Pulsating image degradation

[Nitsuj]

I have been working with the GH1 to try and find out what this is and I can't seem to find the answer yet. I am wondering if anybody else has seen this. At times, it seems to depend on certain low light situations, I notice what looks like pulsating mud. It will degrade maybe twice per second at a constant rate. I turned off the O.I.S. thinking it was something about the lens stabilizer. That didn't seem to change it. I have turned off auto focus and that isn't it either. I am at a loss at this point what it could be. I get it in 720 and 1080p. I thought maybe it was my system during the encoding process however I viewed the direct .mts file using VLC (I know that has a lot of artifacts when viewing) but now I am at a loss as to what this could be and how to avoid it.

Anybody have any ideas?

Video example of what I am talking about

http://exposureroom.com/60839febfaa540f8964174db9c269468/

[Cranky]

GOP size is 15 frames ==> 2 I-frames per second in 30p. One more evidence of how crappy the GH1's codec is. I usually see this when encoded with free/cheap DivX or Mpeg-2 codecs and low bitrate. In particular, I see the same pulsating with Mainconcept MPEG-2 encoder, what I do is I set it to insert I-frame every 3 frames, this helps. But you cannot tweak the built-in camera codec like this, so you are stuck. The only hope is for firmware upgrade.

[Nitsuj]

Thanks Cranky for your input. I will look into that I-frame set. I was beginning to suspect as such.

How about anybody else with the GH1. You guys found a work around for this yet? It almost seems to me at this point the lighting needs to be flat and camera should be moving at all times. I really notice it when the camera is locked down.

I'm right now running through every possible setting on the camera and it is looking like Cranky has hit the head. I guess now is trying to find a way to mask it.

[Mike@AF]

I haven't seen what you're referring to. Maybe I'm not understanding. Can you post a video or a short sequence of frames showing the anomaly?

[Nitsuj]

I'll see what I can do. Just finishing up my testing first.

[Nitsuj]

I just finished up running through different shutter speeds at different ISO and it looks like shutter has a lot to do with how well you can see this. Seems like the higher the shutter the more visible it is. Anything at 60 or higher looks worse. However at ISO 400 I can see it from 30 on up. ISO 100 with shutter between 30 - 60 isn't really visible. Same goes at the other end with ISO 1600 30 - 60 not really visible. Sucks that the ISO sweet spot seems to be 400 where the problem is more visible in those shutter ranges.

[Martti Ekstrand]

Are you perhaps seeing the interference effect with electric light frequency?

[Mike@AF]

Why would you shoot greater than 1/60 shutter? If you're shooting 1080 you should shoot with 1/50. If you're shooting 720p60 you should shoot 1/60. And if you're shooting 720p30 you should shoot 1/30 or 1/60, right? Do you still see the anomaly when you shoot at those shutter speeds?

[Cranky]

Are you perhaps seeing the interference effect with electric light frequency?
Ah, this might be it. But without seeing the actual video it is hard to diagnose the problem.

Nitsuj, can you shoot some tests outside, in daytime?

[Nitsuj]

Ah yes I am aware of the shutter speeds to use but it seems to really bring out the problem when raising the shutter speeds. It is still there at 1/50 @ 1080p. I first noticed it at 1/60 720p.
I recently discovered that certain film modes hide it better than others. For example Standard film mode seems to hide it better than Smooth however this is also depending on the lighting and gives me different results. Different results drives me crazy because it is hard for me to write down what not to do. I will figure this out if it kills me. ;)

I will put a vid together to show what I am talking about. It's pixels that are distorting 2 to 3 times a second and it is only at certain light levels. Seems to be at the edge of shadows. I did notice it outside as well on a previous test. It was what made me notice it. Since I have seen it outside I don't think it is the interference. I should get something together by tomorrow. I'm on Baby detail at the moment with my 3 week old and have to stop my testing. ;)

[nathankw]

I'm pretty sure I've seen exactly what you're talking about and (at least in my case) it was nothing to do with the camera, it was down to the playback. As has been said, the file you end up with has P frames every half second or so and I frames in between. If the playback method you're using doesn't interpret these properly the I frames will look different to the P frames giving that regular pulsing. I saw this with VLC and also with the free included playback software. However, when I played it direct from the camera or when I converted it properly there was no pulsing.

