Pentax 67 owners, my "ttl chain" does not look like a chain...help please

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moodlover

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For this reason, and this reason alone, you should send the camera back. The camera is NOT AS DESCRIBED. There have been modifies repair(s) done to the camera that were not disclosed, whether or not the seller knew about it. Without the chain, it is no longer a 'Pentax 6x7', it's a 'Modified Pentax 6x7'.

It may end up that the modification is perfectly acceptable, which you will (mostly) know once you try a lens on it, but while you're waiting for the lens, you need to file an INAD case with ebay. If nothing else, it gives you extra time. Ebay gives you about a week to ship it out, so if you wait until the second to last day of the return period, it'll give you extra time. If after trying it out with a lens (extensively), and you decide to keep it, you cab always just not send it back.

One other thing to keep in mind is the value of your peace of mind. At some point in the future, whether it's in 30 days, or 30 years, that cable may/will break. And when it does, you'll be saying to yourself you shouldn't have kept it...
Yes this is a great idea, I'll have to open a return case before the time runs out while I wait for the lens to arrive and test some rolls out. Hopefully everything works out in time, thanks for the idea.
 

aoresteen

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What would it cost me for Eric to overhaul my camera? ....

Thank you check.[/B][/I][/h]

Email him with photos. Most likely he will want to examine the camera. There might be more wrong with it inside that you can not see.

www.pentaxs.com
 

StephenT

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The repair MAY be a good one. I would test it with a lens attached - that chain is a weak point, in my opinion, and I feel fortunate that none of mine have broken as yet!
 
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Email him with photos. Most likely he will want to examine the camera. There might be more wrong with it inside that you can not see.

www.pentaxs.com
I wasn't game enough to say those last few words, but I hope that is certainly not the finding. [emoji6]

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moodlover

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Well we shall see, lens will arrive tomorrow or Wed, then I will have a test shoot outdoors and have a lab look at the results. What exactly am I supposed to do? I will shoot different apertures in order from 2.4-2.8 - 4 - 5.6 - 8 - 11 -16 - 22 on the 105mm lens. But should the shutter speed compensate so all frames match exposure (guessing the TTL meter should always point to the middle of the plus and minus?) Or should shutter stay the same and allow less light in each following frame? Never done a camera test before, thanks for the advice!!
 
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SMBooth

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Even without a len you should be able to tell if its OK, remove the prism, just put your finger on the tab in the lens mount (about 10 oclock position), make sure there is no play. It should be that as you start moving the tab the little black plastic bit which makes contact with the prism moves. I should be smooth and allow the tab to move within about 8 mm on the left side (from front). Simple
 
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Well we shall see, lens will arrive tomorrow or Wed, then I will have a test shoot outdoors and have a lab look at the results. What exactly am I supposed to do? I will shoot different apertures in order from 2.4-2.8 - 4 - 5.6 - 8 - 11 -16 - 22 on the 105mm lens. But should the shutter speed compensate so all frames match exposure (guessing the TTL meter should always point to the middle of the plus and minus?) Or should shutter stay the same and allow less light in each following frame? Never done a camera test before, thanks for the advice!!


It's as much about testing the lens as it is the camera. For instance, you need to be sure the aperture blades are not sticking or there is something else not working well. I am in favour of testing the camera with a lens attached, to highlight possibly other problems you may not be aware of, quite aside from the TTL meter coupling chain that may be fine as it is. One of these problems is derangement of the TTL meter due to its age. That is to say, indicated exposures are off by some sort of measurement. If this happens, it's not the end of the world. Use a separate hand-held incident or multi-spot meter (my choice entirely to bypass the TTL meter). Other problems are deterioration in accuracy of shutter speeds, lazy/slow reflex mirrors, peeling of tape from shutter curtains and corrosion of the battery compartment.

The TTL meter has a 5-stop range. The dead centre is correct exposure, and will level out either with a tweak of the shutter speed or the aperture (most SMC Pentax 67 lenses have half-stop clicks). Above and below the centreline is 2 stops; with experience you will be able to tell the approximate position of Zero, +1, +2 and Zero, -1, -2. Exposing fussy transparency film e.g. Velvia 50 can be done like this, assuming you are using the film in the conditions for which the film was intended.

