juke

July 15, 2012

Hi,

The blurriness is in the film. It's visible in the negative/positive and also prints made in wet dark room using negative carrier with glass both side.

The Bronica was used by lot of photographers during film era, so if this is common problem, then somewhere should be references to it.

But I haven't seen any.

Some things that I haven't (still) investigated:

<ul>

<li>Could some film back allow too much curvature for film (usually wide field lenses suffer most from that)? This could explain why only some pictures have blurry corners.</li>

<li>Is it only my Bronica SQ-Ai body? Would any other body also give same result?</li>

<li>The size of image circle... How does focusing distance and/or used aperture affect to it?</li>

</ul>

January 6, 2010

Hi, I bought recently my first Flexaret. It seems working okay, except that I have problems with PC-sync. At the first, the flash didn't fire. My guess was that the PC socket was too loose. But after a while, I got my flash firing every time when I recocked the camera by using the second, multiple exposure cocking lever. Then every time when I tried to took real picture, the flash didn't fire :o It took a long time until I found one connection to the problem: The flash fires only when the lens is focused to 2 meter or longer distance. Anything closer than that does not give signal to PC socket. Is this a builtin feature or is it a fault? Anyone else encountered similar problem? Needles to say that it's pretty annoying when trying to shoot any kind of portrait photographs with a flash...

If it's a fault, then where should I look for the cause?

November 16, 2009

Still wondering with same issue. Does anyone have any photographs that illustrates how the rollers should be?

Google doesn't help much :(

October 24, 2009

Roger, I created the profiles with lprof and tested different versions, from rought profile to very exact. Nothing that could be seen in the results.

October 24, 2009

Yes that's exactly what I do. I scan using 'raw' output (gamma 1.0) which I have used for creating profile.

After a scan, I assign proper profile in photoshop and convert it to the working color space.

But where's the beef? I really don't get any better results with profiles than with scanning with fully automatic modes with various softwares.

Does anyone have simple examples of color slide scanned with calibrated process and then same slide scanned without any calibrations, just with the scanner's automatic levels & color settings?

If you will gain some advantage with calibrated scan, please show it. Where should I see it? The color balance - no. The contrast - no. Tonality - no...

Here's an example scans from 120 Provia 400.

The first is scanned with Vuescan's raw mode and proper profile assigment:

Here's same frame scanned with Epson's scanning software, no color management:

Then first scan (IT8-target calibrated) with auto tone applied to get rid of magenta color cast:

And the second one, Epson's "automatic" scan with autolevels applied in PS:

Really cannot say that the one from color managed process has any way better colors. It has a bit more contrast than epson scan's automatic result but it also has a magenta tint.

After simple adjustment in PS both looks quite same. The last one looks bit better to my eye.

I would expeced a lot more difference.

I got a bit suspicious for whole thing after I realized that same IT8 target in Faust's set is used for Velvia 100, Velvia 100F and Astia 100F films - and those films does not look similar in terms of saturation and colors on the lightbox. So why do they share same target?

October 23, 2009

Hi,

I had my previous scanner calibrated with WF's IT8-targets and I have go thru calibration process with my current scanners (V700 & Minolta sc IV) including three scanning softwares.

However, I have become more and more sceptic with the targets. They just don't seem to work correctly or I have completely misunderstood their purpose.

For example, I scan Fujichrome Astia with V700 using Vuescan - the output file will have gamma1.0 and I assign the proper profile in the photoshop.

That works well with the IT8 target and.... well, it works with any other color slide (astia, provia, sensia), but the color just aren't same as in original slide.

The black is not really black, the whole picture lacks kind a vividness. And usually there's more or less magenta color cast in entire scan (especially with astia and provia).

Now, correct if I am wrong, but I have understood that the purpose of IT8 target calibration is to get as good digital reproduction from the original color slide as possible. But it seems that the result is never any closer than just scan with fully automatic settings or scan RAW (or linear gamma, ..) and then correct all colors manually using curves tools.

Where did I got it all wrong?

August 30, 2009

Something to this old thread. Still a bit mystery.

I just re-read my old Adam's Negative (from 50's) and in that book the zone values goes from 0 to XI.

So when did zone X come to the terminology?

Zones are not equal with other's zones :)

June 25, 2009

Okay, the origins are there. Also found some information when browsing throuh my pile of books. In the book BTZS Davis writes that as industry standard for normal contast is 7 stops, same is used in this book and thus zones 0, I, {II, III, IV, V, VI, VII, VIII}, IX. With these the SBR range is "standard" 7 stops.

