Is this just over exposed...

steveo_mcg

steveo_mcg

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Steven
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... or do I have other problems?

I've been meditating (not really) on my Hooley'd shot yesterday and trying to decide if its just seriously over exposed and I'm miscalculating my reciprocal adjustment, the meter reading is bad in the first place or if I've got other problems.

The camera is a coffee tin with a hole in the end, the pinhole is cut into a bit of coke can and taped to the bottom and the film is secured to the lid, so far so standard. I've not had a chance to paint the inside black yet, tbh I can't be bother to strip it and repaint as I don't think spray paint will stick to the current finish.

(ignore the artefacts etc the jpg has compressed really badly! I'll get a better copy later but you get the idea)


2013-10-apx400-om30047-jpg.539
 
Is this a scan of a negative or are you using reversal paper in the camera?

My first thought is it is massively underexposed, but what was the subject? Was it a night scene? What should be there?

David
 
foggy ? ( not the weather )
 
This is scene. My meter read F8 - 1/15 and according to my calculations thats about a minute at F230, add in recipirical failure and we're about 6 minutes. From what I've read FP4+ is t^1.48 and GP3, apparently, responds in a similar manner.

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I was worried I'd fogged it but I'm not sure how as I was very careful loading it in the bag. There was a little bit sticking out the tin but I doubt that would cause the whole frame to fog.
 
My calculator says that your exposure time should have been 7 mins.
 
So not over exposed then? Well assuming the meter was reading correctly. 1 minute at that lenght of exposure wouldn't have made such a difference, would it?
 
It would be easier to judge the negative if you took a picture of it against a light table ( or a computer monitor set to a white screen) and included some of the screen around the negative. For reducing reflection inside the tin I often use black craft paper and double sided tape to line the inside.
 
looks to be a recipricol issue to me steveo.
 
Just come across this:

http://mkaz.com/photo/tools/reciprocity.html

if you metered incorectly by a stop and needed nearer 2 mins as against one then with recipricol failure, you would be looking in the region of 17 minutes exposure!!

Much as one minute with a long exposure may make little difference, I'm pretty sure 11 mins will.

I realise this info is based for moonlit photography but as far as i'm aware the recipricol adjustment will be the same for the film regardless of the source of light.
 
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Yikes! Yeah that might be the issue. Looks like that was the last time I'll get a chance to shoot it for the next few days but next time I'll take a better meter and a copy of a recipricol chart and hopefully make a better negative!

One more thing though, the negative is virtually black, wouldn't that mean it was overexposed?
 
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Yes a black neg equates to overexposure......getrs more confusing dunnit?:confused::D

It could well be a mixture of more than one issue Steveo.

Perhaps look at lining the tin as David suggests to reduce reflection and re assess the metering/ recipricol adjustment .

Go for it my man..... Practice practice practice, go round in circles, collapse in a stuper, then give up.:lol:

I'm sure you'll sort it .......eventually!:D

Good luck :thumbs:
 
Have you considered duffing the development up?
 
steveo_mcg said:
One more thing though, the negative is virtually black, wouldn't that mean it was overexposed?
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- If the negative is black then yes it is overexposed/overdeveloped/fogged - your pinhole may be bigger than you thought / check your dev concentration, temperature, time/ black out inside of tin. It is hard to tell things from scans of negatives as the scanner tries to adjust things - hence why taking a photo of neg against an white light source helps. One thought did you use a normal scanner or one for film that shines light through the negative?
 
Asha said:
Go for it my man..... Practice practice practice, go round in circles, collapse in a stuper, then give up.:lol:

Good luck :thumbs:
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It might have been easier to start with a modifed roll film camera rather than a coffee tin but where is fun in that!

robhooley167 said:
Have you considered duffing the development up?
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Not on purpose do you think it would help :D.

That might be a good shout actually, my rodinal was starting to look a little like overbrewed tea so maybe time to open the new bottle.


dmb said:
- If the negative is black then yes it is overexposed/overdeveloped/fogged - your pinhole may be bigger than you thought / check your dev concentration, temperature, time/ black out inside of tin. It is hard to tell things from scans of negatives as the scanner tries to adjust things - hence why taking a photo of neg against an white light source helps. One thought did you use a normal scanner or one for film that shines light through the negative?
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Good adivce, I'm pretty confident on the pinhole size as I had some micro drills which I used as a guage. There isn't much to see on the negative, it needs to be held up to a halogen to see the image. Yup scanned with my trusty V500.
 
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Tired Rodinal would tend to underdevelop - my homemade Parodinol (headache tablets, drain cleaner and wine bottle steriliser) is two years old and looks like builders tea but still going strong. I would tend to look at trying to measure the actual size of your pin hole as a first step - got access to a microscope ?
 
No microscope but I could scan it and measure in photoshop.
Its theorectially between 0.45 and 0.5 mm as the .45 bit will fit through but the .5mm will not even if it is as much as 0.55mm then it would only be 1:30 over exposed which is only 25% over and I wouldn't expect it to be this extreme.

Oh and Parodinol? Sounds interesting.
 
What's the focal lenght of your camera?
 
Looking at http://www.mrpinhole.com/calcpinh.php and makiing some guestimates for the size of your tin - f230 not far out. But scene photo looks like a f/11 at 1/60th for 125ISO which is a good 3 stops brighter than you metered (if conditions were the same) so base exposure time on 13 seconds rather than a minute - that would give a much shorter time than 6 mins allowing for reciprocity failure - http://pinholery-blog.zonev.de/?p=72 has some numbers for GP3 reciprocity and a formula - I work that out to 42 seconds e^(1.46*ln(13)+0)

Sheesh thats enough maths before lunch for me. Good luck

I based exposure time on three stops below Sunny 16 from Pinhole calculator which gives 1.65 seconds at f/230 so 8*1.65 = 13 ish but should only have been two stops - duh 7.5 seconds - so 18 seconds by formula
 
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Reciprocity gives me a head ache! Looks like I'll need to use the good meter next time. Thanks David, so really was just grossly over exposed.

