Recommended Developers and Development Times for Konica IR 750

[pgwerner]

The other day, I was fortunate enough to pick up one of the last bricks of 35mm Konica IR

750 from my local photography store. I'd like to get some recommendations for a

developer for this film. As per my previous thread on Neopan Acros ( http://

www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00DIJ8 ), my priorities are sharpness

(the most optimal trade-off I can achieve between fine grain and high acutance) and good

tonal range. Since KIR is already kind of grainy, developing fine grain would be a priority,

but preferably not too much at the expense of acutance.

 

I'm thinking of going with Acutol, but have no reports on this film/developer combo.

 

Also, I'm looking for specific recommendations on dilutions, development times, and film

ratings. Usually, my attitude toward this kind of thing is that I'd rather do my own

experimentation, but the 14 rolls of KIR may be the last ones I ever have, it would be

wasteful to burn through them in an attempt to optimize my chemistry - hence I'm looking

for others' prior experience. I'll probably shoot one test roll to optimize exposure, but

then I'd prefer to save the rest for shooting some real photos. (I'm shooting with a Canon

Elan IIe, Tamron 17-35mm wide-angle zoom or Canon 50mm prime lens, and 89B IR

filter, if that information is helpful.)

[rustys pics]

Rate it at 64 with a #25 or #29 filter and develop in Rodinal 1:50 for 10 minutes. That worked for me.

[the shuttered eye]

<i>quote: "Rate it at 64 with a #25 or #29 filter and develop in Rodinal 1:50 for 10 minutes."</i><p>

If you are using a hand meter, would you then rate it as ASA 8 for the #25 filter (3 stops below ASA 64) and ASA 4 for a #29? <p>

Fainnly, are in-camera meters effective? Will the results be right if you just set your in-camera TTL meter to ASA 64 and meter with the filter on? I assume that in-camera meters (or hand meters, for that matter) don't meter infrared. I also assume that infrared varies by the time of year so that the proper exposure would vary as well. Is the only way to deal with this lots of testing and trials, and/or bracketing your exposures (probably a good idea, regardless)?

[pgwerner]

25 or 29? I'm not sure what filter rating system that is, but any idea if one of those is an

equivalent of a 89B?

 

I should point out that when shooting with an infrared filter, I typically meter first, *then*

put the filter on. Russ, I presume the 64 rating would be used *after* the filter is put on?

 

In answer to the question about metering for infrared light, no meter I know of does so,

but typically if you come up with an average value for the scene or take an incident or grey

card reading based on visible light and then compensate for the effect of the filter, you'll

get a good exposure. (Especially since IR filters don't completely block visible light, but

block enough of it so that IR comes through disproportionately - otherwise, IR would be

"swamped" by visible light.) Just don't meter off of vegetation or sky, which, I think, are the

only objects that are going to be hugely different in the amount of visible light vs infrared

that they reflect or transmit.

[kaiyen]

I rated the 120 variant at 30-50 or so with the filter _off_. That yields an EI of only 6 or so. I have seen other references to an EI around 12, again, with the red filter OFF. The film is pretty slow.

 

I developed in Rodinal 1+100 for 7:30. Grain with the bigger neg is very nice, but not sure that'll work so well with 135 film.

 

http://www.pbase.com/romosoho/image/43947480/medium

 

allan

[kaiyen]

Oops. it's a red 25 that I'm using.

 

allan

[rustys pics]

Filter rating system for #25 and #29 is the wratten one. Those are medium and dark red filters rather than the 89B, which is nearly opaque deep red.

 

I have used ISO 64 and even 100 with IR 750 in 35mm. Metering is TTL with an Olympus OM-1n. No need to remove the filter. Older TTL meters tend to be more sensitve to near IR light, and can give you a pretty decent guide to the ISO. Bracketing with IR film is always a good idea.