This is a pity. One has long used traditional numbering where IX is not pure paper white, but almost. Then some other photographers uses different scale, but still referring to ZS, some to BTZS.

When you usually can learn a lot of other photographers photographs if they tell to you about the exposure process. I put lightest part of her face on VIII and ... Then if another uses different scale, you are soon both lost. If photographer is follower of traditional numbering, then it is okay to put highlights to VIII, but if you as listener have most of the knowledge from BTZS etc. variants, you began to wonder that why did photographer put highlight so up?

As a side note, like I said, I have been always used full 0-X scale, but I have always been interested of sensitometric approach - but to get all of it, should use 0-IX scale, otherwise any other's results are not comparable with your's.

Or perhaps it would work if you standardise your normal as BTZS's N-1...

June 24, 2009

Hi,

I have to ask this dumb question. It has haunted me for years and haven't found answer even during recent 10 years of google.

I have originally learned ZS from adamses books, where IX is first barely distinguishable gray from pure paper white. However, there's a lot of literature referring IX as pure white and VIII as first distinguishable tone from pure white.

Where is the origin of this difference? And what is the reason behind it?

Is it from the Beyond The Zone System book, where a bit shorter SBR is used than Adams used?

Regards,

Jukka

February 1, 2009

I'll check the link, Tim.

Michael, I don't find any new 4990. But used 4990 are cheap when compared to v700.

February 1, 2009

Hi Alex,

Photo-i reviews give a lot of good information. The only thing that is really missing is comparison of shadow areas of the color slide film.

Unfortunately that is what I am looking for.

February 1, 2009

Hi, It is finally time to say good bye to my trusty old Epson 3200 flatbed scanner. But which scanner to buy now? Epson 4990 is quite cheap but old. Epson v700 is expensive but really good. v750 is out of budget. I have done <a href="http://jukkavuokko.com/public/epson3200vsV700/" target="_blank">quick test between my 3200 and v700</a> that I had access. The result is clear. v700 is way better than my old scanner. In both, sharpness and dense areas. My main need for scanner is to get MF and LF B&W negatives to web, which can be done perfectly with old 3200. The 3200 has dmax around 2.9 and typical negative has densest highlight somewhere around 1.8 I also have to scan all my MF color work for printing. This does not happen very often but this is where my 3200 really sucks. Actually I think that reason why I haven't done much color MF photography for couple of years is simple because I cannot get good scans from them. For LF, I don't even think color slides before I have decent scanner. Now I am asking have anyone done similar test between 4990 and v700/v750 that I have done between 3200 and v700. If such test exist, it would show clearly how much difference there is between 4990 and v700. I have google'd a lot. There are comparisons, but I have found a single one where dense areas are compared and shown. Usually the sample pictures are also so tiny that it's hard to judge anything. Thanks! Jukka

January 29, 2009

Hi,

This is a quite late reply. How are you doing with Hasemi?

I have Hasemi 4x5 wooden field camera and I like it. Only drawback is the bellows extension, which is limited only to 350mm. Thus longer lenses cannot be used.

Small, lightweight and beautiful!

January 26, 2009

Scanning and fine grain is always pain in the...

For traditional printing, the staining developers like Pyrocat-HD gives a smooths grain quite well and still give good acutance.

Scanning with blue channel helps.. At least I have found so. Here are samples (scanned at 3200dpi, scan dual IV), 100% crops. The subject of sample image is not perhaps the best possible but shows the difference in grain.

Scanned in RBG mode, then converted to grayscale<img src="http://jukkavuokko.com/linkatut/pnet/bw2008-40-0002%20CROP%20mv-scan%20shibuya%20girls.jpg" alt="" />

Same, but scanned in RGB and after scanning only blue channel is converted to monochrome: <img src="http://jukkavuokko.com/linkatut/pnet/bw2008-40-0002%20CROP%20shibuya%20girls.jpg" alt="" />

The film is Neopan 400, traditional fast B&W film. With TMY I would expect a lot of smaller grain.

It would be nice to know how staining developers compares to perceptol when acutance is important.

My opinion is that with staining developers, the result is better than with Rodinal. That is why I use staining developers so much in 35mm work.

