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mikeber
27-Sep-2009, 12:37
Hi,
I am new to the forum and a relative newbie to LF cameras, although I have years of experience in photography. At present I use mostly DLSRs.
Maybe because of the digital experience, I am asking myself if I could use only negative color emulsions with my 4x5 camera, instead of carrying both color and B&W films.
How will scanned color exposures look when transformed by my film scanner or Photoshop into monochrome images? Will an original Tri X negative be significantly better?
Thanks,
Mike

BrianShaw
27-Sep-2009, 12:44
Mike, others will hopefully answer with technical details (I could learn from that too), but here's why I shoot B&W when I need to scan: 4x5 B&W is a lot cheaper/easier to get processed than 4x5 C-41. Whenever shoot color to scan I shoot E-6 because it, too, is a lot cheaper/easier to get processed than 4x5 C-41. In my area most of the labs have long ago stopped doing any 4x5 C-41 processing, and most have stopped their E-6 machines. Near the university is one lab that does 4x5 E-6 and B&W... so those are my chosen options. Translated -- check out your processing options before you commit to LF C-41!

percepts
27-Sep-2009, 12:50
Impossible to answer that question because colour film and black and white film have completely different response to light. So they are not the same. But some images in colour convert to black and white very well and others very badly. All depends on tonal distributions in each individual image. And that of course is under your control as photographer by selecting the subject and lighting conditions for what you want to do.
Having done it, will it look like Tri-X ? Probably not, but if that is what you want then why bang your head against the wall by using the wrong tools unless its purely because you can't be arsed to do it with the right tools.... That's your choice and no one here can make that decision for you...

r.e.
27-Sep-2009, 12:56
He's in New York and won't have any problem getting 4x5 processed.

Mikeber,

There are lots of people shooting in colour - reversal or negative - and converting to black and white when desired. There is a loss of latitude/tonal range and a different look. I've been experimenting with this, and so far I'm happy with the results, but I haven't done it enough yet to express hard and fast opinions. However, I believe that there are people who frequent this site - especially professionals like yourself - who are in a position to give some solid advice. I'll be following along myself. You'll also find some previous threads on this subject, worth reading.

BrianShaw
27-Sep-2009, 13:08
He's in New York and won't have any problem getting 4x5 processed.


I'm in Los Angeles... and I do. 4x5 C-41 is the bigger problem. If NY doesn't have this problem maybe I'll be moving there!

r.e.
27-Sep-2009, 13:13
Unless things have changed in the last six months, neither E-6 nor C-41 is a problem in New York. Start packing your bags :)

Lenny Eiger
27-Sep-2009, 14:22
Hi,
I am new to the forum and a relative newbie to LF cameras, although I have years of experience in photography. At present I use mostly DLSRs.
Maybe because of the digital experience, I am asking myself if I could use only negative color emulsions with my 4x5 camera, instead of carrying both color and B&W films.
How will scanned color exposures look when transformed by my film scanner or Photoshop into monochrome images? Will an original Tri X negative be significantly better?
Thanks,
Mike

B&W film has a longer range than color film. Generally better....

Lenny

theBDT
27-Sep-2009, 14:39
It has been my understanding that B&W has a higher effective resolution than an equivalent ISO color film, if anything because B&W does not have to split itself up into various color sensitized layers. I could be wrong...

sanking
27-Sep-2009, 14:51
Hi,
I am new to the forum and a relative newbie to LF cameras, although I have years of experience in photography. At present I use mostly DLSRs.
Maybe because of the digital experience, I am asking myself if I could use only negative color emulsions with my 4x5 camera, instead of carrying both color and B&W films.
How will scanned color exposures look when transformed by my film scanner or Photoshop into monochrome images? Will an original Tri X negative be significantly better?
Thanks,
Mike

There are a number of trade offs that you will have to evaluate for your own work.

Here are the considerations.

1. For the same ASA B&W film is sharper than color negative film, though in 4X5 and larger size you would not see much difference on the print, unless the print is very large. Portra 160 will be about as sharp as Tri-X, but not as sharp as Tmax-100. TMY will be a lot sharper than Portra 400, and also have much less grain.