 

The 120 Konica IR was a very different animal. It seemed quite a bit slower than the 35mm version, and I rate that at ISO 12 and meter handheld. Same filters as above. You never quite know how much IR light is being reflected, so your mileage may vary, but those guides generally worked in bright sunlight, from 9am-4pm during summer.<div></div>

[the shuttered eye]

Most of what I have seen on the web (like the Massive Dev Chart) for processing times in Rodinal give the following for Konica IR 750 (exposed at ASA 50-64):<br>

Rodinal 1:50 at 68 degrees F for 5 minutes<br>

or 1:75 at 68 degrees for 9 minutes<br>

but I have also seen <br>1:50 at 68 degrees for 6.5 and 7 minutes<br>

In 2 books I have I see that following recommendations:<br>

1:50 at 70 degrees for 8.5 min (120 film) or 9.5 min (35mm film) -- from the Paduano book<br>

and<br>

1:50 at 68 degrees for 7 min<br>

1:75 at 70 degrees for 5 min -- from a book by Theresa Airey <br>

Russ' recommendation above is 1:50 for 10 min (at I assume 68 degrees). I am not challenging that recommendation. My question is, what should I expect to see differently at the different development times? For a given asa rating,what does increasing development time do -- does it make a uniformly more dense negative, or are shadow areas more affected than highlights? I have also read somewhere that Konica IR 750 tends to underexpose in the highlights -- has that been your experience?<br><br>

I realize I should do alot of testing and find out "what works for me", but I would like to find an optimal place to start. I just shot a 120 roll of IR 750 (and have a bunch of it in my freezer in both 35mm and 120 sizes) and have an unopened bottle of Rodinal sitting on the shelf. So I'm ready to give this a shot.<br><br>

 

Finally, I've seen some development times for Rodinal at the 1:100 dilution. Interestingly these times are shorter than the 1:75 or even the 1:50 dilution times. I see Rodinal 1:100 at 68 or 70 degrees for 4.5 - 5 minutes. Now I would have thought that increasing the dilution would increase development times, not shorten it. Is there anything about the Rodinal formulation that I am not understanding that might lead to this (that is, decreasing development time with increased dilution), or should I just dismiss these 1:100 dilution times as an error?

<br><br>

Thanks for all the help.

[kaiyen]

<p><I>For a given asa rating,what does increasing development time do -- does it make a uniformly more dense negative, or are shadow areas more affected than highlights?</I>

 

<P>I might be missing something but...just like with all B&W development, increased dev time increases the density of the highlights, not the shadows.

 

<p><i>Is there anything about the Rodinal formulation that I am not understanding that might lead to this (that is, decreasing development time with increased dilution), or should I just dismiss these 1:100 dilution times as an error?</I>

 

<p>I wouldn't dismiss them as error. First of all, I use 1+100 at 7:30, as I mentioned above. 4-5 minutes seems awfully short, unless it was a really, really bright day and it was all vegetation. Increasing dilution does generally increase development time. It does for me, anyway :-). I guess if you agitated like a martini you could get decreased dev time.

 

<p>I guess it's possible that what you're seeing is just the incredibly different times that result from the high IR contrast in many scenes. One person tends to shoot all vegetation on bright days, meaning there is some serious highlight action, and develops for 4 minutes to compensate. Someone else shoots street scenes and develops for 9 minutes.

 

<p>allan

[rustys pics]

Good questions about developing. Increased highlight density is usually the result of development. Increased shadow density results from more exposure. Infrared film is very idiosyncratic to the user. You'll have to do some testing to establish a working method. It might be good to shoot a roll and do clip tests at various times and developer dilutions from that same roll. That way, you can get more bang from a single roll.

[jordan_w.]

I set my camera's TTL meter to 32 *with* a Red #25 in front of the lens and developed in Rodinal 1+50. I reticulated the film badly, though. Use caution when processing it.

[25asa]

Anyone have any recommendations for ISO rating if dev'd in Xtol? And how long in Xtol straight? I am in the process of buying some recently expired stock of this film in 35mm and 120. I have a red filter, but am not sure what number it is. How much exposure compensation do you use when bracketting for this film?

[robert_grasing]

Peter, I'm curious about that 89B IR filter. Are you sure that's necessary? I've never seen any real difference between an orange and a red filter with Konica Infrared, let alone an IR filter, and I've been using this film since the early '80s. It does not have extended red sensitivity like the Kodak film, so I don't think you gain anything by using an IR filter. Why not try the IR, an ordinary red and an orange on your first roll, and compare?

[the shuttered eye]

The Massive Dev Chart (see: http://www.digitaltruth.com/devchart.html) says IR 750 (120 size) in Xtol 1:1 at 68 degrees F for 7.5 minutes.