January 23, 2009

One thing came to my mind. The image circle is smallest when lens is focused to infinity (and largest when focused to near). That could explain everything because at the edges of the image circle the image quality will always suffer.

There are still old page about the lens <a href="http://www.tamron.com/bronica/prod/sq40.asp">http://www.tamron.com/bronica/prod/sq40.asp</a> but there are only MTF curves, no any data about image circle.

Have to check if I can mount lens somehow to my view camera and then roughly measure the size of image circle!

January 23, 2009

Small update. I got nice example of edge sharpness of PS 40 in email.

After that I checked some of my photos and noticed that the blurry corners occures only at certain situations. I found many negatives where there is no remarkable blurryness at corners, even foreground of the image fills the corners of the negative.

Form the negative taken at f/16 I can enlarge 15"x15" print which has no problem with corners!

That makes me wonder why I have such problems often when there are distant objects near the corners? Even when I have focused lens to the infinity. That sounds quite similar with problems that Erlend Sæteren mentioned above.

ps. I will post examples of good corner sharpness soon.

January 23, 2009

Hi,

I did more testing with spreadsheet program. GNUplot requires too much work in windows environment which lacks all scripting tools for manipulating and generating data.

It seems that spreadsheet is enough for showing general shape of the curve. I am not going to deep with sensitometry. Another option could be use of spreadsheet for plotting coarse curve and then use drawing program with bezier curves for drawing smooth curve (which is quite closely my approach on paper).

The main things in my measurements are the speed point, zone VIII (and thus contrast). All other information is just for comparing quickly charasteristics of different films and/or developers and developer dilutions.

Which shape does toe have, is there shoulder on the curve?

That is information what I like to see from the curves. That is also the reason why curve smoothing is necessary. The measurements will always have error marginal, there can be also error within one measurement which is originated either from exposure, development or measuring phase. For such errors, the smooth curve is good.

The spreadsheet that I have used has one problem with smoother curves (trendline), it tends to emphasize curvature too much.

For example, here is one curve family as an attachment. As you can see, the N+1½ curve goes belove the N+1 curve at lower densities. However this is not the truth, in reality it is upper but trendline drawing algorithm has troubles with N+1 curve (as can be seen from it's shape).

About these curves: The developer I used is staining and densities are read with blue light. I have also made test exposures for finding speedpoint for my materials with this stain color. The speedpoint is quite accurate 0.09D above base+fog and really good visual VIII can obtained from density 1.35D above base+fog.

January 16, 2009

Thanks, I give GNUplot a chance!

January 15, 2009

Hi,

I have used plain old paper & pencil approach for drawing film characteristic curves and other sensitometry related figures.

Now I have finally will to try drawing with a computer. But with what software?

I have tried Excel, but it is not very suitable for task. The line smoothing (fitting) is not very good and it seems to be really complicated to use. No easy tools for measuring contrast indexes, zones, etc.

I know that there is BTZS software, but that is not exactly what I need.

What is your preferred software or are you still using paper and drawing curves by hand?

BR,

Jukka

January 6, 2009

That it is!

I am really sure that "zero" button's trigger is jammed or broken, so that it behaves like button is always pressed.

I tested by powering densitometer with "zero" button pressed, it behaved exactly like when I did same but without "zero" button.

Have to open and check the trigger and wires of the button.

Thank you really much! :)

January 2, 2009

Yes, the zero value will stay at the display. When I press the probe lever down, actual measurement "flashes" quickly and then zero comes back. However there is enough time to see reading, and occasionally reading will stay. This ofcourse gives the idea that one problem is probably defective in the trigger.

Then the problem with relative readings. I did what you suggested. Offset Null showed "1". Then I zeroed all channels while keeping lever down.

Now it should be zeroed and ready for measurements. OK, the first reading is fine. It is absolute density, however the next reading is difference to the that first reading.

For eg. If first reading (absolute value) was +0,14 and absolute value of second measurement is +0,17 then densitometer would show value +0,03.

If second measurement would give less density, then value is negative. If in the example above, absolute reading for second measurement would be +0,5 then densitometer would show value -0,09.

There is always either minus or plus sign. But according to the operator's manual, reading should be absolute, not relative. The relative readings should be get only when using memory and comparing values with ones stored to the memory.

Really weird.

December 28, 2008

Now I think that I understand why I have to take measurement without any target between each measurements. It seems that densitometer will show relative density change to previous reading each time when measurement is done.

