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Ron Lee
23-Jul-2009, 18:15
A new slip on focal plane gravity fed shutter is now ready for anyone who may be interested in one. Photos of the shutter and photos taken with the shutter on a LF camera can be seen at this link;

http://picasaweb.google.com/Kymtman/AddPhotos?authkey=Gv1sRgCOim-srI1r_IQA#

If you are interested contact me at rtincher@prtcnet.org or rtincher@hotmail.com
These shutters really work from speeds 1/1000 down to 1/8. I have been using a couple of them for the last six months.
Let me know what you may think about this lightweight (4.4oz) unit.
Thanks in advance:

EdWorkman
23-Jul-2009, 18:19
Cool
But that's not at the focal plane- the film is the focal plane
That nitpick aside, Cool

Turner Reich
23-Jul-2009, 22:16
Figure out a way to display the actual travel of the shutter and you will have the golden egg of devices.

CatSplat
23-Jul-2009, 23:16
That looks pretty neat, how does one select shutter speeds?

IanG
24-Jul-2009, 00:54
Two good shutters went unsold on Ebay last night, the seller mis-labelled them as pre-Packard type shutter, while they were Thornton Pickard (or copies).

They often sell for very little and are extremely easy to service/renovate.

Ian

Ron Lee
24-Jul-2009, 03:09
Selecting the speeds is simply removing a pin and repositioning the curtains. Not shown in the photos.

Ron Lee
24-Jul-2009, 03:24
The Thorton-Pickard that is for sale now is much more expensive and looks to out weight the Gatts/Tincher shutter many time over. I don't have to defend the Gatts/Tincher shutter, it has proven itself time and time again! Reich, do you mean the actual travel speed of the shutter? It falls at 32 feet per second, according to Newton.

numnutz
24-Jul-2009, 03:29
But the really big question is - "How Much"

nn :)

Arthur Nichols
24-Jul-2009, 04:52
does it work if it is not vertical?

Morten
24-Jul-2009, 05:18
But the really big question is - "How Much"

nn :)

150$ !! :cool: on http://cgi.ebay.com/Front-mount-focal-plane-shutter-brass-barrel-lens_W0QQitemZ220455798580QQcmdZViewItemQQptZFilm_Cameras?hash=item3354308734&_trksid=p3286.c0.m14&_trkparms=65%3A12|66%3A2|39%3A1|72%3A1234|293%3A1|294%3A50

A bit on the high side for my taste, but you might think otherwise......:rolleyes:

GPS
24-Jul-2009, 06:01
A new slip on focal plane gravity fed shutter is now ready for anyone who may be interested in one. Photos of the shutter and photos taken with the shutter on a LF camera can be seen at this link;

http://picasaweb.google.com/Kymtman/AddPhotos?authkey=Gv1sRgCOim-srI1r_IQA#

If you are interested contact me at rtincher@prtcnet.org or rtincher@hotmail.com
These shutters really work from speeds 1/1000 down to 1/8. I have been using a couple of them for the last six months.
Let me know what you may think about this lightweight (4.4oz) unit.
Thanks in advance:

Ron,
unless you have moderator's permission, business self promoting threads are not allowed on this forum.


The Thorton-Pickard that is for sale now is much more expensive and looks to out weight the Gatts/Tincher shutter many time over. I don't have to defend the Gatts/Tincher shutter, it has proven itself time and time again! Reich, do you mean the actual travel speed of the shutter? It falls at 32 feet per second, according to Newton.

As already mentioned, your shutter is not a focal plane shutter. The fact that you sell them as such on Ebay violate also the Ebay policy. You're misleading people with that description.
Also, Newton speaks about free fall. Your shutter is not falling with free fall. If you measured its speed electronically you would find out that you cannot guarantee its precise speed - it has none.

Ron Lee
24-Jul-2009, 06:53
Yes, it works up to and slightly beyond a 45 degree tilt.
No, it isn't too expensive. Consider the cost of having a lens set in a shutter and the cost of that shutter and furthermore how long will it stay accurate and in my opinion this one is a bargain knowing that you can use it on a variety of lenses. In the photos that you looked at the lens was a 12" Kodak commercial Ektar in a Ilex #4 shutter.

Ron Lee
24-Jul-2009, 07:07
The replies to my original announcement of the shutter led into debates about the shutter. I was led to believe that a new product that was beneficial to the members of this forum could be announced. If not here then where? All references to my email were intended for more information about the item. I will gladly bow out if I have crossed any guidelines. Please accept my apologies.

Kirk Gittings
24-Jul-2009, 08:03
R0n, this bengs in New Products and requires moderator approval first. Srry, My keybard is missing a few letters this morning.
New Products:A forum for announcements of a commercial nature related to large format photography. Moderator approval is required before posting promotional items.
I wi mve it.

benrains
24-Jul-2009, 12:55
Looks like a nice product to me. Some people are maybe being a little over enthusiastic about their nit-picking (i.e. it's not a focal plane shutter). Focal plane shutters are located at the back of the camera where it'd be immediately in front of the focal plane--hence "focal plane shutter". What you've created is a variant of what I've heard referred to as a "drop shutter". I think they used to be fairly common on cameras made back in the late 1800s.

The nit-pick I would add is that you said the travel speed is 32 ft/s taken from Newton's gravity calculations. Which isn't true! 32 ft/s is a velocity, whereas gravity accelerates, and Newton's gravitational value is 32 ft/s^2 (32 ft per second per second.) The only time at which an object in free fall in earth's gravity is traveling at 32 ft/s is 1 sec into the fall. You can still do the shutter speed calculations based on that acceleration, it's just a little more work... or a maybe a lot more work if you try to take friction into account (probably you can ignore the friction unless the lens is tilted forward or backward.)

Still, as long as the calculations are sorted out properly, it would be a very useful device for timing those exposures that are less than 1 second long. I'm not sure what the limit would be, but I'd guess that times at least as fast as 1/30th or 1/60th of sec would be possible.

Ron Lee
24-Jul-2009, 13:56
It really doesn't make that much difference about how fast it drops as long as it is repetitively constant each time, in which it is. The materials chosen work together with almost no resistance. The unit has been calibrated with a shutter tester to speeds from 1/1000 to 1/15th and are always there. I found that you can tilt the shutter forward or to the side to slightly slow the travel enough for about 2/3 stop. The photo of the house in the link was shot early morning and the neg is perfect if there is such a thing.

Ken Lee
24-Jul-2009, 14:15
Genius !!

