chris_jordan3

Hi again friends. I'm still having the double-image problem when making long exposures, and have eliminated the possibility that it's a bellows or pinhole issue. Others have mentioned having the same problem, suggesting that the film may be "popping" during my long exposures, due to being exposed to the air after being inside the film holder.

 

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I have another theory that I thought I'd run by you to see if it has any merit (any film manufacturing experts out there??). I've only had this problem when making long exposures, in dim light, with small apertures. So, what I'm wondering is, if there is some kind of internal reflection going on inside the film, that only becomes visible on the film when the light levels inside the camera are extremely low? What I'm thinking is that the image might be reflecting off one of the emulsion layers, or the back of the film. The double image is always just slightly offset from the "correct" image-- maybe 0.5 mm or so, and when using front rise it becomes more pronounced toward the bottom of the film (i.e., the image area that's furthest from the center of the lens, and the most susceptible to such a reflection).

 

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The reason I've come up with this is, my film is frequently exactly the same temperature as the ambient air because I backpack with my camera, so the "popping" issue likely doesn't apply. One morning I found what would have been an all-time killer image in the rainforest, and just to make dang sure I got one good original, I shot all of my film on the same image-- 16 sheets, and EVERY SINGLE ONE had the identical double image problem. My lens, bellows, lensboard, aperture, etc., are all pristine, and I always tap the film holder several times to lodge the film in place. I can't think of any other thing that it could be.

 

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Thoughts, similar teeth-gnashing experiences?

 

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~cj

hey friends, having pined for years over the frustratingly visible difference between prints made from 8x10 versus 4x5 originals-- even when printed in small size, i've decided it's finally time to make the jump. my 4x5 is a Wista SP-- totally bombproof metal camera that i have sworn by for a decade. I'd like to get something similar in 8x10 (i.e., not one of those bendy wood cameras), but it doesn't need to be backpackable-- just sturdy and reliable.

 

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any thoughts generally on issues I need to consider-- differences in the way 8x10 operates, equipment suggestions, etc? i've been shooting all these yars with a 210mm lens on my 4x5, so i'll probably get a 420 or something close to that range. i know depth of field is a big issue with 8x10, and of course weight and the cost of film-- any other things i should consider? general comments, suggestions, etc?

 

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thanks a bunch!

~chris jordan, Seattle

i do a lot of very low light view-camera work-- at night in dimly-lit

urban areas where my light meter gives me an exposure value of below 1

in the brightest areas of my images (requiring exposures in the

several-hour range). my trick is to bring a super bright flashlight

and shine it on my subject while focussing. i use one of those black

5-D-cell mag lights that's about as bright as a car headlight-- it

makes focussing much easier, and it doubles as a scarying looking

protective device when groups of drug dealers saunter by...

~chris jordan

p.s.: there are other sharpening engines out there other than

Photoshop's USM, but having done lots of testing with them the

consensus among the fine-art studios around the country is that

Photoshop's USM is still the best if properly applied using the

principles set out in my previous mesage.

~cj

hey guys-- there have been a couple of misstatements here about

sharpening that i wanted to help correct so you don't end up with bad

results.

 

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--first, NEVER use the sharpening algorithms that come with scanners.

they don't have the flexibility that Photoshop's USM has, and once

you've done it, you're stuck with it. make your scans with no

sharpening, and save them with no sharpening. sharpening is the VERY

LAST step to do before printing.

 

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--don't sharpen the image until you make a final print. do all of

your photoshop tweaks and save the file. then resize the image to the

print size, do your sharpening, and print it out. if you want to

save that file, save it as a different file, so the original

non-sharpened image will be available in the future so that if you

ever want to make a different sized print, you can resize it again and

sharpen it for that size.

 

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next, someone's suggestion here of using a high radius (i.e., 6

pixels) and low amount (i.e., 50) is a terrible way to sharpen. there

are lots of reasons why it degrades the quality of your image, but for

now i'll just say that top-notch printers who really know what they're

doing, never sharpen that way. among the fine-art photographic

printers there is some consensus on how to sharpen, which is to follow

these concepts:

 

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--do your sharpening ONLY while looking at the image in 100% mode

(actual pixels). if you look at it in "View print size" or anything

less than 100%, you will end up with an oversharpened image.

 

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--use a threshold of zero.

 

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--use a very low radius-- never more than 1 pixel, and usually in the

0.3 to 0.4 range.

 

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--because you're using a low radius, you will need a large "amount".

try starting with the amount at 300, and go from there based on how it

makes your image look. stay in 100% view mode!

 

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--after applying the unsharp mask, go to FADE, and fade it at 100%

(i.e., it doesn't fade at all), but put the fade in LUMINOSITY mode

instead of normal mode. what that does is turns the sharpening effect

into a black-and-white-only effect, so it doesn't increase the

saturation of the color of your image. this is a super important

step!! it accomplishes the same thing as converting to LAB and

sharpening only the L channel (but without doing the conversion, which

can degrade your image depending on what RGB colorspace you're in).

