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atorger
29-Feb-2012, 04:59
I'm currently in the looking-around-phase, moving to "large format" digital (really cropped medium format, 36x48mm). Linhof Techno seems like a good platform in that case, and can start off with 6x7 MF film before I get my paws on a good second hand MFDB deal. Anyway I have not operated a large format camera before so I'm a complete newbie and try to gather as lot of information as possible in advance.

Electronic shutters are very expensive, say $1800 per lens or so, so I'd rather use the much cheaper Copal shutters. Less weight and no batteries is a plus too.

With a digital back, it would be nice to do HDR and stitching and other composite images in some situations. What I wonder is if that is doable with a manual shutter, or if you need so much force changing settings and cocking that it is hard not to disturb the camera position when operating the shutter between shots. I know there are self-cocking shutters, but I don't think time is much of a problem (3-4 seconds between shots is ok), and I still would need to change shutter speed.

Say a workflow like this:
1. set shutter speed to 1/400, cock shutter, take a shot
2. set shutter speed to 1/100, cock shutter, take a shot
3. set shutter speed to 1/25, cock shutter, take a shot

That is taking a HDR-series of shots in fairly quick succession without disturbing the camera too much.

I've never operated a copal shutter in my hands, just some ancient compur shutter which is quite tough to change shutter speed -- you need quite a lot of force. I'm hoping that a modern copal shutter has a bit smoother controls...

What do you think? Can you work (reasonably) fast and do "multi shots" with a copal shutter without disturbing the camera? Or would you need an extremely heavy camera that sits in place regardless how much force you need for operating the shutter controls?

B.S.Kumar
29-Feb-2012, 05:22
I have both Copal and Prontor Professional shutters, and do multiple exposures all the time. Changing shutter speeds is not a problem on either type. Modern Copal shutters require very little force to cock the shutter, but there is an undeniable risk of movement in the process. With the Prontors, the risk is far less.

Kumar

welly
29-Feb-2012, 05:38
I shot two frames in moderately quick succession this evening and lining up the two negatives, aside from the exposure, they're both lined up perfectly. Cocking the shutter in a copal shutter takes absolutely no effort at all.

Erik Larsen
29-Feb-2012, 06:52
You might try a copal press shutter which is self cocking but the Max shutter speed is 1/125 I believe. You still have to worry about moving the camera while changing the speed, but don't have to worry about cocking the shutter.
Regards
Erik

atorger
29-Feb-2012, 07:23
Thanks for the replies. I think I will be ok. There's always some risk of movement, but it is probably going to be so small that there is no problem to solve it with alignment tools in post-processing. I was kind of more worried of setting the shutter speed for HDR, since on this old shutter I tried it was quite tough to turn the dial. Cocking it was smooth.

Preston
29-Feb-2012, 09:22
After setting the shutter, cocking it and removing the darkslide, I wait for a few seconds before pushing the release. This gives any vibrations I may have induced time to damp out. Pushing the button on the release smoothly helps minimze vibration, too.

The key is to have a set procedure, and to work deliberately and smoothly.

--P

Leigh
29-Feb-2012, 13:37
Use a medium format camera.

What you're trying to do is not appropriate for LF.

- Leigh

atorger
1-Mar-2012, 05:26
Use a medium format camera.

What you're trying to do is not appropriate for LF.



You're probably right. Large format digital is a rather messy format from start to end. Tiny ground glass, lens color cast, sync cables, sliding backs etc. Compared to a DSLR it does not seem appropriate for anything :-). But if you're like me pressed by economy and only can afford one system it may be interesting to push that system to its limits to expand what you can do - ie it does one thing best (carefully composed with movements high resolution single shots) and that is why I want this system, and with some effort it can be pushed to do a bit more. Composite images is one such thing.

Leigh
1-Mar-2012, 05:51
If you've already decided to use the system...

Why did you waste our time by asking the question?

- Leigh

atorger
1-Mar-2012, 08:24
If you've already decided to use the system...

Why did you waste our time by asking the question?