So assuming you're getting the same effect as me, its not a problem with the original footage or the camera so don't worry.

The best way to find out is playback using the camera.

[Nitsuj]

I'm pretty sure I've seen exactly what you're talking about and (at least in my case) it was nothing to do with the camera, it was down to the playback. As has been said, the file you end up with has P frames every half second or so and I frames in between. If the playback method you're using doesn't interpret these properly the I frames will look different to the P frames giving that regular pulsing. I saw this with VLC and also with the free included playback software. However, when I played it direct from the camera or when I converted it properly there was no pulsing.

So assuming you're getting the same effect as me, its not a problem with the original footage or the camera so don't worry.

The best way to find out is playback using the camera.

I'm putting together some test video together to check out this theory. I am viewing it first within FCP after a log and transfer. Then after removing pulldown I am viewing the QT file in quicktime. I am wondering if this is true because in VLC I get all kinds of artifacts and to me it is useless. I hope you are right because it may not be a problem for web viewing but I could only imagine what it would look like blown up on a silver screen or even an HD tv for that matter. (I don't watch TV so I don't have an HD set) I'll throw this up on exposureroom or something and see what it looks like there. If it isn't seen there then that is another clue that your theory is correct which I can only hope. ;) Thanks for the input.

[Nitsuj]

I have uploaded a video example of what I am talking about. Maybe somebody can shed some light on this. It doesn't happen all the time, just in certain situations.

http://exposureroom.com/60839febfaa540f8964174db9c269468/

I also found it on Philip Blooms beach video. It is in the clouds in certain shots. It is faint but I can see it. If I can figure out a good way to avoid it and not be a surprise to me then I will be golden. You really can't see it in the LCD on the GH1.

Could it be related to the stock lens? I don't recall seeing it before but then again I wasn't really looking for it until I found it.

[Mike@AF]

Wow, I've never seen anything near that in anything I've shot so far, even in my tests where I really pushed the camera. And I have no idea what could cause that.

[Nitsuj]

I hope somebody does. I would like to get to the bottom of it. It isn't in everything. I have gotten a lot of great stuff out of it. What bothers me is not knowing exactly what causes it and how to avoid it.

[nathankw]

Have you tried connecting your camera direct to a TV (via HDMI) and playing back that way?

[Barry_Green]

If it's every 12 or 30 frames, then it's probably the i-frame kicking in. Is it always the first frame and every multiple of 30 from then on?

If so, it's yet another long-GoP issue. You're dealing with scenes there with extreme amounts of detail, so the i-frame probably doesn't have enough of a bit budget to encode all that detail, so when the i-frame comes up it goes "muddy", then the delta frames fill in the gaps for the remaining 29 frames of the group.

How to avoid it? Lessen the amount of detail (shallower DOF, or less harsh lighting maybe)... or don't shoot strictly static scenes where it's possible to notice the pulse...

I hate long-GoP. Have I ever said that out loud before? :)

[Cranky]

Yep, this is suboptimal long-GOP encoding. I get similar results with MainConcept MPEG-2 encoder bundled with Vegas. On the other hand, you don't see this on big production DVDs, because they use much more sophisticated encoders, multiple passes, and they filter out hi-freq details.

The problem is not in long-GOP per se, the problem is in implementation.

> I hate long-GoP. Have I ever said that out loud before?

Some members of this board prefer the 150 to 170 for smoother and more natural looks, because DVCPRO HD on the 170 shows noticeable macroblocking at times (and they posted frame grabs, so I saw it myself). Long-GOP is not evil, one just have to cook it right. As a computer programmer, I like long-GOP because it is a smart way to squeeze as much quality as possible from limited bitrate.

[Barry_Green]

As a computer programmer myself, I can appreciate the genius behind the technology. But as a video user, long-GoP has yet to be implemented in any codec with substantial enough bandwidth in order to make it a viable and valid alternative to intraframe for reliable professional use. PH mode is the closest I've found yet, and given the price point of AVCCAM products I find it a reasonable choice for that, but I'm not giving up my 170 or AVC-Intra any time soon.

If they'd keep the same bandwidth, but add GoP encoding, they'd improve video quality. But they never do -- they always take advantage of the GoP efficiencies to enormously shrink the bandwidth, but leaving behind the long-GoP issues that always crop up.

