How big of an issue is mirror slap on Pentax 6x7 (thought I was getting MLU, but...)

[-persimmon-tree-]

Hi everyone,

I have a new Pentax 6x7 that I'm taking my first few rolls on. Test roll is already being developed, but I"m shooting another more serious roll now. The ebay listing specifically says "mirror up" in it, and I didn't know enough about the camera to look for the mirror up button, I just assumed that was right. Today I was taking an indoor shot and metered for 1/8 of a second at f8. I figured that was slow enough that I should use the mirror lock up, but I couldn't find the button anywhere. Do some research and find out that it's definitely not there.

I reached out to the seller to see if they'll give me a partial refund for the false advertising (they were very responsive before, so we'll see). I really don't want to have to deal with the hassle of shipping this thing all the way back to japan, and the camera is in excellent condition aside from this. So I wanted to ask, how big of an issue is the mirror slap? I'm not going to be blowing up photos massively or anything, and I'm honestly not a huge perfectionist. But I do shoot often at low-ish speeds, like 1/125 to 1/4. I use a tripod and cable release always. Is it at the point of being completely not worth it? Obviously I'll see for myself when my rolls come back, but by then it'll be late enough that I won't be able to return the camera normally, so I figured I'd check.

I'll also add that the seller offered to refund me $50, and I got it by making him a $50 lower offer than the listing. This means I'll have gotten the camera for $550 plus shipping. The body and lens are in extremely good condition by my inspection. This seems worth it to me and from my reading, the MLU isn't a horrible all-the-time issue, but more like "something to be aware of". Anyways, look forward to hearing some wisdom from those with more experience than me. Thanks!

Thanks!

 

[RalphLambrecht]

Hi everyone,

I have a new Pentax 6x7 that I'm taking my first few rolls on. Test roll is already being developed, but I"m shooting another more serious roll now. The ebay listing specifically says "mirror up" in it, and I didn't know enough about the camera to look for the mirror up button, I just assumed that was right. Today I was taking an indoor shot and metered for 1/8 of a second at f8. I figured that was slow enough that I should use the mirror lock up, but I couldn't find the button anywhere. Do some research and find out that it's definitely not there.

I reached out to the seller to see if they'll give me a partial refund for the false advertising (they were very responsive before, so we'll see). I really don't want to have to deal with the hassle of shipping this thing all the way back to japan, and the camera is in excellent condition aside from this. So I wanted to ask, how big of an issue is the mirror slap? I'm not going to be blowing up photos massively or anything, and I'm honestly not a huge perfectionist. But I do shoot often at low-ish speeds, like 1/125 to 1/4. I use a tripod and cable release always. Is it at the point of being completely not worth it? Obviously I'll see for myself when my rolls come back, but by then it'll be late enough that I won't be able to return the camera normally, so I figured I'd check.

Thanks!

There are other ways to deal with mirror slap in case it becomes an issue. A good tripod and a cable release are a good start.

 

[-persimmon-tree-]

There are other ways to deal with mirror slap in case it becomes an issue. A good tripod and a cable release are a good start.

I am using those already. What I'm wondering is if it's likely to be a serious issue even if I use a tripod and cable release.

 

[Alan9940]

I’ve only ever owned the P67 (with MLU) and now the 67II, but my guess is that even on a good tripod you might notice some sharpness degradation at slower shutter speeds. How slow? I’d say anything below 1/60 second; at least, that’s what my own testing of this very question proved many years ago with my P67.

I agree with Ralph, that a good (read solid, heavy) tripod and cable release will be your best bet to mitigate this issue, if you see it. Whether you even notice it or not will depend on how critical you are and how big you plan to print. Other things you might try is hanging some weight below the apex of the tripod and definitely DO NOT EVER raise the center column of the tripod, if it has one. You’ll need a good, solid, beefy tripod head, too. If you’re starting to think that everything about using a P67 requires heavy stuff, you’re on the right track!

 

[-persimmon-tree-]

I’ve only ever owned the P67 (with MLU) and now the 67II, but my guess is that even on a good tripod you might notice some sharpness degradation at slower shutter speeds. How slow? I’d say anything below 1/60 second; at least, that’s what my own testing of this very question proved many years ago with my P67.

I agree with Ralph, that a good (read solid, heavy) tripod and cable release will be your best bet to mitigate this issue, if you see it. Whether you even notice it or not will depend on how critical you are and how big you plan to print. Other things you might try is hanging some weight below the apex of the tripod and definitely DO NOT EVER raise the center column of the tripod, if it has one. You’ll need a good, solid, beefy tripod head, too. If you’re starting to think that everything about using a P67 requires heavy stuff, you’re on the right track!