 

Paduano book suggests for IR 750 rated at asa 50 using XTOL 1:1 at 68 degrees F for 6 minutes.

 

Elswhere I've seen XTOL 1:1 for 9, 9.5 and 10 minutes.

 

Also this earlier discussion on photo.net see: http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00BwOQ

 

As you can see, the range of times for XTOL is almost as wide ranging as for Rodinal. Take your pick, try it and the then adjust accordingly depending on your results. I suppose what all these differing recommendations means is that we really just have to find what works for us.

[nige_buddy]

I used to process it in Rodinal 1:100 for 18 minutes (agitation every 2mins). Negs printed nicely... I can't image what one of my negs processed for about 5mins would have looked like... very thin I'd imagine. I never metered, mostly over exposed the box recommendations of 1/60th @ f5.6 with a 25A (I used 1/30th). If I wanted a 'normal' pic, I'd meter (without filter) as 32asa.<div></div>

[pgwerner]

Robert -

 

Well, it depends on the strength of the "infrared effect" you want. You can shoot using a

Red #25, but the IR effect isn't as strong. There's a page here with comparisons:

 

http://www.pauck.de/marco/photo/infrared/comparison_of_films/

comparison_of_films.html

 

As for an 89B, I forget the exact wavelength where it starts to cut off most visible light, but

its below the 750 nm to which the KIR is sensitive.

 

Believe me, I looked into all of the issues of spectral sensitivity and Canon EOS

compatibility before I picked a filter and film to start doing IR work with. (It sucks that

Konica has discontinued this film. I can only hope that the new expensive but EOS-

compatible Maco IR film is as nice, since that's what I'll be stuck with when I use up my KIR

rolls.)

[robert_grasing]

Peter,

 

That's an interesting site. I've never tried an opaque IR filter with Konica IR. But I have a very deep red (but not opaque) filter that was designed for astrophotography with Tech Pan. With regular B&W, it cuts film speed by 5 to 6 stops. I'm now tempted to try it. OTOH, I only have 4 rolls of 120 and 1 roll of 35mm left. A little late in the game for experimentation.

 

It is a real shame about Konica IR. But I can tell you that the film departments of the large Tokyo camera stores, places that were once jammed and noisy with shoppers, pros buying baskets full of film, are now quiet and serene. The darkroom departments are nearly ghost towns and in some shops they have been pushed off into an unpopular corner. I used to have to wait in line to drop off or pick up my slide film, but now I'm often the only one there. I expect that Konica will soon eliminate its regular B&W films (they were never popular, even when film was king). Perhaps their slide film as well (AFAIK, I'm the only one in Japan who ever buys it). You have to wonder how long Kodak HIE will last.

 

Well, on that pleasant note, enjoy your IR film.

[rustys pics]

I have used MACO IR 850 and I like it. It's very slow, so should be an easy switch for us KONICA users. Allen, your IR photo of the Hill is well done. Are you sure it's a natural formation? It looks like an ancient mound structure like we have around St. Louis.<div></div>

[scott_walton2]

I have excellent results (shooting with a 25A) with D76 1:1 for 6 minutes @ 68 F degrees. It keeps the highlights down just a bit (so they aren't totally blown rendering base white) keeping any "hard work" down to a dull roar. With Infrared, the highlights won't really have alot of detail due to the nature of the wavelength anyway but you will have seperation in tones/paper base white.

[the shuttered eye]

Thought I would report back with some results from a test roll. A roll of 120 Konica IR 750 rated at ASA 50 and developed it in Rodinal 1:50 at about 69 degrees for 6 minutes. I used a #29 deep red Heliopan filter. I metered the scenes with a hand meter and then compensated from +3 to +5 stops (3 stop bracket in some cases). Even the shot with only +3 stop filter compensation was somewhat over exposed. The bright, August day might be responsible. The attached image was one of the images taken with just a 3 stop filter factor. Healthy adjustment using Curves in PS to deepen the lower tones so it looked reasonably right. Based on these results, +3 stops using the #29 filter seems about right in summer, might add additional exposure as we go into fall, and 5 minutes in Rodinal 1:50 might be enough development. (Shot with Mamiya 7II and 43mm lens).<div></div>