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Need Guidance on Getting a Sensitometer
I have been reading the Kodak Basic Photographic Sensitometry Workbook H-740 and I think I am ready to start testing my film and developer combinations for creating a characteristic curve, determining D-min/D-max, Contrast Index, and exposure latitude.
I already have a solid process already in place with my densitometer where I can accurately determine the EI rating for any film and developer combo as well as the associated development times for N, N+, N-, etc. While it is possible to calculate effective film speed from the characteristic curve data, that is not in scope for me because of my existing process is very reliable.
My goal with the sensitometer in conjunction with the densitometer is to really compare same films in different developers and various films in the same developer to ultimately select the right films and developers that help me reach my personal creative vision.
While the exposure part can be done with an enlarger and electronic timer, a sensitometer just makes that part of the process fast, painless, and easy with 35mm roll film. I also think it is more consistent than using an enlarger too.
I would like to get a used sensitometer for testing B&W 35mm roll films.
Can someone with experience here in the group look at the available options on eBay and let me know what make and model sensitometer will work for testing black and white roll films?
I just want to make sure sensitometer that I get will allow me to create the characteristic curves as outlined in the Kodak workbook.
Thanks in advance for your help.
Larry
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Re: Need Guidance on Getting a Sensitometer
I’d get an X-Rite 301. Get the single button as it’s newer. If you look and take your time you should be able to get one for under $200. Make them an offer and Good luck
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Re: Need Guidance on Getting a Densitometer
I've been very happy with my Gretag D200-II and, IIRC, I paid something like $150 for it. And, it came with various size apertures, calibration strip, and dust cover all in the original hardshell case. I didn't have one for most of my photographic life, but it sure makes testing easier, more efficient, and IMO more accurate.
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Re: Need Guidance on Getting a Densitometer
If you want a new device, with a warranty and service, this is one of the best options: https://www.catlabs.info/product/heiland-densitometer
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Re: Need Guidance on Getting a Sensitometer
Hi Luis, I had a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
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Re: Need Guidance on Getting a Densitometer
Hi Alan, I have a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
Quote:
Originally Posted by
Alan9940
I've been very happy with my Gretag D200-II and, IIRC, I paid something like $150 for it. And, it came with various size apertures, calibration strip, and dust cover all in the original hardshell case. I didn't have one for most of my photographic life, but it sure makes testing easier, more efficient, and IMO more accurate.
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Re: Need Guidance on Getting a Densitometer
Hi, I feel embarrassed... I have a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite and Heiland densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
Quote:
Originally Posted by
koh303
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Re: Need Guidance on Getting a Densitometer
Quote:
Originally Posted by
LFLarry
Hi Alan, I have a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
Larry, the error was mine, not yours. I've reset the thread title accordingly, and I apologize for the embarrassment. I've also deleted your added apology from the initial post because you weren't responsible for the error.
FWIW, I can't recall reading about any still photographer using a sensitometer to expose film for these tests - it's always been a step tablet and/or carefully timed direct exposures to light. The methods Phil Davis describes in the various editions of "Beyond the Zone System" are par for the course. The only references I can find to sensitometers relate to use for X-ray and cine film process control in a commercial setting. I'm happy to be corrected if someone can point to documentation. Regardless, if you can lay your hands on one inexpensively enough, and can figure out how to check its calibration...
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Re: Need Guidance on Getting a Sensitometer
In the back of "The Art of Pyro" by Gordon Hutchings, are discussion and plans to build a "Zone Board".
Back in the day, I followed his lead, and constructed it as described. It did the job for me at the time, and I have just moved it to a permanent spot in my studio.
To read the zones and plot them, I used a vintage (Art Deco Bakelite) Kodak Visual Densitometer, which is surprising accurate and easy to use. I think I paid $40 for it long ago in a used camera store.
This stuff just works and is affordable
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Re: Need Guidance on Getting a Densitometer
And a follow-up: I've now read page 5 of that Kodak workbook and I see where this is coming from. Everyone I know who has done this procedure for themselves has made the required exposures simply by contact printing a step tablet under an enlarger.
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Re: Need Guidance on Getting a Densitometer
Hi, being new to this, I was thinking a sensitometer would simplify the exposure process of the step wedge by not having to expose a test wedge and then either use a lux meter or convert EV values to lux of the exposure light source to ultimately create the characteristic curves, etc.