 

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--sharpen selectively in different areas of the image by making a copy

of the background layer and sharpening that, then painting the

sharpened areas selectively. that way you can sharpen some areas

more, other areas less, and for areas that are supposed to be blurry,

you can leave then unsharpened. you can even make several copies of

the background layer and sharpen each one differently, and paint

different areas from each one. this technique makes for a more

3-dimensional look and eliminates the creation of grain in smooth

areas where you don't want it.

 

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--another way to sharpen is to use the "sharpen" tool, which actually

is a fairly sophisticated tool. but it almost always oversharpens the

image, so after applying it, go to "FADE" and fade it back. stay in

100% view mode when doing this, and also put it in "LUMINOSITY" mode

instead of normal.

 

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okay, those are my nuggets for the day. happy printing.

 

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~chris jordan, Seattle

i've been doing exclusively night photography for years, frequently

exposing in the 2-3 hour range, and never shorter than about 4

minutes. i had my view camera for something like 3 years before i

finally used one of the shutter speeds on my shutter! unfortuantely i

frequently forget to bring a watch with me, and consequently end up

making wild guesses on exposures. once i had an exposure that required

18 minutes (including reciprocity failure) and i had forgotten my

watch so i just stood there and counted "one thousand one, one

thousand two..." for 18 minutes. just to be sure, i bracketed one at

40 minutes, which i didn't count-- just hung out for about 40 minutes

and clicked the shutter closed. and i gotback two transparencies,

both spot-on, that look like they're exposed about 1/4 of a stop

apart!

~cj

there's more to it than just scanning his 4x5's-- his images are

digital composites of many 4x5 originals. on location, he shoots

several images panorama-style, covering the entire location with

different images. then he scans each one and laces them all together

digitally to create a single seamless image that looks like it was

taken with a 20x24" camera using an impossibly perspective-controlled

ultra-wide angle lens. i don't know what the final filesizes are--

several 4x5's scanned at high res would pretty quickly get up into the

several-gigabyte size, and would approach Photoshop's max filesize of

30,000 x 30,000 pixels. perhaps he's using Live Picture or some other

program, or his scans are not as high-res as one would typically use

from a 4x5 (i.e., 300MB+).

~chris jordan, seattle

about 10 years ago i was photographing in a frozen meadow before dawn,

and while i was composing my Nikkor 210mm fogged and then the fog

froze into a sheet of ice on the front element. i had to take the

picture, but i had no lens paper or other cleaning stuff, so i wiped

the ice off using my dirty shirt knowing it would probably damage my

lens permanently. and, yep, it did-- took the coating off in a small

area and scratched the glass slightly. but i've been using it ever

since and it's sharp as tack, and the frozen meadow image is one of my

best so it was worth it!

~cj

one detail that supports the pinhole theory is that i only get the

ghost image when i'm using very small apertures. if i have a pinhole

problem then the ghost image probably just doesn't show up when

shooting at larger apertures because it doesn't have enough time to

expose the film. tonite i'm going to do some close examining with my

flashlight.

 

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another funny thing (which is why i thought others might have had this

problem): i was recently looking at a coffee table book of nature

shots, and i noticed that this one photographer's work all had the

same problem, but the images were printed in the book anyway. the

bottom half of every picture had the ghost image immediately

adjacent to the correct image, and the ghost image disappeared up

nearer the top half of the image-- just what i get. i wondered if it

is some internal reflection inside the film at extremely low light

levels but if that was the case, everyone who shoots with very long

exposures would have experienced the same problem.

hey all-- thanks so much for your thoughts. the pinhole concept is

the only one that i hadn't thought of, though (i've been wrangling

with this for a couple of years). my exposures are all long (10

minutes to 5 hours), and one time recently I shot thirteen sheets of

the same image and every one had the same ghost image problem. i've

eliminated any kind of movement as the source, because the ghost image

is identical every time, even after the camera has been in place for a

really long time and everything has had a chance to settle into place.

the ghost image does not show up on the ground glass (i've tested

with bright specular points of light), and i've also looked all around

inside and out of the bellows with a powerful flashlight in the dar--

no problems! what a conundrum. i think the only things it could be

are a problem with one of the elements of my lens being out of

alignment, or a pinhole on the lens board (improbably though-- it's a

wista metal board). i'll get both of those checked.

 

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by the way, what a cool group this is! i've been lurking for some

time; this is my first post. best regards to you all.

 

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chris jordan, seattle

(chrisjordanphoto.com)

I've been getting a double image on my 4x5 chromes when using the front rise on my Wista SP. The second image is only a couple of millimeters away from the first one, and it is more pronounced in some areas of the image than others. Any suggestions? Things I've checked so far: no problem with the bellows, and it's not the film moving inside the film holder during exposure (I tap them before inserting to make sure the film is solidly on the bottom of the holder). Possibly a lens problem? I use a Nikkor 210 W. Any help would be greatly appreciated.