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Edward McLaughlin
30-Mar-2008, 12:33
I'm wondering if anyone else is thinking on these lines: instead of carting around a light meter (600g) and a small viewing lens to gauge potential shots prior to camera set-up (700g); perhaps a small cheap light digital camera would do both jobs?

Adam Kavalunas
30-Mar-2008, 12:53
My Pentax Digital Spotmeter only weighs 8.8 oz, and its more accurate and specific than a digital camera. I'd rather have true spot metering capability. As far as a viewing aid, I took a piece of cardbord, cut a 4x5" hole in it, and trimmed in down to about a 1/4" width all the way around. It fold up and doesn't weigh a thing. Just hold it out in front of you and guestimate your focal length by how far from your eye it is.

Adam

Wayne Crider
30-Mar-2008, 13:11
Yea I thought about it at one time. A decent idea but I wouldn't use it as a meter. I think a separate meter and framing guide is better. Still, I'd try it and report back to us what you found. Remember tho that the proportions are different and you'll need to figure out whatever focal length your using with the "D" camera that doesn't have them. Still it will give you a right side up image that works for some. If your shooting b&w, a digital b&w option would be nice. Colors seem to get in the way sometimes.

roteague
30-Mar-2008, 13:34
I'm wondering if anyone else is thinking on these lines: instead of carting around a light meter (600g) and a small viewing lens to gauge potential shots prior to camera set-up (700g); perhaps a small cheap light digital camera would do both jobs?

No, but I often do this with my Nikon F6.

Frank Petronio
30-Mar-2008, 14:17
I bet my Nikon gets the exposure right far more often than a gaggle of spotmeter-equipped zone-systemites ;-)

Seriously, spend a minute to compare your spotmeter to your digital camera's metering, make ISO allowances for the difference, and go shoot. Having a Histrogram in invaluble and a zoom lens, even if the proportions are different, makes the fancy Linhof multi-focus or those director's finders a joke.

But I'd spring for something like the cheap, tiny Nikon D60 with a compact zoom (or the small Pentax or Olympus). Something that actually uses f-stops in the same range as your lenses and real manual control. All but a few of the compact digitals make accessing shutter speed and aperture info a huge hassle and I suspect they may not be as accurate as the larger DSLRs.

timparkin
30-Mar-2008, 14:23
I always carry a 5D along with my 45SU and it serves as a perfect finder. My 24-105 is probably the best wide zoom that Canon do and makes a good 110-360 finder, but I don't use it as a light meter. My pentax spotmeter is a lot more functional and I love the mechanical calculator (very easy to 'browse' different settings and the range of exposure). The 5D is bloody heavy but it takes OK snapshots..

Ben Chase
30-Mar-2008, 15:06
Seriously, spend a minute to compare your spotmeter to your digital camera's metering, make ISO allowances for the difference, and go shoot. Having a Histrogram in invaluble and a zoom lens, even if the proportions are different, makes the fancy Linhof multi-focus or those director's finders a joke.


I don't have personal experience in this regard, but I have read about many folks who are paying far more attention to the histogram than to the EV of the meter. One example that I can cite is Robert Morrissey (Master Lighting Guide for Commercial Photographers ISBN-13 #978-1-58428-198-6).

It is no surprise that histogram information provides far more detail than most handheld meters will.

That said - it's pretty clear that both have worked pretty effectively. But I would be dubious about cheaper meters in lower-end digitals without performing some tests. If the variance is only a few tenths of a stop or so, you "probably" won't notice the difference.

EuGene Smith
30-Mar-2008, 16:35
Gosh, I used to take along one my Minolta SRT-series film SLRs with a zoom lens, set the ASA the same as the LF film speed, then zoom to approx. the same as the LF view, set the aperture & shutter speed on the SLR using the built in meter, then transferred the settings to the LF shutter. Not the most scientific means, I suppose, but it always seemed to give pretty good results. As I got use to doing it, I knew when to add in a bit of "Kentucky windage" to tweak the result a mite.