[Stephen Mick]

Barry,

I'd be curious to get your take on the Long-GOP results from the Convergent Designs Nano Flash unit. It seems from footage I've both seen and shot, that their implementation of 100Mbps Long-GOP is as clean as the AVC-Intra footage I've seen (though I can't say I've shot any). According to CD, 100Mbps is the sweet spot for Long-GOP, with little benefit beyond that number, even though you can go to 160Mbps on the Nano.

Granted, this is using the XDCAM 422 codec, but we're still talking about Long-GOP.

So as to the OP's issue, perhaps a combination of bitrate and implementation is the issue. Or, as I've not seen any behavior like this in my GH1, could it be a faulty camera/sensor?

[Barry_Green]

Well, see, there they've actually given it enough bandwidth. That's the thing. Instead of trying to use the GoP technology to squeeze the footage down to a ridiculously tiny bandwidth, they kept the bandwidth the same and used the GoP to increase the quality of the footage.

I'm sure, compression-artifact-wise, the NanoFlash is going to be comparable to AVC-Intra. It's still only going to be 8-bit vs. Intra's 10-bit, but in terms of overall compression it should be as clean.

[Kerplunk]

I have just seen this on a clip I shot in the woods yesterday with varying light conditions and a very slight breeze. Maybe describing what happened in my case may further help in understanding what's going on and how to avoid it.

Shot 720p 60 at 1/60. Tough light conditions with late afternoon sun filtering thru the trees - lots of stark contrast areas. in Film Mode had everything set at 0 except sharpness at +1. Shot in CMM Standard.

When first looked at footage in Premiere didn't notice any pulsing at all. Footage looked fine other than it needed more color. It was only when I added a quick and dirty saturation boost with the HSL effect that pulsing became apparent. Anywhere where the leaves were turning and reflecting changing light - even very subtly - caused the pulsing in that area. Also true of areas with shadows from those trees on the ground -- where the moiion of the leaves caused varying light. Lowering the saturation level reduced the effect. Turning the HSL effect off eliminated it.

Had planned on using the 3 way color corrector anyway so used that instead and boosted the saturation of the mids and shadows. No pulsing. Even with the level boosted to max at 200. That wasn't quite enough saturation so I added the HSL again, this time at a nominal level and am now a happy camper with no pulsing and a pleasing image.

Am wondering if I would have seen this pulsing right of the bat if I'd had more color in the shot to begin with -- say with saturation set at +1 or +2. Then again, had the pulsing shown up with those settings I'd have no way to correct it. Am really curious whether reducing saturation in those test clips would help reduce the pulsing.

Anyway, seems to me that it's lots of detail (as has been pointed out) and also varying light levels, however subtle, within those detailed areas that are the kiss of death. And it has something to do with saturation.

[Cranky]

Heh: http://www.dvxuser.com/V6/showthread.php?t=181978 Funny how similar threads appear in the same time. Not the first time I see it happening on this forum.

[Nitsuj]

This makes sense because I notice it more when it is static on trees. I too have noticed it is more subtle depending on the color mode in camera.

If only we could get a live HDMI out into one of those flash units. Of course that would mean a big chunk of change for me ATM.

I will probably put it through some more testing in the next couple of days to see if there is anything I can do in camera and in post to tone that down a bit.

I was starting to wonder if it was during the Log and Transfer that it was happening. When I view the .mts files in FCP before Log and Transfer I don't seem to notice it. However the screen is smaller and I haven't found a way to increase the size of the preview pane during log and transfer yet. You guys rock by the way, thanks for the input on it.

[Barry_Green]

Try playing back directly from the camera to an HDTV. My bet is that you will notice it there, and that it's not something L&T is adding.

[Nitsuj]

I'll have to get to an HDTV as I do not have one but I am guessing you are right.

[Cranky]

http://vimeo.com/6344564 For example, at 2:04-2:13 watch the grass. Some other places too.

[Nitsuj]

http://vimeo.com/6344564 For example, at 2:04-2:13 watch the grass. Some other places too.

Yeah it does seem to be extreme in grass and trees.
That video is cool. Funny, I am actually working on something just like that in Knoxville, TN.