2. B&W film has a much longer tonal range, i.e. you can capture on the film a much wider subject brightness range. The range for color negative film is about 12 stops, with the right B&W film and proper technique for exposure and development you can capture 18 stops and more.

3. If you scan color negative film in RGB you will be able to adjust the individual color layers of the digital file to control tonal values. This is a very powerful tool and perhaps the most important reason to use color negative film when you want a B&W print.

4. Shooting B&W film is less expensive for the same format than color negative film.

My bottom line on this is, if I want to make both color and B&W prints of a given subject I will probably use only color negative film in the field. If my goal is to make only B&W prints, then I use B&W film.

Sandy King

r.e.
27-Sep-2009, 15:18
Mikeber,

When I said that I was going to keep my mouth shut in deferrence to some people here who know this subject, Sandy is one of the people that I had in mind.

If you have Photoshop CS3 or CS4, and haven't already tried it, you might find it instructive to play with one of your colour digital photogaphs with the Black and White Conversion tool that was introduced with CS3.

Gordon Moat
27-Sep-2009, 16:27
It has been my understanding that B&W has a higher effective resolution than an equivalent ISO color film, if anything because B&W does not have to split itself up into various color sensitized layers. I could be wrong...

The best test results I have seen for colour film has been Fuji Astia 100F and Kodak E100G (and E100GX). Compare those to B/W ISO 100 films, and you will find that the B/W films have around 10% or more potential resolution capability, and a greater tonal range.

To the original poster of the queston, given testing done by Chris Perez (http://www.hevanet.com/cperez/testing.html) and others, it seems that many 4x5 lenses max out on resolution at a level below that of many films, whether colour or B/W. What I get out of that is you can safely use any modern film and get quite good resolution.

Then what that leaves is tonal range, and tonal response. If you really want B/W prints, then starting with B/W films will likely give you better results and more options. If what you really want is to shoot a ton of colour, and then sometimes have a B/W image, then the conversion method might work okay.

The only real way to tell would be to test two films (or three) at the same location under similar lighting, and then see which results you preferred. Sure, you can post process later to convert the image, but then do you want more time on the computer, or more time on location with the camera?

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

Greg Gibbons
27-Sep-2009, 17:03
I'm in Los Angeles... and I do. 4x5 C-41 is the bigger problem. If NY doesn't have this problem maybe I'll be moving there!

Samy's camera in Santa Barbara does C41 and E6 in 4x5.
Not sure if Samy's in LA does, but ask.
If not, Santa Barbara Samy's does pretty quick mail turnaround.

rguinter
27-Sep-2009, 17:25
Unless things have changed in the last six months, neither E-6 nor C-41 is a problem in New York. Start packing your bags :)

Any suggestions for a lab or two in NYC downtown to do 4x5 processing? I've been focusing solely on medium format the last several months because the local lab I was using can no longer do my 4x5. I'm close enough and willing to hand carry my 4x5s into New York for B&W, E6, and C-41. Suggestions would be welcome. Cheers. Bob G.

BrianShaw
27-Sep-2009, 18:53
Samy's camera in Santa Barbara does C41 and E6 in 4x5.
Not sure if Samy's in LA does, but ask.
If not, Santa Barbara Samy's does pretty quick mail turnaround.

Thanks Greg. A&I is the last 4x5 C-41 processor I know of in LA. I'll ask at Samy's though. If not... a drive to SB is generally a very pleasant experience. (... and might be easier than moving to NY!)

Lenny Eiger
28-Sep-2009, 08:33
If you have Photoshop CS3 or CS4, and haven't already tried it, you might find it instructive to play with one of your colour digital photogaphs with the Black and White Conversion tool that was introduced with CS3.

With all due respect, I would advise against this. I think the tool misses the mark. When I convert to b&w from a scan, there are only two concerns. 1) To get all the tonal quality I can get and 2) to use the channel(s) that have the least noise.

That last one is important to me. If you look at the channels at 100%, you will see a marked difference between the red channel and the others. PhotoShop's conversion uses around 69% red, 18 green and the rest in blue. (I don't remember the exact numbers, someone else can fill this in.) That's almost 70% of the wrong channel, in my opinion. I use none of the red in my conversions. I use either only the green or a mix of the green and blue, depending on what I see in the channel (most detail, less noise).