EuGene

h2oman
30-Mar-2008, 18:54
A word of warning before you read this: I have only exposed about 20 sheets of 4x5 transparency film, and have only had 10 sheets developed so far!

I have taken photos (mostly lousy ones!) on and off for 30 years, mostly 35mm slides. (Potluck, beverages and slide show!) A bit over a year ago I was going to get more serious about it, and thought digital was the way to go. I decided to test the waters by getting about the most inexpensive DSLR I could find, the Olympus E-500. (I was also swayed by it's built-in dust removal system, since I knew two Canon owners who had sent their rigs in for cleaning about a year after purchase.) It came with two "kit" zoom lenses, one equivalent to about 28-90mm on a SLR, the other equivalent to about 80-300.

I shot away, and got some decent photos, but when I showed my wife shots by Jack Dykinga and David Muench (I'm a color landscape fan), she kept saying "How come everything is so much clearer and sharper than your pictures?" I explained to her that they used large format cameras and she said "Maybe you should get one of those?" I told her it was too complicated for me, and that I'd have to buy a bunch more stuff...

So now I have a 4x5! The camera came with a 150mm lens, and I decided to hold off on a light meter and use my digital camera instead. Of my first ten developed shots, I'd say all but two were exposed right on or within 1/3 stop. One of the two bad ones was to be 5 seconds, and I tried counting "one-thousand and one, ..." The other one I believe was off because my camera did not read an "even" stop, I was using ISO 50 film and the slowest ISO on my digital is 100, and I was guessing a filter factor for a polarizing filter. After all that adjusting in my head I think I was just plain confused! About 6 or 7 of these exposures were with Velvia 50 and the rest with Astia 100, all expired film people had given me.

Here's my system:

1. First, the Olympus with the 28-90 lens is pretty light, and fits in a chest pouch I used while backcoutry skiing with a Canon Rebel I used 5-10 years ago. So the first thing I do when I go out with my 4x5 is strap on the pouch and digital camera.

2. The Olympus sensor is a "four thirds", with an aspect ratio of 4:3, or 1.33. Not too far off from the 1.25 of 5x4 (Brit style!) I set the 4x5 up in my living room with the 150mm lens and framed a "shot", then held the digital directly above and zoomed until I had pretty much the same shot framed. Put some duct tape on the zoom part of the barrel and marked that focal length on the duct tape.

3. So then I went out and took 3 photos and decided I had to have a wider lens. I picked up a 90, and found that it frames almost exactly what I get with the DSLR zoomed to 28mm (Actually 14mm with a 2x multiplication factor...) So I wander around with the DSLR, look for a scene and try it with the lens zoomed to one of the two lengths equivalent to my 90 and 150. When I get what I want I set up the 4x5.

4. I work at a college, and we got raises last summer, but weren't told how much they would be. So the raise was never really applied until after a bunch of negotiating and budget hassling. So my Feb check included all the $$$ for each month retroactive to last summer. With the economy so shaky I decided the prudent thing was to spend it all on LF gear! So I rounded out my lens selection with a Fuji 240, and I've found that it frames pretty much what the 28-90 does at its longest setting.

So that one lens performs as a "multifocal view finder" for my three lens LF kit; I use it to find a scene and select a lens. Then I set up and focus the 4x5. At that point I take a shot with the DSLR and check the histogram. In a year of using that camera I feel I got pretty good at correlating the histogram with the various tones in a scene. If I don't like what I see on the histogram, I compensate one way or the other and shoot again until I get the tones placed where I want them. I then set the 4x5 and take the shot.

One problem I was having was a bit of confusion when the DSLR didn't read a "standard" shutter speed. (I set it for aperture priority at f/22.) The final piece of the "system" is an index card on which I wrote all the sutters speeds in 1/3 stops, with the standard ones highlighted. This makes me much quicker and more confident when working in third stops.