[mtan]

so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger

[Ben_B]

"Anyway, seems to me that it's lots of detail (as has been pointed out) and also varying light levels, however subtle, within those detailed areas that are the kiss of death. And it has something to do with saturation."

Try turning sharpness up 1, contrast down 2, and saturation down 1?

[BradM]

I have a GH1 and 5D and I can say I have seen this on both cameras so don't feel alone :(

one of the new 7D clips http://www.robgalbraith.com/bins/multi_page.asp?cid=7-10042-10239-10240 has it clearly visible in the Thunder 1080 clip in the rocks below the walkway . As mentioned by Barry, the real only solution is slightly out of focus or slight movement. Wide nature shots of trees, hills and other full focus areas seem always the worse offenders.

[Barry_Green]

so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger
Okay, first of all, items 1/3/4/5 are all the same. And item 2 happens on pretty much all the CMOS camcorders, someone earlier went through and pointed out threads on Nikon forums complaining about banding on theirs, and on Canon forums complaining about banding on theirs.

Here's the bottom line: the GH1 can make exquisitely awesome imagery that people could easily believe could have come from a $40,000 Red One.

Or it can screw up the footage.

Only way you'll know is to play it back and see.

But it costs $1500, including lens, and right now there's nothing on the market that can touch it, anywhere near its price.

The 7D, maybe, but (body to body) it's over twice as expensive.

[mtan]

I know it is torture Barry, I want to buy the 7d with a great lens, I can afford it but my wife would decapitate me! The GH1 she already knows the price range, although I first told her 1200 so I will still get it.

[mtan]

I think will just repair my hv30 and pass on the gh1, I will wait for something better or for the price to drop on the 7d. I just can't do it, too many problems for so much money.

[Ben_B]

Go out and watch a lot of footage and see if you want get one, don't decide arbitrarily.

http://vimeo.com/groups/gh1

[mtan]

I really want something that will last a while and which I feel solid about, I want to grade my footage with confidence, I want the higest quality possible for such an expensive purchase. Good things come to those who wait. I just don't have enough confidence in this purchase. Maybe the gh2, I will wait.

[Cranky]

so we now have

1) Pulsating image degradation
2) Low light streaking/banding
3) Weak 24p Codec
4) Mud/poor compression
5) Low bit rate

Man this is killing me, I want to get this camera but can seem to pull the trigger
Nope. We observe 1, 2 and 4. The cause for these artifacts is likely 3 and 5.

[Ben_B]

1) Not a problem on mine.
2) Don't experience this with properly exposed footage
3) I shoot 720p/60 and convert to 24p in post
4) Not a problem on mine, especially not with 720p
5) So? Symptoms are same as 4. See 4.

[mtan]

I want 1080p, not to convert 720 60p to 1080 24p. The gh1 is already outdated in my view. In a year or even 6 months nobody will be even be discussing this camera, while the 5d and especially the 7d will have much more staying power since they can shoot quality 1080p as well as much better photographs on top of that. Gh1 now seems like a gimmick to me. I am so glad there was a delay so that I did not purchase it.

I can get 1080p 24p right now on my $500 HV30. Why pay $1500 for 720p, dof is nice but not that necessary to me.

[Ben_B]

It is possible to shoot a great image with 1080p/24 on the GH1, there is another thread about this, but I simply prefer 720p, I shoot 720p when I shoot on the HVX (usually) as well. I find that it gives me increased flexibility as I can use a 1080p shot to do a composite where I need to downscale, etc, and if I'm going to be editing in 720p I might as well shoot it. Plus with the GH1 (and with the HVX if not shooting 720/24pn) I can get instant slow-mo wherever I want.

There really isn't that substantial a difference between 720p and 1080p, especially once they hit the web, once you consider that most projectors (not like theatre digital projectors which are 2k or higher usually but like normal multimedia projectors, like those in large lecture halls, etc, where it's always good to have screenings) are usually not 1080p, and that broadcast is typically either 720p or 1080i, and that DVD is SD.

[Cranky]

broadcast is typically either 720p or 1080i, and that DVD is SD.
Don't fool yourself and others: 24p content is broadcast over 1080i with 2-3 pulldown, and any half-decent television set is capable of restoring full 1080p24 from such a stream. So in a way, 1080p24 is already being broadcast. Same goes to 1080p30, though 2-2 pulldown support is still not stellar on this side of the pond, I've heard it is much better in Europe, where they package 1080p25 into 1080i50.

