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Vibrations & the Contax 645

BradleyGibson

New member
I have.

The majority of this problem seems to be coming from the elasticity of the camera/lens combination itself. Even putting the system onto a vibration isolating table (scientific instrument) weighing a couple of hundred pounds didn't help with sharpness.

Today, the way I weighted the lens AND the camera gave a decent (but not ideal) result. I think eliminating the flex will be Job 1. Once that's done, damping the rest of the system should be pretty straightforward.
 

David Klepacki

New member
Bradley, from what you describe, you either have a decentered lens element, or you have a problem with your lens/body mount (or possibly both). Is the lens-body mount coupling rock solid, or is there some play? Any amount of play here could easily destroy the image quality. Also, a tiny lens registration distance error could show up as blur, since the effect could be like adding a tiny extension tube to the lens. Can you confirm infinity focus with the 350? If not, then you have a registration distance error (and could still have the other problems).

First, you should see if you can get a crisp image at very high shutter speed, like 1/2000. This will tell you just how much vibration is a factor. If this image is still not crisp, then your problem is one of the above, and not about shutter vibration. If it is crisp (corner to corner), then I would next tape a laser level to the camera and study the vibrations to see what is going on near the slower shutter speeds.

Also, if you have a 210 that delivers crisp images at the same f-stop and shutter speeds (and similar object range) whereas your 350 images are not crisp, then the problem is entirely with the 350 lens; otherwise, the body mount may also be at fault.

David
 

PeterA

Well-known member
Bradley - all your stuff is good.

and I agree with teh comments above re teh possibility of a flawed lens/lens mount. Also note that Jack refuses to shoot @ 1/15th with his gear as he sees thisis the single worst shutter speed in terms of vibration ertc.

3 variables ot consider - shoudl be easy for you to isolate.

Cheers.

Thanks, Peter.

>I have had now one too many lemons sold to me from OS - never gain I have no trust left. I have calculated that I hav espent over $3000 US over the last year - reparing stuff I bought from this forum....

Nothing of mine, I hope?
 

fotografz

Well-known member
Don't know if this will help ... that's one big lens and when I used it to do some pin registered stop action sequences (which shows up even the slightest movement when the images are layered and animated), I ended up hanging a saddle type shot bag over the lens near the center just above the tripod mount.
 

BradleyGibson

New member
David, by around 1/250th the lens is sharp. I'd like to shoot it high noon on a very bright day to go even faster at an aperture smaller than wide open. But from the limited testing I've done so far at fast shutter speeds, all this stuff seems to disappear.

Peter, yup, I agree with Jack--1/15th is probably the worst place to be shooting. (That's why I picked it, actually). If I can figure out how to get the shot to be pin-sharp at around 1/15th, every other shutter speed should be all the better for it. And good to know everything is working "just as advertised". :)

Thanks,
-Brad
 

Jack

Sr. Administrator
Staff member
Bradley,

One other issue you are dealing with that has not been specifically mentioned, and that is the magnification factor of the lens. Obviously the longer the lens, the more the vibration will be seen. I suspect you would see this same behavior at 1/8th - 1/30th with a 210, albeit less obvious than with the 300. HOWEVER -- and this is an important point -- most 300's have a tripod foot, and most 210's don't... With the lens hanging off the front of the camera, the point with the most tolerance (read slop) for movement is the lens-mount. With the lens unsupported gravity is your friend as it adds a downward vector that "tightens" the mount slop up. Moreover, the structure with the offending vibration -- the camera body -- is being directly supported which will reduce vibration due to a shorter moment vector (the shutter is almost directly over the point of support). Now mount the same system under the center of the lens, and all of a sudden there is 1) less mass on the lens-mount joint so it is "looser" (read sloppier), and 2) the area under the shutter is now unsupported, and at a distance from the point of support increasing the moment arm and magnifying motion.

So, here is something to try *IF* you need to shoot in the 1/8th through 1/30th speed ranges with the 300 (or any long lens on any camera system) regularly. Get a Bogen "Magic Arm" and clamp one end to a tripod leg about half-way down the top leg section. Attach the other end to your camera body's base plate. NOW place a sandbag over the lens close to the lens-mount and you should have far better results. (Unfortunately, it is more of a PITA to adjust this assembly quickly, but will probably solve your vibration problem with that lens...)