I did find this interesting thread about various sensitometers used on B&W films:
Color of Light in Sensitometer Tests by IC-Racer
https://www.photrio.com/forum/thread...hootout.95837/
I was originally thinking about making an in camera 4x5 sheet film 21 step Stouffer step wedge exposure by placing the Stouffer wedge in front of a sheet of test film in the film holder and then setting the lens to infinity and exposing the film against at white board at +5 stops (Zone 10) in open shade at various EI ratings. I think I read about this on Paul Wainwright's website first. I have used this method for finding the true film speed of my film and developer combinations and for establishing N, N+ and N- development times, but never for plotting the 21 densities for the purpose of creating characteristic curves. Maybe that approach is valid, or there is a better approach using an enlarger maybe? Anyone here shed some light on this with your experience?
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Originally Posted by
Oren Grad
Larry, the error was mine, not yours. I've reset the thread title accordingly, and I apologize for the grief it caused you.
FWIW, I can't recall reading about any still photographer using a sensitometer to expose film for these tests - it's always been a step tablet and/or carefully timed direct exposures to light. The methods Phil Davis describes in the various editions of "Beyond the Zone System" are par for the course. The only references I can find to sensitometers relate to use for X-ray and cine film process control in a commercial setting. I'm happy to be corrected if someone can point to documentation. But if you can lay your hands on one inexpensively enough, and can figure out how to check its calibration...
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Re: Need Guidance on Getting a Densitometer
That seems to be the path that is most likely I think.
The one question I have is how would you know where to start with an exposure time using the enlarger light source for the step wedge contact exposure?
Would you do some trial and error exposure and development tests to find a test strip that has good tonal separation across the 21 steps or is there a better approach?
Also, this would have to be done in total darkroom since I would be exposing B&W panchromatic film.
Quote:
Originally Posted by
Oren Grad
And a follow-up: I've now read page 5 of that Kodak workbook and I see where this is coming from. Everyone I know who has done this procedure for themselves has made the required exposures simply by contact printing a step tablet under an enlarger.
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Re: Need Guidance on Getting a Densitometer
Quote:
Originally Posted by
LFLarry
Thanks for that link!
As you're figuring out what will work best for you, do take a look at "Beyond the Zone System" if you haven't already - the current edition is pricey but earlier editions are available inexpensively on AbeBooks. Phil described his procedures in detail.
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Re: Need Guidance on Getting a Sensitometer
https://live.staticflickr.com/65535/...13d405dd_z.jpgArt of Pyro Zone Board by Nokton48, on Flickr
Here is my homemade "Zone Board" as described and discussed in the back of "The Art of Pyro" by Gordon Hutchings.
From the top, Zone VIII, Zone VII, Zone VI, Zone V, Zone IV, and Zone III. As I recall that was really all the info you needed to plot.
Nice big references when you go to measure the negs.
I will be firing this back up soon, as I have time.
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Re: Need Guidance on Getting a Sensitometer
Oren, et al, here's another reference to using a sensitometer for film testing:
https://www.youtube.com/watch?v=VNbyShwYi6c
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Re: Need Guidance on Getting a Sensitometer
Quote:
Originally Posted by
Keith Pitman
Oren, et al, here's another reference to using a sensitometer for film testing...
Excellent, thank you!
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Re: Need Guidance on Getting a Densitometer
Thanks. I just purchased the kindle edition of BTZS and will check it out for more details that will likely help fill in the cracks.
Quote:
Originally Posted by
Oren Grad
Thanks for that link!
As you're figuring out what will work best for you, do take a look at "Beyond the Zone System" if you haven't already - the current edition is pricey but earlier editions are available inexpensively on AbeBooks. Phil described his procedures in detail.
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Re: Need Guidance on Getting a Sensitometer
Thanks Keith. I will watch it and see if it will help fill in some missing info for me. Have a good weekend.
Larry
Quote:
Originally Posted by
Keith Pitman
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Re: Need Guidance on Getting a Sensitometer
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Re: Need Guidance on Getting a Sensitometer
Hi Greg, really fantastic that you are producing these videos. I watched all 3 videos you have published so far and they are very well done. Great job!! Looking forward to watching the rest in this series.
Larry
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Originally Posted by
Greg Davis
That video is mine. I also have two videos following along with the Kodak Basic Sensitometry Workbook. Part 1 ( Exposing the step tablet and drawing the curves) is here:
https://youtu.be/eILVzTNWnq8, Part 2 (Calculating Gamma) is here:
https://youtu.be/OnhcX3x2YvU. I will get Part 3 (Contrast Index) up this weekend.