So that's what has worked for me SO FAR. I have not ruled out getting a spotmeter, but I'm going to stick with this system until I feel a need to do otherwise. I do like the ability to compose with the DSLR before setting up the LF. One other thing I intend to try when I start doing some moving water shots is to try different shutter sppeds with the DSLR and looking at the pic right away to select the speed that give the desired blurring of the water.

Vaughn
30-Mar-2008, 21:04
Not interested at all in using a dig for either purpose.

One of the purposes of my photography is to learn how to see better without a camera. Nine times out of ten, when I set up the camera, I do not need to move it more than a few inches to get the composition I want. While using framing cards, dig or film cameras to find compositions are perfectly valid ways of working, by not using any of those one eventually learns to see compostions just as well (if not better). I do occasionally use my fingers to frame a shot if I feel the need.

Granted, I have 30 years of experience doing this and NOOB's might find it easier with some sort of compostion-finder. Also, I never really used a 35mm much -- never got into the habit of walking around composing thru a viewfinder.

Metering...my Pentax Digital Spot gives me all the info I need. If I want to know the amount of light under that bush across the creek, it is hard to beat a spot meter. A spot meter seems so easy...a low value, a high value, and perhaps a couple inbetween out of curiosity...and I have all the info I need for exposure and developing.

Vaughn

Dave Saunders
31-Mar-2008, 00:45
Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

Greg Lockrey
31-Mar-2008, 01:44
Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

You make them by cutting out a 4x5 rectangle (or whatever format equivalent you will be using) from a piece of 8x10 cardboard or any stiff material. Mine is black on one side and white on the other. Until you get used to the focal length of your shooting lens, it's a good idea to add a string of a given length to match the focal length of your lens to be placed at your chin to aid in setting up your focal distance to match your camera. Basically you just look though it to determine your composition. Once you've shot thousands of images, you will know what your camera field of view before you have it set up. ;)

Bob McCarthy
31-Mar-2008, 05:10
I tried this a year or so ago. My recommendation is "forget it"

With color, film has a much shorter Dynamic Range. And many, if not most, digital camera meters are biased to protect highlight burnout. If you just want to meter a grey card, it will work fine, otherwise it will confuse you and waste film. The new digitals have 8+ stops of DR. Film has maybe 5.

With B&W, the match up is closer on DR, but the digital thinks in terms of protecting highlights, shadows be damned. Backwards from the needs of B&W negative.

Keep your spot meter. Though I would have no problem transfering meter data from an F5 for Velvia. Any digital camera meter/histogram is biased for the conditions of that technology.

bob

Vaughn
31-Mar-2008, 09:33
Can some one explain a bit about framing cards? They sound useful especially to a noob like me (that does have to move the camera a dozen times before the shot!) Do you make them yourself, How do you work out the field of view?

If you want the viewing card to be smaller, that's fine -- as long as the proportions are correct for your format. (the smaller the card, the closer it must be to your eye to mimic the view of the same focal length lens.)

I also find closing one eye helps to eliminate the influence of our ability to see in 3D. Compositions can be thrown off the fact that foreground objects seem to be seperated from the background due to the their appearence in 3D -- that separation may not transfer to the 2D of the print...objects that are defined by their position may not be so well defined by light.

Vaughn

rippo
31-Mar-2008, 10:43
I shot away, and got some decent photos, but when I showed my wife shots by Jack Dykinga and David Muench (I'm a color landscape fan), she kept saying "How come everything is so much clearer and sharper than your pictures?" I explained to her that they used large format cameras and she said "Maybe you should get one of those?"



I would weep tears of joy if my wife ever said that to me! :)

Matus Kalisky
1-Apr-2008, 13:44
I did and do use a digital SLR as a lightmeter. It is very convenient to have a preview of the picture that you will othervise see in a week or two. For me this works but the preview on the LCD screen somehow takes the thinking a bit out of the way. Sure I do use the spot meterering feature to check the range, but in my experience what fits in the range of the digital sensor (Minolta 7D) that also fits on the film. I am not aware that my camera would give me 8+ stops of dynamc range.