I think you should run a roll of transparency film through the camera. This film has a narrower tolerance for under- and overexposure, and will show gross exposure errors much easier than say print film with a wider latitude. You must take notes of your exposures during the test so you can launch a critical examination of the images when they are back from the lab. I am not going to pre-empt any finding at this stage but I would be interested in knowing how the test goes. A lot of Pentax 6x7 and later 67 bodies are now quite old (including mine). How they have been used and looked after says a lot in their later years and deterioration in functional accuracy does occur over time. You won't of course find out anything useful until a full round of tests with the lens have been carried out. Then come back and tell us about it!
 
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moodlover

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@Poisson: thanks for all the help, I will shoot the test roll today and show the scan results here. As far as I can tell, the blades seem very smooth when I use the depth-of-field preview switch to stop down the blades. The needle on the prism is definitely working now, and but unfortunately seems to be 4 stops under from my incident meter (and Canon 5D Mark III's meter which is very accurate and identical to the Sekonics reading)...

Sekonic L-358 ambient reading:
ISO800, F/4.0, 1/80

Pentax 67 TTL prism of same scene until meter is in the middle:
ISO800, F/4.0, 1/4

Video of this test: https://vid.me/e/z7LU

I would say this is enough to justify a return yes? If anything, I may ask the seller for a partial refund so I can keep the camera and use the money towards the repair perhaps. This has not been a pleasant experience for me, I was looking forward to having a reliable TTL prism for outdoor shooting because this camera is heavy and enough to carry as is...what do you guys think I should do?
 
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@Poisson: thanks for all the help, I will shoot the test roll today and show the scan results here. As far as I can tell, the blades seem very smooth when I use the depth-of-field preview switch to stop down the blades. The needle on the prism is definitely working now, and but unfortunately seems to be 4 stops under from my incident meter (and Canon 5D Mark III's meter which is very accurate and identical to the Sekonics reading)...

Sekonic L-358 ambient reading:
ISO800, F/4.0, 1/80

Pentax 67 TTL prism of same scene until meter is in the middle:
ISO800, F/4.0, 1/4

Video of this test: https://vid.me/e/z7LU

I would say this is enough to justify a return yes? If anything, I may ask the seller for a partial refund so I can keep the camera and use the money towards the repair perhaps. This has not been a pleasant experience for me, I was looking forward to having a reliable TTL prism for outdoor shooting because this camera is heavy and enough to carry as is...what do you guys think I should do?



The P67 meter is responding correctly when you alter the shutter speed. There is also the real risk of extraneous light entering the unprotected viewfinder (where is the viewfinder eyepiece cowl?).

Looking at the scene there, the Sekonic should be balancing the light from left and right of the key subject (the orange, 2+ readings, averaged). I suspect the P67 will only see a bright spectral and potentially underexpose the scene.

Re your comparison of readings with the Canon. The small discrepancy in metering can be due to the rudimentary centre-weighted area metering of the Pentax 67 as opposed to the modern 3D-evaluative metering of the Canon, which takes into consideration the scene's contrast and brightness in terms of layers of depth, while the P67 has no such intelligence — it doesn't know what it is looking at, and further more, it doesn't care! The Sekonic would need to be read at several points in the scene rather than just held out at arm's level with a single reading.
 
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moodlover

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The P67 meter is responding correctly when you alter the shutter speed. There is also the real risk of extraneous light entering the unprotected viewfinder (where is the viewfinder eyepiece cowl?).

Looking at the scene there, the Sekonic should be balancing the light from left and right of the key subject (the orange, 2+ readings, averaged). I suspect the P67 will only see a bright spectral and potentially underexpose the scene.

Re your comparison of readings with the Canon. The small discrepancy in metering can be due to the rudimentary centre-weighted area metering of the Pentax 67 as opposed to the modern 3D-evaluative metering of the Canon, which takes into consideration the scene's contrast and brightness in terms of layers of depth, while the P67 has no such intelligence — it doesn't know what it is looking at, and further more, it doesn't care! The Sekonic would need to be read at several points in the scene rather than just held out at arm's level with a single reading.
The viewfinder eyepiece and cowl/hood were removed only for the purpose of the video and did not affect this reading. I see what youre saying about the Sekonic reading the light with the dome and the P67 underexposing the scene, but 4 stops is ridiculous dont you think? I tried in different corners of the room, different rooms with no harsh lighting, and the P67 performed the same every time: grossly underexposed compared to the handheld meter.