Good answer, thank you! My work doesn't tend to rely on extreme sharpness (I like using grainy film anyways, and I like higher resolution for being able to deal with more layering and more small subjects, not necessarily for more total sharpness if that makes sense. Not going to be printing huge at all, ever).

I read somewhere online that shake tends to occur between the prism and the body and that pressing down lightly on the prism when shooting can help. Did a test earlier today with two shots, one with that and one without -- we'll see in due time. I might sacrifice a roll entirely to testing sharpness this way, although without ND filters it may not be a perfect test. Still, I'll try it, because I assume like with many old things, it also depends on the camera.

I think it won't be a big enough issue that I'll have to actually change the camera, especially given the price I got it, I'll make it work as best as I can. I am more worried about visible shake and blur rather than a slight loss of sharpness. Thanks for your help.

 

[Ian Grant]

When you hand hold a medium format SLR you dampen the effects of mirror slap. Surprisingly, it's more of an issue when using a tripod, when I started using my Mamiya 1000s for landscapes (on a tripod) I noticed some images were not as sharp as expected., I began always using the mirror lock. A lot depends on the shutter speed being used.

Ian

 

[DREW WILEY]

Mirror lock-up is important at shutter speeds slower than 1/60th. At higher speeds, the shutter will have already opened and closed before the mirror hits. Of course, a great many successful pictures were made with early P67's prior to the lockup feature. So a lot depends on how well supported the camera is. You want a solid, vibration-free tripod and head, especially for telephoto lens work. For handheld shooting, you're going to use shorter lenses and higher speeds anyway.

If you can afford one, I recommend a serious wooden tripod; these dampen vibrations better; and avoid ball heads like the plague.

 

[mtjade2007]

I have used my p67-ii since 2002 and more than 100X 220 rolls of film through it. I don't recall ever got a single bad shot caused by mirror slap. I only use the P67-ii handheld. In fact I don't remember ever got any blurred shot due to hand shaking either. On the other hand, I have had far too many bad compositions and bad processing of my films. The mirror slap issue has been the least concern to me when using this camera. If you need to shoot at slow shutter speed you can use the MLU. You should do so regardless what camera you use anyway.

 

[Alan9940]

I read somewhere online that shake tends to occur between the prism and the body and that pressing down lightly on the prism when shooting can help.

The issue primarily stems from the mirror raising up and "slapping" the underside of the prism/body housing. Pentax tried to mitigate this a bit in the 67II. But, sharpness degradation can also happen from the shutter itself due to how large it is. This somewhat depends on the lens used. For example, I had a friend years ago that had a P67 who liked to use the 300mm lens quite a bit. He always used MLU, regardless of shutter speed used. One day...just for the heck of it, he bolted the camera to a heavy tripod and did a test shooting power line towers and power lines at infinity focus. He used a high enough shutter speed to, one would think, eliminate any issues due to vibrations. A few exposures were made without MLU, while a few others were made with MLU. He wasn't expecting the non-MLU images to be usable, but he was very surprised to see that even the images where MLU was employed revealed image degradation due to vibration. The only thing moving internally was the shutter!

All that aside, I know of several photographers who make very nice images with the P67 handheld. I wouldn't worry about it and just enjoy your camera! Good luck!

 

[-persimmon-tree-]

The issue primarily stems from the mirror raising up and "slapping" the underside of the prism/body housing. Pentax tried to mitigate this a bit in the 67II. But, sharpness degradation can also happen from the shutter itself due to how large it is. This somewhat depends on the lens used. For example, I had a friend years ago that had a P67 who liked to use the 300mm lens quite a bit. He always used MLU, regardless of shutter speed used. One day...just for the heck of it, he bolted the camera to a heavy tripod and did a test shooting power line towers and power lines at infinity focus. He used a high enough shutter speed to, one would think, eliminate any issues due to vibrations. A few exposures were made without MLU, while a few others were made with MLU. He wasn't expecting the non-MLU images to be usable, but he was very surprised to see that even the images where MLU was employed revealed image degradation due to vibration. The only thing moving internally was the shutter!

All that aside, I know of several photographers who make very nice images with the P67 handheld. I wouldn't worry about it and just enjoy your camera! Good luck!

My reading did report that higher focal length makes this more relevant; I'm using a 75mm, so hopefully it'll be alright! Thank you for the encouragement

 

[DREW WILEY]

Alan - I have both an older 300mm for the P67 (same as the original Takumar optics) and the significantly improved EDIF version. Those lenses have a lot of sheer mass. And especially as I use them, right atop a large Ries wooden tripod (no tripod head), and yes, any potential vibrations are seriously dampened. I still employ MLU whenever possible.

