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shootlarge
5-Jan-2012, 13:40
Greetings everyone!

I'm new to the world of LF and have been using this forum as a resource for a few months now. I'd like to start by taking a moment to thank all of you who continually develop and support the vast database that is the LF Forum. I stumbled upon this forum while reading camera reviews online a few months ago and can honestly say I have not needed to look elsewhere for any LF information since. Thanks to those of you who share your knowledge and experience, it makes learning this craft much more enjoyable for newbies like me!

That said, I just purchased my first LF camera after years of shooting with both medium format film and digital. I want to use the LF camera as a hobby and creative outlet to shoot landscapes and architecture. I've had the camera 2 weeks and I haven't bought a box of film yet so I've been practicing composing and focusing images in the mean time. I'm self taught, therefore not schooled in operating a LF camera, and have a few general questions pertaining to the setup and execution of my first shot. So here it goes:

1. When inserting the film holder, do I need to be worried about camera movement throwing my image out of focus? I'm being gentle in my practices thus far but my camera seems to move quite a bit no matter how gentle I load the holder. I would assume that any small movements would not be significant when shooting at f/11 or higher but what about wide open apertures?

2. What magnification loupe do you guys find to work best for a 4x5? I have a second hand Chamonix 045N-1 and I've been contemplating an 8x loupe, but I'd love to hear what is working for everyone else.

3. I bought a used lens with my camera, a Schneider Kreuznach Symmar-S 210mm 5.6 in a Copal No.1. Do I need to be concerned with dust particles within the lens elements? It is certainly not spotless inside and I've seen little specs in my images when shooting my Canon 5D at f/22 with a dirty sensor, don't want that effect on my LF images. Also, should I be testing my shutter to make sure it's calibrated correctly? I read a whole thread on this but it seems like a rather painstaking process.

I have countless other questions running thru my brain but these few seem sufficient for a first post, don't want to go crazy out of the gate! I apologize if these questions have been addressed elsewhere, I did a search and could not find the answers readily unburied. Thanks again to all who reply and I'm looking forward to many hours surfing the LF community's best resource! Happy New Year everyone.

-Chad

BTW, for those interested I started a blog that will document my journey into shooting LF. It should be rather colorful, honest, at times hilarious, and a good way to keep tabs on what I'm up to. I haven't taken a single photo yet, so try not to judge based on image content :) See signature for link.

John Rodriguez
5-Jan-2012, 13:59
1) Just make sure everything is locked down tight (camera controls, tripod head + legs).

2) Personal choice. I'm happy with my 5x, but it's all I've used.

3) Testing the shutter is a good idea and is actually very easy.

- Download Audacity (it's a free audio production application)
- Hopefully you have a computer with a built in microphone. Most new comps have them, if not, just buy a cheap one that plugs into the 3.5mm jack on your computer. My Macbook has a built in mic.
- Place the lens near the mic.
- Press record in Audacity
- Set the shutter for 1 second and release
- Stop the recording, then go look at the graphical sound wave representation and write down the shutter open and close times (obvious when you look at the screen).
- Repeat for each stop

Whole process only takes a few minutes

shootlarge
5-Jan-2012, 14:01
Thanks, John! I'll try that tonight.

cyrus
5-Jan-2012, 14:05
Hello and welcome to the madness!

1- If you tighten down the camera on the tripod and tighten down the movements on the camera itself, there should be no movement when inserting and removing the filmholder. Small movements may persist esp for old cameras/ tripods but that should not radically change your composition - if it does then something is broken and moving too much. Over time you'll get the hang of inserting and removing filmholders with minimal effort or stress on the camera.

2- Different people have different preferences - the answer is whatever works. I know a fellow who uses cheap reading glasses. 4x or 8x is standard. Too much magnification won't help anything. There's no need for a fancy loupe - a cheap pastic one works fine. Some loupes have a clear base or "skirt" -they don't work as well as loupes with an opaque skirt because they let outside light in. Some people prefer long loupes because, due to the construction of the camera, they can't really get their eyes up close to the ground glass (Calumet C1) so the loupe has to reach instead.

3- There is no need for a lens to be perfectly clean, and far more damage has been done to lenses by unneceesary attempts to clean them than anything else. You wont see the dust from a lens as you would dust on a digital camera sensor because dust on a sensor is basically at the focal plane. Dust particles and even bubbles in the glass are hardly rare things on LF lenses. If you've just bought a lens I guess a cleaning is in order anyway, but don't overdo it. Clean your lens once, keep your fingers and other icky things away from it (or use a UV filter as a cover) and keep the cap on when not working, and you should be fine for a long long time.