[Ben_B]

Everyone sits far enough back from their 1080p TV's that there's no difference between 1080p and 720p anyway :)

[Cranky]

Everyone sits far enough back from their 1080p TV's that there's no difference between 1080p and 720p anyway :)
You know about everyone?

[Ben_B]

Ok unscientific but still interesting:
http://gizmodo.com/5280355/guess-what-many-of-you-wasted-money-on-your-1080p-tv-but-theres-hope

:D

[mtan]

I respect your opinion Ben and I am sure you could shoot something in 720p or SD for that matter that would look better than anything I did in 1080p. But for me who is an unskilled shooter I need all I can get out of resolution, bitrate, etc. I also want something that will last longer, 720p will eventually be completely replaced by 1080p. I want to hold on to what I buy for many years, people like you who are in the film profession probably have cameras all over the place and replace them all the time so having a gh1 is a cool thing to have because you have other options.

I would love to have a Gh1 for a very compact stealthy solution in addition to a heftier machine like the 7d, but I can only get one. The GH1 is pretty cool, I have a strong attachment to it otherwise I would not be posting here. I wish i could get several different cameras.

[Nitsuj]

I want 1080p, not to convert 720 60p to 1080 24p. The gh1 is already outdated in my view.


FHD on this camera is beautiful. The shots I posted were extreme examples. I literally had to search high and low to get those examples. And it came down to static shots of a lot of detail. This sort of things happens on a lot of cameras. This wasn't a post to show a flaw in the GH1, it was to find out what was causing it and how to work around it.

Nobody even has the 7D. Why does this keep getting brought up? It is silly throwing the 7D in every forum post.


In a year or even 6 months nobody will be even be discussing this camera, while the 5d and especially the 7d will have much more staying power since they can shoot quality 1080p as well as much better photographs on top of that. Gh1 now seems like a gimmick to me. I am so glad there was a delay so that I did not purchase it.


And this is based on what grounds? Sorry but I disagree completely.


I can get 1080p 24p right now on my $500 HV30. Why pay $1500 for 720p, dof is nice but not that necessary to me.

Then this isn't the camera for you. It has been said many times already, this isn't the camera for everybody. I suggest waiting for the HV50 or something.

[Cranky]

720p will eventually be completely replaced by 1080p
When this happens, the 7D will be exhibited in museums of old tech.

[Nitsuj]

Is it always the first frame and every multiple of 30 from then on? If so, it's yet another long-GoP issue.

Yes this is what is happening so I believe you are completely correct on what is happening. Thanks for your advice. I will keep all of it in mind when doing static shots.

[Ben_B]

Clearly you guys aren't familiar with resolvable resolution. It's the reason why say, 12k, will never replace 1080p. Even if you can pack that many pixels into asmall, say 60" display, at some point (not much further than 1080p as evidenced by data regarding the way in which 1080p on a normal sized TV already looks no better than 720p the further back you go) the human eye cannot tell the difference unless you're using a massive, say, IMAX sized screen, which we won't have in our houses.

I plan to hold onto my GH1 for many years. I may have shot on the HVX, EX-1, JVC-100 (which aren't even really pro cameras) but I've never owned one. The GH1 is the first thing better than a MiniDV Handycam I've owned...and I bought it because I wanted shallower DOF in my films for school, to get a better understanding and appreciation for cinematography, to document things I do and places I go, and because I didn't want to have to deal with the normal shennanigans of not being able to get the right piece of equipment at the right time for a shoot...my schedule is jam-packed enough without having to worry about whether or not I can get one of the five HMC-150s assigned for my class of 20.

But what you need to understand is that no technology is future-proof. If you keep worrying about what will get you the best possible image 10 years from now you'll never be able to buy a camera. What you need to figure out is what is best for you now and in the immediate future, get it, and make some amazing stuff on it. 10 years from now if your film is still good, and if you put a lot of love and work into it I am sure it will be, nobody is going to care what you shot on.