It is not a definite decision. There are many things to consider, I need the whole picture and make a budget and plan. It is a very costly system so I don't want to buy the wrong things. This is one piece of the puzzle. I could consider dropping one focal length and instead get electronic shutters for the remaining, etc. I think it is very valuable to hear from people with hands-on experience, perhaps hear from someone that does the similar things. From what I hear here the standard copal shutters seems to be easy enough to work with that it will be okay although a little bit messy of course, it is always best if you don't need to touch the camera.

Leigh
1-Mar-2012, 13:05
For minimizing camera movement an electronic shutter would be much better than a mechanical.

Changing the shutter speed on a Copal shutter requires rotation of the speed setting dial, which
may require a bit of force depending on how the shutter is adjusted.

It's possible to minimize the force required, fairly simply, but it will never be zero.

- Leigh

Frank Petronio
1-Mar-2012, 13:18
The Prontors require a stronger push on the release because they are cocking the shutter too, I didn't like them for that reason. They also felt more delicate than a good Compur or Copal, plus lost the higher speeds.

B.S.Kumar
1-Mar-2012, 20:04
Frank, perhaps you're thinking of the older Prontors. I've been using the newer Prontor Professional shutters for a very long time, and never had a problem. I sold a few of them about a year ago, replacing them with non-working shutters for use with my scanning back. While they do need a bit more force to operate, they are certainly not delicate. The later Prontors lose only the top speed of 1/500s or 1/400s - not a particularly great loss for large or medium format usage on a view camera.

I use multiple exposures with film and a digital back, and have had mis-alignment very rarely. A bit of practice will ensure very few mistakes.

Kumar

Tracy Storer
5-Mar-2012, 12:33
Use a press shutter and use 1 and 2 stop ND filters (hand held in front of the lens) if you want to minimize touching the camera.....

rdenney
6-Mar-2012, 05:38
The OP has probably already made his choice, but I hadn't seen the thread before and Tracy brought it back up within view.

I have not heard the OP articulate a reason why he needs a camera with movements, other than to allow practicing on film before purchasing a digital back.

I have a cheaper alternative, if the OP has no interest in movements:

1. Purchase a Pentax 645NII for a few hundred bucks, plus all the lenses needed.

2. Purchase a Pentax 645D new for less than the price of many used digital backs. The sensor size is only slightly smaller than his target (33x44 instead of 36x48). The camera will provide all the electronic controls he requires for his proposed activities.

I don't think I move the camera by cocking or adjusting the shutter, and I don't think it's a substantial risk with a quality camera like the Linhof. But I also think that the Linhof is a view camera, and even though it is beautifully made, it is a view camera and has a different purpose in life. It will be much more difficult to use with much lower integration for the work the OP describes.

Rick "who measures need in terms of proposed applications" Denney

Ole Tjugen
6-Mar-2012, 07:07
I have done many multiple exposures with LF, since many of the scenes around here include running water. Only once have I had any movement while changing the shutter speed in the middle of a 20-exposure exposure, and that was with an old and stiffish Compur shutter.

Ben Syverson
10-Mar-2012, 12:29
Forgive my ignorance about digital backs, but isn't there a way to use the sensor's electronic shutter to take a shot? Or do you need to also have a mechanical shutter?

B.S.Kumar
10-Mar-2012, 19:58
Ben, the sensor doesn't have a shutter. It gets a signal either through the sync-port if a mechanical shutter is used, or through the contacts around the sensor if the camera's electronic shutter is used.

Kumar

CP Goerz
11-Mar-2012, 07:51
Tape the lens board on the camera in addition to using the standard clips, use a second tripod under the front standard.

Wally
12-Mar-2012, 12:13
Tape the lens board on the camera in addition to using the standard clips, use a second tripod under the front standard.

Eh? Is this a reply to some _other_ thread??

E. von Hoegh
12-Mar-2012, 12:43
Eh? Is this a reply to some _other_ thread??

Probably

http://www.largeformatphotography.info/forum/showthread.php?88212-300mm-aero-ektar-MY-GOD!