I'll make the other adjustments suggested and load her up and hope for a bit of sun one lunch time and try again. God help me when I try these ancient glass plates.
 
The Pinhole designer program that can be downloaded from here http://www.pinhole.cz/en/pinholedesigner/ will do all the exposure calculations for you, for most of the well known films.

If we accept that you are 2 stops out in your initial exposure reading then for FP4+ the calculator gives an adjusted exposure time of 47s.
 
Yeah thats what I've got from my calculations, 5 full minutes is a hell of an overexposure.
 
Right attempt numero tres.

Over exposed again, this time because my phones timer stopped as soon as I put it in my pocket so I only checked once I got bored... But there is an image!

I think the sun might have been hitting it at an angle judging by the left of the frame and the right is a little dark because I lost my grip on the shutter half way through so there was a bit of black card blocking the frame for a few moments. I didn't have a chance to cover the insides so that probably hasn't helped with the contrast. Little bit of camera shake due to trying to hand hold for the better part of a minute too. Moving in the right direction at least!

I think I'm going to park this for the time being, I've bought a Noon from a chap in the classifieds so some roll film will give a chance to experiment and get to grips with the exposure times.


Pinhole GP3-3 by steveo_mcg, on Flickr
 
Gave the first one 10 minutes in light room and its clear I do have other problems but I think they're related to GP3 being curly as hell.

pinhole-gp3-2-jpg.620
 
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steveo_mcg said:
Right attempt numero tres.

Over exposed again, this time because my phones timer stopped as soon as I put it in my pocket so I only checked once I got bored... But there is an image!

I think the sun might have been hitting it at an angle judging by the left of the frame and the right is a little dark because I lost my grip on the shutter half way through so there was a bit of black card blocking the frame for a few moments. I didn't have a chance to cover the insides so that probably hasn't helped with the contrast. Little bit of camera shake due to trying to hand hold for the better part of a minute too. Moving in the right direction at least!

I think I'm going to park this for the time being, I've bought a Noon from a chap in the classifieds so some roll film will give a chance to experiment and get to grips with the exposure times.


Pinhole GP3-3 by steveo_mcg, on Flickr
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Well done Steveo for battling onward with this.....without a doubt you look to be heading in the right direction.
The Noon is probably just what you need along with possibly some film with a recipricol failure easier to calculate/ shoot with.

I reckon you'll get to grips quite quick re exposure times etc etc and obtain some good results from a purpose manufactured pinhole camera......from there I'd hope you return to this coffee tin version armoured with knowledge and hopefully attain similar quality pinhole shots.

Best of luck!
 
Asha said:
Well done Steveo for battling onward with this.....without a doubt you look to be heading in the right direction.
The Noon is probably just what you need along with possibly some film with a recipricol failure easier to calculate/ shoot with.

I reckon you'll get to grips quite quick re exposure times etc etc and obtain some good results from a purpose manufactured pinhole camera......from there I'd hope you return to this coffee tin version armoured with knowledge and hopefully attain similar quality pinhole shots.

Best of luck!
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Cheers Asha, It was probably a little optimistic to try a self build for a first attempt. I'll get this lined and try again once I've had a bit more experience, then to see if can get anything recorded on my glass plates.
 
I'm now on roll three in the noon. My tally so far, two skipped frames, one accidental double exposure, one film stated at 3 instead of 2 thus losing a frame and one film that didn't wind tightly and has hopefully only fogged the edges. These problems before I've even worried about developing anything!
 
steveo_mcg said:
I'm now on roll three in the noon. My tally so far, two skipped frames, one accidental double exposure, one film stated at 3 instead of 2 thus losing a frame and one film that didn't wind tightly and has hopefully only fogged the edges. These problems before I've even worried about developing anything!
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I'm assuming it's 120 film.....how many frames do you get to a roll?.....seems not many:shrug:
 
Asha said:
I'm assuming it's 120 film.....how many frames do you get to a roll?.....seems not many:shrug:
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Yeah 120, you can add baffles to shoot 6x6 or 6x9 but what's the point in that! :-D. I've been shooting with 6x12 so I only get 6 so over winding a frame is a bit of a b****r...

Just souped the Fp4 from today. Light leaks on all frames, one looks OK, another isn't bad but has some frame numbers showing.
Most of the frames have shine through from the backing paper probably from the sun rather than the red window. But most of the frames are black. Irritatingly the double exposure look like it might have been interesting.
 
Sounds like your having nothing but fun!! :lol:

If light is getting in by whatever method, pick up a dark cloth cover of some description .....doesn't necessarily have to be a purpose cloth for photography so long as it blocks out light and it will cover the camera. i have to incorporate this idea with many cameras, particuarly folders that have leaky backs or bellows and others that if left in bright light for too long, allow light to creep in through the red window.

Doesn't always keep em light tight but it does dramatically reduse the entry and allows em to be used.
 
I'm pretty confident that the leaks are solely down to the roll not being tightly wound. On the other hand the exposures don't look bad, confirms the nikon fg meter is working OK too, I had to use that because I forgot a separate one. If I'd realised how badly wound it was I'd have waited until I got home.
 
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