Testing shutters is fine but can be a pita requiring special gear for really accurate measurements

John Koehrer
5-Jan-2012, 14:39
loading the film holder shouldn't affect focus but will affect composition. The tripod head needs to be locked down. Depending on the head, it may not be possible with some older, lesser quality units.

IF the dust is between the front and rear groups, remove them from the shutter and clean 'em up. Just grab a group by the front and unscrew it. No tools needed.
If the dust is in a group, don't worry about it the light literally bends around them.

Errors in shutter speeds are within tolerance at +/-20% error. Between error in speed, timing of YOUR processing procedures, dev/fix, temp of the chems it's not likely that you're going to notice a difference. Same as you MF film.
It won't hurt anything if you want to test your shutter speed for your own curiosity but you're never going to get 100% accuracy.
Doing a film speed test to determine your personal EI is likely a more practical use of your time.
With any shutter, LF,MF or itsy-bitsy format, consistency is far more important. When you change lenses you may be changing your EI. So using the testing wold give an idea of whether there should be any correction needed.

ic-racer
5-Jan-2012, 16:10
Yes dust is a major problem. Film holders need to be kept free of dust and loading them needs to be done in a dust-free manner.

Jim Andrada
6-Jan-2012, 00:37
Depending on the camera of course, larger cameras sometimes have a mechanism to move the ground glass etc back without much force, then the film holder is easily placed in position and the back "closed" against it. Much less jiggling of the camera. My 5 x 7 is set up that way but older cameras usually aren't that sophisticated. I always try to stabilize the camera back with my left hand while inserting holders with the right hand.

Joe Wright
6-Jan-2012, 05:50
Hi Chad, welcome. Sounds like I'm only a few steps ahead of you so can empathise with some of the q's you are asking.

1) Not much more to add. Lock everything down tightly and the camera should settle back into place, and then when you pull the slide just let everything settle again before you fire the shutter, particularly when you are at long bellows extensions with the Chamonix. Also try not to introduce unnecesary instability into the setup, i.e. an unsupported big heavy lens hanging of the front.
2) I settled on 6x, suits the condition of my close vision. Very much a personal choice.
3) I might get round to testing my shutter timings one day, but as I very rarely shoot at a second or less, most of the time I'm on timer so any inaccuracy is down to my tolerance not the shutters!
"I haven't bought a box of film yet" - consider a box of cheap out dated stock to cut your teeth on, very little to lose that way...

gliderbee
7-Jan-2012, 02:47
This is a great trick ! I just tried it and now I have all confidence in my newly bought Kodak Ektar, apparently with Flash Supermatic shutter; times are right on (well, give or take a few hunderths of a second).

Edit: to read the result exactly, select with the mousepointer the part of the graph that represents the shutter noise; you can then read the exact time on the right.

Thanks !

Stefan.



3) Testing the shutter is a good idea and is actually very easy.

- Download Audacity (it's a free audio production application)
- Hopefully you have a computer with a built in microphone. Most new comps have them, if not, just buy a cheap one that plugs into the 3.5mm jack on your computer. My Macbook has a built in mic.
- Place the lens near the mic.
- Press record in Audacity
- Set the shutter for 1 second and release
- Stop the recording, then go look at the graphical sound wave representation and write down the shutter open and close times (obvious when you look at the screen).
- Repeat for each stop

Whole process only takes a few minutes

shootlarge
7-Jan-2012, 08:13
Thank you, John Rodriguez, for the trick! I spent about 15 mins last night testing my shutter at every speed and it turns out it's almost spot on! My largest degree of inaccuracy is at 1 sec where I'm 8/100 of a second fast. Other than that I'm nearly perfect at each. I'm pretty thrilled with those results, thanks for sharing your technique!

E. von Hoegh
7-Jan-2012, 08:17
Of course, the trouble with the Audacity test is that you are measuring the duration of the sounds the shutter makes, rather than the amount of time the blades are actually admitting light.

Not to rain on anyone's parade, but it isn't an accurate way to test a shutter except at the very slowest speeds.

gliderbee
7-Jan-2012, 09:28
Of course, the trouble with the Audacity test is that you are measuring the duration of the sounds the shutter makes, rather than the amount of time the blades are actually admitting light.

Not to rain on anyone's parade, but it isn't an accurate way to test a shutter except at the very slowest speeds.

The moment the blades are open, there's only the noise from the shutter itself.