The conversion tool shows you different tonality choices you can make from choosing different channel settings. It's an interesting study. However, all the choices for tonal correction can be made with curves. If you want a smooth, less noisy print, forget this conversion tool, use the channel mixer to do your conversion, and use the curves to do tonal correction, which is what curves do very well.

Lenny

Leonard Evens
28-Sep-2009, 09:19
You can use color negative film and then make b/w prints, but you won't get the same results you would with b/w film. The spectral responses of the films are entirely different. If you scan, just scan as b/w. With an enlarger, you have to use special papers to print b/w from a color negative. Any decent processing lab should be able to produce a b/w print from a color negative.

I use primarily color negative film, Portra VC 160 and Ilford HP. That does mean I have to carry more film holders, but I don't find that a problem. When I travel, I take along a Calumet `Changing Room' which allows me to change flim. If going by car, I use a cooler and ice to carry film. Otherwise, hotel/motel rooms may have refrigerators, or, in a pinch you can use an ice bucket.

I process my b/w film in my bathroom, which I've arranged to use as a darkroom for that purpose and for loading film. I use a processing tube on a roller base to process 4 sheets at a time.

sanking
28-Sep-2009, 12:07
You can use color negative film and then make b/w prints, but you won't get the same results you would with b/w film. The spectral responses of the films are entirely different. If you scan, just scan as b/w. With an enlarger, you have to use special papers to print b/w from a color negative. Any decent processing lab should be able to produce a b/w print from a color negative.



The spectral responses of different B&W films vary a great deal also. So, strictly speaking one would not get the exact same results with two different B&W films, say FP4+ and Tmax-100. So, while the results you get with a specific color film converted to B&W may not exactly match what you would get with a specific B&W film I think most people would be hard pressed to tell which result came from the color negative film and which came from the B&W film, based on spectral response. From personal experience I am reasonably confident that the results I get from scanning color negative film and converting to B&W are very close in terms of the overall "look" that I get from using B&W film.

However, B&W film generally has higher resolution and finer grain than color negative film of the same ASA.

Sandy

sanking
28-Sep-2009, 12:14
With all due respect, I would advise against this. I think the tool misses the mark. When I convert to b&w from a scan, there are only two concerns. 1) To get all the tonal quality I can get and 2) to use the channel(s) that have the least noise.

That last one is important to me. If you look at the channels at 100%, you will see a marked difference between the red channel and the others. PhotoShop's conversion uses around 69% red, 18 green and the rest in blue. (I don't remember the exact numbers, someone else can fill this in.) That's almost 70% of the wrong channel, in my opinion. I use none of the red in my conversions. I use either only the green or a mix of the green and blue, depending on what I see in the channel (most detail, less noise).

The conversion tool shows you different tonality choices you can make from choosing different channel settings. It's an interesting study. However, all the choices for tonal correction can be made with curves. If you want a smooth, less noisy print, forget this conversion tool, use the channel mixer to do your conversion, and use the curves to do tonal correction, which is what curves do very well.

Lenny

I use the B&W conversion tool in Photoshop CS3 and find it to be a very powerful tool. Before I do the conversion I look at the R, G and B channels and if there a significant difference in terms of grain in one of the channels I apply noise reduction to this channel. Interestingly, it is the Blue channel that usually has the most grain on my scans, not the Red.

Throwing away one of the channels may be fine for artistic reasons but it will dramatically change the relationship of the tonal values of the original scene in a way that the use of curves may not be able to re-capture.

Sandy King

Lenny Eiger
28-Sep-2009, 12:35
Interestingly, it is the Blue channel that usually has the most grain on my scans, not the Red.

Response of PMT channels would be expected to be different from CCD.


Throwing away one of the channels may be fine for artistic reasons but it will dramatically change the relationship of the tonal values of the original scene in a way that the use of curves may not be able to re-capture.
Sandy King

The light from our b&w negs is getting split into three channels, with filters. The generally accepted idea about which one represents the least amount of distortion from the original is the green. It is often called the luminosity channel for this reason. I don't believe it represents a departure from the original balance of the scene.