But I've also simply rested the camera atop a jacket or hat on a car roof or fence railing, and shot it without MLU with excellent results. It's still firmly supported and well dampened. That's the key. The worst scenario is a flimsy underbuilt tripod and head.

Handheld, the optional hardwood grip adds a little more mass to the bare camera, and potentially helps. In terms of lens focal lengths, anything from 105mm down is fairly easy to manage handheld. The 75/4.5 is a superb optic, but hard to focus in dim light without an accessory magnifying eyepiece. The alternative 75/2.8 is awfully expensive. No problem if your subject is at infinity, however.

 

[Alan9940]

Drew - Thanks for the encouraging words regarding the 300mm focal length on the P67 as I've looked longingly at the EDIF version several times, but just never pushed the buy button. I guess I've always been hesitant about it due to my friend's experience. But. I agree that it requires more care to get acceptable results.

 

[RalphLambrecht]

Mirror lock-up is important at shutter speeds slower than 1/60th. At higher speeds, the shutter will have already opened and closed before the mirror hits. Of course, a great many successful pictures were made with early P67's prior to the lockup feature. So a lot depends on how well supported the camera is. You want a solid, vibration-free tripod and head, especially for telephoto lens work. For handheld shooting, you're going to use shorter lenses and higher speeds anyway.

If you can afford one, I recommend a serious wooden tripod; these dampen vibrations better; and avoid ball heads like the plague.

Good point by Drew! Dampening the vibration with a good wooden tripod or standing the tripod on sand or bean bags dampens the vibration and limits the mirror slap.

 

[guangong]

Don’t people read manuals anymore? Manuals for just about every modern camera is available on the internet, often free of charge. Generally, cameras are like dragons, if you’ve seen one you’ve seen them all, but still each camera can have its quirks.
When I acquire any unfamiliar used camera, I try to find a manual.

 

[Danner]

IME, medium format cameras need to be on a tripod with MLU to achieve the sharpest images. Even my Mamiya 7 performed much better on a tripod (obviously no MLU). The Pentax 67 in particular has real challenges when handheld. Currently, I use a Bonica GS-1, on a tripod, with MLU, and a shutter release cable. With that, it produces amazingly sharp images.

 

[DREW WILEY]

Alan - the nice thing about the 300 EDIF is that it has two tripod attachment points - both on the camera body itself, as usual, plus an effective rotating lens collar. I generally use both of these at the same time, via a uniting hardwood/phenolic laminated bar. This in turn is bolted directly to the platform top of either my larger Ries wooden tripod or a large Feisol CF tripod. In other words, there is no intervening tripod head. This works quite well, and I'm perfectly comfortable aligning the shot via leg movements only, since that has been my routine practice for view cameras for decades.

This is a superbly corrected lens capable of consistently precise exposures. But it does focus past the infinity mark. Perhaps astrophotographers could explain why. So I recommend a flip-up fine focus accessory magnifier with it, even for infinity work.

Every single "sharpness" complaint I hear about this lens seems to be due to an insufficient tripod support and wobbly head. It's a whole different ballgame than shooting with the regular 200mm and shorter length teles.

 

[loccdor]

Medium format focal plane shutter SLRs tend to vibrate even on tripods between 1/60-2 seconds.

What I tend to do is use a 9 stop ND filter if putting the aperture to f/22 isn't enough to get me past 2 second exposures. The vibration won't have much effect at those long speeds.

Or you can spend a ton of money on a very stable heavy tripod.

 

[DREW WILEY]

But what will be the penalty to the resolution and hue quality of that 9-stop ND filter? The good ones don't come cheap, especially in 82mm diameter. With black and white, it's easier to use a slower film and a deep contrast filter. And one can never go wrong investing in a sturdier tripod. I use the same tripods for my 300 mm P67 lenses as I do for my 8x10 camera. Simply slowing the exposure way down makes the scene and the gear itself far more susceptible to wind gusts. Otherwise, yes, there is more than one way to skin a cat.

Short on money? Simply convert a wooden, fiberglass-clad survey tripod from its 5/8-11 turnbolt to 3/8-16. Even the good US made CST ones cost less than $200. You see those big orange and yellow tripods in use along the highway all the time. They have to be sturdy.