Magic arm kit, you'll need to add a QR clamp: http://www.bhphotovideo.com/c/product/325440-REG/Manfrotto_by_Bogen_Imaging_143_Magic_Arm_Kit.html

5 LB sand bag should be enough, but you could also fill it with lead shot for about 8 to 10 pounds: http://www.bhphotovideo.com/c/product/592391-REG/Impact_SBE5O_5_lb_Cordura_Sandbag.html

Cheers,
 
D

ddk

Guest
Bradley,

One other issue you are dealing with that has not been specifically mentioned, and that is the magnification factor of the lens. Obviously the longer the lens, the more the vibration will be seen. I suspect you would see this same behavior at 1/8th - 1/30th with a 210, albeit less obvious than with the 300. HOWEVER -- and this is an important point -- most 300's have a tripod foot, and most 210's don't... With the lens hanging off the front of the camera, the point with the most tolerance (read slop) for movement is the lens-mount. With the lens unsupported gravity is your friend as it adds a downward vector that "tightens" the mount slop up. Moreover, the structure with the offending vibration -- the camera body -- is being directly supported which will reduce vibration due to a shorter moment vector (the shutter is almost directly over the point of support). Now mount the same system under the center of the lens, and all of a sudden there is 1) less mass on the lens-mount joint so it is "looser" (read sloppier), and 2) the area under the shutter is now unsupported, and at a distance from the point of support increasing the moment arm and magnifying motion.

So, here is something to try *IF* you need to shoot in the 1/8th through 1/30th speed ranges with the 300 (or any long lens on any camera system) regularly. Get a Bogen "Magic Arm" and clamp one end to a tripod leg about half-way down the top leg section. Attach the other end to your camera body's base plate. NOW place a sandbag over the lens close to the lens-mount and you should have far better results. (Unfortunately, it is more of a PITA to adjust this assembly quickly, but will probably solve your vibration problem with that lens...)

Magic arm kit, you'll need to add a QR clamp: http://www.bhphotovideo.com/c/product/325440-REG/Manfrotto_by_Bogen_Imaging_143_Magic_Arm_Kit.html

5 LB sand bag should be enough, but you could also fill it with lead shot for about 8 to 10 pounds: http://www.bhphotovideo.com/c/product/592391-REG/Impact_SBE5O_5_lb_Cordura_Sandbag.html

Cheers,
I've tried the magic arm, but the combination is too restrictive for me in the field and I wont even open my mouth regarding the sand/lead bags. I don't know what most of you want to shoot with this lens but I find majority of the solutions here unrealistic for real situations, at least in my realm when I have a need for such a lens. Personally, I like to be able to freely compose and recompose on the fly while looking through the finder and all these extra accessories simply get in the way. I haven't tried shooting with this lens at higher shutter speeds (1/1000th+), I will once it stops raining here in NY. I hope that it works properly, if not the lens will join the long list of wonderful gadgets I've collected over the years but have no use for. Then I'd rather use the 210mm with a high mp back that has a crop factor like the new P40+ and crop a bit if necessary, a more realistic solution imo and much lighter on your back too when going up the mountain.
 

Jack

Sr. Administrator
Staff member
David,

Agreed, but as I said above,

"*IF* you need to shoot in the 1/8th through 1/30th speed ranges with the 300 (or any long lens on any camera system) regularly."

and

"(Unfortunately, it is more of a PITA to adjust this assembly quickly, but will probably solve your vibration problem with that lens...)"

:),
 
D

ddk

Guest
David,

Agreed, but as I said above,

"*IF* you need to shoot in the 1/8th through 1/30th speed ranges with the 300 (or any long lens on any camera system) regularly."

and

"(Unfortunately, it is more of a PITA to adjust this assembly quickly, but will probably solve your vibration problem with that lens...)"

:),
Unfortunately I've seen the vibration issue even at 1/500!
 

Jack

Sr. Administrator
Staff member
I believe it. I never owned the 300 when I shot my Contax, but I had a similar problem with Nikon and a 600 f4 and in the end simply gave up and sold the lens. Interestingly and getting back to MF, I have owned the 300 with the Mamiya AFD3 and can confirm it was *NOT* a huge issue with that combo, even at 1/15th which I purposely tested...

FWIW,
 

Greg Seitz

New member
At what point does it make sense just to haul something like a 5D MkII and a 300mm F/4 lens rather than all the pain involved in hauling this and all the support neccesary to get a decent shot?

