Holga WPC exposure time seems too long..Test shots added!

Asha

Asha

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Asha
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holga120wpc.jpg

Shot at 2012-08-20

I'm a little puzzled as to why the exposure times listed on the back of this camera are so long...perhaps someone can enlighten me?

From the info i have found and from my own calculations the aperture equates to approx F/135

By my reckoning, based on sunny F/16 ruling a 100 iso film would demand an exposure time of 0.5 second at F/128 so theoretically darmned as near (fractionally longer!) the same for F/135.

This being the case, why is it that the exposure guide on the rear of the camera states 7 - 9 seconds in fine weather?.....that is one huge difference!!

Tbh I'm unsure wether to believe the guide or not as to me it isn't logical not even with recipricol failure built in, which wouldn't become an issue until an exposure of approx 1 second and beyond was needed.

I wish to go and play with my new toy but don't wish to waste a roll of film nor my time and effort in the process.....
 
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happygolucky said:
Just had a quick google and found this::

http://www.brokenaperture.com/?tag=holga-120-wpc

I know nothing about your camera, but I hope this may be of some help.
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Thanks for the link.....seems the author was a little puzzled like I am:


QUOTE:
"On the back of the camera, you have an exposure guide. It gives you three options for exposure times. So far, the sunny one is pretty accurate, though I would exposure perhaps for just a little bit longer myself, and compare the results. Previously, I had compared results from a light meter, and a pinhole exposure calculator. The calculator figured I should expose for 1/4 second, vs. Holga’s recommendation of 7-9 seconds. Huge discrepancy, and Holga’s claims seem to be closer to accurate. So I am going to look into this a bit more and find out why, when the calculators work for other people without flaw…"

Shame there is no update on what if anything he found out!

I know of at least two members who frequent f&c who have pinhole cameras, one whom owns the very same camera.....i'm sure some advice will come my way when they see this thread ;)
 
I am not sure, but it could be that you are dealing with a Holga pinhole camera and not a camera that is fitted with a lens with good glass like anything else :).
 
medwaygreen said:
I am not sure, but it could be that you are dealing with a Holga pinhole camera and not a camera that is fitted with a lens with good glass like anything else :).
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Mmmmm perhaps!........... I have no idea how the lack of glass would have an effect on the exposure time, but if that is the case then I would like to learn more about it..............as you can tell I'm not up on pinholes!:D
 
Thats what I thought, Not sure then why it being a holga vs some other homebrew solution would make any difference. I think the only solution will be to waste a roll and see what happens.
 
steveo_mcg said:
Thats what I thought, Not sure then why it being a holga vs some other homebrew solution would make any difference. I think the only solution will be to waste a roll and see what happens.
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Well i could take it for a play this afternoon and try a mix of exposure times varying from my calculations through to Holgas recommendation....would have prefered to get all the shots exposed something like decent...Oh well here goes nothing.........Heads off to search out a cheapo roll of 120 from the fridge!
 
srichards said:
This is someone else's attempts at working out an exposure table. Worth trying theirs, yours and holgas to see which works...

http://www.flickr.com/photos/mrwhitemanphotos/5727896394/

I don't think there is any substitute for experimentation unfortunately :)
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Thanks for the link...looks to have come up with a similar result to my calculations....as you say it looks like an experiment of differing times is going to be the only way.
 
sweetlime said:
If you have a light meter then using that alongside a calculator like http://www.mrpinhole.com/exposure.php?Fstop=135 seems like the most accurate way?
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Pretty similar to the chart Suz lead me too ......

Thanks for your help folks.......I'm going to head out with a roll of Fomapan 100 and try a selection of times.......I'll post some results in due course, assuming of course i get any!! lol
 
Asha said:
Pretty similar to the chart Suz lead me too ......

Thanks for your help folks.......I'm going to head out with a roll of Fomapan 100 and try a selection of times.......I'll post some results in due course, assuming of course i get any!! lol
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Just a quick note, Fomapan has the worst reciprocity of any film i've ever used so this test might not be too conclusive
 
Good luck.

Though from a cursory look round I don't think many people are using the Holgas chart so might be better going with your gut... On the other hand you know faaar better than me so I'm going to shut up.
 
robhooley167 said:
Just a quick note, Fomapan has the worst reciprocity of any film i've ever used so this test might not be too conclusive
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Ah....I've just loaded it ....you got me wondering now is it worth changing it before I go out....could use Adox 100, Ilford Pan 50...got some HP5+ and Rollei RPX but they're 400 iso!
 
steveo_mcg said:
Good luck.

Though from a cursory look round I don't think many people are using the Holgas chart so might be better going with your gut... On the other hand you know faaar better than me so I'm going to shut up.
Click to expand...

At this rate it's gunna be "good luck" that gets me a result! :lol:

Where on earth do you get the idea that I know faaar more than yourself?.....I look the part but in reality i just blunder my way through!!!!:D :D :D
 
:lol: :D

Next +1 project I think is going to be a pin hole but first want to get a half decent folder.
 