The bottom line is - it works, it is relatively fast, but a DSLR is heavy and it is too easy to get a correct exposition without spot metering and findig the brightest and lightest part if the scene - so it has a tendency (at least in my case)to take the thinking away - and your intuition and experice does not grow as it possibly could without it ..

Bob McCarthy
1-Apr-2008, 14:04
http://www.dpreview.com/reviews/nikond300/page20.asp

Our new Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from (the cameras) black to clipped white (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).


Sensitivity Shadow range Highlight range Usable range
ISO 100* -5.2 EV 3.3 EV 8.5 EV
ISO 200 -4.7 EV 4.1 EV 8.8 EV
ISO 400 -5.1 EV 4.1 EV 9.2 EV
ISO 800 -5.1 EV 4.1 EV 9.2 EV
ISO 1600 -4.3 EV 4.1 EV 8.4 EV
ISO 3200 -4.0 EV 4.0 EV 8.0 EV
ISO 6400* -3.7 EV 3.9 EV 7.6 EV


* Non-standard sensitivities

Dynamic Range compared

All of the current crop of 'advanced amateur / semi-professional' digital SLRs (D300, A700, 40D and E-3) deliver around nine stops of dynamic range. The biggest difference is in the balance of the range, the D300 and A700 both deliver around four stops of highlight range (above middle gray) where as the 40D around three and a half and the E-3 around three. Both the 40D and E-3 deliver more shadow range.

Camera
Shadow range
Highlight range
Usable range
Nikon D300 (ISO 200) -4.7 EV 4.1 EV 8.8 EV
Sony DSLR-A700 (ISO 200) -4.9 EV 3.9 EV 8.8 EV
Canon EOS 40D (ISO 100) -5.7 EV 3.4 EV 9.1 EV
Olympus E-3 (ISO 100) -5.7 EV 3.0 EV 8.8 EV
Nikon D200 (ISO 100) -5.0 EV 3.2 EV 8.2 EV

joolsb
2-Apr-2008, 02:40
The new digitals have 8+ stops of DR.

I would be very surprised if digitals actually had a usable DR that big. It all depends on careful conversion of the raw file how much DR you actually get.

One consideration of using the histogram that nobody seems to have mentioned is that the difference between film response and sensor response. I would be very wary of relying on histogram data when deciding on an exposure for film.


Film has maybe 5.

This depends on the film. At the low end is Velvia with only around 4.5 stops. Colour neg will give around 7 and B&W film around 10. I always carry some colour neg sheets in addition to my preferred Velvia as it's a life-saver when you need extra DR and grads are out of the question.

I do carry a digital compact when shooting with my LF kit but I only use it to try out alternative shots before setting up the heavy artillery. I wouldn't dream of using it as an exposure meter and if I need to check out a composition in 5x4 format, I use the tried-and-tested framing-card approach outlined above.

Joseph O'Neil
2-Apr-2008, 05:47
For metering I have found, at least in B&W, my Pentax spot meter works best. For colour, my hand held Seconic works best.

However I always drag a digital with me. Sometimes I shoot a scene first with digital to see what it looks like, and sometimes I see something I want to shoot but it isn't worth a sheet of film.

joe

Bob McCarthy
2-Apr-2008, 07:21
I would be very surprised if digitals actually had a usable DR that big. It all depends on careful conversion of the raw file how much DR you actually get.

One consideration of using the histogram that nobody seems to have mentioned is that the difference between film response and sensor response. I would be very wary of relying on histogram data when deciding on an exposure for film.



This depends on the film. At the low end is Velvia with only around 4.5 stops. Colour neg will give around 7 and B&W film around 10. I always carry some colour neg sheets in addition to my preferred Velvia as it's a life-saver when you need extra DR and grads are out of the question.

