Sensor reflection/ghost images

Just to look at the other side of the coin here ;-0......but I remember when I used to add len flares in post, and all that time spent learning how to whack it while still keeping focus and buying that cinemorph filter to get oblong bokeh and horizontal streaks and......

ahhhhh, just don't kill the cameras personality.

Next thing you know, someone's gonna try tellin me 8mm don't look cool. just sayin....
 
Great thought, Frank. I use a hot mirror in conjunction with an ND usually and love it. Only issue I have is the edges of the frame tinting green with wide focal lengths (due to the angle of view toward the outside of the lenses' field of view).

I have not noticed a decrease in reflections with the hot mirror but I HAVE noticed a decrease in reflections when removing my ND filters (which goes along something you posted a while back). The type of ND doesn't seem to matter for me.

Something interesting: we received a sensor cover update kit for our Red a while back. It was a piece of tiny, thin coated glass that mounts in front of the sensor. I'm wondering if this is something the higher-end full sensor cameras have that the FS100 doesn't.
 
The far red extension 'feature' of the EX1 is well documented. The Tiffen T1 is a great solution to this.
I'll try to provoke lens flares on my FS100 and see if a T1 on top of my Heliopan Variable ND helps alleviate the issue.
 
I did exactly the test you're planning, Duncan, and - while the reflection disappeared - it's still inconclusive, as adding/removing any kind of glass to the stack can have a similar effect :)
 
For those who are interested, I've been talking to another filmmaker through Vimeo who was having similar complaints regarding sensor reflections and we recently heard back from Sony.

We were told that engineers were aware of the reflection issue and, though it's not considered a defect per se, this issue is being addressed in the FS700. Interestingly, when comparing notes, the other guy and I both noted how the rep kept speaking as if the FS700 was designed to replace the FS100--almost as if the FS100 was a Beta version of the FS700.

To be honest, you kind of get used to working around it. I equate it to an old VW I used to have... the door handles were broken so there was a trick to opening the doors - and after so long I got so used to it that I wouldn't even think about it. Only thing was only I could open the doors.
 
It does seem greatly improved in the FS700. In the side by side Abel Cine candle test, the sensor reflection of the candle was clear as day in the FS100. In the FS700, it was a lot less thankfully.
 
danstone said:
For those who are interested, I've been talking to another filmmaker through Vimeo who was having similar complaints regarding sensor reflections and we recently heard back from Sony.

We were told that engineers were aware of the reflection issue and, though it's not considered a defect per se, this issue is being addressed in the FS700. Interestingly, when comparing notes, the other guy and I both noted how the rep kept speaking as if the FS700 was designed to replace the FS100--almost as if the FS100 was a Beta version of the FS700.

To be honest, you kind of get used to working around it. I equate it to an old VW I used to have... the door handles were broken so there was a trick to opening the doors - and after so long I got so used to it that I wouldn't even think about it. Only thing was only I could open the doors.
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Brilliant! Now we're treated to the FS100 being a beta camera. Right!

Presumably the PD150 was a beta for the PD170 or the EX1 was really a beta for the EX3?

You keep trying to flog the sensor reflection dead horse, why not get in you old veedub and drive off to another forum and talk sensor reflections there?

With the shear number of combinations of lenses and adapters that can be put in front of the FS100 sensors how can Sony eliminate sensor reflections? The Canon C300 does a marvellous job of creating sensor reflections when using Canon's own glass, what the heck were they thinking?
 
Nirv said:
Brilliant! Now we're treated to the FS100 being a beta camera. Right!

Presumably the PD150 was a beta for the PD170 or the EX1 was really a beta for the EX3?

You keep trying to flog the sensor reflection dead horse, why not get in you old veedub and drive off to another forum and talk sensor reflections there?