You could haul all your existing kit and still come out ahead weight wise - something like 5lbs for a canon system vs 8lbs for the contax lens. It seems unlikely from what you've shown that you'd end up with any more resolution in the end with Contax lens.
 

Guy Mancuso

Administrator, Instructor
I think maybe even just a simple bean bag approach maybe worth looking into trying. Just get a nice big bean bag about 8lbs get everything setup and just lay that on top of lens over the tripod head section area and just settle everything down. A lot of this depends on the mounting off all this . I like the lens tripod mount the best as it balances things out
 

David K

Workshop Member
Got a chance to test out my kit... Contax 645 with 350 SA via Mam-1 adapter. Shot at 1/15th on tripod with top section of legs extended. No weights and just pressed the shutter. The first image is color corrected and sharpened. Looks pretty good to me...YMMV.
 

David K

Workshop Member
David (no offence)- i dont think the first image ( or any image in fact) is sharp.
None taken Pete, it's not sharp. I do think it's a bit sharper than Brad has gotten with his lens and posted it more to show him what I was getting. I really have no occasion to shoot at this shutter speed with a telephoto lens so the results don't particularly bother me. If I want sharp tele shots I get everything I need from the Nikon 300 2.8VR and a whole lot less hassle.
 
J

jp mcgraw

Guest
Bradley,

I was recently doing a test with my Contax 645 and the 350 f4 and had the same problem that you have encountered. While I did not solve the problem, I remembered an article I read on the Luminous some time ago that talked about a stabilizing bar that attached to the base of the camera and fastened to one of the tripod legs in situations where the lens is mounted directly on the tripod head. I thought this might work. If I can find this , I'll let you know.

Regards,
John
 

BradleyGibson

New member
David, the intriguing thing to me is that I don't see *vibration* in your 350SA images, with the same model camera and same amount of magnification. Hmmm... Thank you for posting them.

John (and others), while I've pretty much ruled out the tripod-leg based stabilizer (too difficult to recompose, clumsy and slow to set up), I have two plans of attack:

1) Find/create a rail to which both the camera and lens foot will attach. Mount this rail on the tripod head and see if the added rigidity resolves my problem.

2) Look at a head with fluid damping - apparently this can make a big difference--Dr. Kornelius Fleischer (Mueller) formerly of Zeiss wrote about issues like this. Note that the one he refers to here costs ~$3000 and weighs 6kg--yes for a head! Obviously not a viable solution for me... Let's hope I can solve this with #1, above... FWIW, here is what he wrote in Camera Lens News back in 1998 (obviously, a film-centric guide):

--

10 Steps to success in high performance photography

The following article is meant to be a ten step guide to images that are significantly sharper than average ones. Images that exploit the enormous optical potential of Carl Zeiss lenses, their ability to produce photos with phenomenal sharpness and impressive information content. This is the ten step method used by Carl Zeiss applications specialists to shoot the high resolution demo photos which challenge today's sharpest color films to their very limit.

1.
Select a high performance optic! If you don't, all subsequent steps are a waste of your time and effort.

2.
Attach your high performance optic to an adequate camera. To be adequate, the camera needs to have an all metal die cast housing, strong and large bottom plate with tripod thread preferably located under the center of gravity. If the camera has a detachable winder or motor attached underneath, you may want to take it off for better rigidity of the whole system. Do not simply assume that your camera is in perfect condition, rather have it double checked for correct back focal flange distance, and – in case your camera is an SLR – for perfect alignment of mirror and focusing screen in relation to the film plane.

3.
Place your camera and optic in a very rigid way onto a very stiff tripod and head, preferably with virtually no elasticity. Photo tripods usually prove insufficient for real high performance photography.

You may wish to use a carbon fibre television tripod instead, with a fluid head featuring adjustable damping devices. Balance your camera properly on the fluid head, adjust the counterbalance dial for the weight of your camera and lens, choose high values on the damping system dials (e. g. 5 to 7 on a Sachtler "Video 18 Plus"), and do not fasten the brakes! This is the special trick with fluid heads: Use their damping systems, originally invented to enable the cameraman to perform smooth pans, to absorb equipment vibrations triggered by the shutter, instead. These vibrations could otherwise reduce or even destroy the optical resolution of fine structures.)

4.
Select a high performance film like Kodak Ektar 25 Professional or Kodak Royal Gold 25 (color negative), or Kodak Technical Pan (black & white) or Fuji-chrome Velvia (color transparency) and make sure it will be processed adequately. Films like the ones just mentioned offer a resolving power of 150 line pairs per millimeter and beyond.