 

[-persimmon-tree-]

But what will be the penalty to the resolution and hue quality of that 9-stop ND filter? The good ones don't come cheap, especially in 82mm diameter. With black and white, it's easier to use a slower film and a deep contrast filter. And one can never go wrong investing in a sturdier tripod. I use the same tripods for my 300 mm P67 lenses as I do for my 8x10 camera. Simply slowing the exposure way down makes the scene and the gear itself far more susceptible to wind gusts. Otherwise, yes, there is more than one way to skin a cat.

Short on money? Simply convert a wooden, fiberglass-clad survey tripod from its 5/8-11 turnbolt to 3/8-16. Even the good US made CST ones cost less than $200. You see those big orange and yellow tripods in use along the highway all the time. They have to be sturdy.

Can you recommend any specific tripods by name for me to start researching? I am using a pretty cheap tripod and I'm not going to be able to replace it any time super soon, but I'd like to start getting an idea of what to expect. Thanks!

 

[Sanug]

If you live in Europe, I can recommend the wooden tripods brand Berlebach. Sometimes second hand and very cheap at ebay, or available new from the factory in Germany as well.

I own an older model of the report series.

Berlebach Report

 

[-persimmon-tree-]

If you live in Europe, I can recommend the wooden tripods brand Berlebach. Sometimes second hand and very cheap at ebay, or available new from the factory in Germany as well.

I own an older model of the report series.

Berlebach Report

I live in the US on the west coast now, so no luck. Looks like prices are fairly high to buy new online. Still will keep an eye out, thank you!

 

[DREW WILEY]

When it comes to 300mm and longer P67 lenses, the problem with that Berblach is that it does not have a flat platform top, but a domed one; and as shown, any kind of ball head would be counterproductive. I use Ries wooden tripods. There is some controversy about their level of service at the moment; but it was excellent back when I bought mine. Ries are rather expensive, but they do turn up used sometimes.

My carbon fiber equivalent is a Feisol CT3472 with a self-customized top. It's much lighter than the bigger Ries, but solid. These have gone up quite a bit in price since I bought mine. The heads are adaptable.

If you want to go the survey tripod route, a new CST Berger US-made wood/fiberglass 60-WDF20 can be found several places online for under $150. Really solid, but 16 lbs, the kind of tripod you'd want to dedicate to a big tele or 8x10 camera, but not general usage. It will cost you about another $10 to convert the turnbolt to 3/8-16 or 1/4-20 thread using common hardware store parts. Try to find stainless steel. McMaster Carr is an excellent online source for such parts.

Incidentally, the Leica survey tripod selling for three times the price is the same thing, just private-labeled for them. I also had CST private label these for the company I was the purchasing agent for,
but certainly didn't mark them up that exorbitantly. About half of them actually sold to photographers, the rest for surveying lasers.

DO NOT buy aluminum survey tripods. Those are flimsy junk. In fact, don't buy look alike pseudo-CST wood/fiberglass tripods made in China; the locks fail quite prematurely. Real CST should be available in many countries, including the EU, since that manufacturer is now owned by Bosch, a very large German company.

 

[Lachlan Young]

the problem with that Berblach is that it does not have a flat platform top, but a domed one; and as shown, any kind of ball head would be counterproductive. I use Ries wooden tripods.

That Berlebach is pretty old - it looks more like some of the DDR era ones, or those that were sold under the 'Wolf' brand (from recall, when the relevant VEB was privatised, Berlebach and Wolf were the successor companies with different specialties). The current Report range has two different flat top variations, and the Uni range is much more like the A-100 Ries (which is the specific model I think you are referring to) type of design.

Either way, it's the shutter behaviour that's more of a potential issue than the need for MLU. And it's quite obvious that the Pentax was initially conceptualised as hand-held first, tripod second - and I think a lot of those who spend an awful lot of time worrying about tripods and any of the 6x7 SLRs would be better off just getting a classic aluminium Gitzo Series 4 or 5 (or equivalent) tripod and being done with it. And there are heads perfectly capable of handling the Pentax 6x7 (Linhof, Arca, Gitzo series 5 etc), it's just that they aren't common in the bargain basement.

 

[DREW WILEY]

Thanks for updating me on current Berlebach offerings.

I was painting the distinction between ordinary usage and their heavy longer teles. Heck, I've used both an old Gitzo "Reporter" series pan/tilt head all along, combined with,first, their Reporter set of aluminum legs, and then their first rendition of Reporter CF legs, for all of my backcountry P67 needs up to 200mm (for day hikes or road work, I prefer my lighter "J" wooden Ries) . But 300mm or longer presents a whole different kind of challenge. Even my ole heavy cast Bogen head atop a survey tripod didn't handle that ideally. I meant what I said, and do bolt the whole affair directly to a platform top of my bigger Ries, just like I do with an 8X10 camera. It does make a real difference, especially for windy outdoor use. That is my wheelhouse.