Since some barrel lenses can get rather large, how wide can it accommodate ?

Too bad this posting was sent as a poll. I normally ignore them, as I presume do others.

You might get more interest if you post as a regular message.

GPS
24-Jul-2009, 14:48
It really doesn't make that much difference about how fast it drops as long as it is repetitively constant each time, in which it is. The materials chosen work together with almost no resistance. The unit has been calibrated with a shutter tester to speeds from 1/1000 to 1/15th and are always there. I found that you can tilt the shutter forward or to the side to slightly slow the travel enough for about 2/3 stop. The photo of the house in the link was shot early morning and the neg is perfect if there is such a thing.
-----------------
From Ebay description - "We want to produce a product that will outlast all others and be more accurate than any shutter made. Weighs only 4.5 oz.
...

This shutter is calibrated at speeds from 1/15th of a second to 1/1000th of a second. This shutter can be tilted forward or to the side for added speeds under 1/15th of a second."
------------------
Ron, apart from the fact that you don't get the Newton law (I didn't want to go deeper into it), you mislead yourself and others with your technical ignorance. Stating that this shutter is "repetitively constant each time", that it "will be more accurate than any shutter made" is the uttermost technical nonsense. As is your statement of "almost no resistance"...etc.
You yourself realize that a mere inclination of the shutter changes already the shutter times... That is the case for all of its time settings, of course. Now, the shutter is not only sensitive to this mechanical inclination but also to the wind blowing around the camera (against it especially) as that changes the slide's resistance against the fall also, etc. Even if you had ball bearings there to limit the friction to repeatable values, even then the precision wouldn't be there.
You'd be much better off if you deleted the technical nonsense from the description and presented it as what it is - a crude timing device that in some circumstances can do...:) I wouldn't be surprise if somebody who takes your claims as true were very angry when discovering the reality - after all, if the reality cannot stand behind your claims you prepare yourself some surprise for a device of 150 $ tooted this way. And very justly so...

Ron Lee
24-Jul-2009, 16:17
I realize that everyone can't be pleased all the time especially if they have been rode hard and put up wet and been left with a raw disposition. Those I ignore, the ones who knows all about everything. You'll find one in every crowd. In my 68 years in life I have run into many of those types. Its better to ignore and prove them wrong with their own theory. With over 500+ shots with the shutter and an accurate Luna Pro, not one shot was incorrect. The proof is in the pudding, and it taste so good. The Newton law I understand but how many of the general public understands. When in Rome speak Italian!

Ron Lee
24-Jul-2009, 19:07
Ken Lee
The larger the lens the larger the shutter. I have a shutter on an Industar 37 300mm with a barrel size of 3.5". The shutter measures 5x12.5" The shutter in the photos measures 4x10.5". A fellow is having one built that has a lens that measures barrel size of 4.25". I suppose one could be made to fit almost any lens.

Jim Michael
24-Jul-2009, 19:43
The speed the shutter curtain travels is going to vary with the angle of tilt somewhere on the order of R * cos theta for a tilt of theta from the vertical for your typical rate of travel R. If you replace gravity with a constant force k (say from a rubber band) then the tilt would be less of a factor, perhaps make the travel horizontal. Interesting product.

RichSBV
24-Jul-2009, 21:51
Since Ron has made the claims of accuracy, I would like a question answered...

A couple years ago I looked into making a behind-the-lens guillotine type shutter. The basic design is overly simple. Then using a modified Speed Graphic shutter with actual calibrated speeds. It all sounded simple until one single thought screwed the whole idea up...

The accuracy of the shutter speed can only be calculated for one single lens focal length, one single focal distance and one single film size. Change any of those and the real shutter speed at the film plane changes. That's why guillotine shutters died out while the Speed focal plane shutters lived on...

If you want to think simply, try holding a 3 foot stick from the tip and wave it back and forth. The tip you're holding is considered the back of the lens. Place your imaginary film at any point along the stick. The stick waves back & forth at a constant speed (as does the shutter). The stick itself represents the thin line of light that passes through the slit in the shutter as it travels. As you move from the 'film' towards the rear end of the stick, the effective speed of the stick passing by the 'film' increases. This would be the same as changing the focal length of the lens or the focus distance. A guillotine shutter can not possibly give the same exposure at the film plane for a varying distance of lens to film. As far as gravity goes, that's a 'gimmee' and why I looked into a controlled shutter curtain with a constant speed.

If you've found a way around this, I'd sure like to hear about it...

GPS
24-Jul-2009, 22:27
I realize that everyone can't be pleased all the time especially if they have been rode hard and put up wet and been left with a raw disposition. Those I ignore, the ones who knows all about everything. You'll find one in every crowd. In my 68 years in life I have run into many of those types. Its better to ignore and prove them wrong with their own theory. With over 500+ shots with the shutter and an accurate Luna Pro, not one shot was incorrect. The proof is in the pudding, and it taste so good. The Newton law I understand but how many of the general public understands. When in Rome speak Italian!

Ron,
still speaking nonsense? It is clear that your technical expertise in this field is of the same order as your knowledge about the focal plane. Your honesty is in question, so serious it is. Hopefully the people you mislead with your claims will understand it from the Ebay description of your "precise" shutter. If not they will be defrauded of their money, to put it plainly... You'd better to tell them honestly that with your "precise" shutter they cannot make tilts with the front standard, use lenses of a different diameter without loosing the shutter speed - to add to the list of other sources of imprecision... :rolleyes:

Ron Lee
25-Jul-2009, 00:15
If I sent you a shutter to test, would you return it afterward?

GPS
25-Jul-2009, 00:37
I would but I'm in Europe for the moment and to send it back would cost me more than I would like to pay for the proof. But no amount of testing can remove the basic physical limitation of the construction (inclination sensitive beside all the other imprecision sources also those mentioned by RichSBV).

eddie
25-Jul-2009, 04:35
I would but I'm in Europe for the moment and to send it back would cost me more than I would like to pay for the proof. But no amount of testing can remove the basic physical limitation of the construction (inclination sensitive beside all the other imprecision sources also those mentioned by RichSBV).

wow! you bash on the guy in public, (a simple kind PM would have sufficed i would have imagined) and then you will not even try it because of a few pennies of shipping cost! damn!