Anyways, youre saying theres a possibility the P67 is metering fine for what it is...but how can I test that more? Im out of ideas and not sure why it would be 4 stops off. 1 stop I can understand but 4...

Edit: starting to remember what you said about it only having a 5-stop range of reading...so -4 or -3 wouldn't even register on the meter meaning maybe it's not 4 stops off...but im still unsure about why 1/4s would center the needle and not 1/60s

Edit 2: the seller has responded to my findings and asking him if he wanted to offer any solution before I open a return:

Matter of goods, sorry.

Please let us know you'd like to make you what.

We will do my best so that the problem can be resolved.
Open the case to eBay, it would be appreciated wait.


I guess this means "oh well, do what you will"?
 
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The viewfinder eyepiece and cowl/hood were removed only for the purpose of the video and did not affect this reading. I see what youre saying about the Sekonic reading the light with the dome and the P67 underexposing the scene, but 4 stops is ridiculous dont you think? I tried in different corners of the room, different rooms with no harsh lighting, and the P67 performed the same every time: grossly underexposed compared to the handheld meter.

Anyways, youre saying theres a possibility the P67 is metering fine for what it is...but how can I test that more? Im out of ideas and not sure why it would be 4 stops off. 1 stop I can understand but 4...

Edit: starting to remember what you said about it only having a 5-stop range of reading...so -4 or -3 wouldn't even register on the meter meaning maybe it's not 4 stops off...but im still unsure about why 1/4s would center the needle and not 1/60s

Edit 2: the seller has responded to my findings and asking him if he wanted to offer any solution before I open a return:

Matter of goods, sorry.

Please let us know you'd like to make you what.

We will do my best so that the problem can be resolved.
Open the case to eBay, it would be appreciated wait.


I guess this means "oh well, do what you will"?

Run a roll of Provia 100F transparency film through the 67. Shoot in both bright daylight and overcast/soft light and vary the ISO up to EI125 and down to EI80. Use all apertures on the lens, and as many shutter speeds as you can and level the TTL meter reading. Record notes for each exposure. Reason for transparency film is that gross under- or over-exposure will be very evident without doubt, while print film could very well mask such errors. I should also mention that the Pentax 67 native TTL meter copes very well with contrasty situations, and that means from my experience it has no great trouble finding the midline exposure in less than ideal conditions with e.g. Velvia 50. If the exposed film (10 exposures) shows a lot of errors (including but not limited to frame spacing errors), get rid of the camera right then. Just tell the seller you have some well-founded (and hopefully soon-proven) concerns, and need to test the camera's exposure accuracy explicitly to remove any doubt. The seller's poor grasp of English is a pox. Things could potentially get difficult if he bucks and sways so do everything now in good and proper time.

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Serendipia

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I bought this off eBay in great condition and I took off the TTL finder to inspect the chain of the Pentax 67 (416xxxx serial). It doesn't have any links that look like a chain, instead it just looks like a thin wire:

attachment.php


Please tell me if this is abnormal and if I should return this to the seller. The item described this as fully functional and near mint condition so I am not sure why this chain is not a chain...here is what a google images search shows the Pentax 6x7s one (which isn't the 67 but I assume the chain should be the same):


attachment.php


Thoughts?!
Hello, I have a 6x7 with a broken chain. I use a light meter. It's that simple. If the camera is good and you like it, the light meter is the least of your problems. Sooner or later (if you don't already) will know light and how to translate that into numbers. There is a very good App out there called Cine Meter. This link is for the Cine Meter 2 but the plain original 6-7$ version is just as good for your purposes. In fact better than the meter your 67 has. Had. http://nofilmschool.com/2014/07/cine-meter-ii-app-replace-light-meter. An other thought; Seeing the repair job on your camera; all you have to do is not remove the TTL prism before you unmount your lens. 2) Why you'd remove the prism is beyond me as I've never one had to in 27 years except when I decided to replace the seals. 3) just test run a few rolls and if you notice the meter being off a bit, compensate. I always loved a camera with an attitude. I like my friends that way too :smile: Just to be sure you know; I'm not being flippant, I take your issue to heart, but seriously, it's not a big issue, and once you decide to look at it an other way you may even get a kick out of it. Enjoy it, you'll love it
 
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