The thought that the Pentax 6X7 was "conceptualized" for "handheld usage first" doesn't make a lot of sense to me. It did address the ergonomic clumsiness shortfalls of more boxy MF SLR's, and certainly improved hand holding in that respect, and fashion pros often handheld it in relation to high-speed flash; but it's unthinkable that tripod dependence wasn't also in the picture from the get go, since they offered an especially serious selection of teles early on. Even their monster 800mm Takumar goes back to the days of their first 6X7 model (non-MLU). And for a cannon barrel like that, one needed more of an astronomical mount than a studio one.

And for us outdoorsmen, there are numerous reasons why aluminum tripods aren't ideal. Your skin can freeze to them in cold weather. Leg sections can freeze together when left wet. They are in effect a lightning rod - not kidding about that whatsoever! On inclement nights above timberline, I'd leave the old alum. Gitzo 50 yards from my tent. If I hadn't, I wouldn't still be around to write this. Not all of us were funded like Shirakawa, who had many porters and assistants to lug around expeditions supplies, including his big Series 5 Studex. But he did much of his best work from the air - and that's where the P67 system excels handheld, since everything is at infinity and relatively wide apertures can be routinely used.

The mirror kick is a far more significant issue than in smaller 6X6 or 645 MF SLR's. Shutter curtain vibrations only come into play with exceptionally long tele work. I learned of all that quite precisely from a person who was not only a specialty dealer for the Pentax 6X7 system and Celestron telescopes, etc, but also technically the best tele photographer I have even known. His very best personal setup consisted of a big Toyo M 8X10 view camera with a 360/9 Apo Nikkor process lens in front, and various SLR's at the film plane - often a Nikon 35mm, but sometimes a P67 body. He wasn't much of a hiker, so he'd use the heaviest tripod legs he could find.

Nowadays, the true astro types have largely converted to digital capture, including the Pentax 645 product, in relation to P67 EDIF teles, especially the 300's and 400's. But those guys might invest 40 thousand dollars or more in their notion of a "tripod". Add a big V8 truck or camper van, plus a custom trailer for hauling their portable observatories up to high altitude, and you're easily talking about hundreds of thousands of dollars overall. .. Nearly as much as what one pays for a 10-sheet box of 8X10 color film these days!

The highest auto road here in California is paved up to nearly 11,000 feet, before it goes dirt and bumpy. It leads to the Bristlecone pines in our White Mountains - a dry desert range with clear air, in the rain shadow of the even higher Sierra to the West. Sometimes you'll see several of those astro enthusiasts parked on the limited number of paved turnouts up there. I've seen em haul even 18 inch reflector telescopes up there, typically made with big concrete pouring Sonotubes to keep the weight down.

 

[Oren Grad]

So I wanted to ask, how big of an issue is the mirror slap?

Mirror slap isn't the whole story. The shutter mechanism itself is sufficiently massive for its pre-exposure action to cause trouble in some situations.

Here's what Ctein, who used the Pentax system for many years, wrote about it ~20 years ago:

The Pentax 6x7 is well-damped down to 1/30th of a second. The mirror slap is actually on the low side for a mirror that big. The vibration problem occurs when you go to 1/15th. At that speed, you practically have to bolt the camera to a concrete pillar to get it to hold still <g>. It gets *better* again below 1/15th.

When traveling with a relatively lightweight tripod (not my 20-lb Bogen monster), I'll stop down two more stops, if possible, and expose at 1/4 sec rather than 1/15th second, if possible. The results are notably sharper.

I don't know why 1/15th is such a big problem. Some of us have discussed whether there might be a mechanical resonance having to to with the timing of the release of the two shutter curtains. It seems unlikely it has anything to do with the mirror, since that wouldn't get better again at low speeds. Be that as it may, all explanations are hypothetical, to say the least! The observations, though, are reliable....

I know a lot of 6x7 users. None of them report that the camera exhibits an unusually high level of vibration for a medium format SLR. And most of us have used a lot of different medium format cameras. Whether it makes the camera suitable for your specific need is another matter entirely. If you need a really low level of vibration, none of the 6x6 or 6x7 SLR's are going to do the trick. You'd be better off with a medium-format rangefinder or the Pentax 645, which is extraordinarily well-damped.

His comment is way down toward the bottom of the discussion on this page:

https://groups.google.com/g/rec.photo.equipment.medium-format/c/Cwpq_aGDLnU