Ron Lee
25-Jul-2009, 06:46
The Thornton Pickard shutter( http://licm.org.uk/livingImage/Shutters-Blind.html ) wasn't even close to the film plane (as much as 12" in some case) but slightly behind the lens and used a curtain with a constant slit cut in it, similar to mine, and governed the speed of the scan by the tension of the return spring when cocked. The Packard wasn't close either. Regulating the speed of travel with a given opening in the curtain can render same exposure as by regulating the opening with a constant speed. Take any lens and modern shutter, you have a choice of combination to get the same exposure. Whether the light regulator is in front of or in rear of the lens makes little difference, it still regulates the amount of light striking the film. I will admit that there is a small deviation in travel speed curtailed by drag resistance and an unmeasurable amount of resistance caused by a light breeze, unless you are shooting in winds that would topple your camera. What matters is the end result, that you get the exposure that you want without having to use calculus to figure the variables that will not have any effect on a film that has a greater deviation within itself. Take a box of film, load a couple of holders, return the box to the cooler and in a couple of weeks you find that the speed of the film has changed in the film holders. I think that you will agree with me that in photography there is no need to split hairs. If you find that you over exposed use the zone system to compensate. My last word is my shutter works by the method of practical application.

Arthur Nichols
25-Jul-2009, 07:05
I have been using quite successfully for about 4 years now a speed graphic focal plane shutter on the front of my Deardorff, behind my lenses. The concept of the stick is valid with the exception being that what is moving at the end of the stick is a point and what is moving at the film plane with a slot shutter is a slot and the size of the slot varies with the focal length, being larger the longer the focal length. I believe the change in the slot size at the film plane compensates for the change in the speed of travel.
My experience with many sheets of film has shown that concept of a slot shutter at the front of the camera is a valid concept.
I think is a interesting product and am happy to see that there are some others who realize that there is a gap in the current market for a reasonablly priced univeral shutter.
I agree that some of controlling mechanism like a spring or rubber band might be an improvement and add some consistency, but I have not used the shutter so I can speak from experience.
The proof would be in the pudding so to speak. Test the gravity shutter against a calibrated shutter and check it out. It would be simple to perform. I would volunteer to do this but I cannot add another task to my current list, but maybe another fellow forum member would be willing to do this test and post the results.

Ron Lee
25-Jul-2009, 08:01
It is good to see that there are some who have a bit of common sense. I would like for someone to prove to me what the difference of light control in front and in rear of the lens would be. I have a 12" lens with a leaf shutter that I have shot two plates, one with the leaf shutter and one with my shutter attached and for the love of Gd I could not find one ounce of difference. The shutter is between the lens group in the leaf shutter and I don't have a packard to compare shots in front and in back of.

Ron Lee
25-Jul-2009, 10:38
The front mount shutter was introduced in the late 1800's as evident of the Thornton Pickard front mount model as seen here; http://cgi.ebay.com/g60-ANTIQUE-wooden-camera-shutter-THORNTON-PICKARD_W0QQitemZ230345415905QQcategoryZ15248QQcmdZViewItemQQ_trksidZp3907.
m263QQ_trkparmsZalgo%3DSIC%26its%3DI%252BC%26itu%3DUCI%252BIA%252BUA%
252BFICS%252BUFI%26otn%3D14%26po%3DLVI%26ps%3D54
and someone said it wouldn't work. This one looks to weigh quite heavy. Could be the reason for the decline. If I had the money I would pick it up just for the antique value.

Ron Lee
25-Jul-2009, 13:10
I would but I'm in Europe for the moment and to send it back would cost me more than I would like to pay for the proof. But no amount of testing can remove the basic physical limitation of the construction (inclination sensitive beside all the other imprecision sources also those mentioned by RichSBV).
GPS,
I'm not sure that you know of what you speak when you say "the basic physical limitation of the construction" when you haven't seen the unit and you know nothing of the tolerances in the constructions. I will load the holder with two sheets and shoot completely vertical, the other I will tilt to the max (aprox. 45 degrees) and scan both film together with no corrections whatsoever, then would this convince you? Frankly I am not trying to convince you, but others whose confidence that you have destroyed in the unit with your split hair jargon non- sense. I just don't know why I bother! I heard the cry several times for a shutter that could be mounted on the lens that works, not for the profit but for the humanity of man was it built. You should know that we are all united is some way one to another for no man is an island. Look me in the eye and tell me that I know not of what I speak.

IanG
25-Jul-2009, 13:25
You can get Thornton Pickard shutters for bout $16 / £10, they are extremely easy to restore, even if you have to make a new blind :D

And they'll most likely be more reliable. They aren't heavy, they are small and compact.

Ian

Jim Michael
25-Jul-2009, 13:33
It doesn't really matter whether the speed changes with tilt, as long as the change is consistent and can be documented as part of a calibration process. I think a more useful analysis might be performed by taking some electronic measurements of the shutter speed variation with tilt. There's a pretty easy to build shutter tester you can make with a few easily obtainable components, one example at http://www.hrtranslations.com/photo/shutter_v2/shutter2.html

Turner Reich
25-Jul-2009, 14:56
It doesn't really matter whether the speed changes with tilt, as long as the change is consistent and can be documented as part of a calibration process. I think a more useful analysis might be performed by taking some electronic measurements of the shutter speed variation with tilt. There's a pretty easy to build shutter tester you can make with a few easily obtainable components, one example at http://www.hrtranslations.com/photo/.../shutter2.html

That's what I'm saying but build one into the shutter with a on-board readout.

RichSBV
25-Jul-2009, 21:44
I have been using quite successfully for about 4 years now a speed graphic focal plane shutter on the front of my Deardorff, behind my lenses. The concept of the stick is valid with the exception being that what is moving at the end of the stick is a point and what is moving at the film plane with a slot shutter is a slot and the size of the slot varies with the focal length, being larger the longer the focal length. I believe the change in the slot size at the film plane compensates for the change in the speed of travel...


Arthur,

Thanks for that thought. I wish I would have had it years ago when I looked into making such a shutter. I'll have to put some more thinking into this to see if I may still invest the time into it now.

As for accuracy claims though, it still presents a problem of the original slit distance from the lens, front or rear. It can still only be accurate for any lens at a specified distance from the lens (most probably the nodal point). If, for example, you front mount and then screw on a filter, you move the slit further away from the lens. This would change the effective speed at the film plane. Maybe we need a math person to clear it all up? :p

I think it's great that this shutter exists and there is interest in it, but some reality checks may be in order...

Ron Lee
26-Jul-2009, 03:48
Arthur,

Thanks for that thought. I wish I would have had it years ago when I looked into making such a shutter. I'll have to put some more thinking into this to see if I may still invest the time into it now.

