Shanghai GP3

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Athiril

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Just wanted to post this here, a lot of people write of Shanghai GP3, but I've always enjoyed it, I just totally forgot about since I started shooting other films more.. think I might buy a lot more of this now.. haven't shot it for ages and made a recent order from China with EMS shipping to test to check if express packages from China get xrayed, no xray fogging.

Processed in Xtol replenished (24 degrees, 5m 45s). Flextight 949 scanned 3200 dpi (6x7cm), much finer grained than I remember. Only scan adjustments are levels to maximum black and white levels. No sharpening.

This is fresh GP3 too, dated 2016. Shot at box speed (100). Mamiya RB67 with 90mm Sekor C.


2dj7395.jpg


3200 dpi crop
1xxs7d.jpg
 
I have used twelve rolls of GP3 in 120 and it is an adequate film, though the base is a bit thin. The problem isn't the film but the backing paper - if the film is not very new, or is too warm, or is ever a bit damp, or the wind is in the wrong direction(?), then the frame numbers transfer from the backing to the emulsion. And this seems very unpredictable. Grrrrr.
 
I've shot a fair bit a long time ago and never had that issue once, I always got mine straight from HK or China over eBay. Even if I left it sitting around for a long time.

It must be really old (other people's stuff) when they have that issue. I do prewash mine though as well.
 
I pretty consistently have damage from the backing paper - I think it's emulsion adhering to the paper as it comes out dark in the print/positive scan and must therefore be lighter on the negative.

Check the bonnet (hood) of the car:

See no evil... by Scrambler@4350, on Flickr

It LOOKS superficially like a problem with the lettering but in fact it's all over the film with small grain-like patches. It's just more obvious with the lettering.

I do live in Australia, the weather does get fairly warm, but honestly this frustrates me. I get it with apparently fresh GP3 as well - it's not simply an "expired film" issue.

I haven't tried processes to minimse the time I have it - I only started reading up on the problem recently, having assumed that previous problems were a dud batch. I don't recall having the trouble with my first purchase of GP3 - back when it was in red paper.

And logically I can't see how prewash would do anything, but I will try it just in case. I have three rolls shot in the last 2 days set aside for testing.
 
I bought 10 rolls last year and the first two came out fine. Then I don't know what happened, the quality just went worse and worse. Started to get the dreaded backing paper lettering, and some weird texture also. Could it be from the texture of the backing paper? Anyway, I told myself I'm never touching this stuff again!
 
It doesn't makes sense to buy it in single units. I purchased 20 and it took one year or so. After eight months I can't read numbers as good as it was at beginning. Same cameras.
The price difference is insignificant comparing to some more reputable brands.
I don't think I'll buy another 20 of it.

In Rodinal.

6x6x2 by Ko.Fe., on Flickr

x-tol.


Untitled by Ko.Fe., on Flickr
 
I also live in Australia, used to live in North Coast NSW when I used this stuff a lot. I've had texture/patterned stuff on the film once. It was when I decided to see how hard I could push the film. Trying to push beyond 400, that one roll had it, no numbers though.
 
Shanghai GP3 benefits a lot from good presoaking. The artifacts you get from the backing paper are due to the antihalation dye that somehow reacts with the paper leaving residuals of it at the end of development.
A good presoak to get all that bluish dye away solves this problem.
 
Nikos72 said:
Shanghai GP3 benefits a lot from good presoaking. The artifacts you get from the backing paper are due to the antihalation dye that somehow reacts with the paper leaving residuals of it at the end of development.
A good presoak to get all that bluish dye away solves this problem.
Click to expand...

wow, cool info!
I always presoak 120 .. that's why I never had that. (I shot around 12 rolls so far)
 
Nikos72 said:
Shanghai GP3 benefits a lot from good presoaking. The artifacts you get from the backing paper are due to the antihalation dye that somehow reacts with the paper leaving residuals of it at the end of development.
A good presoak to get all that bluish dye away solves this problem.
Click to expand...

Thanks! That is good info. The frame numbers on my gp3 negatives are getting way to arty farty.
 
Not a bad film at all. Only issue as far as I can see is black backing paper and white numbering is almost impossible to see when using red-window type cameras. On auto type cameras however, it is a joy to use. I like it in Caffenol:


Hard Rock Cafe by Eirik0304, on Flickr


Stump by Eirik0304, on Flickr
 
Yeap, the longest the presoak goes, the less dye remains and less funky stuff appears on your developed film later.
 
Anyone presoak and use diafine? I think I read somewhere that there is a speed loss from presoaking and the effective film speed drops to ISO 40?
 
Nikos72 said:
Shanghai GP3 benefits a lot from good presoaking. The artifacts you get from the backing paper are due to the antihalation dye that somehow reacts with the paper leaving residuals of it at the end of development.
A good presoak to get all that bluish dye away solves this problem.
Click to expand...
Wow very interesting, I'll have to try that one day. I usually do presoak, but only for a few minutes. maybe that's not long enough!
 
Put to the test - and I don't know what to make of it. Will need to more %*^% testing!

First roll: 1 hour presoak, rinse, another hour, rinse twice, then develop.

Shanghai GP3: worst yet by Scrambler@4350, on Flickr

Next roll, no rinsing or soaking, just straight into developing:

Shanghai GP3 unwashed by Scrambler@4350, on Flickr

Third roll, 30 minutges presoak, rince once, develop:

Shanghai GP3 short wash by Scrambler@4350, on Flickr

All these were exposed within minutes and then developed 2 days later, within minutes of each other. The second roll had been respooled to 620 and shot in a folding Brownie, the other two shot in an Ensign Auto-Range 220.

All films have been stored together at room temperature. Rolls 1 and 3 were fresh from the box when shot, roll 2 had been loaded for about a week.

I only just realised that my "brick" of 20 had 2 expiry dates: 5/2015 and 8/2015. I don't know which the test rolls came from, so back to the drawing board!

At least I can say with confidence that washing does not prevent the problem and not washing doesn't cause it.

Note - purely test photos - they are not to demonstrate anything other than the effects (or lack of effects) of different approaches to preventing Shanghai GPox
 
My batch was a 2014 one, all 4 with the same dates. The first one without pre-soak came out with imprints from the backing paper on the glossy side. The second one with a 3 minute presoak had such artifacts but considerably less. The third one with three 1 minute presoaks came out clean without any marks.
Form your test I tend to believe that the marks are not on the glossy side on the film, but on the emulsion side which proves that these films have more production issues.
I am really tempted to get a few more for the price, but what if that one in a million smile of my son comes out with funky stuff all over it?
Seems to be some sort of gamble over here.
 
Interesting. i have never pre washed and never had these problems, there is quite a discussion on flckr about GP3 and the problems with backing paper and frame numbers. I do believe that the 2013 expiry rolls i used where better than the 2014 rolls i have at the moment. It is a nice film but quality issues obviously exit - thats ok, matches my skill level..
 
Thanks scrambler for the tests. My presoak was about a minute with agitation in the middle of that, not very long at all, no second rinse, just presoak then dev.

Perhaps take note of the emulsion number perhaps for any bad rolls (they're below the expiry date).

I might roll up some of the backing paper with some scrap film and put it into developer together and see if it reacts and does something to the film.
 
All my current rolls are emulsion 5102, for both expiry dates. For my next test I'm going to develop unexposed rolls of both dates.

The marks are definitely on the emulsion side and are visible clearly on unexposed parts.
 
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