I do carry a digital compact when shooting with my LF kit but I only use it to try out alternative shots before setting up the heavy artillery. I wouldn't dream of using it as an exposure meter and if I need to check out a composition in 5x4 format, I use the tried-and-tested framing-card approach outlined above.

I have found the DR numbers to reflect my actual experience. The raw converters create very similar dynamic range output, Color, noise, blown highlight recovery, sharpness do vary somewhat between converters. Lord knows i've tested them all looking for the magic program, it doesn't exist.

As to color film, I was referring to transparency. I guess this is my bias.

And to the histogram comment. Correct sir, and the reason I was displeased with trying to use a digital camera as a meter. The histogram, doesn't match up with any film I use when predicting shadows or highlights. A calibrated histogram to a film would be the bomb, but it doesn't exist, certainly not within any digital camera I've used. In a roundabout way I thought this is what I was describing in the previous posts, I can see I was too obtuse...

No display on the back of any of my digital camera is large enough to substitute for a ground glass. But, some of the compacts do have largish displays and are possibly useful, I will conceed.

Bob

Marko
2-Apr-2008, 10:52
And to the histogram comment. Correct sir, and the reason I was displeased with trying to use a digital camera as a meter. The histogram, doesn't match up with any film I use when predicting shadows or highlights. A calibrated histogram to a film would be the bomb, but it doesn't exist, certainly not within any digital camera I've used.

A light meter inside a DSLR is very much the same as a stand-alone light meter. In both cases it is basically a photo-electric sensor that displays in one way or the other the intensity of the electrical current that the given amount of light generates. The manner in which that data is displayed is simply a matter of user interface. A histogram is, in a nutshell, a distribution curve of the signal strength across any given matrix of individual photocells that comprise the sensor. Any modern spotmeter could feature the same thing if equipped with an appropriate display and software/firmware, but all it would really accomplish would be to raise the price. DSLRs have it simply because they already have both the software and the display.

The question is not whether an electronic sensor could be calibrated to a film, the question is which film it should be calibrated to? And, at least in case of B&W films, which developer as well...

Just like with stand alone light meters, it is ultimately up to the photographer to interpret the data provided by a measuring device and translate that into desired tones and DR. With that in mind, which measuring device one uses is pretty much a matter of personal preference.

Bob McCarthy
2-Apr-2008, 12:30
I agree with the comment it is a meter, but it is not linear in the same way. The range left to right is not a standard quantity but an output that is matched up to the sensor, whatever the range of the sensor is. I suppose one could create a zone (ish) scale overlay over the rear lcd, by testing and trial and error. The middle of the range is not necessarily zone V, as most camera have bias in recommended exposure settings to protect highlight blowout.

If one didn't use the matrix meter and computer in the camera to determine exposure, and switched to the spot meter and calibrated the histogram, I suppose it would be usable.

BTW, the histogram is not raw data delivered from the meter, but a distribution of values from an internally generated JPEG processed in the camera with the thoughts of the manufacture built in to give the average user a high percentage of usable shots. That is far from just a light meter.

I tried to make it work, but settled on the reliability and sensibility of my Zone VI modified meter.

I might mention that I do believe in using a film camera as a meter. My F5 meters for slide film pretty darn well, but then the matrix meter was designed for the same film we use in LF.

Bob

timparkin
2-Apr-2008, 12:52
Although I don't use my digital for a light meter, I did play around with changing the jpg settings as they alter the histogram (good point for digital folk, always set your jpg settings to default or you'll get an incorrect raw histogram). I managed to get a good velvia replica by upping the contrast to maximim (on a 5D) and I also changed the preview to black and white to show intensity levels... It just didn't work for me as a way of understanding exposure though.. I bought a Sekonic 558 and didn't get on with this particularly either and then bought a Pentax Digital Spotmeter which is the bees knees :-)

Tim

Bob McCarthy
2-Apr-2008, 13:04
Let me suggest a simple test.