5.
Use the split field indicator for focusing. Make sure the aperture is wide open. You may want to use accessories – small telescopes like the Carl Zeiss MiniQuick® 5 x 10 T* with 5x magnification are pretty handy for this task – to enlarge the center of your viewfinder image during focusing.

6.
Prefer f-stop settings in the region of 5.6 to 8. (To close the aperture down further will cost too much resolution due to the unavoidable phenomenon of diffraction (At f/8, diffraction will limit the resolution to 200 line pairs per millimeter or below, at f/5.6 the diffraction limit is at 280 line pairs per millimeter; see CLN 2). To open up the aperture more may cost too much resolution due to thermal expansion effects, film curvature due to moisture and temperature (The Real Time Vacuum System in the Contax RTS III does away with this problem). Mechanical tolerances due to wear and tear, rough handling and other influences like residual warpage of the focusing screen also recommend to open up no wider than 5.6 or 8.)

7.
Use the mirror pre-release feature, if your camera has it (Every camera that has it, needs it. The opposite is not true! Not every camera that comes without, can achieve high resolution photos.)

8.
Wrap your hands around the camera to absorb most of the vibrations that occur upon opening the focal plane shutter (you may not need a cable release at all). If your camera system gives you the freedom to use either focal plane or central shutter – like the Hasselblad 200-series cameras or the discontinued Rolleiflex SL 66, when combined with central shutter lenses – prefer the central shutter because of its inherently lower vibration levels.

9.
Take written notes of all parameters and settings (like: "Carl Zeiss Distagon 28 mm # 7.500.123, @ f/8, Contax RX # 10.531 @ 1/125, in Av-mode, Mar 3, 1998, focusing done with split field indicator for license plate in center of image, damping on fluid head: 7 on vertical, 5 on horizontal, license plate on truck 350 feet away, character line width on license plate: 3/8 inch.")

10.
Select a lab that is very quality conscious about equipment and materials and uses high performance optics in printers and enlargers. The best optics ever used in a lab for enlarging are Carl Zeiss S-Orthoplanar 4/60 and Carl Zeiss S-Biogon 5,6/40 for prints from 35 mm originals and Carl Zeiss S-Orthoplanar 5,6/105 for prints from medium format originals. These optics were originally developed for the extreme resolution demands of microdocumentation (beyond 150 line pairs per millimeter) and are, at magnifications of 10 x to 70 x, far superior to even the very best enlarging lenses currently available.


Understanding and using these techniques will surely give you a better appreciation of the extremely high limits which Carl Zeiss has spent so much effort designing and manufacturing into their lenses. More than ever before, extremely careful and deliberate technique must be
used to obtain the results of which the equipment is capable.

Carl Zeiss Camera Lens News No. 4, spring 1998
 
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gogopix

Subscriber
Any vibrating system is going to blur, ans with a 6 micron sensor it doesnt take much. Wind on the lens, or vibration thru the floor. Yes, the mirrow will slap, but is well damped.
Tools need to be used as designed, and I never expected a 350mm lens, with its size and 'optical lever' was going to require anything less than TOTAL damping (lens and camera) or isolation.

In the following I used my 350mm/ f4 Contax at f4 and iso 50. That got me to 125s not as low as the 1/15 above, but it was enough to show blur

and how to stop it!

In order
1. the scene
2. 2s delay (mirror up) with a good tripod mount
3. 2s shutter using the manfrotto on the camera and the lens forward on mount for max stability
4. The way I would normally ake the shot! 1000s :salute:
5. A little help, that is all above were unprocessed and unsharpened. Here a little exposure boost and smart sharpen (I think 49%)

2-5 are 100% crops of a 60MP image

I think you click on the image to get the full size
 
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PeterA

Well-known member
Bradley - fascinating reading - especially the bit about using specialist tripod mounting.

My 300MM HC arrives in the next day or so..I will make some tests using it as is as well as with the 1.7X extender. I have given up trying to use my FE 250F4 with or without 1.4X extender on a 200 series body - the mirror slap is ungovernable..-:) I await Son's delivery of a Contax body to test.

As a side note - many may not be happy to hear that the 645 Mamiya body (ahem) does not have as good engineered infrastructure in it - to fine tune focus as other body types.

Victor - all i can see with yoru 'fixed' crop is totally blown highlights....but impressive detail in the non cropped shot - even on a screen.
 
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