With the shear number of combinations of lenses and adapters that can be put in front of the FS100 sensors how can Sony eliminate sensor reflections? The Canon C300 does a marvellous job of creating sensor reflections when using Canon's own glass, what the heck were they thinking?
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You seem to have missed the part where I wrote "for those who are interested," which would include the adults who are having a civilized conversation about something they consider an issue. You're obviously not interested, so how about you stop following me with your angry rants? You must have other things to do, no?
 
danstone said:
You seem to have missed the part where I wrote "for those who are interested," which would include the adults who are having a civilized conversation about something they consider an issue. You're obviously not interested, so how about you stop following me with your angry rants? You must have other things to do, no?
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Well Dan, if you were really interested in getting to the bottom of the "reflection issue" you would have already done so. The reflection has nothing to do with the camera and everything to do with the operator i.e the amount of light entering the lens, the lens and ND or ND Fader you have in front of the lens.

The FS700 is likely better due to built in ND filters although this won't stop all ghosts because some are lens related and there is no perfect anti-reflectant coating.

I don't believe you have been in discussion with Sony because they would've very quickly explained what causes the reflection and how to mitigate it, it takes 5 mins to recreate your "issue" and solve it.

Your style of shooting may be better off with a PMW-100.
 
Nirv said:
Well Dan, if you were really interested in getting to the bottom of the "reflection issue" you would have already done so. The reflection has nothing to do with the camera and everything to do with the operator i.e the amount of light entering the lens, the lens and ND or ND Fader you have in front of the lens.

The FS700 is likely better due to built in ND filters although this won't stop all ghosts because some are lens related and there is no perfect anti-reflectant coating.

I don't believe you have been in discussion with Sony because they would've very quickly explained what causes the reflection and how to mitigate it, it takes 5 mins to recreate your "issue" and solve it.

Your style of shooting may be better off with a PMW-100.
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Sorry Nirv, but you are wrong. The FS100 *is* worse than a lot of other cameras with it's reflection issues. Not that you can't work around it, but for whatever reason, the design of the sensor layers lends itself to reflecting much more easily AND with a heavy green tint than any other camera I've used.

When I first got the FS100, it popped up immediately and I thought maybe there was something wrong with the camera. It's not like my shooting style just changed immediately when I got the camera, because it didn't. Things I had shot with the AF100 now on the FS100 had worse reflections, so much so, they were too distracting. Things I had shot with the 7D now that I shot with the FS100 that didn't have the issue at all before had overwhelming green reflections.

For me, if the FS700 has less reflection, that's a good thing. People want to know that, me included. That's a HUGE selling point for me.

And to say the reflection issue has everything to do with the operator and not the camera? No, again, it's about both. It's just a limitation that gets added to your shooting with the FS100 and it's frustrating at times. (Like the limitation of slow rolling shutter on say older DSLR cameras).

If you can live with it, or accept it, that's fine, but others don't like it, and would rather NOT have to work around it.
 
Rick Burnett said:
Sorry Nirv, but you are wrong. The FS100 *is* worse than a lot of other cameras with it's reflection issues. Not that you can't work around it, but for whatever reason, the design of the sensor layers lends itself to reflecting much more easily AND with a heavy green tint than any other camera I've used.

When I first got the FS100, it popped up immediately and I thought maybe there was something wrong with the camera. It's not like my shooting style just changed immediately when I got the camera, because it didn't. Things I had shot with the AF100 now on the FS100 had worse reflections, so much so, they were too distracting. Things I had shot with the 7D now that I shot with the FS100 that didn't have the issue at all before had overwhelming green reflections.

For me, if the FS700 has less reflection, that's a good thing. People want to know that, me included. That's a HUGE selling point for me.

And to say the reflection issue has everything to do with the operator and not the camera? No, again, it's about both. It's just a limitation that gets added to your shooting with the FS100 and it's frustrating at times. (Like the limitation of slow rolling shutter on say older DSLR cameras).

If you can live with it, or accept it, that's fine, but others don't like it, and would rather NOT have to work around it.
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Beautifully said.
 