As for accuracy claims though, it still presents a problem of the original slit distance from the lens, front or rear. It can still only be accurate for any lens at a specified distance from the lens (most probably the nodal point). If, for example, you front mount and then screw on a filter, you move the slit further away from the lens. This would change the effective speed at the film plane. Maybe we need a math person to clear it all up? :p

I think it's great that this shutter exists and there is interest in it, but some reality checks may be in order...

The actual shutter distance from the lens of my unit is sitting at 2mm . Not unlike Jim Galli's shutter, my theory is almost identical to his and what about using your lens cap, do they work? I don't know much about what goes on between the lens and film other than the stick demo and I can deal with that. Do a simple test; cut a thin slot in a dark piece of stiff paper and slowly pass it across the front of your lens when you are focused on a scene and you can actually watch what is happening to your film. The light is dim at first then gets brighter then fades with the subject being displayed at all times. Hope this helps.

Ron Lee
26-Jul-2009, 13:38
Hope i'm not talking to myself! Back with the shutter test with the electronic testor and here are the results. I had little time to go through all the speeds. Vertical= 1/20th, 26degree tilt=1/17th, and last 45degree tilt=1/10. I might add that at the vertical position the shutter drops without touching the envelope that I could tell. Here are the actual numbers respectively, 0.049987, 0.05953, 0.09878. these are elapsed times.

Gordon Moat
26-Jul-2009, 15:16
I have seen many images of Guillotine shutters in old photography publications. They were somewhat proven around a century ago. The only accuracy I would wonder about today would be their usability with transparency films, since those are more exposure critical.

I did look into making a Guillotine shutter, though I ended up finding a large diameter Wollensak shutter that solved my exposure needs. While that only has four shutter speeds, and no flash sync, it works reliably and packs small into my main 4x5 bag.

I think the shutter you have is a great idea, and I wish you luck with selling a few. I have no doubt that some people will find these quite useful. Don't get too bent out of shape with the negative comments, since I doubt any of those guys even use brass lenses without shutters.

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

Arthur Nichols
27-Jul-2009, 11:29
As far as the question of varying exposure depending on the focal length: I honstly do not have the math skills to work this out. I would suspect that setting aside all other considerations like tilt angle and so on, that a slot of a given size would always give the same exposure regardless of the distance from the shutter to the film plane. With my admittedly limited understanding: I think that the speed of the slot as it moves across the film plane does vary with the distance from the shutter to the film plane but is always compensated for by the fact that the further away from the film plane the shutter is the larger the area of film that gets wiped.
To recap: the longer the distance from film plane, the faster the traverse of the slot across film but by a larger area.

Mark Sawyer
27-Jul-2009, 15:20
A couple years ago I looked into making a behind-the-lens guillotine type shutter. The basic design is overly simple. Then using a modified Speed Graphic shutter with actual calibrated speeds. It all sounded simple until one single thought screwed the whole idea up...

The accuracy of the shutter speed can only be calculated for one single lens focal length, one single focal distance and one single film size. Change any of those and the real shutter speed at the film plane changes. That's why guillotine shutters died out while the Speed focal plane shutters lived on...



As far as the question of varying exposure depending on the focal length: I honstly do not have the math skills to work this out. I would suspect that setting aside all other considerations like tilt angle and so on, that a slot of a given size would always give the same exposure regardless of the distance from the shutter to the film plane...

The format and focal length wouldn't matter. If a shutter is open for a tenth of a second, the shutter is open for a tenth of a second. That was bad information slipping in, which sometimes happens...

Ken Lee
27-Jul-2009, 17:21
Ken Lee
The larger the lens the larger the shutter. I have a shutter on an Industar 37 300mm with a barrel size of 3.5". The shutter measures 5x12.5" The shutter in the photos measures 4x10.5". A fellow is having one built that has a lens that measures barrel size of 4.25". I suppose one could be made to fit almost any lens.

Brilliant !!

I have a Sinar with a Sinar Shutter, and but tops out at 1/60. I've often wanted to take photos outdoors at higher speeds.

Could the same shutter be adapted to fit on a variety of lenses ?

Ron Lee
27-Jul-2009, 19:08
Brilliant !!

I have a Sinar with a Sinar Shutter, and but tops out at 1/60. I've often wanted to take photos outdoors at higher speeds.

Could the same shutter be adapted to fit on a variety of lenses ?

It sure can. Lets say your largest lens glass size was 3" and your smallest lens glass size was 1.5", then I would cut the envelope to slightly over the glass size and then build the sleeve to your barrel size, say 3.25". then using a firm foam rubber cut to fit your smaller barrel size. Because the shutter is so light a moderate foam rubber will support the weight. I am in the process of building a lens shade to snap on the shutter, a filter holder that can be adjusted for the proper filter and larger ones. Also a flash sync is in the process, it is a relatively simple fix. Be patient and we will have a very productive shutter very soon. Ken, I would like to send you one to test if you would post your findings on this forum and return it later to me. Let me know your lens size and your barrel size and I will put one together for you.

GPS
29-Jul-2009, 11:35
...
I think that you will agree with me that in photography there is no need to split hairs. If you find that you over exposed use the zone system to compensate. My last word is my shutter works by the method of practical application.

In photography, when you use exposure speeds of 1/1000 s you are splitting hairs, and very much so. By saying it's not so you just add to your technical ignorance expressions.
Let's not avoid the main issue here - Ron is selling a product about which he boasts that it is "more accurate than any shutter made". Nobody with common sense can deny that this statement is fraudulent. What we have here is more than an amateur with his technical ignorance.
I hope that somebody on Ebay will give him a lesson that a product for 150 $ needs to deliver what is boasted about it. That is obviously not the case here.

GPS
29-Jul-2009, 11:42
wow! you bash on the guy in public, (a simple kind PM would have sufficed i would have imagined) and then you will not even try it because of a few pennies of shipping cost! damn!

In the country I'm for the moment being, to send a parcel, even a small one, to the US would cost several tens of dollars. Your "few pennies of shipping cost" is therefore nonsense. Damn yourself... And again, try to see the people, who will pay 150 $ for this shutter, tooted as more accurate than any shutter, just to discover the truth behind this 150 $ "accurate shutter"...