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Re: Need Guidance on Getting a Sensitometer
Very helpful for sure. Thank you!
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Originally Posted by
ic-racer
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Re: Need Guidance on Getting a Sensitometer
Hi, I want to make sure I am clear on a point that you made in the first link below.
Are you saying that the blue and green LED sensitometers that are readily available today which were designed for Radiographic work I believe are sufficient for testing B&W 35mm roll films for the range of sensitometry tests as outlined in Kodak's "Basic Photographic Sensitometry Workbook"?
Quote:
Originally Posted by
ic-racer
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Re: Need Guidance on Getting a Sensitometer
Quote:
Originally Posted by
LFLarry
Hi Luis, I had a typo in the title and in the original message. I meant to say "Need Guidance on Getting a Sensitometer". I guess I had densitometer on the brain. I have an X-Rite densitometer already, and now all I need is a Sensitometer for exposing the test films. Sorry about the typo and confusion.
If you want to test film for speed and developing time, I use a densitometer, NOT a sensitometer.
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Re: Need Guidance on Getting a Sensitometer
Hi Luis, I understand and agree with you. I am talking about using a sensitometer for creating a characteristic curve, determining D-min/D-max, Contrast Index, and exposure latitude. Basically, all the sensitometry "stuff". I have a solid process already in place with my densitometer only where I can accurately determine the EI rating for any film and developer combo as well as the associated development times for N, N+, N-, etc.
My goal with the sensitometer in conjunction with the densitometer is to really compare same films in different developers and various films in the same developer to ultimately meet my personal creative vision.
While the exposure part can be done with an enlarger and electronic timer, a sensitometer just makes that part of the process fast, painless, and easy with 35mm roll film. I also think it is more consistent than using an enlarger too.
Quote:
Originally Posted by
Luis-F-S
If you want to test film for speed and developing time, I use a densitometer, NOT a sensitometer.
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Re: Need Guidance on Getting a Sensitometer
I don't know of any consumer-grade sensitometers being made today. When I worked for Eastman Kodak, my division designed, built, and sold a few of the Model 1-B sensitometer. It was used to characterize aerial camera and duplicating films, and create control strips for the various specialized processes used. I believe we supplied a few 1-Bs to other Kodak divisions, as well as the U.S. government. It was also about the size of a home washer-drier combo, and the price must have been quite substantial (as in if you have to ask...). Of course if you're a manufacturer selling hundreds of million dollars worth of quality product, you'd need something like that. Oddly enough, my first assignment at EK, in 1984, was to make photographs of that machine for an upgraded instruction manual.
I'll guess that any of the various home-made devices mentioned above will serve your purposes quite well.
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Re: Need Guidance on Getting a Sensitometer
I have no idea if these are worth buying, but there are 50 FS
I think they were used for Mammogram X-Ray which was the last of the analog uses in NA
https://www.ebay.com/sch/i.html?_fro...R+SENSITOMETER
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Re: Need Guidance on Getting a Sensitometer
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Re: Need Guidance on Getting a Sensitometer
Quote:
Originally Posted by
LFLarry
Hi, I want to make sure I am clear on a point that you made in the first link below.
Are you saying that the blue and green LED sensitometers that are readily available today which were designed for Radiographic work I believe are sufficient for testing B&W 35mm roll films for the range of sensitometry tests as outlined in Kodak's "Basic Photographic Sensitometry Workbook"?
LED sensitometers work fine for comparative testing most black and white panchromatic films. Analogy is a 'balance' where you have to place objects on both dishes to compare things.
Attachment 207535
Attachment 207536
Attachment 207537
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Re: Need Guidance on Getting a Sensitometer
Just watched it Greg. I gave it a thumbs up and commented and posted a question for you too (Stealth Van Life is my YouTube handle).
Quote:
Originally Posted by
Greg Davis
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Re: Need Guidance on Getting a Sensitometer
Randy, the issue with the X-Rite densitometers is they don't publish the exposure time or the illuminance value of the light source, both of which are needed to build characteristic curves. Based on the info from IC-Race, the Blue & Green LED units will work for B/W film exposure. I wonder if the exposure time and illumination value is provided with the calibration data?
Quote:
Originally Posted by
Tin Can
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Re: Need Guidance on Getting a Sensitometer
Hi Greg, the way that I read IC-Racer's tests on the LED Blue/Green Sensitometer's via the Photrio threads was that they performed properly for him in regards to the full range of tests and validated across multiple films and developers. I assume he had to figure out exposure time and illumination or he could not have constructed the characteristic curves. It would be good for IC-Racer to comment on this specific thread for clarity.