[Nitsuj]

I would have loved to use the GH1 when I was in film school. I used the Sony VX2000 and the XL1 for all my projects and this GH1 is miles ahead in my eyes. I was doing all kinds of SFX with those cameras (chroma keying) and there is no reason the GH1 can't even do better. Damn, I miss film school now. Anyway the GH1 is perfect for film school. I bet it will be better than the school's equipment.

[Ben_B]

Well the school equipment is pretty good. Classes use, in this order (least advanced to more advanced), HMC-150, HVX-200, EX-1. The HMC class was originally on GL2's until this year, so that explains why they're using what is arguably a better camera (in terms of optics, low light performance, etc) than the next class up using HVX-200s (not A.)

The TV station has two JVC-100u and two EX-1s that you can use if you put your film on the TV station in the end.

All in all decent set of equipment but none of it can really get to the DOF of a GH1 with fast primes.

Not that any of this equipment is particularly old but old equipment still does a pretty good job. I've got a friend that cuts VX-1000 footage next to his HVX in skate videos and it holds up decently (given that that is sort of the style for a lot of these videos---switching kinds of cameras, etc.) In fact he actually traded his DVX for the VX and some money when he got the HVX because it gave him enough left over to get an awesome, very expensive, fish-eye for the VX (which is mainly what he uses it for, and was using the DVX for.) We still miss the DVX though. That has to be one of my favorite cameras of all time.

But yes I think the GH1 is perfect for a film student, especially when it can be used to supplement the traditional video cameras the school has. I think learning to shoot with the features and limitations of a vDSLR is very similar to learning to shoot with the features and limitations of a motion picture film camera, which is something that we don't do at our school anymore.

[BhambuNath]

1) Not a problem on mine.
2) Don't experience this with properly exposed footage
3) I shoot 720p/60 and convert to 24p in post
4) Not a problem on mine, especially not with 720p
5) So? Symptoms are same as 4. See 4.

I've seen the #1 with green color.

[Nitsuj]

Ah... I did use a GL1 back in the day too. GL2's until this year eh? Well that is good they got good equipment.

When I went to film school back in 2001 - 2003 I chose the video route because I said then that Video was where it was going. While the other students were spending thousands on one or two films I was knocking out 20 with very little money. I did make a couple of 8mm shorts though and those were fun. We didn't edit them with NLE's so it was a good experience to actually cut film.

Oh btw I have been using an ND and PL filter which seems to be toning down the original problem in this thread. I'm gonna run it through another test tomorrow at the same location to compare. Not sure if it is going to help but after getting an ND filter on top of my PL filter the image looks even better. I highly recommend using the stock lens with an ND and PL filter whenever possible.

[Ben_B]

Yeah GL2's until they were replaced by HMC-150 but they've had the HVX and EX-1 for a few years now. EX-1 when they came out actually.

[PDR]

Not all AVCHD implementations are the same.

Part of the reason for the "muddy" look and I frame pusling is the GH1 uses a different AVCHD implementation than other cameras: 1) It doesn't use CABAC, and that alone represents a 20-30% compression loss. 2) There are no b-frames , so it's compression efficiency is lower than say, HMC150 or even consumer AVCHD cameras (such as HDC-HS300) at the same bitrate.

Shooting relatively still sequences might turn out ok, but as soon as there is motion, detail or any complexity, this camera will be less forgiving because of the lower encoding efficiency

[tkarlmann]

Please note: I am not a video expert, however I am interested in the GH1, and am a professional photographer.

With regards to your problem: I think it is the too-high shutter speeds you are using perhaps combined with AVCHD. In your video I noticed that the leaves were moving somewhat rapidly in the areas you outlined. This, combined with too-high shutter speeds, could cause the problem. Luminous-landscape recommends no higher than 1/50 sec shutter speed for video for the GH1, or 1/125 if you PP for slow motion.

As far as the Codec goes, the only thing I know about that is that the GH1's codec does not use "B" frames.

Please read this link: http://www.luminous-landscape.com/reviews/cameras/gh1.shtml
There is a lot detail here on the GH1's video.

Let me know if this helps you. Good shooting!

[Revsta]

That does suck, but try the same shot on a slightly longer lens. These issues always seem to crop up when people are so so wide and everything is in focus--which funny enough is the main thing type of shots people were trying to avoid with 35mm adapters and the DOF on this camera...