GPS
29-Jul-2009, 11:47
It doesn't really matter whether the speed changes with tilt, as long as the change is consistent and can be documented as part of a calibration process. I think a more useful analysis might be performed by taking some electronic measurements of the shutter speed variation with tilt. There's a pretty easy to build shutter tester you can make with a few easily obtainable components, one example at http://www.hrtranslations.com/photo/shutter_v2/shutter2.html

It really doesn't matter? If you need to measure precisely the amount of tilt on your front standard, then to calculate the effective change of the exposure, then to make exposure corrections and all this with a shutter sensitive even to the wind direction and its strength - it doesn't really matter? Good for you...:)

gevalia
29-Jul-2009, 17:17
It really doesn't matter? If you need to measure precisely the amount of tilt on your front standard, then to calculate the effective change of the exposure, then to make exposure corrections and all this with a shutter sensitive even to the wind direction and its strength - it doesn't really matter? Good for you...:)

You know, I'm sure everything you're saying or ever said is right. But man, what is your problem? Seriously.

Ron Lee
29-Jul-2009, 17:58
GPS; there you go again making false and misleading statements saying that we make the most accurate shutter made; this is what is stated in the description of which you refer; "We want to produce a product that will outlast all others and be more accurate than any shutter made. Weighs only 4.5 oz.", you are misleading readers and stand to be corrected in almost everything you state. I personally would bar you from this forum and any others that I had control of if it were me. There is another thread related to bashing, try it.

GPS
30-Jul-2009, 00:50
Ron, the product you want to make - a shutter "more accurate than any shutter made" - is the shutter you sell on Ebay?
When it comes to misleading statements, why do you mislead people with your technically false statement (in the Ebay title!) that your shutter is a "focal plane shutter"? Let alone your other misleading statements in your Ebay listing in the description of your shutter...

GPS
30-Jul-2009, 01:10
Just so that people could see what is the technical description of the shutter on Ebay:
----
"Up for sale is a focal plane shutter, newly built of the finest most durable materials available. These shutters are hand crafted with attention to the smallest details. It takes several hours to assemble, calibrate and test each one of these units. We want to produce a product that will outlast all others and be more accurate than any shutter made. Weighs only 4.5 oz.

This shutter is a gravity powered shutter not needing any springs or other devices that weaken or fail over time. This shutter is non-invasive to your camera. It is designed to slip onto your lens and can be adjusted with foam to fit any lens barrel from 3” down to 1.5” lens. If you have a lens in a shutter that is not accurate, then set it to “T” and slip on this shutter for one that is as accurate as Newtons law of gravity.

This shutter is calibrated at speeds from 1/15th of a second to 1/1000th of a second. This shutter can be tilted forward or to the side for added speeds under 1/15th of a second. It comes with complete instructions from the designer and architect. Some of those that have bought this shutter, who knows the crew, have nicknamed the shutter the “Gatts Guillotine” because it slices off a piece of light, they say.

We offer these units at a 'Buy it Now' introductory price of $150.00 . These units are limited to production because we can only build and test a few each week. I am linking you to a page with photos of the unit on camera and photos taken with the shutter. I am sure that you will be more than delighted to shoot with this unit. http://picasaweb.google.com/Kymtman/AddPhotos?authkey=Gv1sRgCOim-srI1r_IQA#

The cable release is for reference only. It is not included.
We have been designing and testing these units for the past six months, and now they are ready for your camera. Shipping USPS $5.95 Not ready to ship overseas. US and canada only.
If you have questions please don't hesitate to email me. I'll do my best to give you a truthful answer as possible. I have several lenses in Ilex shutters etc., but I find myself using my own built shutter for the simple reason that I can trust the results.
The cable release is for reference only. It is not included.
We have been designing and testing these units for the past six months, and now they are ready for your camera. Shipping USPS $5.95 Not ready to ship overseas. US and canada only.

If you have questions please don't hesitate to email me. I'll do my best to give you a truthful answer as possible. I have several lenses in Ilex shutters etc., but I find myself using my own built shutter for the simple reason that I can trust the results."
-------------

The shutter is still listed as a "focal plane shutter" even if it is not in any case such a shutter...

Ron Lee
30-Jul-2009, 09:16
Ron, the product you want to make - a shutter "more accurate than any shutter made" - is the shutter you sell on Ebay?
When it comes to misleading statements, why do you mislead people with your technically false statement (in the Ebay title!) that your shutter is a "focal plane shutter"? Let alone your other misleading statements in your Ebay listing in the description of your shutter...

I've seen only two types of shutters, the focal plane and the leaf, this isn't for sure a leaf shutter is it. Now what is misleading about " We want". Now prove to me it isn't more accurate over time than any spring powered shutter. Gee when are you going to let up. It seems that I can't rectify the title description or at least at this time in the listing. I will list the next one without the word "focal plane" if that suites you. Now on to newer and better things. Lets discuss how to calculate the speeds between the lens and focal plane of the film. I spent a few minutes this morning to answer some ones question about how the speed changes when a shutter is placed between the lens and film.

Shutter speeds:

Someone wanted to know how to calculate the shutter speed of a shutter placed behind the lens. Let us look at the conical projection behind the lens and move the shutter to different places along the center line and calculate the image circle at each place. Now let us use some hypothetical values in the equation . Rear diameter of lens =40mm , focal length =250mm, Image circle =215mm ( just enough to cover a 5x7) well almost. Now lets place the shutter at the very back of the lens with a 1mm slit and say the shutter is moving across the projected image at 10mm per second (quite slow wouldn’t you say). At that position it would take 4 seconds to move across the lens and exposing the film. Now move the shutter to a new location say 25mm along the center line. Calculate the IC (image circle) at that point. We find if we divide the projected image circle at the film plane (215) by 2 and subtract one half of the diameter of the lens we have 87.53mm, now divide this by the focal length (250) we get 0.35012, the tangent of the angle of projection above the straight line of the lens. Using 20mm (1/2 of the lens diameter) into account we can figure the foci of the lens. I’ll not get into that. Now multiply 25mm by 0.34012 we get approximately 8.75mm, now double this and add the 40mm for the lens and you get a total of 57.5mm IC diameter, taking the shutter 5.75 seconds to cross at the rate given. Using same formula of simple trig we get @50mm IC=75.01(7.5 sec.), @125mm IC=127.53 (12.75 sec. ) and @ 250mm (at the film) IC=215.06 taking 21.5 seconds to cross the film plane. You can think of this as a cone of ice cream being sliced at these points. Definitely the closer to the film plane the longer it takes thereby giving a slower exposure speed. These are my calculations and one mode of thinking to solve the speed problem. I will state that I stand to be corrected.