Rick,

Most of the issue is caused by lack of NDs behind the lens and the reflection is due to the filtration at the front of the lens. NDs work both ways and so does the aperture so any reflection is being stopped down on its way out. The length of the lens also appears to have an influence, physically longer lenses appear to be largely free of the problem as the reflection is no longer focussed on the back end of the ND fader. Lens choice helps here.

Shooting wide open at very intense objects i.e. windows is poor technique only possible with the better 1/3" cameras and their sensors were so small the reflections were often hidden in lens flares. Anyone my age 40+ has always avoided windows and backlighting like the plague because our cameras had about 2 stops of dynamic range. However, the reflections are very sensitive to direction and a few degrees change in angle can eliminate the problem completely. I have only ever encountered the issue when (on purpose) shooting into a blown out window with the aperture wide open and reducing the contrast will fill lights or reflectors would have been the fix. Stopping down to expose more toward the bright object and lifting up in post is also an option. Good light control with matte box, french flags and barn doors all help if you want to go that far.

I posted several examples of other large sensor camcorders exhibiting the same issue and they don't have the excuse for not having built-in ND filters. All large sensor camcorders reflect light as there's no perfect anti-reflective coating a sensor can be painted in. You may not have seen the issue on other cameras because your lens choices may have been different or at least better suited to those other cameras or in the case of the AF100 it has a smaller sensor and reflects less light.

There are many ways of mitigating sensor ghosting and all are down to the competence of the operator to know which is the best course of action to take for the situation. The Alexa has similar issues but nobody is claiming it has a problem are they?
 
Rick Burnett said:
If you can live with it, or accept it, that's fine, but others don't like it, and would rather NOT have to work around it.
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They have a choice to either quit moaning and learn to use the camera as intended and competently or sell it and use another camera better suited to their "style" of camera work. No?
 
 
Nirv said:
They have a choice to either quit moaning and learn to use the camera as intended and competently or sell it and use another camera better suited to their "style" of camera work. No?
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I disagree with your statements because you are making a lot of assumptions as to what people are doing and getting the reflections. This is without ANY ND filters at the front of the lenses. I am telling you that I spent a long time working with this issue studying why it was so much more worse with the FS100 than say the AF100 and the 7D. I owned ALL of these cameras at the same time, using the same lenses, shooting the same material.

In fact, I've studied the effect through examples of other cameras, and film itself. It's not to say the issue hasn't existed in other cameras, it DEFINITELY is an issue. But, on the FS100 it is worse. For instance, on the 7D I've VERY RARELY seen a sensor reflection. The only time I've dealt with reflections is when I put a filter on the front of the camera. This is not a sensor reflection, this is a filter reflection with the front glass of the lens and the back side of the filter. Different issue. In addition, the color of the reflections on say the 7D were not green, like the FS100 (and the AF100).

It's easy to make the reflections worse by using say a lens adapter that has a shiny interior (or leaks light). But, even Sony lenses without an adapter suffer from the problem. In my testing there are two things that result in affecting the flare in terms of the lens:

1) The curvature of the back of the last lens element.

2) The aperture size.

Depending on how the lens is curved, the reflection from it back to the sensor can either focus, or expand the light. This can HEAVILY influence how pronounced the reflection looks.

The aperture size affects how much light is coming in and bouncing off the side walls getting to the sensor face. This is why a longer lens has less of a problem, because the aperture size tends to be a lot smaller so the light is more collimated as it hits the sensor and not getting reflected by it.

What is CLEAR to me is the coating on the FS100 sensor isn't the best for what it is being used for. I can take the same lens, put it on my 7D and have NO sensor reflection in the same situation.

Why is it so hard to accept that Sony could have engineered a better coating? Obviously if reports of the FS700 having less reflection would indicate that in fact, they could have done better, and now they have. It's okay to be critical, it's how Sony would know people wanted something fixed/changed.