Asha... from a fellow WPC User - ignore the "guesses" on the back of the camera, either use your calculations or the ones above...

for my part - I just used 100iso film and gave it 6 elephants if I could see my shadow on the ground, and 10-20 depending on how gloomy the sky looked when I couldn't (or adjusted accordingly when I shot with filters for B&W). It's a Holga, and a Pinhole, and half the time you'll screw up and either only half advance the film, or wind it on twice, or forget to remove the lens cap anyway so why sweat it. I think out of maybe 10 rolls through the camera, I can't think of a single roll where I managed a clean 6 shots!

(did manage to get the OCCASIONAL half decent image here and there though)


Lighthouse by The Big Yin, on Flickr


Delta100_2011-02-03_003.jpg by The Big Yin, on Flickr

and one that I like, even though I don't really know why...


Barlow Common by The Big Yin, on Flickr
 
:D thanks Mark....I screw up with most cameras i use somewhere along the line!

Well I kept the Fomapan loaded and headed out but only got one shot (due to a lack of inspiration of what to shoot) which I shot "half way" between Holgas guide and my own calculations seeing as I couldn't decide which to go for.

I may get out tomorrow for another play and wander a bit further afield.

If I get anything like your lighthouse shot i'll be well pleased and very proud.


TheBigYin said:
Asha... from a fellow WPC User - ignore the "guesses" on the back of the camera, either use your calculations or the ones above...

for my part - I just used 100iso film and gave it 6 elephants if I could see my shadow on the ground, and 10-20 depending on how gloomy the sky looked when I couldn't (or adjusted accordingly when I shot with filters for B&W). It's a Holga, and a Pinhole, and half the time you'll screw up and either only half advance the film, or wind it on twice, or forget to remove the lens cap anyway so why sweat it. I think out of maybe 10 rolls through the camera, I can't think of a single roll where I managed a clean 6 shots!

(did manage to get the OCCASIONAL half decent image here and there though)


Lighthouse by The Big Yin, on Flickr


Delta100_2011-02-03_003.jpg by The Big Yin, on Flickr

and one that I like, even though I don't really know why...


Barlow Common by The Big Yin, on Flickr
Click to expand...
 
As promised here are some results.
Exposure wise, these are "as shot" ...they have only been reframed and sharpened slightly in pp.

1. Shot at 4 seconds.... half way between my calculations (2 seconds) and Holgas recommendations (8 seconds). Exposed somewhere near OK given the sharp contrasts.

6holgasharpenedanddustr.jpg

Shot at 2012-08-28

2. Shot using my own calculations (0.5 - 1 second)...IMO is exposed near on correct.

1holgasharpenedanddustr.jpg

Shot at 2012-08-28

3. Shot half way between my calculations and Holgas recommendation (4 seconds)...Over exposed
2holgasharpenedanddustr.jpg

Shot at 2012-08-28


4. Shot at Holgas recommendation ( 8 seconds) ....forgot to wind film on so there is a 2 second double exposure on this shot, however regardless of that the shot is still massively over exposed.

3holgasharpenedanddustr.jpg

Shot at 2012-08-28

5. Shot using my calcuations (2 seconds) Again with the sharp contrasts the exposure is not so far out

4holgasharpenedanddustr.jpg

Shot at 2012-08-28

6. Shot using Holgas recommendations (8 seconds) Over exposed in places....An exposure time of approx 4 seconds would have possibly been ideal

5holgasharpenedanddustr.jpg

Shot at 2012-08-28

Conclusion: The times recommended by Holga appear to be far too long. having said that, I am sometimes dealing with an EV of 16 or 17 ( very occasionally 18 on highly reflective surfaces) light levels in the summer which I believe considerably brighter than the UK.....I am guessing the times indicated on the back of the camera would work pretty much ok in a less bright country and that is what Holga has based the times on!

My own calculations appear to have worked out pretty much ok I think although perhaps a fraction longer is optimal.

Either way i managed to get results and now have a basis on which to work on for future films.
 
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Nice results. By the way if you find the mechanical vignetting distracting you can widen the plastic hole to get rid of it, which I did to mine.
 
Thanks Wilson....Tbh I'm happy enough with the results i got too.....The vignetting doesn't bother me too much atm but I have taken note of your suggestion should it begin to get on my wick!..............These were taken 6 x 12..........is the vignetting similar when using the 6 x 9 adaptor??
 
Top two of my shots were full frame on 6x9 adaptor, no faffing around in PP reducing the vignette... the long tall one was done after gently "countersinking" the plastic hole (for want of a better term) Didn't open the back of the hole per-se, just the front of it in a gentle taper.

that being said, having had a look at the raw scans from my first roll, It doesn't appear that my camera was anywhere near as pronounced a vignetting as yours did - but hey - that's holgas for you. Not what you'd call consistent manufacturing from sample to sample.
 
TheBigYin said:
Top two of my shots were full frame on 6x9 adaptor, no faffing around in PP reducing the vignette... the long tall one was done after gently "countersinking" the plastic hole (for want of a better term) Didn't open the back of the hole per-se, just the front of it in a gentle taper.
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Wished I tried your method first, I just used brute force and pushed a pen through it until I thought it was big enough. It was too big that I had patch it with card to stop light leaking. :bang:
 
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