GPS
30-Jul-2009, 09:55
I've seen only two types of shutters, the focal plane and the leaf, this isn't for sure a leaf shutter is it. Now what is misleading about " We want". Now prove to me it isn't more accurate over time than any spring powered shutter.
...

Your guillotine shutter pases in front of a small diameter (28 mm) Ektar 203mm lens. Then you put it in front of a Nikon 90mm/4,5 lens with a diameter of 70 mm (2,5 longer diameter). The shutter falls on a 2,5 longer length to close. You would need to have 2,5x higher speed of the falling shutter to keep the same exposure time. You don't have that. Figure out yourself what it means in terms of exposure accuracy.

As for the rest - Littman seems to be a serious scientist in comparison with you...:)

Ron Lee
30-Jul-2009, 15:58
GPS;
'Matthew Brady used a shutter in 1850. This, like the Fizeau and Foucault unit was a "drop" or "guillotine" shutter,' Maybe Brady had only one lens and others in that era using the guillotine shutter. I have a wide variety of lenses from f/4.5 300mm front glass measuring 66mm to f/7 250 glass measuring 35mm, and on one occasion I ran a comparison test of six lenses in the same hour and used the same combination of exposures and for the love of me I could not tell an ounce of difference of exposure to the film. That is why that I have always stated the shutter has never failed me. You can take this subject as far as you want, but for me I think that history speak the loudest and my test has satisfied me and should be quite helpful to those who don't want to invest a small fortune is having their glass set in an expensive shutter. If the shutter isn't what is stated I will and have always said that we will gladly refund their money. Read again the listing. What more do you want man, blood!.....I heard that!

GPS
30-Jul-2009, 16:10
GPS;
'Matthew Brady used a shutter in 1850. This, like the Fizeau and Foucault unit was a "drop" or "guillotine" shutter,' Maybe Brady had only one lens and others in that era using the guillotine shutter. I have a wide variety of lenses from f/4.5 300mm front glass measuring 66mm to f/7 250 glass measuring 35mm, and on one occasion I ran a comparison test of six lenses in the same hour and used the same combination of exposures and for the love of me I could not tell an ounce of difference of exposure to the film. That is why that I have always stated the shutter has never failed me. You can take this subject as far as you want, but for me I think that history speak the loudest and my test has satisfied me and should be quite helpful to those who don't want to invest a small fortune is having their glass set in an expensive shutter. If the shutter isn't what is stated I will and have always said that we will gladly refund their money. Read again the listing. What more do you want man, blood!.....I heard that!

Ron, read again your listing - there is nothing about that you will "gladly refund their money". You start to invent more than just shutters...:rolleyes:

Ron Lee
30-Jul-2009, 19:29
GPS;
Look at the "Return Policy" under the "Shipping and Payments" tab. Stated quite clearly. " 7 days after the buyer receives it Money back.
It would be nice if you get your facts straight before making a bold statement. Could be cause for a liable suit for you some day if you aren't careful. But we here, of course, do not know that you are a person, just 3 letters of the alphabet.

GPS
31-Jul-2009, 02:05
...
If the shutter isn't what is stated I will and have always said that we will gladly refund their money. Read again the listing. What more do you want man, blood!.....I heard that!


GPS;
Look at the "Return Policy" under the "Shipping and Payments" tab. Stated quite clearly. " 7 days after the buyer receives it Money back.
It would be nice if you get your facts straight before making a bold statement. Could be cause for a liable suit for you some day if you aren't careful. But we here, of course, do not know that you are a person, just 3 letters of the alphabet.

Ron,
read again your listing - nowhere, not even under the "Shipping and Payments" tab do you state that "we will gladly refund their money". Nowhere! You have never said that in your listing. It would be nice if you get your facts straight before making a bold statement...:)
Indeed, you invent more than just shutters...:rolleyes:

Ron Lee
31-Jul-2009, 04:14
"Ron,
read again your listing - nowhere, not even under the "Shipping and Payments" tab do you state that "we will gladly refund their money". Nowhere! You have never said that in your listing. It would be nice if you get your facts straight before making a bold statement...
Indeed, you invent more than just shutters...
__________________
GPS "

No where does this statement refer to my listing on the bay. The reference was to the ones who have made inquires about the product. I think it is time to end this childish game you are playing and I know without a doubt that you will have to have the last word so give it your best shot. Have a nice day.

GPS
31-Jul-2009, 05:47
GPS;
...
If the shutter isn't what is stated I will and have always said that we will gladly refund their money. Read again the listing. ..


"
GPS "

No where does this statement refer to my listing on the bay. The reference was to the ones who have made inquires about the product.
...

Ron,
you gladly contradict yourself. :) Too bad for your inventing...

Nathan Potter
31-Jul-2009, 11:07
If we look at the situation of a slit moving down across the lens field of view at a small distance in front of the lens then such a slit will be imaged at the film plane as a blurred slit at least at the edges and if the slit is narrow enough it will be totally blurred depending on the size of the lens aperture. As the slit is moved further away from the lens two things happen. First a given sized slit is imaged smaller at the film plane and that slit will take longer to travel over the film plane assuming constant downward velocity in both cases. I think the light intensity and distribution will not change significantly within the slit as a function of distance from the lens. Of course the slit must in all cases cover the dimensions of the film. I believe, to a first approximation, that the longer slit travel time negates the the effect of the smaller slit size as one moves the assembly further from the front of the lens. IMHO then there may not be much exposure sensitivity to distance of the shutter from lens.

Other issues of quality, tilt and cost effectiveness can be reasonably debated. :) :)

Nate Potter, Washington DC.

Ron Lee
31-Jul-2009, 17:17
If we look at the situation of a slit moving down across the lens field of view at a small distance in front of the lens then such a slit will be imaged at the film plane as a blurred slit at least at the edges and if the slit is narrow enough it will be totally blurred depending on the size of the lens aperture. As the slit is moved further away from the lens two things happen. First a given sized slit is imaged smaller at the film plane and that slit will take longer to travel over the film plane assuming constant downward velocity in both cases. I think the light intensity and distribution will not change significantly within the slit as a function of distance from the lens. Of course the slit must in all cases cover the dimensions of the film. I believe, to a first approximation, that the longer slit travel time negates the the effect of the smaller slit size as one moves the assembly further from the front of the lens. IMHO then there may not be much exposure sensitivity to distance of the shutter from lens.