Put your digital on a tripod.

take 3 shots, one raw, one low iso jpeg, one high iso jpeg.

Look at the histograms. They will all be different. Sometimes a little, sometimes a lot depending on scene contrast range.

Same scene, same lighting, different histogram. The manufacturer is modifying the data in Jpeg processing.

roteague
2-Apr-2008, 13:08
I tried to make it work, but settled on the reliability and sensibility of my Zone VI modified meter.

I might mention that I do believe in using a film camera as a meter. My F5 meters for slide film pretty darn well, but then the matrix meter was designed for the same film we use in LF.

Bob

That is pretty well my conclusion as well. I sometimes use my Nikon F6 as a light meter; I've found my D200 has a tendency to underexpose everything too much. I will normally use the same film in both my LF and F6, and the matrix meter on the F6 is just fantastic.

I recently bought a Sekonic L-758D Digital Master light meter, however I'm having a bit of trouble getting used to using it - the view finder doesn't have the field of view my old Sekonic had.

Bob McCarthy
2-Apr-2008, 13:11
I managed to get a good velvia replica by upping the contrast to maximim (on a 5D) and I also changed the preview to black and white to show intensity levels...

Tim

Interesting approach. The downside of the histogram on many cameras, is its measuring luminance with the green channel only. For outdoor landscapes, you can imagine the bias. Not all cameras do this now, but it was the standard way. Pro cameras will output all three channels. It your histogram will output an rgb histogram, you' are seeing all three channels.

joolsb
2-Apr-2008, 13:36
Any modern spotmeter could feature the same thing if equipped with an appropriate display and software/firmware, but all it would really accomplish would be to raise the price.

Hardly. A spotmeter only takes readings of what it happens to be pointed at and an incident reading just reads an overall light level. What a histogram does is to represent the output of the many thousands of photosites of a digital sensor in a graph. It's an entirely different approach. Unless it was to work just like a digital camera, a handheld meter cannot produce a workable histogram, no matter how clever the software might be.

Marko
2-Apr-2008, 15:21
BTW, the histogram is not raw data delivered from the meter, but a distribution of values from an internally generated JPEG processed in the camera with the thoughts of the manufacture built in to give the average user a high percentage of usable shots. That is far from just a light meter.

Well, yes, a histogram is a distribution curve, I believe I said that much. It is not a light meter. But the light meter built into the camera is a light meter. My point was exactly that the two are not the same and that a correct interpretation is up to the user.

And I do agree that the linearity (whatever that really meant) is definitely not the same with digital sensors as it is with film.



I might mention that I do believe in using a film camera as a meter. My F5 meters for slide film pretty darn well, but then the matrix meter was designed for the same film we use in LF.

And again, the question is: which film?

I don't use slide film at all. I use negative film and then mostly B&W. Each of those has its own, very different response curve, which brings another question: in which developer?

Just to make myself clear, I am not suggesting that a DSLR is as good as a dedicated spot meter for this purpose, quite to the contrary. I use a Seconic 558 myself for LF, after all. What I am suggesting is that it is very much possible to use it that way, provided that one takes all the trouble of calibrating it to the film and developer one wants to use, just like it is normally done with regular spot meters.



Let me suggest a simple test.

Put your digital on a tripod.

take 3 shots, one raw, one low iso jpeg, one high iso jpeg.

Look at the histograms. They will all be different. Sometimes a little, sometimes a lot depending on scene contrast range.

Same scene, same lighting, different histogram. The manufacturer is modifying the data in Jpeg processing.

Yes, they do, they have to. JPEG is a format which utilizes variable compression, a lossy one at that. A file has to be processed in order to be compressed. That's one of the reasons RAW is so much better.

But again, a histogram is just a tool, the same as the camera that displays it. It does not do the thinking for us any more than a stand alone light meter does. It is the user who is supposed to interpret the data.

