm sure that's true a good percentage of the time - though not really useful for the discussion. But since you brought it up...

[JW Dewdney]

when I did the test with Ilford Gallerie which had been selenium toned, I got 8 stops in the densitometer but only around 4 stops in normal room daylight and spot meter. With spots I'd get more, but not more than around 5 stops. Thats a good argument for going to digital prints if you can easily get that much more range out of a print. Makes it much easier to get it to come alive.

Even with dust on it...

I'm guessing you folks are talkin' "transmission densities" here and not reflection...? The whole discussion seems a bit moot - like saying - "oh yeah, my car does 180 mph" even though you're limited to 30mph on the municipal streets you drive it on. My point being that most realistic lighting conditions wouldn't really let you exploit information outside of, say a 3-3.5 stop DR. Don't you think so?

[Helen Bach]

I'm guessing you folks are talkin' "transmission densities" here and not reflection...? The whole discussion seems a bit moot - like saying - "oh yeah, my car does 180 mph" even though you're limited to 30mph on the municipal streets you drive it on. My point being that most realistic lighting conditions wouldn't really let you exploit information outside of, say a 3-3.5 stop DR. Don't you think so?

No, we are talking about reflection.

As I wrote in previous posts, a print with a high density range does need good lighting to get the most out of it, as you suggest. However, if you mean that there is no point in having a density range of more than three and a half stops (ie a logD range of 1.05) then I disagree. Is that what you meant?

Best,
Helen

[JW Dewdney]

No, we are talking about reflection.

As I wrote in previous posts, a print with a high density range does need good lighting to get the most out of it, as you suggest. However, if you mean that there is no point in having a density range of more than three and a half stops (ie a logD range of 1.05) then I disagree. Is that what you meant?

Best,
Helen

I'm trying to suggest that, in a 'domestic' print viewing situation - in a dimly lit hall, or in someone's study, where you're not going to have 5500K color corrected 95+CRI lightsources - but, in fact, perhaps a 30W bulb - that trying to expand DR is going to have diminishing returns - and in fact, you're probably only going to be able to SEE a small fraction of the tonal range of an eight-stop DR print. I was shooting from the hip with my 3-3.5 stop DR estimate. But it's probably not so far off, IMO. It's one of those theory/practice things, don't you think? (which is simply to say that it works and is great and everything - but only under limited conditions).