I didn't make this stuff up - I learned it from guys like Bruce Fraser... and Blatner.

I'm rushing, so if this sounds terse, I don't mean it to be... got to get to my girl's school play.

Lenny

sanking
28-Sep-2009, 12:49
Response of PMT channels would be expected to be different from CCD.


The light from our b&w negs is getting split into three channels, with filters. The generally accepted idea about which one represents the least amount of distortion from the original is the green. It is often called the luminosity channel for this reason. I don't believe it represents a departure from the original balance of the scene.

I didn't make this stuff up - I learned it from guys like Bruce Fraser... and Blatner.

I'm rushing, so if this sounds terse, I don't mean it to be... got to get to my girl's school play.

Lenny

Lenny,

Exactly which of the three colors represents the most radical departure from the scene depends on the scene. Standard color separation photography with B&W film will quickly show you that throwing away one of the colors may grossly distort the original tonal values of the scene. Green is in the center of the spectrum and may give the best average, but throwing away the Red or Blue channel will distort those values.

I am not making this up either. I have actually made a lot of color separations on B&W film and combined them to make a full color image.


Sandy King

Lenny Eiger
28-Sep-2009, 12:58
I am not making this up either. I have actually made a lot of color separations on B&W film and combined them to make a full color image.
Sandy King

Hmmm.... that's interesting. I think there's plenty more to learn about this. I'm not at all satisfied.

Lenny

Robert Hughes
28-Sep-2009, 13:01
Lenny,
Green is in the center of the spectrum and may give the best average, but throwing away the Red or Blue channel will distort those values.

Which, of course, is exactly what you do when you use a green filter. Another example: Check the red channel on some color landscape shot and see the dark sky you get - just like a red filter.

cjbroadbent
28-Sep-2009, 14:44
Converting from colour to B&W with photoshop teaches you a lot about what amazingly subtle things can be done with the right filter on panchromatic film.

sanking
28-Sep-2009, 15:31
Converting from colour to B&W with photoshop teaches you a lot about what amazingly subtle things can be done with the right filter on panchromatic film.

Excellent observation. In some ways it is like you are standing there with the original scene in front of you with every filter in the world at your disposal.

And there is more. With the proper use of the conversion to B&W filters in Photoshop it is possible to dramatically extend the useful dynamic range of color negative film. I just printed an image from inside of a cave with a shaft of light illuminating a large Buda, but with the rest of the cave in very low light. I did not measure the SBR of the scene but from recollection it must have been at least 16-18 stops, normally way more than the dynamic range of color negative film. Yet with the proper use of the filters in the B&W conversion it was possible to retain detail in the deepest shadows of the scene and in the brightest highlights.

Sandy King

Greg Blank
28-Sep-2009, 15:38
The question then worth asking, in my view is did you originally make one exposure or two-three and combine them in PS? If it was more dynamic range than the film could render how did you do it?


Excellent observation. In some ways it is like you are standing there with the original scene in front of you with every filter in the world at your disposal.

And there is more. With the proper use of the conversion to B&W filters in Photoshop it is possible to dramatically extend the useful dynamic range of color negative film. I just printed an image from inside of a cave with a shaft of light illuminating a large Buda, but with the rest of the cave in very low light. I did not measure the SBR of the scene but from recollection it must have been at least 16-18 stops, normally way more than the dynamic range of color negative film. Yet with the proper use of the filters in the B&W conversion it was possible to retain detail in the deepest shadows of the scene and in the brightest highlights.

Sandy King

sanking
28-Sep-2009, 16:01
The question then worth asking, in my view is did you originally make one exposure or two-three and combine them in PS? If it was more dynamic range than the film could render how did you do it?


Only one exposure, no HDR involved. The key was in 1) exposing for the shadows, and 2) the fact that the difference in color of the light inside the cave and the light from outside allowed selected reduction via color filtration of the light entering the cave from outside.