I am a novice at this, so I may be missing something or possibly misunderstanding?
Quote:
Originally Posted by
Greg Davis
The blue and green X-ray sensitometers will be useful for comparing different films, but may not be full spectrum enough for contrast index, accurate film speed, etc. And they may not have a means of measuring illuminance. There are three EG&G units on ebay right now that are 5500K flash units and discussed in IC-racers threads on Photrio. They may need work on the electronics though.
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Re: Need Guidance on Getting a Sensitometer
Hi, did you see Greg's comment about this earlier in the thread?
With being a novice at sensitometry, I am trying to make sure I am clear on these issues so I can go buy a unit that not only works, but will perform across the full ranges of tests.
Here was Greg's earlier comment: "The blue and green X-ray sensitometers will be useful for comparing different films, but may not be full spectrum enough for contrast index, accurate film speed, etc. And they may not have a means of measuring illuminance. There are three EG&G units on ebay right now that are 5500K flash units and discussed in IC-racers threads on Photrio. They may need work on the electronics though."
Thoughts on this based on your tests?
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Originally Posted by
ic-racer
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Re: Need Guidance on Getting a Sensitometer
Did you read the manual I posted?
Here it is again
https://www.xritephoto.com/documents..._Manual_en.pdf
Quote:
Originally Posted by
LFLarry
Randy, the issue with the X-Rite densitometers is they don't publish the exposure time or the illuminance value of the light source, both of which are needed to build characteristic curves. Based on the info from IC-Race, the Blue & Green LED units will work for B/W film exposure. I wonder if the exposure time and illumination value is provided with the calibration data?
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Re: Need Guidance on Getting a Sensitometer
I have not tested the response of Fomapan but I'd probably use the Blue LED to compare it to the other films for speed. In terms of making processing control strips to monitor development, the color should not matter per graph 1.
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Re: Need Guidance on Getting a Sensitometer
Hi, yes, I did read the manual, twice actually, and I even searched the PDF as well to ensure I didn't miss anything.
I can't find anywhere in the manual where it specifies the exposure time or the illumination value of the light source for any of their units. I even went and looked at other X-Rite units and nothing there as well.
I also read the full list of specifications and nothing there as well.
If I am overlooking something, please point me to the page please.
Quote:
Originally Posted by
Tin Can
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Re: Need Guidance on Getting a Sensitometer
I just bought on eBay a matching set X-RITE 331C DENSITOMETER AND X-RITE 383 SENSITOMETER
and read both manuals for them online before buying
The manuals say it is useful for Cine and X-Ray B&W film
So 2 new toys incoming, both guaranteed to work from a high rated seller of other things, who took my offer
At least they are not huge like some of my LF adventures
Perhaps useful with my pile of old films and the still in date
Another question may be, does anybody compare frozen film to new?
I am a complete no nothing about this gear, but do enjoy trying new things
Quote:
Originally Posted by
LFLarry
Hi, yes, I did read the manual, twice actually, and I even searched the PDF as well to ensure I didn't miss anything.
I can't find anywhere in the manual where it specifies the exposure time or the illumination value of the light source for any of their units. I even went and looked at other X-Rite units and nothing there as well.
I also read the full list of specifications and nothing there as well.
If I am overlooking something, please point me to the page please.
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Re: Need Guidance on Getting a Sensitometer
Quote:
Originally Posted by
Tin Can
I just bought on eBay a matching set X-RITE 331C DENSITOMETER AND X-RITE 383 SENSITOMETER
and read both manuals for them online before buying
The manuals say it is useful for Cine and X-Ray B&W film
So 2 new toys incoming, both guaranteed to work from a high rated seller of other things, who took my offer
At least they are not huge like some of my LF adventures
Perhaps useful with my pile of old films and the still in date
Another question may be, does anybody compare frozen film to new?
I am a complete no nothing about this gear, but do enjoy trying new things
Great pickup.
What I do is to test all my 'working' film/developer combinations for baseline. Then, when some "unknown to me" film or developer comes along I can compare the new stuff to the known stuff in the comfort my darkroom (with the sensitometer/densitometer) before going outside to do the in-camera tests.
https://www.largeformatphotography.i...light=shanghai
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Re: Need Guidance on Getting a Sensitometer
I have been busy, but just tested the 1996 X-RITE 331C DENSITOMETER in like new condition, all documentation included with the very handy AC charger adapter Looks like original rechargeable batteries
First null or zero unit, push a button labeled NULL !