Other issues of quality, tilt and cost effectiveness can be reasonably debated. :) :)

Nate Potter, Washington DC.

Nathan did you try the experiment that I suggested, taking a dark stiff board and cut a small slit across it and pass it across the front of your lens, Try a 1mm slit (the smallest of my settings) and see for yourself what is happening. You may want to place it stationary somewhere across your lens and view you focus screen with your loop, then you can be assured of what is projected onto your film. A simple test of my shutter's qualifications. The shutter that we build does cover the lens glass and then some to make sure it doesn't retard the projected image.
Gentlemen, I had no intent to sell anything on this forum other than my integrity. Most of my post have been to defend the validity of my product. Some have even dragged ebay into the equation> My intent was merely to inform the readers here that there was an alternative means to an end concerning shutters, just another option. My email reference was to answer additional questions that they might have.
I don't need the money, but think that anyone should be rewarded for his labors. I am a retired land surveyor and my financial status is well cared for. I would like to be know as someone who cared. I know that I may have been rude at times, but sometimes it takes rudeness to get someones attention. I've been called everything except a milk cow on this forum and just waiting for that too. Guys, I have even offered a shutter for testing but was refused, and that leads me to think that some of you may sincerely enjoy ridicule. I was taught as a child to give someone a chance, but times have changed haven't they.

Ron Lee
1-Aug-2009, 04:13
Thanks Van Camper, for the advice. I really appreciate your approach. Straight to the point. No more will be said about the *******.

Gordon Moat
1-Aug-2009, 15:21
It would be quite nice to see this shutter tested for View Camera magazine. Perhaps someone can lead the way to make that possible. Speculation one way or the other without actual data serves no purpose beyond fueling arguments. On a very simple presumption, gravity changes very little with altitude, and can be considered reliable; considering that many shutters are off a bit at each setting, I would rather know accuracy of settings than other claims. The slit width idea has been used many decades in focal plane shutters, so the basic idea of that is not new.

I would prefer to see something like this on the market, than to see no solution. Some here address this in such a manner that it seems they would rather kill off such ideas. Yet when products do disappear, is it any surprise when people bitch about the lack of innovation or attempts to make anything. If this is the place for Large Format, then the voices of discouragement are louder than encouragement. I think that is quite sad and a poor reflection upon this forum.

Criticism can lead to better products, but only if it is constructive. This product does compete with older leaf shutters, and I do think pricing is a consideration. However, compare this shutter to a Packard, and I think we would find different viewpoints. Does anyone here actually want this type of shutter in the market? I do.

don12x20
1-Aug-2009, 16:49
Criticism can lead to better products, but only if it is constructive. This product does compete with older leaf shutters, and I do think pricing is a consideration. However, compare this shutter to a Packard, and I think we would find different viewpoints. Does anyone here actually want this type of shutter in the market? I do.

I agree, Gordon.

I do want this shutter to succeed as well.

I certainly don't need it for any of the modern glass I have.

Yet there are many of us that have many older pictorialist lenses that have no shutters what-so-ever. While we're adept at using cards (in a handheld slit arrangement much less accurate than what Ron offers!), hats, berets, lens caps, and even the Packard Shutter with its maximum of 1/25th second, ...all of us dream of using faster films (even 100 ASA) with these lenses in normal lighting conditions, and that requires a faster shutter (or wait for dark and use 25 ASA Efke film).

So, Ron, continue to develop your shutter. Make it -- but a little larger in diameter-- and they will come.

Don't fall prey to the few whiners that can't comprehend what you are trying to implement, or that you aren't competing at all with modern shutters. There is actually a market for it for anyone that has a Petzval, Pinkham, Cooke, Ross or Verito.

We presume that the images of you made on the website are indeed made with this shutter? If so, then it appears to do something correctly.... (Ron please confirm)

Ron -- so make one with a 5 1/2 inch hole, and we'll mount it on a coated Cooke Series VIa soft focus 460mm Knuckler (weighs 10+ pounds and barely fits on a 171x171 arca swiss board...the weight of this lens alone will destroy the front of most modern view cameras...)....lets see what the shutter can do.

Ron Lee
1-Aug-2009, 17:53
The photos posted in reference to the item being discussed ( said not to mention it again) are not manipulated, but actual results of the item being discussed here on this forum. I was about to loose face in this forum and go else where with my idea. So glad to see there are some that can see the need. I should have been more specific as to the type of lens this item was to target, though I did list brass lens and barrel lens. Are you serious about a 5.5 lens size, or just yanking my chain?
In the second week of Oct I will be at Natural Bridge shooting with my item and a variety of brass lens. I really like the tone these lenses produce. This year should be a great year here in Ky for Fall foliage because of all the rain that we have been getting. Sub soil moisture should carry through until late Oct with no additional rain. I live about an hour away and hope to get a group together for a two day outing.

Don7x17
1-Aug-2009, 17:59
The photos posted in reference to the item being discussed ( said not to mention it again) are not manipulated, but actual results of the item being discussed here on this forum. I was about to loose face in this forum and go else where with my idea. So glad to see there are some that can see the need. I should have been more specific as to the type of lens this item was to target, though I did list brass lens and barrel lens. Are you serious about a 5.5 lens size, or just yanking my chain?
In the second week of Oct I will be at Natural Bridge shooting with my item and a variety of brass lens. I really like the tone these lenses produce. This year should be a great year here in Ky for Fall foliage because of all the rain that we have been getting. Sub soil moisture should carry through until late Oct with no additional rain. I live about an hour away and hope to get a group together for a two day outing.

Quite serious about the Cooke. Jim Galli can confirm. And its coated circa 1956. A real brass beauty.
Several other large Petzvals in the collection have 4.5 inch element.

Ron Lee
1-Aug-2009, 18:39
"Ron -- so make one with a 5 1/2 inch hole, and we'll mount it on a coated Cooke Series VIa soft focus 460mm Knuckler (weighs 10+ pounds and barely fits on a 171x171 arca swiss board...the weight of this lens alone will destroy the front of most modern view cameras...)....lets see what the shutter can do."
Don could you email me a photo of this camera and lens along with its measurements and I will see what I can do. rtincher@hotmail.com

Ron Lee
3-Aug-2009, 16:00
Someone wanted to know about free fall guillotine shutter speeds. Here is the formula;
D=Vi*T+1/2*A*T^2
According to this formula a shutter falling 2.5" from a rest state has a velocity of 2.49mph or 3.652' feet per second. In 1/30 of a second will travel 1.45" inches. Great for a lens of this diameter for a true 1/30 setting.
A shutter falling 5" with travel 2.06" in 1/30 of a second, will cover 41% of a 5" lens. This will delay the time and by adjusting the shutter setting 1 &1/3 stops the correct settings can be acquired. This is what is accomplished if someone wants to build a shutter for different sizes of lens. On lens from 1.5" to say 2.5" (glass size) there would be very small correction needed to get a good printable negative. Hope this is of some benefit to at least a few interested members here.