Bob McCarthy
2-Apr-2008, 15:52
Well, yes, a histogram is a distribution curve, I believe I said that much. It is not a light meter. But the light meter built into the camera is a light meter. My point was exactly that the two are not the same and that a correct interpretation is up to the user.

And I do agree that the linearity (whatever that really meant) is definitely not the same with digital sensors as it is with film.




And again, the question is: which film?

I don't use slide film at all. I use negative film and then mostly B&W. Each of those has its own, very different response curve, which brings another question: in which developer?

Just to make myself clear, I am not suggesting that a DSLR is as good as a dedicated spot meter for this purpose, quite to the contrary. I use a Seconic 558 myself for LF, after all. What I am suggesting is that it is very much possible to use it that way, provided that one takes all the trouble of calibrating it to the film and developer one wants to use, just like it is normally done with regular spot meters.




Yes, they do, they have to. JPEG is a format which utilizes variable compression, a lossy one at that. A file has to be processed in order to be compressed. That's one of the reasons RAW is so much better.

But again, a histogram is just a tool, the same as the camera that displays it. It does not do the thinking for us any more than a stand alone light meter does. It is the user who is supposed to interpret the data.

The problem is the manufacturers modify tones, not just compression. It has been found with digital, that over exposing reduces noise, so the whole exposure is shifted to the right as long as the highlights are not negatively impacted(blown out). So the scene determines the exposure not just the light. This is absolutely true with raw setting, lesser so with jpeg. There is a disconnect between the meter and the histogram displayed, modified by the manufacture to help the "great unwashed" get a high percentage of acceptable shots.

If you go to my first post, i mention that for B&W the digital sensor does fit better, but is not reliably accurate in my opinion. And as you point out, film type and pushing /pulling does modify the DR of the negative. Obviously the histogram could never accommodate this. I thought the poster who modified his jpeg setting to fit his slide film had a clever approach for that singular situation.

Your also right that I was only thinking in terms of transparency film, not color negative, in my post. Sorry for any confusion.

Bob

Joseph O'Neil
3-Apr-2008, 05:55
The problem is the manufacturers modify tones, not just compression. It has been found with digital, that over exposing reduces noise, so the whole exposure is shifted to the right as long as the highlights are not negatively impacted(blown out). So the scene determines the exposure not just the light. This is absolutely true with raw setting, lesser so with jpeg. There is a disconnect between the meter and the histogram displayed, modified by the manufacture to help the "great unwashed" get a high percentage of acceptable shots.
Bob

-snip-

I agree completely with you on that point. Just yesterday I was down to the local river (flooding - great shots :) ), and I had both my Tachi and my Nikon D40. How my D40 "saw" the light compared to my Pentax spot meter was two different things altogether.

So yes, while you can take time to calibrate your digital SLR to match your film, there are always occasions it will be out. Low light for example, as I find that even if you set the ISO on your DSLR the same as your film, at least in my D40, the CCD sensor is a lot more sensitive to low light than film, especially when you start getting into exposures of 1/2 or less. CCD chips do NOT suffer reciprocity failure. :D

I'm of the opinion if you forget your light meter, hey, use your DSLR for sure, better than nothing, but even thought I drag my DSLR with me when backpacking with my 4x5, I find from first hand experience, in may ways, pulling out the ole spot meter just works better in many ways

joe

Frank Petronio
3-Apr-2008, 06:55
I guess I am just a slob. I figure my dslr gets me within half a stop and keeps my highlights from burning out on my lab processed B&W... hardly Zone System perfection... but it works well enough for me.

I do concede that I'll pop a Polaroid from time to time just to "trust and verify".

Actually, about the only thing I ever worry about is not blowing the highlights -- everything else just falls where it falls.

(And yes, I used to do the whole Ansel Zone Pentax spot with N+ and N- development, etc.)

Edward McLaughlin
3-Apr-2008, 14:09
Again I have to say how impressed and grateful I am to all contributors.
I have learned so much from these wide ranging reports. Thanks very much.