Then using the original included step wedge with OE calibration readings from 1996 in ink pen, my reading today match
Next to check if X-RITE 383 SENSITOMETER works, which is less a concern as I have a Stouffer Step wedge and could burn my my own
All made in USA
Quote:
Originally Posted by
ic-racer
Great pickup.
What I do is to test all my 'working' film/developer combinations for baseline. Then, when some "unknown to me" film or developer comes along I can compare the new stuff to the known stuff
in the comfort my darkroom (with the sensitometer/densitometer) before going outside to do the in-camera tests.
https://www.largeformatphotography.i...light=shanghai
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Re: Need Guidance on Getting a Sensitometer
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Re: Need Guidance on Getting a Sensitometer
Quote:
Next to check if X-RITE 383 SENSITOMETER works, which is less a concern as I have a Stouffer Step wedge and could burn my my own
To plot the results from the sensitometer, you will need to know the values of the step wedge. Is it built-in to the 383? If so you will need to remove it to measure it with your densitometer. I had to do that with my EISCO and Wejex. The EG&G does not have a built-in step wedge. You can use any step wedge you have on the film stage.
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Re: Need Guidance on Getting a Sensitometer
Found this in old thread
Download it now, before the end...
Basic Photographic Sensitometry by Kodak 2006
https://www.kodak.com/uploadedfiles/...y_workbook.pdf
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Re: Need Guidance on Getting a Sensitometer
If using that workbook (everyone should read it), it assumes you will know the output of the sensitometer. One can find that, using the principle in post #42 above.
By definition the exposure to produce 0.1 density on a H&D curve for ISO 100 film will always be 8.0 millilux seconds.
Since Logs let us add and subtract, we can change that to the Log of 8 which is 0.9, now that can be subtracted from sensitometer light intensity in log units.
Log of Light Source millulux seconds = 0.9 (by definition for 100 film) + Step Wedge Density that produced 0.1 on the film.
So if you plotted Ilford Delta 100 and find which step of the step wedge in your sensitometer gave you the 0.1.
Say it is step 6, so you have already disassembled the sensitometer and measured step six and got a step wedge density of 2.0
Sensitomter Log Millilux seconds = 0.9 + 2.0 = 2.9 = 800 millilux-seconds
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Re: Need Guidance on Getting a Sensitometer
I'm not sure if the original responder really wants a sensitometer,or a densitometer.
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Re: Need Guidance on Getting a Sensitometer
Sensitometer. Confirmed with PM.
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Re: Need Guidance on Getting a Sensitometer
Wow fun thread. Use a sensitometer to find things out about fresh film: your development time. The test you do that results in an ASA parameter match, with fresh film in a standard developer, logically gives you (by trusting the manufacturer) the amount of light which struck the film. So when you meet the parameters then you have calibrated the sensitometer.
Then when you test an unknown film in an unknown developer. I have a roll of 1940’s Super-XX that was nominally 200 (100 old ASA but 200 new ASA). It would have been 200 at the time but depending on fog (If I develop in D-76 1:1), or if I add Benzotriazole to the developer), I expect it to test out as 50 or 100.
The “speed point of a 200 speed film will shift to the right on my graph one stop (0.3 log units) compared to TRI-X, but since the film is unknown due to age, it may shift significantly more.
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Re: Need Guidance on Getting a Sensitometer
Bill, you have solidified my thoughts on how to use my new gear
This is all new to me and I am an old dog
Thank you!
Set my own standard with new film, then compare and contrast is my understanding
Quote:
Originally Posted by
Bill Burk
Wow fun thread. Use a sensitometer to find things out about fresh film: your development time. The test you do that results in an ASA parameter match, with fresh film in a standard developer, logically gives you (by trusting the manufacturer) the amount of light which struck the film. So when you meet the parameters then you have calibrated the sensitometer.
Then when you test an unknown film in an unknown developer. I have a roll of 1940’s Super-XX that was nominally 200 (100 old ASA but 200 new ASA). It would have been 200 at the time but depending on fog (If I develop in D-76 1:1), or if I add Benzotriazole to the developer), I expect it to test out as 50 or 100.
The “speed point of a 200 speed film will shift to the right on my graph one stop (0.3 log units) compared to TRI-X, but since the film is unknown due to age, it may shift significantly more.