If you first select the part where the noise is recorded, and then from the menu "zoom in on selection" (Ctr-E, I'm translating from the Dutch version), you can see very clearly where the blades snapped open, followed by a more or less continuous, low sound recording from the shutter, and then the blades snapping shut again.

Stefan.

E. von Hoegh
7-Jan-2012, 10:29
Sorry, but years ago I put a microphone on a shutter and watched the trace on an oscilloscope. Quite a lot happens soundwise leading up to the blades opening. The closing of the blades is cleaner. A shutter tester that measures the light coming through the shutter is really the only way to do it properly. As I pointed out, the Audacity program will only work accurately on the slowest speeds where the duration of the blades being open is several times as long as the other sound events.

Edit - Two people, posting above, have tested their shutters using this method. The results are that one shutter is 8% off at 1 sec, and "spot on" at all other speeds. The other shutter is good "within a few hundredths" at all speeds (if it's within afew hundredths at say 1/400, it isn't very good). I think this makes my point for me; I've tested shutters from brand-new to 100 years old. NONE, not one, was "spot on" at any but the slow speeds. My testing rig for leaf shutters uses a phototransistor and an oscilloscope with calibrated sweep. It is accurate to a few millionths of a second, according to frequency standards from NIST.

gliderbee
7-Jan-2012, 11:57
Well, you apparently know more about it then me, but still, I think it's useful to have an idea about the performance of the shutter; after all, I don't care if it's 1/400th or 1/405th (and that's what I meant with a "few hunderdths" off; I see now that I put it the wrong way :)).

Stefan.


Sorry, but years ago I put a microphone on a shutter and watched the trace on an oscilloscope. Quite a lot happens soundwise leading up to the blades opening. The closing of the blades is cleaner. A shutter tester that measures the light coming through the shutter is really the only way to do it properly. As I pointed out, the Audacity program will only work accurately on the slowest speeds where the duration of the blades being open is several times as long as the other sound events.

Edit - Two people, posting above, have tested their shutters using this method. The results are that one shutter is 8% off at 1 sec, and "spot on" at all other speeds. The other shutter is good "within a few hundredths" at all speeds (if it's within afew hundredths at say 1/400, it isn't very good). I think this makes my point for me; I've tested shutters from brand-new to 100 years old. NONE, not one, was "spot on" at any but the slow speeds. My testing rig for leaf shutters uses a phototransistor and an oscilloscope with calibrated sweep. It is accurate to a few millionths of a second, according to frequency standards from NIST.

John Rodriguez
7-Jan-2012, 17:00
Sorry, but years ago I put a microphone on a shutter and watched the trace on an oscilloscope. Quite a lot happens soundwise leading up to the blades opening. The closing of the blades is cleaner. A shutter tester that measures the light coming through the shutter is really the only way to do it properly. As I pointed out, the Audacity program will only work accurately on the slowest speeds where the duration of the blades being open is several times as long as the other sound events.

Edit - Two people, posting above, have tested their shutters using this method. The results are that one shutter is 8% off at 1 sec, and "spot on" at all other speeds. The other shutter is good "within a few hundredths" at all speeds (if it's within afew hundredths at say 1/400, it isn't very good). I think this makes my point for me; I've tested shutters from brand-new to 100 years old. NONE, not one, was "spot on" at any but the slow speeds. My testing rig for leaf shutters uses a phototransistor and an oscilloscope with calibrated sweep. It is accurate to a few millionths of a second, according to frequency standards from NIST.


When you're looking at the sound file it's very easy to see where open and close are when you zoom in. Your accuracy will be based on how many decimal points out you record the findings at. I've tested all of my shutters and none had 0% variance, but all were within 15%. I only test out to 1/60, as I rarely shoot faster than that and Audacity only zooms in on the file so far (I could use Logic instead but I'm too lazy).

What this won't tell you is whether or not your aperture settings are correct, for that yes, you'll need to measure the light. However, if you want a quick and dirty method to partially test your lens for free, this works.

Jim Jones
7-Jan-2012, 22:54
Accurate testing of my many shutters is one of those often postponed chores, but I'm with E. von Hoegh. Another often overlooked consideration is the aperture setting. At high shutter speeds the aperture can make a big difference due to reduced shutter efficiency.

E. von Hoegh
9-Jan-2012, 10:21
The Audacity test and similar tests are a kludge at best. Different shutters have different sound events. If you don't believe me, get a bunch of different shutters and look at the display. There's no traceable calibration for Audacity, either.


What we need is a reasonably priced and easy to use shutter tester.