GSX4
4-Aug-2009, 12:54
Ron, I am curious about this shutter even with all the ballyhoo it's created. I am interested in how you make the adjustments to get the speeds you say can be created?

GPS
4-Aug-2009, 14:17
Someone wanted to know about free fall guillotine shutter speeds. Here is the formula;
D=Vi*T+1/2*A*T^2
According to this formula a shutter falling 2.5" from a rest state has a velocity of 2.49mph or 3.652' feet per second. In 1/30 of a second will travel 1.45" inches. Great for a lens of this diameter for a true 1/30 setting.
A shutter falling 5" with travel 2.06" in 1/30 of a second, will cover 41% of a 5" lens. This will delay the time and by adjusting the shutter setting 1 &1/3 stops the correct settings can be acquired. This is what is accomplished if someone wants to build a shutter for different sizes of lens. On lens from 1.5" to say 2.5" (glass size) there would be very small correction needed to get a good printable negative. Hope this is of some benefit to at least a few interested members here.

A formula for free fall? But your shutter is not a case of free fall... It has friction not constant but changing with front standard tilt, among many other influences. Those who wanted to know about the shutter and know physics must have a clear idea by now about your claims...

Don7x17
4-Aug-2009, 14:32
Ron, I am curious about this shutter even with all the ballyhoo it's created. I am interested in how you make the adjustments to get the speeds you say can be created?

Ron - do you have an adjustable slit in the shutter?

Ron Lee
4-Aug-2009, 15:06
Ron, I am curious about this shutter even with all the ballyhoo it's created. I am interested in how you make the adjustments to get the speeds you say can be created?

Andrew; The adjustments are made by increasing or decreasing the size of the slit. Thanks for asking.

Steven Tribe
19-Sep-2009, 13:41
This is a very old idea and probably covered by scores of 19th C patents. Problems are variable friction (changes in temperature and moisture/dirt/polishing on the friction surfaces) and acceleration (the terminal velocity is reached after a few meters - the top half of the lens get longer exposure than the bottom half). A certain amount of weight in the slide would help reliability. If I make one, I would use a set of strips (very much like a set of Waterhouse stops) with different slot widths rather than fiddling around with adjustments.

Ron Lee
20-Sep-2009, 07:02
Steven, yes it is an old idea and from my research it worked quite well then. Even Mathew Brady use one. As far as variable exposure is concerned, it is unnoticeable in the end results. If the unit is used vertical there is enough tolerance to void friction. Weight is no concern here. The slides are heavy enough to be constant. I have tried several versions and this one works best. I am working on a similar ideal that is controlled by an electronic timer that will be quite a bit smaller in size and weight. My first ideal was to use several slides with openings to correspond with the basic speeds, but that idea soon vanished when the cost was considered. I made one shutter for a 5 3/16" lens and the shutter was quite large, which led me to designing a smaller version. It will take a couple of months to get this one going. The guillotine shutters have all been large in size and heavy, which has been an inconvenience to the user. I try to make mine as light as possible, (4.5oz for the small one) If you have looked at the photos taken with these units you may agree that it's not bad for the cost. My original idea was to make something affordable and durable and accurate for the guys that had no other option and wanted to use a faster film. All ideals are appreciated.

Tintype Bob
6-Oct-2009, 07:10
I just spent this weekend with Ron and a few other great guys photographing in Kentucky and I got to see Ron's shutter first hand, it works great, attached is a photo he took of us with it.

Don7x17
7-Oct-2009, 08:29
I just spent this weekend with Ron and a few other great guys photographing in Kentucky and I got to see Ron's shutter first hand, it works great, attached is a photo he took of us with it.

Good to see another image showing that this works so well. As Ron says, its an older concept but it works very well.

I finally got the mounting finished on the coated Cooke lens mentioned and hope to post some images after using it (and Ron's shutter) this weekend ...give me a couple days after the weekend for develop and print 8x10 contacts.

Don7x17
13-Dec-2009, 15:14
If you'd like to see what Ron's shutter does on that huge lens (10+ pound coated Cooke 5+ inch diameter objective) you can see examples at:

All on Tmax 400 (TMY) 1/8 second shutter speed 5.6(wide open with soft setting just under halfway so its somewhat diffuse) - available light in Goldfield, Nevada, county courthouse -- at the Jim Galli/Per Volquartz Tonopah workshop

(model: Per Volquartz)

http://www.apug.org/forums/members/don12x20-albums-tonopah-picture2760-per-volquartz-420mm-cooke-soft-set-2-5.html

(model: Jim Galli)

http://www.apug.org/forums/members/don12x20-albums-tonopah-picture2883-jim-galli-cooke-lens-soft-set-2-5-ron-tinchner-shutter-1-8-sec-f5-6.html

(model: Harlan Chapman)

http://www.apug.org/forums/members/don12x20-albums-tonopah-picture2908-harlan-tmy-400-1-8-sec-5-6-thh-cooke-420mm-soft-set-2-5-ron-tinchner-shutter-front-mounted-scan.html

These are just negative scans, inverted -- the negatives are outstanding and Ron's shutter performed flawlessly.

Hugo Zhang
14-Jan-2010, 16:34
Anybody knows how to get hold of Ron? I have sent inquiry to both of his email accounts and have yet received any reply. I am interested in an adjustable device for lenses with 3" to 5 1/4" front diameters and a Lees filter slot attached.

Don7x17
15-Jan-2010, 22:50
Here's an image of the 8x10 camera, Ron's shutter on the THH Cooke Lens. Note the "Kentucky Shutter Release"(clothes pin)...it worked well.
This is the camera/lens/shutter that I used to make the images in post #76 on this thread.
Don

pemsRisaacins
25-Mar-2010, 00:48
A waistcoat slip as I know and seen is a white curved slip of fabric around 2" wide that is attached to the opening of the waistcoat so that it protrudes out around 1/4-1/2" like in the pic I posted and is attached using 6 buttons two at the back, two both sides of the fronts.