And when you tell people that they should use the camera as intended, you don't seem to get that people are and the issue comes up. The camera has an issue that behaves worse than other cameras above, below and in the same price range. Like I said, it's not like I got the FS100 and all of a sudden just changed my shooting style to make the reflections worse. They are worse, period. If YOU want to work around that and think it's fine, hey, that's your choice. But to me, it's a pain in the neck and it adds another thing I have to deal with in the camera that works in a way that I don't really like. It's just like dealing with rolling shutter. Sure, other cameras having rolling shutter, but say on the Nikon D90 it is absolutely horrible. Just because other cameras reflect doesn't mean one that does it worse isn't a valid criticism. And it also doesn't mean I don't love a lot of things about my FS100, which is why I use it in my productions.

People *get* that the FS100 can't be the best at everything, it has a price/performance target. But it also doesn't mean that people just have to ignore an issue. New people with FS100 who are seeing this will now have a thread to understand many things about the issue. What causes it, what makes it worse, what some solutions are to getting around it, and, that if it ends up being too much trouble for some people, maybe they might think about the FS700. And hey, I am happy that Sony has addressed it, just like they addressed other concerns of mine that I've brought directly to their attention. I fully plan to move to the FS700 eventually, but for now, I am continuing with my FS100 and I am working around the issue.
 
Nirv said:
Well Dan, if you were really interested in getting to the bottom of the "reflection issue" you would have already done so. The reflection has nothing to do with the camera and everything to do with the operator i.e the amount of light entering the lens, the lens and ND or ND Fader you have in front of the lens.

The FS700 is likely better due to built in ND filters although this won't stop all ghosts because some are lens related and there is no perfect anti-reflectant coating.

I don't believe you have been in discussion with Sony because they would've very quickly explained what causes the reflection and how to mitigate it, it takes 5 mins to recreate your "issue" and solve it.

Your style of shooting may be better off with a PMW-100.
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Not sure where the hatefulness is coming from in these messages but please leave them out. I've learned a lot from this thread as well as others that some people might find boring, yet others find informative. Remember, there's always someone who knows more than you and someone who knows less. Constructive comments are appreciated by people like me who want to learn. Thanks for your understanding.
 
Postmaster said:
It's not something Sony specific. Actually it's even well known on DSLRs

Also the Af100 is haunted: http://af100info.wordpress.com/2011/02/20/is-panasonic-af100-haunted/
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I for one am not arguing that other cameras don't deal with it, it's just worse on the FS100. I don't understand why people have to think in an all or nothing comparison with this issue. Like I said, most CMOS based cameras have rolling shutter, but I think everyone could agree the rolling shutter on the D90 is almost unusable in any kind of camera movements whereas with the FS100, I have RARELY had a problem with the rolling shutter. Sure, if I had my camera mounted on say a motor bike it would be a problem, but, if people thought the D90 was acceptable rolling shutter, Sony would have had no reason to make theirs faster. Or even say the AF100 rolling shutter versus the GH1.
 
There is really a simple solution here. Nirv, if you don't have an issue with reflections and/or are tired of hearing people comment on them, just unsubscribe from this thread. Other people here want to discuss the issue.
 
We have noticed it on the Canon DSLRs and the AF100 though not nearly as badly. I feel a sense of peace, though, to know that Sony is aware of the issue and that they're working on it. As bad as the reflections are on this camera, I'll take it over the 7D's compression blocking any day and the EX1's noisy picture.

I've learned that every camera has its own set of issues; you just have to pick your own deal breakers. The FS100 just happens to be a hot topic of mine right now because I bought it. I have twice as many gripes about the Scarlet and Alexa. The difference is I don't own them; I rent those and let a DIT deal with their issues.
 
I don't have any issues with reflections and I am willing to help anyone who is and who wants to learn. So if there is anyone who wants help do feel free to PM me.

On the other hand, if you feel pointing a fast lens at blown out windows is your thing and are unhappy with the FS100's inability to defy the laws of optical physics then can I suggest you continue posting to this thread where I'm sure you will receive all the necessary consolation.
 
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