Why is that, I don't know. The manual really does not help :(

The mode I use is the "Density", other options are "HD-LD" (don't know what this is) and "Offset Null density".

Here are the pictures of the densitometer:

December 3, 2008

Here are some photographs. I hope that it makes my question easier to understand :)

The 405 film back roller assembly, down side corner. The arrow shows the point where spring is pushing roll

down.

This illustrates scenario when 'print' is pulled between the rollers. Now the spring is really stiff and its

hard to pull even card that is used at the picture:

Finally the picture that shows the spring and roller axle when I have pushed small screwdriwer between the

rollers as an spacer. That illustrates how flexible the spring could be. But should it be?

Thanks,

Jukka

December 3, 2008

Hi, I have 405 film back. It's rollers are clean, but theyre really stiff.

If I try to pull tab to get picture out of holder, the tab will tear. The spring that pushes the other roller

downwards seems to be really stiff.

How stiff it should be? I can hardly push business card between the rollers, but often the card will bend.

Also I like to know whether there are some detailed pictures of 405 back's roller assembly available at the

internet.

Thanks for advance,

Jukka

November 30, 2008

I use Macbeth TR-944 densitometer (from year 1984). Before that I have used spotmeter as an densitometer and

even spotmeter of 135mm SLR camera with 50mm lens and closeup lens (see Phil Davis: Way Beyond The Zonesystem).

For a long time I also used scanner as densitometer. Just need to get RAW scan and use eyedropper tool at

photoshop or scanner software. Or preferrably densitometer functionality of the Vuescan scanning program.

You have only check the values given by scanner against real density values and then create correction curve.

I used stouffer's step wedge when created my correction curve.

The sample of curve for my epson p3200 scanner is attached to this message.

However I have been using sensitometric approach for a long time, I still don't think that densitometer is

necessary. You can get really good results without it. Even absolutely perfect, but for your developing system

and the enlarger you use.

The 'empirical' method is probably described somewhere at this board, but here it is at nutshell:

<ul>

<li> From a clear negative (only base fog), make test print using your most used enlargement size and use your

favourite paper and grade 2. Expose 20 or so steps to the test print.

Then after print is dry, evaluate it carefully. The last step which you cannot separate from black (ie. from

steps after it), will be your base exposure. The time that used for that step is the exposure time that should

create perfect work print.

<li> Figure out EI value for film. Make serie of negatives by exposing graycard and placing it to the zone I.

Bracked widely (at least 2 stops over exposure, use 1/3 EV steps).

<li> Develop the negative, print it with base exposure time you find earlier and then examine the print. The

right EI value is where you can barely see difference compared to pure black. This will be your zone I in the

prints always.

<li>Then do similar bracketing for zone IX and print the negative. If you can barely see difference with pure

paper white and zone IX graycard exposed using your EI, then you have N development!

If zone IX negative does not match with your EI, then modify developing time until it maches.

<li> Do same for N-1, N-2, N+1, N+2 :)

</ul>

By using approach described above, you will have really precise zone system. Without densitometer.

If you want 100% precise ZS calibration, then you must also do test for zone V, which should have exactly same

gray tone as gray card when compared each other. But that requires lot more work and result is way beyond what

you can get with any densitometer.

If you do that, then you will get print that represents exactly your previsualization, only by using your base

exposure time! However, thats exactly true only when using same enlarger and paper as used during calibration

So what is all that hassle with sensitometry and densitometers?

With densitometer you get values for somewhat near ideal. There negative probably would not print exactly as

you previsualised. It depends lot of your enlarger, paper and paper developer. That is why densities are given by

with great tolerance (for eg. V 0.65-0.75, VIII 1.25 - 1.35 for diffuse enlarger). The densities are only general

suggestions. When critical zones (V and VIII) are within these tolerances, then negative will be easy to print

even though enlargers, papers and paper developers varies.

Ofcourse, with densitometer you don't need to do test prints. It can save time... or not.

My personal opinion is that with empirical test print method with zone I and IX you get it all. I used that

for many years. The only reason why I like to use densitometer (and other devices before that) is that I am some

kind of number and film charasteric curve freak. I like to work with the sensitometry. As long as you need

only zone system for printing, you don't need densitometer. (Yeah, I know that I will be lynched now ;)

Regards, Jukka

Sign In

Profiles

Forums

Blogs

Events

Downloads

Gallery

Store

Posts posted by juke