The interesting thing about color negative film is that no mater how much exposure you throw at it the film and method of development prevents Dmax from going beyond what most scanners can capture. Normally the very high values are impossible to use because at a certain point they compress, and then level out. But all of the colors don't level out on the same curve!! This is what makes it possible, on conversion to B&W, to capture a much wider dynamic range than would normally be possible.

Or so, that is what is seems to be.

I will try to post a .jpeg of the image in question later this evening.


Sandy

mikeber
28-Sep-2009, 19:02
Thanks a lot, guys! That's fantastic!
The spirit on this forum far exceeds others. LF photographers seem to have much in common and I am glad to be here.
As for my question - it's a matter of convenience and efficiency:
For years, I developed and printed all B&W images in my darkroom. However, now I don't have access to one. I send all my chromes and negatives to be developed by a pro lab in the city. They do a good job with color processes (C41, E6). These are standard and once we match calibration it works well. B&W though, is different. I tried communicating with the lab but probably because of the many variants, results were less then satisfactory. Therefore, I was thinking of shooting exclusively in color and only later convert the ones I am interested into B&W in Photoshop. That would also save the hassle of carrying B&W film holders with me.
However, as many mentioned, the B&W negative has potential for greater latitude and I may miss that in critical shots.
Another issue is the use of filters in B&W. Instead of using red or green filters on my lens and compensate exposure accordingly, I can shoot straight without filters and later apply them in PP. These 2 ways seem to be compatible, if I am not wrong. Skipping filters when using a large and slow camera is a bonus in the field.

sanking
28-Sep-2009, 19:32
OK,

Here is the image I promised. Made with color negative film with an extreme SBR from highlights to shadows, well over 18 or 19 stops. One exposure on Portra 160 NC.

Film scanned in RGB, converted to B&W with Photoshop CS3.

The print is a carbon transfer made with a warm umber tissue.

Sandy King

rdenney
29-Sep-2009, 13:09
Another issue is the use of filters in B&W. Instead of using red or green filters on my lens and compensate exposure accordingly, I can shoot straight without filters and later apply them in PP. These 2 ways seem to be compatible, if I am not wrong. Skipping filters when using a large and slow camera is a bonus in the field.

This is ultimately what led me to using color film--plus the issue you mentioned about finding labs who can do black-and-white the way I would do it in my own darkroom.

The ability to fine-tune the effect of filtration is not to be underestimated. In the field, we have to choose between 1.) the filters we have, and 2.) the filters that are made. When I shot black and white, I had red, orange, deep yellow and yellow filters. In Photoshop, I have red, really-really-red, only-a-little-red, just-a-bit-of-yellow, amazingly-blue, jeeze-is-this-ortho-film-blue, and everything in between. I did this going back to earlier versions of Photoshop, using the Channel Mixer and setting the controls to monochrome output. Then, just experiment like crazy. I still rather prefer the Channel Mixer to the Black and White Conversion tool because the controls are bigger on my screen and easier to control with the mouse. But they do the same thing.

Story: My wife made an image with her D300 in basically perfect light for the subject. The photo was really excellent in photographic terms. But she, being utterly non-technical, didn't realize that the ISO setting of her camera as 6400. The images were massively noisy and grainy. She took it to her lab technician (me) and he advised her to consider converting the image to black and white, which was more suitable for the old-fashioned subject matter in any case. She wisely listened to her lab tech. The conversion to black and white just about completely eliminated the effect of the extreme noise level of the high ISO, not by selective noise reduction, but by minimizing the effect of the noisiest channel, and mainly by making color noise (which screams DIGITAL) look more like film grain. The grainy look supported the vintage look. The image is limited in enlargeability, and I wish there was more to be pulled from the deep shadows, but the conversion made a good, usable image out of a noisy mess. Nobody looking at that image would have any idea of its troubled past.

Rick "who learned about channel-specific noise reduction in this thread and now must experiment" Denney

Greg Blank
29-Sep-2009, 16:08
Well done :) Thanks for the details!


OK,

Here is the image I promised. Made with color negative film with an extreme SBR from highlights to shadows, well over 18 or 19 stops. One exposure on Portra 160 NC.

Film scanned in RGB, converted to B&W with Photoshop CS3.

The print is a carbon transfer made with a warm umber tissue.

Sandy King